one thing that absolutely shocks and impresses me about this channel is the pace at which videos are coming out, the last 6 months seems like years worth of work
Yeah this guy is going into like Applied Science level depth on this project and just absolutely cranking out the videos. It's nuts. Between the work and video editing, he's gotta be spending like 20 hrs a week minimum to get these out this fast. Insane.
Absolutely love this video. As someone who got a degree in chemical engineering and therefore spent many, many, MANY hours learning every minute detail of designing and building plug flow reactors, understanding their governing thermodynamic equations, solving differential equations to characterise the fluid dynamics of the packed catalyst beds, understanding the materials science of the various alloys used to build them and the physical chemistry involved with zeolite-catalysed reactions, drilling down into details of details of details I never could have imagined existing before... It absolutely blew my mind to see someone casually building a packed-bed plug-flow reactor from plumbing parts and unspecified alumina beads in his garage, and the damn thing actually working! Seriously, well done! (Deep down I'm almost insulted by the fact you managed to get a decent yield without doing any equations to work out the reaction rate, and therefore flow rate and reactor length required 😂) I think your "missing mass" is probably unreacted ethanol and possibly some diethyl ether that makes it past the collector bottle (I'd call that a blowdown drum 😂) and dissolves into the bubbler water and or adsorbs onto your silica gel dessicant. The bubbler will probably catch nearly all the ethanol, and a bit of the ether (particularly as it picks up more ethanol) The burning of your collected liquid looks to me like it's due mainly to ethanol burning, nice and calm and blue. I'd expect ether to burn off much more excitingly if it were the major component. I suspect a good fraction (half?) of the diethyl ether your reactor produces is ending up in your final product and I would suggest trying to do a thorough job of removing it because it's just such an horrific fire hazard. Although its boiling point is like 35*C, it has an insanely high vapor pressure so most of it will stay as vapor at atmospheric pressure even when cooled below this. Even at 0 degrees its vapor pressure is something like 1/3 of an atmosphere so that's why I suspect you have a lot in your collected product.
Oh one more thing (sorry!) - I think your burner design probably needs more outlet holes or a more restrictive venturi inlet to work as intended. Looks like the flow in the pipe is stagnating because the outlet resistance is too much, so the pressure in the pipe matches the atmospheric pressure and the venturi can't draw in air. That said it might be for the best because it seems to do the job well enough, and unless you're quite careful with the nozzle design, there's nothing to stop the flame front moving inside the pipe if the mixture inside it is flammable. You can pack the pipe with some sort of metal mesh to mitigate this but obviously that creates a lot more resistance to the flow.
Any idea how I could calculate the change in temperature in a PFR? Not something complicated, just a simple 1D-model (so everything symmetrical essentially) with a fluid flowing through a packed bed, resulting in a reaction given pressure and temperature. But this releases reaction heat, which is then not just spread within the bed (lets call it conduction) but is also transported along the PFR with the fluid. So the next section of the PFR sees a hotter fluid, which means faster reaction, so more heat, so section 3 gets even hotter etc. I have a python model with the reaction and everything, but how to calculate dT/dz (z = lenght)? Sorry for this random question, but I dont exactly often run into other chemical engineers that do things like that. I deal with rotary kilns normally, hence most of the things are known. But in a rotary kiln the fluid does not pass through the solid, so this side of things is, sadly, unknown to me. But I want to get a simulation running to prove (or disprove) something I once told a client... just a gut feeling, but it seems to make sense (that the heat can accumulate and cause issues). And yes, I know that this can happen in PFR with calatysts (have seen ex-molten catalyst in a ammonia reactor), but in this case it is a ad/desorption (for regeneration) or a Cu-Zeolith, so things are somewhat different.
Great info! A curiosity: does this reaction equilibriate much? -- would excess H2O shift the balance in favor of ethanol or diethyl ether? (Also for reference, what's the equilibrium constant at ~1atm?) Is diethyl ether dissociated to ethylene on further heating? Seems possible the flow rate is too high, causing uneven temperatures (lower at the inlet, and in the center of the catalyst fill) as well as not having enough dwell time for reaction. Hmm, excess diethyl ether vapor should condense at the bottom of the pressure vessel, for the same reason water does (when compressing atmosphere). Not as much, relatively speaking, of course, but it should be at least diagnostic.
@@T3sl4 The reverse reaction, ethanol via hydration of ethene, is how a lot of industrial ethanol is produced. So that equilibrium will absolutely be shifted to ethanol with more water. The direction you take is endothermic, so heating helps both with reaction rate and conversion. The endothermic nature of the reaction actively helps reducing the temperature gradient in your reactor. However, getting a really isothermic reactor is essentially impossible. Even without any reactions happening, just moving a fluid through the reactor and ignoring radial gradients, you would have to adjust the heating along the length very carefully to get somewhat close. The equilibrium is highly temperature dependant, so I am not sure if one value would help you much. There are lots of papers on this... if you really want to dive into this and make some simulations. In any way, given your success, you dont need to waste any time on any of this. It works super good already. It is not like ethanol is expensive or you need scale production up 100x. You are not going to condense ether like that. It is mixed with ethylene, lowering the partial pressure. You would need very low temperatures to get most of it out of the stream. However, that would be a good idea as a step between the bubbler and the desiccant: Cooling it to... say -20 °C. And yes, for the same reason water condenses the ether will too once the pressure is high enough, since the partial pressure goes up too.
And it’s actually a good food source - algae grows rapidly on the plastic particles which is not toxic to sea turtles… Large sheets or ropes of plastic (like fishing nets and six packs rings) do block their digestion however…
For your calculations, the mass you distilled from the flask of everclear wouldn't be 100% ethanol because ethanol and water form an azeotrope. A mixture of 8% water and 92% ethanol has the lowest boiling point, so that was probably what you distilled over. Making your own ethene is astounding. Impressive yield.
@@wazaagbreak-head6039 How do you mess that up. Like seriously, how? There's so many places where you could type that comment and be funny, yet you picked the one place where it makes *YOU* become the joke. That's honestly impressive, but not in a good way.
As an (Bio-) Petrochemical AND Open Source Hardware nerd who wants to be able to make like *all the things* at a community/makerspace scale, this is AMAZING! Granted may need to be modified etc, and some things require larger scale (i wrote some wiki page on this), but having this chemical at this scale is an amazing addition to the toolkit! Really neat video, keep up the great work!
Wow, this is awesome! One thing that might improve your yield is actually pre-heating the ethanol vapor. It's hitting the catalyst at ~100C, so it takes the first few inches in the catalyst bed to actually get it up to 450C, so you're running with low selectivity on the first bit of the reactor. You could accomplish this by filling the first several inches with an inert material with a high thermal capacity to get the ethanol up to temperature so when it hits the catalyst it's at your target temp. Broken/ground glass should do the trick if you don't want anything fancy!
