For anyone just watching this video; To handle fine heavy precipitates like this, you optimally need a bucket rotor centrifuge that can carry some 250 mL capped plastic centrifuge tubes. A smaller centrifuge for test tubes will also work at smaller scale with more labor, but might be more readily available. These heavy precipitates spin down very quickly into a hard pellet leaving a clear solution behind. Several spins, rinses with vigorous shaking, and repeat cycles will clean up the product very nicely. You can also use a proportionately large volume of rinse water on the order of 10x volume, and allow gravity settling, followed by decanting, with multiple cycles. Some heavy precipitates can be grain refined (recrystallized) into coarser precipitates by gently boiling or cooking in water under reflux for an extended time. (I know Doug hasn't posted anything for 4 years.)

Thanks for taking the time to film and talk through that water bath and pie plate technique. Simple, "boring," but incredibly useful things like that have a way of getting skipped over sometimes.

Excellent ! I've been trying to find a good video on this catalyst for a while

Awesome new video, Doug! Keep it up :-)

Thanks, nice explanation throughout the video, keep doing what you're doing.

Great video! Keep up the good work!!

Thank you Doug! 😁

I picked up a niced vacuum oven at a surplus place - someone had been using it ti degas epoxy, and run resin all over the racks and floor. I used LN2 to embrittle the epoxy and broike off all the resin, then sand blasted to get the lassdt dregs and presto - nonm-ruijed vacuum onen.

Dude! Good job!

Thank you so much

Beautiful lab setup you have! Pretty amazed by the ingenuity of the ghetto drying of the paste!

Holy shit dude I'd never even thought of buying an IR thermometer.

The colors are so pretty at 2:58

@danielfernandocarballo1890

6 жыл бұрын

Pretty and deadly as hell.

Hi Doug. And thank you for the great help you give us all.Could you please comment on the significance/importance of cleaning/removing the Copper Oxide from the Copper Chromite,before proceeding to use it in the Niacin to Pyridine process? Thank you.

Thumbs up for science words!

3:07 this is how you make portal gel.

@thenewbgamer6416

4 жыл бұрын

*hmmmmmm*

tbh you have some cool videos

Anyone noticing that the starting materials are like the blue and orange portals in the game Portal?

To stir twice as fast, use two stirbars

@zanpekosak2383

7 жыл бұрын

Charles Stephano If you want 10 times the speed,use 10 stir bars abd buy 10 beakers.

good

orange and blue were my Cholla high school colors

Copper (II) oxide or basic copper carbonate are nearly as effective as decarboxylation catalysts for niacin but then you wouldn't have the fun of making copper chromite I suppose. Oxidation is not a significant issue in this case.

@chrisfromnz3038

6 жыл бұрын

Did you ever get around to comparing the yields between copper carbonate and copper chromite John Black Super Chemist?

@ThePatos1

5 жыл бұрын

yields are 40/54 with carbonate, 80/90 with chromate

Are the equations at 0:05 right? Maybe it's a class of compounds unknown to me, but shouldn't the copper ammonium chromate be written as Cu(NH4)2(CrO4)2? Cuz you wrote it Cu(NH2)(CrO4)2. Isn't the NH2 group an amide group? Amides have a negative charge. If I'm wrong please explain me. Also I'm quite sure that ammonium chromate is (NH4)2(CrO4), not (NH4)(CrO4).

@AndyU96

5 жыл бұрын

Pietro Tettamanti He is that hated type of person who doesnt reply to comments, it seems

i got 1 question, what is the function of the process where u burn the catalyst inside a crucible ceramic at 400 dgree?

Nice, you had me thinking the wifi was out or something...

I made some. How do you clean the frit of the copper chromite? HCL worked on the precipitate real well but what to use on the copper chromite from the last filter step?

@dpasek1

2 жыл бұрын

Nitric acid should work. Try dilute (10% dilution of concentrate) first. Most nitrates are soluble in water. Otherwise, you might need a complexing agent.

i know this is a older video but i have a question: could potassium dichromate be used instead of sodium dichromate?

@bromisovalum8417

4 жыл бұрын

he used ammonium dichromate, you have to use that

What is the liters size of the vacuum flask that you use for the vacuum filtration?

