I worked in the R&D Department of a pharmaceutical company and we used the "feed through line" as a way to use the vacuum to pump in fresh material when product concentrations were low and volumes were high. This way you don't have to disable vacuum every time to refill the flask. Just wanted to tell this as an additional function of this part. I also wanted to let you know that i was perfectly able to disassemble, deep clean and reassemble this as a intern undergraduate ;)
I'm glad you're getting to enjoy to daily drive a rotovap! I'm one of these lab techs you were talking about in your introduction, who rely on rotovaps daily for their lab scale production processes; we're making ruthenium- and biotin-labelled peptides which are used as analysis reagents for the elecsys diagnostic system. A neat tip about the gas-feedthrough tube you were talking about at 11:28 - you can also use it to add more solution to be evaporated, if you're working with big batches. Just attach tubing you're dropping into your bulk container to the vent valve, this way you can open the valve every now and then a little and the vacuum sucks additional solution into your distilling flask. Have fun with your new tool; I'm excited to see it included in your upcoming videos.
Wow! i'm learning new stuff everyday, i never thought to use the gas feed through tube to also feed product into rotovap. Most of the labs i worked in had broken/missing tubes so it wouldn't have worked, so i never thought of it. This is why i love posting these equipment videos, you guys teach me new things!
Tygon tubing leaches plasticizer (was phthalate; there's some kind of grotesque citrate coming up) into a solvent stream. See what you can do with fluorinated polymer tubing..
Yeah, my Buchi RotoVap-T has a feed tube that goes all the way through into the rotating flask. also. They're hard to find on the surplus market and easily broken.
I've used aqua regia a handful of times, only at small scales to display in classes for gold recovery. To hear you casually mention it as a cleaning agent...it makes sense, but it hurt my brain. I need more chemistry in my life. I keep telling my nieces and nephews who love fantasy stories: "Do you really want magic in the real world? Chemistry is as close as you'll get."
Absolutely. I'm not a professional chemist and I've never studied it at degree level, but I love the gear. The actual chemistry goes way over my head, but I know just about enough not to be dangerous. It's mostly just adding acids and/or bases to things, then filtering or distilling. Obviously there's more to it than that, but that's for the proper chemists to do.
@@igotes The workup is what you are describing. So yeah, you have [acidifactions/basifications/extractions/recrystallizations/distillations/filtrations/dryings] sandwiching each of the "real" synthesis steps, where some specific reaction might be utilized. BUT those "real" reactions are super challenging to even comprehend for many people. Even among chemists with degrees, lots of us just don't go there in our professional careers because there are many other things to specialize in other than synthesis.
Dude, what a treat. And the fact that it's a gift (not something exchanged for promotion) shows that the lab feels confident enough with its product to know that 1) you'd review it anyway, and 2) the review would be positive. Both already hint that it's a quality product.
Props to that company, you're channel is a bastion for introducing people to some nifty chemistry done in a competent manner at an accessible level I'm glad to see you getting some love.
Does this mean you'll be back more frequently? (Please?) Also, an idea: capsaicin extraction? (the condensing portion?) It would work well for this machine and I think it might be a good way to break it in without messing it up too much (IDK for sure though, obviously 😅)
I'm so happy companies realize gifts like this are nothing but good for them as it inspires young people to get into chemistry as well as getting their product out there to professionals that watch this content.
ROTO-vaps truly are one of my favorite pieces of lab equipment and were one of the most life-changing realizations I had about how much more convenient it was to synthesize products in a professional lab than a home lab.
The OG chemtuber has returned! I am really stoked to see what kind of projects you will do with this thing. Really cool from GWSI Labs to git you that. Have a nice day.
I used to use dichloromethane and cyclohexane with our rotovap while at college for my undergrad work. We would then take the mixture and separate the dcm and cyclohexane in a recycler. It was pretty fun work.
Keep in mind that the cover serves more than just to limit evaporative losses; it moreso is for protecting the lab and the chemist from shards of glass when a flask implodes due to the low pressure. It can happen to flasks that look perfectly fine, but because there is a very fine hairline crack which is very hard to see the flask cant withstand the pressure difference (delta p for all diving accident enthusiasts). Always wear glasses when using vacuum!
Most modern borosilicate glass will usually just crack and break as chunks, usually around the glass welds on joints like the 24/40 adapter. It’s not commonly used, but tempered glass is what will implode much more violently.
I've always wanted to design and build an open-source rotovap. They aren't THAT complex. The rotary joint is the hard part. Upvote if you'd like to see a video about that.
If you use glassware with wheaton clear seal joints the friction of the rotating joint will be less than ground joints and you are likely not going to get ground glass contamination in your product if any.
Your video inspired me to sort through my lab boxes of lab equipment after my last move, and I retrieved and reassembled my Buchi Rotovap-R after five years. I assembled it by buying pieces on surplus market over a period of eight years, and now I have a fully operational unit - no lift, just lab jack under the water bath. My water bath is a 4L aluminium ether bottle, cut in half ( got a big wide-mouth funnel out of it, too!) you aren't the only underfunded chemist out there. My PhD was in terpene synthesis - emphasis on steroids. Good luck to you, and I really appreciate all the good work - especially the "failures" - saves me those months of work!!! I wish there was a "Journal of failed Research."