Sir, I admire your pirate attitude. Can't be any freeer as a person than when you take simple chemistry and apply it carefully to obtain difficult to get components. Your thoroughness in calculating yields and identifying by products are a testament to your interest in handling this stuff safely. I want to be like you when I grow up.
@@Preinstallable I agree but also disagree, since something being marked up to prohibitive levels is the definition of difficult to get. For the average person, when they see their options of "shell out for "store-bought" ethylene" or "build your own packed-bed plug-flow reactor", they're probably going to mentally file that under "difficult to get".
As a refrigeration mechanic I love the content and interesting take on all this. I’m currently sourcing all the parts I need for a cascade system.. Keep up the great content 👍
I worked for a rural HVAC company for 23yrs, and my boss passed away, so I took over. I'd been putting off my EPA test for 18yrs. I studied for two weekends, paid the $50 and passed it. It's an easy test, and the license is forever.
As a researcher working in steam reformation you absolutely nailed it. Gas heated reactors can be very hard to tune and can give all sorts of weird results due to the larger temperature gradients. The second batch also looks like you may have started reforming. The water gets used in the water gas shift reaction to make H2 and CO2.
Very cool video! I suspect that the liquid you collected after passing the ethanol over the catalyst is mostly a mixture of water and unreacted ethanol. Diethyl ether is immiscible with water, and only slightly soluble, so you would expect to see a separate layer if an appreciable quantity of ether was produced. Ethanol is also less dense than water, but fully miscible with water, so this may explain the lower density of the mixture. A lower concentration ethanol/water mixture isn't super flammable though, so you may be right that there is a little bit of diethyl ether dissolved in the water which caused the mixture to ignite. If you distilled the mixture to determine the composition, I suspect you'd find that it is mostly unreacted ethanol and water. I'm excited to see you use the ethylene as a refrigerant and look forward to that video! Great job.
in my experience it smells more than diethyl ether and something else, and not like ethanol at all. also it can be oily and stick to the bubbler - so I hope you got your dog a new bowl.
@@garbleduser ooh, very possible. Ethanol and ether are miscible. I agree that fractional distillation would be nice just to see what the composition is.
My IQ is for sure too low to speculate but maybe because of the way he heated the catalyst he had a range of temperatures at different places. Maybe a more consistent way to control temperature throughout the catalyst might help. Again I may not even be making sense I definitely am not even a novice.
I’ve been following this closely. I do HVAC Service for work, and have played with my own R290/Propane system before that had great results. I built my own tiny little system from scrap Dehumidifier parts, and I’ve also used it in a Window AC for shiggles. Both worked great! I’ve got so many random parts, this project seems like something I should try myself!
I also have a small collection of old refrigerators. I have a GE DR1 Monitor Top which is the “first” electric home fridge. It uses SO2 as refrigerant and that stuff is nasty. I do not want another whiff of that. I had to dispose of that with a bit of simple chemistry, and the perfect replacement refrigerant for the thing is R152A aka Air Duster cans! I ended up having to fix a leak in the bottom of the compressor, and I’ve had it sitting with 150psi of nitrogen in it for probably 6 months now. Can’t wait to fill it up again and get it cooling
Been watching this channel for a while but this project has made this my all time favorite channel. I've wanted to make a cryocooler for a while now and the amount of information with detailed explanation of the build and data analysis is GOLD. Can't wait till you get your first drop of cryogenic liquid!
@@captainotto I dunno about “nothing more” but yes it gets pretty depraved lmao. Feeling like a solvent plant definitely doesn’t help Edit: err, reeking. Not feeling. Well, that too I guess!
@@mduckernz Hunter S. Thompson - Fear and Loathing in Las Vegas But even if you read the book or saw the movie, you can't be blamed for missing it because I butchered the hell out of the quote and failed to attribute it.
Cool, thanks for video. There are also "autocascade" phase-change systems, using mix of different refrigerants while using the same compressor in system. Polycold is (was?) one of the famous manufacturers of such systems for industrial use. You still need oil separator, compatible refrigerants and some heat exchangers for system to work, but at least don't need additional compressor. Oil separator is needed for reaching low temperatures, otherwise it will freeze up and clog the capillary tube restriction.
It is a lot of cold storage brands out there, mainly running at -152C. Using auto cascade as you mention, but very few use a single stage system. The first stage pre-cool the auto cascade second stage system. Horrible pressure even with two stage due to the high pressure gases time to reach a condensation temperature. Often two oil separator in series and capillary tube heaters kicking in on cycle off periods by a timer to clean oil off the tubes. Very expensive gas mixtures on them with critically share of the gas un the mixed blend and the total amount.
You know its good when it takes an hour to watch 18minutes. So much invention , so much Science, its inspiring. The problem solving with modern day off the shelf parts is as impressive as the calculations. The numbers dont need to be exact, its the method which is demonstrated that hopefully leads to understanding in such a way that it is raw , Kg,m,s . Impressed by the whole project at every stage.
smell-test is not a great thing for cancerogenic anesthetic, but it works. I've made ethylene with the same method in lab, with just a butane torch heating it. FTIR showed almost complete conversion and MS showed lots of ethanol with the gas. your cleaning steps are very nice. i did run my catalyst in quartz tube, so i could eyeball the yellowing of the catalyst, and ethanol I evaporated in the same quartz tube from mineral wool. but I did not need 60 liters. Good Luck!
There is no evidence for carcinogenicity of diethyl ether, and no reproductive effects have been reported. Chronic exposure to diethyl ether vapor may lead to loss of appetite, exhaustion, drowsiness, dizziness, and other cns effects.
I am so envious of your motivation to start and then work on and then complete such a long involved experiment and film it at the same time. Once again I can only say thank you.
This is really interesting since a way of creating ethylene that I'm familiar with (and you kinda hinted at it in the beginning) is using sulfuric acid, the entire reaction uses sulfuric acid heated to 180°C: Ethanol ---(H2SO4 @ 180°C)---> ethylene + water you can see the benefits of that since it requires a much lower temperature that the method you used. Interestingly enough you could also use the same setup but at 140°C to make ethers as well and I think Neilred used it to make diethyl ether from ethanol quite a while back.
I'd be really wary of using the sulfuric acid method because it's also very likely to generate some amount of diethyl sulfate, which is a strong alkylating agent. Very toxic, very carcinogenic, very very nasty.
@@jhonbus Good call. Apparently diethyl sulfate can be made by bubbling ethylene gas into hot, concentrated sulfuric acid so this really is a valid concern.
I was going to mention this. I've used this plenty of times with various alcohols (think I managed acetylene from 1,2-propadiol with a peroxide kick once) and it's got so many advantages on laboratory scale. You just need a flask, a heat source, and sulfuric acid; they only need be good enough quality to get the job done; and you can use all of the components for whatever else you want if you're satisfied with your alkyne gas situation because there's no special apparatus. PS: yes the sulfate ester byproducts are carcinogenic as hell they're alkylating agents, if you're collecting the alkene gas you're making for non immediate use or making enough that alcohol addition dropwise is too slow, you need to run the output through alkali before getting your mortal, cancer vulnerable fingies near it.
As a refrigeration mechanic by trade i love this stuff. As a professional pyrotechnition i love it ecen more. As an apprentice i worked on a ultracold bone cabinet it ran a R502 cascade system to a R503. We added ethelene to prevent waxing and capillary freeze up blockages. Our target temp was around -82deg c. The power bill was bad for just 2 weeks run time. All the same great content
Just a couple of thoughts from a chemist... Crush the catalyst beads for more surface area, better conversion. Ether is soluble in water to around 6% w/w so you should see a phase separation at any higher than that if theres no ethanol in the mix. You can break the water-ethanol azeotrope by adding a ternary solvent but whats the point, your byproduct is water. The major difference between what you did and the sulfuric acid dehydration route, from an engineering perspective, is continuous vs batch process. Play with the residence time of your ethanol vapor on the catalyst bed to increase yields even more and run it vertically for better mixing. Anyways, good job, enjoyed watching this!
So happy I found this channel! Very cool project, narrated at a pace that keeps you 100% focused with no fluff. Wish I could give more than one thumbs up!
First of all: You make absolute premium content for fellow educated nerds! ;) A hint on the yield: try to use pure 100% ethanol, dried with molecular sieves. It will increase the yield as you don't add water in what also is a waste product. All the reactions are equilibrium reactions. That tend towards a certain composition. Less water in will mean more water (and thus ethene) produced as the output gas stream will try to converge on the same composition, given the same conditions.
Love this. I was building a cascade system just like this about 15 years ago. I wasn't able to find a source of ethylene. Before I got that far, I got a severe frost bite on both hands from a propane leak in the first stage. I wasn't able to use my hands for 2 weeks. Be careful!
That shot of your 2 stage system, caught my eye. Early last summer, our AC started leaking R 22 out of it. Compressor was leaking. So, I started running R 290 in it. (Well, not refrigerant grade, but BBQ grade.) One bottle lasted all summer, and the landlord was able to find a replacement unit MUCH cheaper, out of our "warm" season Phoenix Az. Bought a weedburner from Horror Fright, cut the line, cut a line on my cheap set of AC gauges, and shot some R 290 in. Left the tank and gauges under the AC, so I wouldn't be carrying them up and down. At least once a week, or more often. steve
As an HVAC EPA Certified tech for diesel truck refrigerator trailers, i thoroughly enjoy this! I can probably get a high output 1994 unit for 1200.00 USD at LKQ... that's actually not a bad idea come to think of it... Some of those units use the R508, so if you had the opportunity, one could theoretically find a place that is decommissioning the retired units and offer a free service to recycle/dispose of the refrigerant for the yard, and then collect enough of what you need as well. Granted not everyone has a recovery system that can store used Freon, i get that.... Just a thought.
Cool video, fyi in your last video you had a heat exchanger, if you reverse the flow on one side you'll increase your effciency using contraflow cooling which uses "warm" coolant to pre-cool the "hot" coolant and cold coolant to chill the "warm(previously hot coolant)" down could gain you a few % in effciency for a change of plumbing
I think you are a genius. Just one an advice. To identify a gas is very easy. Just measure density with the help of the proper syringe, divide this by the density of hydrogen gas at the same pressure and temperature, multiplied by two; that is the molecular weight of the title gas.
Neat stuff. I’m a commercial refrigeration tech myself. When I first got into the trade we did some work for a lab experimenting space tiles. Similar setup to what you are making in terms of one refrigeration system cooling the condensor of another
Granted *Money* but having a good hit of basic Glassware, and *maybe* some sort of Spectroscopy (You can make one with a Raspberry Pi Camera quite easily, or buy a legit one used/that OpenRaman kit) would be very useful! The glassware especially wouldn’t be *too* expensive, and being able to do high quality distillation + bottling on your own would be VERY useful. Having spare Diethyl ether suddenly isn’t such a bad thing!
This is amazing!! I've been wanting to also make the cryogenic cooler thingy, and I've used propane to get around -45°C, but I also couldn't obtain a gas that could act as a second stage refrigerant after propane. Ethylene or ethane would do. I thought of thermal cracking butane to get some, but this ethanol method is much nicer to do. After you've obtained the gas mixture, I think it would be best to compress it to a high enough pressure (20~30 bar) in an ice bath, take the gaseous part of whatever (water, ether) is left after it, and then cool it to an obtainable -30°C to liquefy the ethylene, and extract only the liquid part of it, to get rid of the hydrogen and air ( nitrogen, oxygen ) Pretty much putting the ethylene thru its intended cycle, but doing it in open-loop to get rid of the impurities, especially the water (that can easily clog the system and hydrogen (which could make the liquefaction much harder, lowering the efficiency and the obtainable temp.diference) I expect there to be quite a bit of water if you'd compress it at 20bar and cool to 0°C, and you really don't want that in your capillary tube.
Amazing work! I know a lot of people are suggesting the sulfuric acid route, however that stuff is a huge hassle to work with outside a lab setting, and if you are using less than anhydrous ethanol you're going to end up with a ton of dilute sulfuric acid that needs to be boiled down to be useful again. Believe me that is messy and terrifying, having 300C acid bumping is nightmare fuel and it will always bump to some extent. Just skip it and save yourself the headaches 😊
For that I just recommend doing it on a concrete slab outside with a decent wind. And use alot alot of boiling rocks. Like put in so much you think it's too much. Then double it.
Man glad you made this, theres some ultra low quality video of a guy doing the same but he left out a lot of details that you included. Time for me to break out the alumina I bought a year ago!
Found your channel a couple of days before and watched all of your videos with great pleasure. It's so nice to see someone explaining such complex topics and building real-life working prototypes. Thank you for making videos at such an incredible pace, but please, don't get burnt out from such an overwhelming load. Wish you success in all your experiments and steady growth to your channel. You definitely deserve a million subs at least!
I thoroughly enjoyed this video!! In retirement, I decided to continue-on in a more 'part-time mode', and service/repair post (1 year) warranty Amana PTAC/PTHP wall mount units. They are very well made, however, they do have a few weak points, one being the Zhongshan Broad-Ocean EVAP motor. Always be sure to have a spare hanging around somewhere, as they seem to fail at the most inopportune time.