Good to see a new nurdrage video. Rotovaps are so expensive, I've thought of trying to build a basic one. Those lab suction machines are good, I found one once and used it for a long time until it lost it's suction
Chinese rotos are very cheap these days, You can get a 5L with everything needed for $800-1200. Always get a 5L over a 2L, 2L hot baths can only do a 3L flask at most.
A really great video, as always You can also use the "gas inlet" as a way to put more product into the boiling flask. Also, I think it would be more optimal to put the vacuum line on top, so in case of a bumping, there would be a smaller chance of the vacuum pump sucking in the product. You can also clean your rotavap by replacing the recieving flash with a really small one, filling the boiling flash with a solvent of you choice and letting the solvent drip back into the boiling flask after it fills up the revieving flask.
oh wow, i never thought of using the gas inlet to feed in more product. Then again i never worked on that scale to need it, but it seems so obvious! As for the vacuum line position, it can't be seen, but the there is tube that actually goes up the middle of the condenser to feed the vacuum at the top and at the center. The glassblower even took the time to make the hole aim to the side so it's VERY hard for bumped solvent to get sucked in. This was a well-designed piece of equipment.
Having worked with a rotovap for mushroom polysaccharide extraction, I'm so happy for you! This is an amazing gift, and you're definitely a trustworthy source in terms of putting this baby to good use!
Thats so awesome somebody just sent you a rotovap. I'd so love to have one, but I'll never get close to having that kind of spare money. Expensive hobby
I am excited to see what products you will be distilling. I’m sure you can find some amateur chemistry projects that are still useful. You can just explain that we don’t have to use a rotovap but you did because you have it and it saved you time 😁😎
Congrats on getting your own Rotovap! Another cool way to use it is in crystallizations. 😍 Tumbling and cooling slowly (just by turning off the heating of the rotovap bath) seem to greatly benefit crystal growth, at least in my experience as a natural product chemist. Good vid as always. Take care!
Ooh, I suppose you could use that feed tube to hold a seed crystal suspended in the solution. Heck, you could probably make an adapter to sit on the end, holding the seed crystal and still allow you to add solution to the flask.
Oh wow, I've always wanted to see how these work. I briefly saw one when I visited a university lab a long time ago, but didn't really know what I was looking at.
You can clean a condenser quickly if you use a 2 necked round bottom flask. Connect one neck and cover the other with your hand. Build up the pressure and then you can shoot a cleaning solvent like acetone up into it, although it might not reach the top of a large condenser. Also, you can stop the condser from getting contaminated by using a glass trap, not sure how much they cost but very worth getting a g good one.
A few comments from someone who works in a non-GMP academic organic chemistry lab. 1) We never grease the joint that the flask connects to (don't want grease in your NMR spectra); 2) We always use a bump trap between the flask and the rotavap; 3) The simplest way to do a routine rough cleaning is by using a two-necked RBF filled with acetone, where you apply vacuum while covering the extra neck and then let air in to make the solvent "swoosh" up into the condenser, and repeat a few times. 4) The Büchi 20/40/60 rule is useful for knowing approximately which settings to use for which solvents. Obviously everyone and every lab will have their own preferences, so I'm not saying this is how it "should" be done.
The "gas feed though tube" is also useful for loading additional solution for evaporating with out stooping the setup so larger volumes can be recovered/concentrated
If you need a cheap chiller have a chat with a pub to see if they have a spare drinks chiller. Many drinks chillers are basically a refrigerator hooked up to a water bath. The drinks pass through a stainless coil in the water. They won't generally go below freezing but they get pretty close, especially if you play with the thermostat.
O nerd rage In a way it’s nice how irregular you post because I forget about you then when I remember I get a bunch of new videos to watch thanks for what you do
Constant Temperature Chiller Units typically work by running the refrigeration full blast while pulsing the heating coils to balance the temperature. By way of Putting the cooling and heating systems fighting against each other the unit offers exquisite control of the final temperature.
Rotovap cleaning hack: While assembled, put a 2-necked flask with solvent (acetone) on, turn on the vacuum, and put your hand over the flasks other neck. Once the vacuum gets strong, remove your hand quickly, and watch as the solvent sprays through the entire rotovap and into the solvent receiver flask. Doing that a few times is usually as much cleaning as is needed!
getting flashbacks from undergrad classes... as the rotovaps were only used for teaching, most of the devices had algae growing in the condenser and unknown, likely unpleasant substances splattered over the outside.
I used one that looked quite similar to the model you received and it worked just as well if not better than the 2nd hand buchi that cost just as much and was missing parts for the controller
the gas inlet tube can also be used to recharge the boiling flask when processing bulk solvent without having to shut her down and brake vac. All you have to do is attach a hose between the gas inlet valve and container of unprocessed solvent. Then open the gas Inlet valve and the vacuum will draw solvent up into the gas Inlet tube and down into boiling flask thereby refilling it.
The nervetoxin joke reminded me of my last lab job... We moved into a laboratory that was previously used for pesticide research. It was... interesting... and don't get me started on the sinks/drains... :)
When we had an accident with the rotavap, we would just use an "L" shaped adapter, fill it with acetone, close it off with our thumb and flash a few doses of acetone through a couple of times. Of course better to do this fairly quickly so you don't have anything dried into the glass or something. Breaking the whole thing down seems a bit elaborate...
Given the layout of the condenser, another possible cleaning procedure would be to leave it upright and use the vacuum port as an inlet to spray your chosen series of cleaning solutions up at the top of the condenser and all over the coils.