I think for a better way of controlled heating would be some kind of resistance heater with a PID controller, youd make a heater that would surround the catylyst pipe and the thermocouple would control the heating better than a fire. a way I would think of doing this would be making a open ended tube heater where you can add fire bricks with holes drilled in them for insulation that are the diameter of the catylyst pipe. would be better if you want really precise and even heating.
Where i work, we have several environmental chambers, and they are cascaded. Normally we do -50 to +60c, but i have goofed up and accidentally sent it below -70c, triggering loud annoying alarms. It fascinating watching you work towards the same type system!
100 for the method glad to see a different way to do a dehydration reaction. The method with sulfuric acid is quite simple and is called an acid catalyzed dehydration, this method seems easier if anhydrous sulfuric acid is unavailable
Hello. Mixing ethanol, sulfuric acid and heat you will get some diethylether. Actually it goes like that: Mix ethano and sulfuric acid and start to heat the mix. After some time, there will become dietylether fumes. All the time, when ethanol reduces and chance form to ether, you will have to add more ethanol to the mix. Basicly you would need some chemistry stuff, flask, consender and so on to catch all ether fumes and cool those down to liquid form. It is pretty easy to do diethylether if have all the stuff needed. I havent heard abaut making ethylene with sulfuric acid and ethanol. Only to produce this ether. And thanks for good video, I liked it!
Back when I was in HVAC studies I built a 220v Dual headed, triple stage condensing unit. R490 R508 R1150 as I recall. (not sure about the 508...) Used it a couple times for overclocking runs. I had the Gtx295 quad record for almost a week with it, until Shimano Or KP, volt modded and put theirs under liquid nitrogen to nudge past me.. Its sat ever since. LN was easier and cheaper.
Awesome video- kinda funny to see the combination of "low tech" gatorade bottles with "high tech" custom printed brackets. Thanks for the interesting video and clear explanations!
Very cool. Perhaps using several thermocouples in parallel might give you a better average catalyst temperature. Many year ago I worked as an industrial / petrochemical refrigeration technician and we used to manufacture / commission and often maintain systems we built. One of the systems I used to maintain (wasn’t involved in the construction of it) was a large cascade system with a high temperature screw compressor driven by an 800kw motor running on R22 and the low temperature screw compressor was driven by a 400kw motor, I can’t recall what the low stage refrigerant was but 25+ years ago it was about $300 per kg and came in small cylinders like a nitrogen bottle, the pressure was extremely high and it was kind of scary to charge with. This system was actually part of a flash gas condensing system for Ethylene storage and was the final subcooler before the Ethylene was re injected into a very large storage tank which held liquid ethylene at -100°C, our sub cooler was getting it to about -90°C. This system incorporated a large vessel which had automatic valves which opened to the high side when it shut down and another which opened to the low side during operation, the purpose of this was to limit the maximum off cycle pressure . You might need to consider that the off cycle pressure can be relatively high on cascade systems and may need to do something similar or at least add some additional volume on the low side of your ethylene side
I enjoy projects like this. Nice to see the home creation of products. Overall, this process has it challenges. But, not too many to make difficult to produce.
For heating your catalyst evenly: try making a jacket out of a larger pipe and place your catalyst tube inside and fill the jacket with motor oil. the oil will evenly distribute heat on all sides.
9:22 confused the hell out of me because of how you said it, but I think I understand it if this rewording is accurate: You can see the decrease in water volume by the decrease in weight and knowing water's density, the reason is because the volume of injected gas is equal to the volume of water lost. I suppose the other assumption here is that the weight of the gas is negligible.
I was totally expecting you to use a chemical method to generate your gas. The use of a cracking catalyst was a surprise. Well documented and presented. Bravo At the pressure in your tank, a dry ice bath might help separate out the H2 if any exists
Jeez, I wanted to try something like that for a long time. Great project! 16:25 you may try to liquefy it by combination of dry ice and elevated pressure --- a few bars should be enough. The important part is not to blow the vessel up as it heats back up :)
Love the chemistry calculations. Hydrogen is really good at diffusing right through many solid substances. I'd guess most of your hydrogen will have bled out through the walls of the beach ball, especially over the course of an hour waiting time.
Thought on the heater for the cat. Induction. You can have it heat the unit and with pwm control the power. 17:33 idk if the em would interfere with your thermocouple, perhaps a common mode reject circuit
It took me a while to realize but This is basically the exact process i used at an ethanol plant to get pure booze out. You just cranked the heat up, we even used those same beads in a vacuum sieve
Really impressive video!
Nice seeing you here
Yeah
YES!
Nice
Lol
one thing that absolutely shocks and impresses me about this channel is the pace at which videos are coming out, the last 6 months seems like years worth of work
yea this is nuts
Yeah this guy is going into like Applied Science level depth on this project and just absolutely cranking out the videos. It's nuts. Between the work and video editing, he's gotta be spending like 20 hrs a week minimum to get these out this fast. Insane.
@@helldad4689 Indeed. Much respect to the guy
Culmination of interdisciplinary interests and skills.
Yup. He's in the zone. Amazing and I'm grateful to get to witness it
Absolutely love this video. As someone who got a degree in chemical engineering and therefore spent many, many, MANY hours learning every minute detail of designing and building plug flow reactors, understanding their governing thermodynamic equations, solving differential equations to characterise the fluid dynamics of the packed catalyst beds, understanding the materials science of the various alloys used to build them and the physical chemistry involved with zeolite-catalysed reactions, drilling down into details of details of details I never could have imagined existing before...
It absolutely blew my mind to see someone casually building a packed-bed plug-flow reactor from plumbing parts and unspecified alumina beads in his garage, and the damn thing actually working! Seriously, well done! (Deep down I'm almost insulted by the fact you managed to get a decent yield without doing any equations to work out the reaction rate, and therefore flow rate and reactor length required 😂)
I think your "missing mass" is probably unreacted ethanol and possibly some diethyl ether that makes it past the collector bottle (I'd call that a blowdown drum 😂) and dissolves into the bubbler water and or adsorbs onto your silica gel dessicant. The bubbler will probably catch nearly all the ethanol, and a bit of the ether (particularly as it picks up more ethanol)
The burning of your collected liquid looks to me like it's due mainly to ethanol burning, nice and calm and blue. I'd expect ether to burn off much more excitingly if it were the major component. I suspect a good fraction (half?) of the diethyl ether your reactor produces is ending up in your final product and I would suggest trying to do a thorough job of removing it because it's just such an horrific fire hazard. Although its boiling point is like 35*C, it has an insanely high vapor pressure so most of it will stay as vapor at atmospheric pressure even when cooled below this. Even at 0 degrees its vapor pressure is something like 1/3 of an atmosphere so that's why I suspect you have a lot in your collected product.
Oh, diethyl ether also has a sickening sweet smell, to me that's what it sounded like you were describing.
Oh one more thing (sorry!) - I think your burner design probably needs more outlet holes or a more restrictive venturi inlet to work as intended. Looks like the flow in the pipe is stagnating because the outlet resistance is too much, so the pressure in the pipe matches the atmospheric pressure and the venturi can't draw in air.
That said it might be for the best because it seems to do the job well enough, and unless you're quite careful with the nozzle design, there's nothing to stop the flame front moving inside the pipe if the mixture inside it is flammable. You can pack the pipe with some sort of metal mesh to mitigate this but obviously that creates a lot more resistance to the flow.
Any idea how I could calculate the change in temperature in a PFR? Not something complicated, just a simple 1D-model (so everything symmetrical essentially) with a fluid flowing through a packed bed, resulting in a reaction given pressure and temperature. But this releases reaction heat, which is then not just spread within the bed (lets call it conduction) but is also transported along the PFR with the fluid. So the next section of the PFR sees a hotter fluid, which means faster reaction, so more heat, so section 3 gets even hotter etc.
I have a python model with the reaction and everything, but how to calculate dT/dz (z = lenght)? Sorry for this random question, but I dont exactly often run into other chemical engineers that do things like that. I deal with rotary kilns normally, hence most of the things are known. But in a rotary kiln the fluid does not pass through the solid, so this side of things is, sadly, unknown to me. But I want to get a simulation running to prove (or disprove) something I once told a client... just a gut feeling, but it seems to make sense (that the heat can accumulate and cause issues). And yes, I know that this can happen in PFR with calatysts (have seen ex-molten catalyst in a ammonia reactor), but in this case it is a ad/desorption (for regeneration) or a Cu-Zeolith, so things are somewhat different.
Great info!
A curiosity: does this reaction equilibriate much? -- would excess H2O shift the balance in favor of ethanol or diethyl ether? (Also for reference, what's the equilibrium constant at ~1atm?) Is diethyl ether dissociated to ethylene on further heating?
Seems possible the flow rate is too high, causing uneven temperatures (lower at the inlet, and in the center of the catalyst fill) as well as not having enough dwell time for reaction.
Hmm, excess diethyl ether vapor should condense at the bottom of the pressure vessel, for the same reason water does (when compressing atmosphere). Not as much, relatively speaking, of course, but it should be at least diagnostic.
@@T3sl4 The reverse reaction, ethanol via hydration of ethene, is how a lot of industrial ethanol is produced. So that equilibrium will absolutely be shifted to ethanol with more water. The direction you take is endothermic, so heating helps both with reaction rate and conversion. The endothermic nature of the reaction actively helps reducing the temperature gradient in your reactor. However, getting a really isothermic reactor is essentially impossible. Even without any reactions happening, just moving a fluid through the reactor and ignoring radial gradients, you would have to adjust the heating along the length very carefully to get somewhat close.
The equilibrium is highly temperature dependant, so I am not sure if one value would help you much. There are lots of papers on this... if you really want to dive into this and make some simulations.
In any way, given your success, you dont need to waste any time on any of this. It works super good already. It is not like ethanol is expensive or you need scale production up 100x.
You are not going to condense ether like that. It is mixed with ethylene, lowering the partial pressure. You would need very low temperatures to get most of it out of the stream. However, that would be a good idea as a step between the bubbler and the desiccant: Cooling it to... say -20 °C.
And yes, for the same reason water condenses the ether will too once the pressure is high enough, since the partial pressure goes up too.
Dietary supplement for sea turtles f**king savage.
That he says it so deadpan is perfect!
And it’s actually a good food source - algae grows rapidly on the plastic particles which is not toxic to sea turtles…
Large sheets or ropes of plastic (like fishing nets and six packs rings) do block their digestion however…
@@allangibson8494 did you just argue in favor of-- You know what. Never mind. Next video.
@@CriticoolHit A good food source, perhaps; a healthy food source, well see, that's another matter!
@@T3sl4 Its got electrolytes its what turtles crave...
For your calculations, the mass you distilled from the flask of everclear wouldn't be 100% ethanol because ethanol and water form an azeotrope. A mixture of 8% water and 92% ethanol has the lowest boiling point, so that was probably what you distilled over. Making your own ethene is astounding. Impressive yield.
The azeotrope is actually 96.4% I believe
@@rollei35mm uhm ackshually 🤓🤓
@@wazaagbreak-head6039 I don't study chemistry to not be insufferable, hahaha
@@rollei35mm yeah from my home um "experiments"... Can confirm
96% lol
@@wazaagbreak-head6039 How do you mess that up. Like seriously, how? There's so many places where you could type that comment and be funny, yet you picked the one place where it makes *YOU* become the joke. That's honestly impressive, but not in a good way.
As an (Bio-) Petrochemical AND Open Source Hardware nerd who wants to be able to make like *all the things* at a community/makerspace scale, this is AMAZING!
Granted may need to be modified etc, and some things require larger scale (i wrote some wiki page on this), but having this chemical at this scale is an amazing addition to the toolkit!
Really neat video, keep up the great work!
💀
Mee too
Wow, this is awesome! One thing that might improve your yield is actually pre-heating the ethanol vapor. It's hitting the catalyst at ~100C, so it takes the first few inches in the catalyst bed to actually get it up to 450C, so you're running with low selectivity on the first bit of the reactor. You could accomplish this by filling the first several inches with an inert material with a high thermal capacity to get the ethanol up to temperature so when it hits the catalyst it's at your target temp. Broken/ground glass should do the trick if you don't want anything fancy!
Sir, I admire your pirate attitude. Can't be any freeer as a person than when you take simple chemistry and apply it carefully to obtain difficult to get components. Your thoroughness in calculating yields and identifying by products are a testament to your interest in handling this stuff safely. I want to be like you when I grow up.
It isn’t difficult to get, it’s just marked up so much by corporate greed.
@@Preinstallable I agree but also disagree, since something being marked up to prohibitive levels is the definition of difficult to get. For the average person, when they see their options of "shell out for "store-bought" ethylene" or "build your own packed-bed plug-flow reactor", they're probably going to mentally file that under "difficult to get".
@@JohnDoeWasntTaken Fair enough. Difficult to avoid paying exorbitant prices for.
As a refrigeration mechanic I love the content and interesting take on all this.
I’m currently sourcing all the parts I need for a cascade system..
Keep up the great content 👍
I worked for a rural HVAC company for 23yrs, and my boss passed away, so I took over. I'd been putting off my EPA test for 18yrs. I studied for two weekends, paid the $50 and passed it. It's an easy test, and the license is forever.
Oooh what's the test called? Maybe I'll study and take it just for shits!
As a researcher working in steam reformation you absolutely nailed it. Gas heated reactors can be very hard to tune and can give all sorts of weird results due to the larger temperature gradients. The second batch also looks like you may have started reforming. The water gets used in the water gas shift reaction to make H2 and CO2.
Very cool video! I suspect that the liquid you collected after passing the ethanol over the catalyst is mostly a mixture of water and unreacted ethanol. Diethyl ether is immiscible with water, and only slightly soluble, so you would expect to see a separate layer if an appreciable quantity of ether was produced. Ethanol is also less dense than water, but fully miscible with water, so this may explain the lower density of the mixture. A lower concentration ethanol/water mixture isn't super flammable though, so you may be right that there is a little bit of diethyl ether dissolved in the water which caused the mixture to ignite. If you distilled the mixture to determine the composition, I suspect you'd find that it is mostly unreacted ethanol and water. I'm excited to see you use the ethylene as a refrigerant and look forward to that video! Great job.
Would be nice to se it fractionally distilled, just for the science.
in my experience it smells more than diethyl ether and something else, and not like ethanol at all. also it can be oily and stick to the bubbler - so I hope you got your dog a new bowl.
Could ethanol contamination allow ether to become missable in the aqueous solution?
@@garbleduser ooh, very possible. Ethanol and ether are miscible. I agree that fractional distillation would be nice just to see what the composition is.
My IQ is for sure too low to speculate but maybe because of the way he heated the catalyst he had a range of temperatures at different places. Maybe a more consistent way to control temperature throughout the catalyst might help. Again I may not even be making sense I definitely am not even a novice.
I’ve been following this closely. I do HVAC Service for work, and have played with my own R290/Propane system before that had great results. I built my own tiny little system from scrap Dehumidifier parts, and I’ve also used it in a Window AC for shiggles. Both worked great! I’ve got so many random parts, this project seems like something I should try myself!
I also have a small collection of old refrigerators. I have a GE DR1 Monitor Top which is the “first” electric home fridge. It uses SO2 as refrigerant and that stuff is nasty. I do not want another whiff of that. I had to dispose of that with a bit of simple chemistry, and the perfect replacement refrigerant for the thing is R152A aka Air Duster cans! I ended up having to fix a leak in the bottom of the compressor, and I’ve had it sitting with 150psi of nitrogen in it for probably 6 months now. Can’t wait to fill it up again and get it cooling
Been watching this channel for a while but this project has made this my all time favorite channel. I've wanted to make a cryocooler for a while now and the amount of information with detailed explanation of the build and data analysis is GOLD. Can't wait till you get your first drop of cryogenic liquid!
Bro this is my favorite TH-cam series so far. Can’t wait for the next episode!
I wish my chemistry teachers had been half as interesting as you.
Ether as a byproduct? This reaction keeps getting better!
"There is nothing more hopeless and depraved as a man on an ether binge."
@@captainotto I dunno about “nothing more” but yes it gets pretty depraved lmao. Feeling like a solvent plant definitely doesn’t help
Edit: err, reeking. Not feeling. Well, that too I guess!
@@mduckernz Hunter S. Thompson - Fear and Loathing in Las Vegas
But even if you read the book or saw the movie, you can't be blamed for missing it because I butchered the hell out of the quote and failed to attribute it.
Cool, thanks for video. There are also "autocascade" phase-change systems, using mix of different refrigerants while using the same compressor in system. Polycold is (was?) one of the famous manufacturers of such systems for industrial use. You still need oil separator, compatible refrigerants and some heat exchangers for system to work, but at least don't need additional compressor. Oil separator is needed for reaching low temperatures, otherwise it will freeze up and clog the capillary tube restriction.
It is a lot of cold storage brands out there, mainly running at -152C.
Using auto cascade as you mention, but very few use a single stage system.
The first stage pre-cool the auto cascade second stage system.
Horrible pressure even with two stage due to the high pressure gases time to reach a condensation temperature.
Often two oil separator in series and capillary tube heaters kicking in on cycle off periods by a timer to clean oil off the tubes.
Very expensive gas mixtures on them with critically share of the gas un the mixed blend and the total amount.
I always wanted to do this exact process for TH-cam for the same purpose, I'm glad someone beat me to it!
You know its good when it takes an hour to watch 18minutes. So much invention , so much Science, its inspiring. The problem solving with modern day off the shelf parts is as impressive as the calculations. The numbers dont need to be exact, its the method which is demonstrated that hopefully leads to understanding in such a way that it is raw , Kg,m,s . Impressed by the whole project at every stage.
smell-test is not a great thing for cancerogenic anesthetic, but it works. I've made ethylene with the same method in lab, with just a butane torch heating it. FTIR showed almost complete conversion and MS showed lots of ethanol with the gas. your cleaning steps are very nice. i did run my catalyst in quartz tube, so i could eyeball the yellowing of the catalyst, and ethanol I evaporated in the same quartz tube from mineral wool. but I did not need 60 liters. Good Luck!
Nothing is carcinogenic here
@@Exotic_Chem_Lab I wouldn't be so sure, maybe the OP is in California?
There is no evidence for carcinogenicity of diethyl ether, and no reproductive effects have been reported. Chronic exposure to diethyl ether vapor may lead to loss of appetite, exhaustion, drowsiness, dizziness, and other cns effects.
the EPA 608 is super simple to get, you basically just have to be able to read. thanks for taking the time to explain it
I am so envious of your motivation to start and then work on and then complete such a long involved experiment and film it at the same time. Once again I can only say thank you.
This is the best experiment series on youtube, i cannot wait to see your next cooler design and to really get those low temps
This is really interesting since a way of creating ethylene that I'm familiar with (and you kinda hinted at it in the beginning) is using sulfuric acid, the entire reaction uses sulfuric acid heated to 180°C:
Ethanol ---(H2SO4 @ 180°C)---> ethylene + water
you can see the benefits of that since it requires a much lower temperature that the method you used.
Interestingly enough you could also use the same setup but at 140°C to make ethers as well and I think Neilred used it to make diethyl ether from ethanol quite a while back.
I'd be really wary of using the sulfuric acid method because it's also very likely to generate some amount of diethyl sulfate, which is a strong alkylating agent. Very toxic, very carcinogenic, very very nasty.
@@jhonbus Good call. Apparently diethyl sulfate can be made by bubbling ethylene gas into hot, concentrated sulfuric acid so this really is a valid concern.
I was going to mention this. I've used this plenty of times with various alcohols (think I managed acetylene from 1,2-propadiol with a peroxide kick once) and it's got so many advantages on laboratory scale. You just need a flask, a heat source, and sulfuric acid; they only need be good enough quality to get the job done; and you can use all of the components for whatever else you want if you're satisfied with your alkyne gas situation because there's no special apparatus.
PS: yes the sulfate ester byproducts are carcinogenic as hell they're alkylating agents, if you're collecting the alkene gas you're making for non immediate use or making enough that alcohol addition dropwise is too slow, you need to run the output through alkali before getting your mortal, cancer vulnerable fingies near it.
As a refrigeration mechanic by trade i love this stuff. As a professional pyrotechnition i love it ecen more. As an apprentice i worked on a ultracold bone cabinet it ran a R502 cascade system to a R503. We added ethelene to prevent waxing and capillary freeze up blockages. Our target temp was around -82deg c. The power bill was bad for just 2 weeks run time. All the same great content
I love how clear and concise your explanations are. Nerdy science stuff is awesome. :D
having a flammable refrigerant is literally killing fire with fire...
brilliant
Math skills, hand skills, and strong problem solving. You are an impressive human, appreciate you sharing your world with us.
Bro I don't understand a word that's that but I love watching this series.
I've seen plenty of DIY chemistry, but I think this is the first time I've seen DIY chemical engineering
I like the editing especially the Minecraf joke.
Greatest knowledgeable videos ever۔۔۔۔❤
Just a couple of thoughts from a chemist... Crush the catalyst beads for more surface area, better conversion. Ether is soluble in water to around 6% w/w so you should see a phase separation at any higher than that if theres no ethanol in the mix. You can break the water-ethanol azeotrope by adding a ternary solvent but whats the point, your byproduct is water. The major difference between what you did and the sulfuric acid dehydration route, from an engineering perspective, is continuous vs batch process. Play with the residence time of your ethanol vapor on the catalyst bed to increase yields even more and run it vertically for better mixing. Anyways, good job, enjoyed watching this!
Subscribed when I saw the thumbnail... No regrets.
great video series! thank you for taking the time to put together these videos.
I'm so desperate for the next video, that I'm watching this a second time now.
I’m impressed. Your engineering , chemical and mechanical are truly spot on.
thanks man, after watching many of your videos I feel like real ice wizard
So happy I found this channel! Very cool project, narrated at a pace that keeps you 100% focused with no fluff. Wish I could give more than one thumbs up!
First of all: You make absolute premium content for fellow educated nerds! ;)
A hint on the yield: try to use pure 100% ethanol, dried with molecular sieves. It will increase the yield as you don't add water in what also is a waste product. All the reactions are equilibrium reactions. That tend towards a certain composition. Less water in will mean more water (and thus ethene) produced as the output gas stream will try to converge on the same composition, given the same conditions.
I’m obsessed with this project! Can’t wait for the finale!!
Love this. I was building a cascade system just like this about 15 years ago. I wasn't able to find a source of ethylene. Before I got that far, I got a severe frost bite on both hands from a propane leak in the first stage. I wasn't able to use my hands for 2 weeks. Be careful!
That shot of your 2 stage system, caught my eye.
Early last summer, our AC started leaking R 22
out of it. Compressor was leaking. So, I started
running R 290 in it. (Well, not refrigerant grade,
but BBQ grade.) One bottle lasted all summer,
and the landlord was able to find a replacement
unit MUCH cheaper, out of our "warm" season
Phoenix Az.
Bought a weedburner from Horror Fright, cut
the line, cut a line on my cheap set of AC
gauges, and shot some R 290 in. Left the tank
and gauges under the AC, so I wouldn't be carrying
them up and down. At least once a week, or more
often.
steve
As an HVAC EPA Certified tech for diesel truck refrigerator trailers, i thoroughly enjoy this! I can probably get a high output 1994 unit for 1200.00 USD at LKQ... that's actually not a bad idea come to think of it... Some of those units use the R508, so if you had the opportunity, one could theoretically find a place that is decommissioning the retired units and offer a free service to recycle/dispose of the refrigerant for the yard, and then collect enough of what you need as well. Granted not everyone has a recovery system that can store used Freon, i get that.... Just a thought.
A truly engineering approach to the task! Beautifully done!
Brilliant work! Keep it up, I could watch these all afternoon
I love deep dives like this. Definitely unique methods.
Always wonderful
I wish you this forever💪
Depending on if the ethanol dehydration is endo or exothermic, this might also be affecting your catalyst temperature profile. Love your work!
Your videos are very educational with a hint of entertainment, I look forward to singed eyebrows from knowledge gained here😁
I want to subscribe, but I feel like it’ll get me placed on some kinda watch list. Ehh, what the hell. These videos are worth it.
Dude, thats dope. I got a old two stage system that needs a refill.
Cool video, fyi in your last video you had a heat exchanger, if you reverse the flow on one side you'll increase your effciency using contraflow cooling which uses "warm" coolant to pre-cool the "hot" coolant and cold coolant to chill the "warm(previously hot coolant)" down could gain you a few % in effciency for a change of plumbing
I think you are a genius. Just one an advice. To identify a gas is very easy. Just measure density with the help of the proper syringe, divide this by the density of hydrogen gas at the same pressure and temperature, multiplied by two; that is the molecular weight of the title gas.
Neat stuff. I’m a commercial refrigeration tech myself. When I first got into the trade we did some work for a lab experimenting space tiles. Similar setup to what you are making in terms of one refrigeration system cooling the condensor of another
Loving your graphics and editing, btw. The style jives well with your deadpan without getting in the way of clarity.
Love this content so much and your dry sense of humour.
Granted *Money* but having a good hit of basic Glassware, and *maybe* some sort of Spectroscopy (You can make one with a Raspberry Pi Camera quite easily, or buy a legit one used/that OpenRaman kit) would be very useful!
The glassware especially wouldn’t be *too* expensive, and being able to do high quality distillation + bottling on your own would be VERY useful.
Having spare Diethyl ether suddenly isn’t such a bad thing!
This is amazing!!
I've been wanting to also make the cryogenic cooler thingy, and I've used propane to get around -45°C, but I also couldn't obtain a gas that could act as a second stage refrigerant after propane. Ethylene or ethane would do.
I thought of thermal cracking butane to get some, but this ethanol method is much nicer to do.
After you've obtained the gas mixture, I think it would be best to compress it to a high enough pressure (20~30 bar) in an ice bath, take the gaseous part of whatever (water, ether) is left after it, and then cool it to an obtainable -30°C to liquefy the ethylene, and extract only the liquid part of it, to get rid of the hydrogen and air ( nitrogen, oxygen )
Pretty much putting the ethylene thru its intended cycle, but doing it in open-loop to get rid of the impurities, especially the water (that can easily clog the system and hydrogen (which could make the liquefaction much harder, lowering the efficiency and the obtainable temp.diference)
I expect there to be quite a bit of water if you'd compress it at 20bar and cool to 0°C, and you really don't want that in your capillary tube.
Amazing work! I know a lot of people are suggesting the sulfuric acid route, however that stuff is a huge hassle to work with outside a lab setting, and if you are using less than anhydrous ethanol you're going to end up with a ton of dilute sulfuric acid that needs to be boiled down to be useful again. Believe me that is messy and terrifying, having 300C acid bumping is nightmare fuel and it will always bump to some extent. Just skip it and save yourself the headaches 😊
For that I just recommend doing it on a concrete slab outside with a decent wind. And use alot alot of boiling rocks. Like put in so much you think it's too much. Then double it.
Man glad you made this, theres some ultra low quality video of a guy doing the same but he left out a lot of details that you included. Time for me to break out the alumina I bought a year ago!
Found your channel a couple of days before and watched all of your videos with great pleasure. It's so nice to see someone explaining such complex topics and building real-life working prototypes. Thank you for making videos at such an incredible pace, but please, don't get burnt out from such an overwhelming load. Wish you success in all your experiments and steady growth to your channel. You definitely deserve a million subs at least!
I thumbs up for the thumbtag alone
I thoroughly enjoyed this video!! In retirement, I decided to continue-on in a more 'part-time mode', and service/repair post (1 year) warranty Amana PTAC/PTHP wall mount units. They are very well made, however, they do have a few weak points, one being the Zhongshan Broad-Ocean EVAP motor. Always be sure to have a spare hanging around somewhere, as they seem to fail at the most inopportune time.
I think for a better way of controlled heating would be some kind of resistance heater with a PID controller, youd make a heater that would surround the catylyst pipe and the thermocouple would control the heating better than a fire. a way I would think of doing this would be making a open ended tube heater where you can add fire bricks with holes drilled in them for insulation that are the diameter of the catylyst pipe. would be better if you want really precise and even heating.
Dude... just... big respect!
Where i work, we have several environmental chambers, and they are cascaded. Normally we do -50 to +60c, but i have goofed up and accidentally sent it below -70c, triggering loud annoying alarms. It fascinating watching you work towards the same type system!
YOU MAKE SOMETHING SO EASY EXTREMELY COMPLEX. JESSH!
100 for the method glad to see a different way to do a dehydration reaction. The method with sulfuric acid is quite simple and is called an acid catalyzed dehydration, this method seems easier if anhydrous sulfuric acid is unavailable
this is cool asf. i’m here for the long run man. you got it!
congrats on your ethylene creation. love the videos! keep them coming
Hello. Mixing ethanol, sulfuric acid and heat you will get some diethylether. Actually it goes like that: Mix ethano and sulfuric acid and start to heat the mix. After some time, there will become dietylether fumes. All the time, when ethanol reduces and chance form to ether, you will have to add more ethanol to the mix. Basicly you would need some chemistry stuff, flask, consender and so on to catch all ether fumes and cool those down to liquid form. It is pretty easy to do diethylether if have all the stuff needed. I havent heard abaut making ethylene with sulfuric acid and ethanol. Only to produce this ether. And thanks for good video, I liked it!
using animations in the video is a nice addition
Back when I was in HVAC studies I built a 220v Dual headed, triple stage condensing unit. R490 R508 R1150 as I recall. (not sure about the 508...)
Used it a couple times for overclocking runs. I had the Gtx295 quad record for almost a week with it, until Shimano Or KP, volt modded and put theirs under liquid nitrogen to nudge past me.. Its sat ever since. LN was easier and cheaper.
Awesome video- kinda funny to see the combination of "low tech" gatorade bottles with "high tech" custom printed brackets.
Thanks for the interesting video and clear explanations!
I love that gasometer!😊
Very cool. Perhaps using several thermocouples in parallel might give you a better average catalyst temperature.
Many year ago I worked as an industrial / petrochemical refrigeration technician and we used to manufacture / commission and often maintain systems we built. One of the systems I used to maintain (wasn’t involved in the construction of it) was a large cascade system with a high temperature screw compressor driven by an 800kw motor running on R22 and the low temperature screw compressor was driven by a 400kw motor, I can’t recall what the low stage refrigerant was but 25+ years ago it was about $300 per kg and came in small cylinders like a nitrogen bottle, the pressure was extremely high and it was kind of scary to charge with. This system was actually part of a flash gas condensing system for Ethylene storage and was the final subcooler before the Ethylene was re injected into a very large storage tank which held liquid ethylene at -100°C, our sub cooler was getting it to about -90°C.
This system incorporated a large vessel which had automatic valves which opened to the high side when it shut down and another which opened to the low side during operation, the purpose of this was to limit the maximum off cycle pressure . You might need to consider that the off cycle pressure can be relatively high on cascade systems and may need to do something similar or at least add some additional volume on the low side of your ethylene side
Superb analysis of process. Good science! Thanks
Very cool. It worked and didn't blow up. A+
I enjoy projects like this. Nice to see the home creation of products. Overall, this process has it challenges. But, not too many to make difficult to produce.
nice video we passionately await submarine kayak 2 thanks liov u
Happy fun stuff I don't understand at all time
I can’t hardly wait for the next video.
For heating your catalyst evenly: try making a jacket out of a larger pipe and place your catalyst tube inside and fill the jacket with motor oil. the oil will evenly distribute heat on all sides.
You are my favorite new nerdy TH-camr
Nifty ! Even though I know very little about chemistry I'm sure enjoying this series.
9:22 confused the hell out of me because of how you said it, but I think I understand it if this rewording is accurate:
You can see the decrease in water volume by the decrease in weight and knowing water's density, the reason is because the volume of injected gas is equal to the volume of water lost.
I suppose the other assumption here is that the weight of the gas is negligible.
I was totally expecting you to use a chemical method to generate your gas. The use of a cracking catalyst was a surprise. Well documented and presented. Bravo
At the pressure in your tank, a dry ice bath might help separate out the H2 if any exists
Jeez, I wanted to try something like that for a long time.
Great project!
16:25 you may try to liquefy it by combination of dry ice and elevated pressure --- a few bars should be enough. The important part is not to blow the vessel up as it heats back up :)
Love the chemistry calculations. Hydrogen is really good at diffusing right through many solid substances. I'd guess most of your hydrogen will have bled out through the walls of the beach ball, especially over the course of an hour waiting time.
Amazing work and very well presented. Thank you.
best channel on TH-cam
Thought on the heater for the cat. Induction. You can have it heat the unit and with pwm control the power. 17:33 idk if the em would interfere with your thermocouple, perhaps a common mode reject circuit
hell yeah. This is super interesting stuff. you've convinced me to start fucking around with DIY refrigeration.
It took me a while to realize but
This is basically the exact process i used at an ethanol plant to get pure booze out. You just cranked the heat up, we even used those same beads in a vacuum sieve
This channel is amazing! Nice work!
I don't know how many people need ethylene but you should be producing it and selling it
I appreciate u sharing this with us, love these videos.
I absolutely love this guy