@ScienceWithJames

6 жыл бұрын

Looks like 1 Liter.

You are noticing that your solution is getting pulled into your vacuum line, a little. That can eventually destroy your pumps internal parts!

@cee3do358

9 ай бұрын

He is using an aspirator. Saves so much $ and frustration.

@b-rad3937

2 ай бұрын

​@@cee3do358yea I don't think this is his first rodeo lol

You mentioned that you used _ammonium dichromate,_ but can this be carried out with _potassium_ dichromate as an alternative?

@thechemicalchameleon9195

2 жыл бұрын

No because the potassium can't be driven off in the decomposition reaction step which would leave all of the potassium in with the product so you can't separate the potassium out very well or easily so you don't end up with copper chromite in the end.

If the sulphuric acid is very clean but just diluted, can you not evaporate all the water off at 200 deg C?

can i use potassium dichromate?

damn that's an old Bunsen Burner, you must have found that at some sort of yard sale or something lol

@AwsomeVids83

7 жыл бұрын

Anthony Kernich He said it was homemade

@AlonsoRules

7 жыл бұрын

that's awesome! Probably cost 1/10 of the price too.

@AwsomeVids83

7 жыл бұрын

***** Yep, it's really easy and cheap to make burners like that. Just buy some steel pipe fittings and screw them together in the right ways and all different kinds of burners can be made. It's quite fun, you should try it!

how can i make cu+tio2 catalyst

-this works- - *this works* *

@mistertheguy3073

7 жыл бұрын

- (Text) - * (Text) *

What’s the original dark green filtrate consist of? Is it toxic to dispose of? Any chromium?

Does anyone know the name of the piece of glassware in vacuum filtration that you put the liquid mixture in?

@12345NOU54321

8 жыл бұрын

Glass fritted filter

@james1458256

8 жыл бұрын

Buchner funnel

At 13:11 was that dust some of the catalyst? If so how come it was doing that? Was the stirring causing a slight 'gust' upwards to evacuate some of the fine powder?

@smitetheunholy6179

8 жыл бұрын

+Samdroxpie Possibly the pouring of the powder will have displaced air in the beaker causing a small updraft

@OeNoesRAWR

8 жыл бұрын

Ah right, makes sense - Thanks

One issue with ammonium dichromate is its toxicity and it is next to impossible to obtain as an individual in EU. Are there any alternative catalists that are better-yielding than basic copper carbonate?

@bromisovalum8417

4 жыл бұрын

"next to impossible" you say? 50 grams of chromium trioxide are dissolved in small amount of water. The obtained solution is treated with 33 ml of the concentrated (d=0.9 g/ml) solution of ammonium hydroxide. Then the solution is concentrated by evaporation and obtained crystals of ammonium dichromate are filtered and dried in a desiccator over concentrated sulfuric acid. The yield of ammonium dichromate is 70%.

@bromisovalum8417

4 жыл бұрын

But yes if you live in Germany or Austria (and a few others iirc) they won't ship chromates to you, many other EU countries are fine as long as you remain under a stated treshold in amount. I suspect CrO3 will fall under the same regulation. But don't be so quick to give up, if dichromates are unavailable for you, make them yourself. The beauty of hobby chemistry. There's always a way around, sure it takes extra work, but as a hobby chemist this should be a welcome challenge. Especially since we're talking inorganic chemistry here.

6:34 use rather coffee filters

Couldn't you 'just' slit the ring so the thermal expansion difference won't crack the crucible?

@dpasek1

2 жыл бұрын

Use a wire triangle crucible support instead.

The quality to views ratio of this video offends me.

@robertheal5137

6 жыл бұрын

the views to likes ratio also not so good

@kieranodea771

5 жыл бұрын

@@memberwhen22 We care because his channel deserves more viewers and likes, which would give Doug an incentive to make more videos.

Use chromic acid and cuco3.cu(oh)2

It seems impossible to get ammonium dichromate or chromium trioxide in EU due to REACH regulation :((

@dpasek1

2 жыл бұрын

You should be able to get trivalent Cr salts instead, and oxidize them yourself. With more work, you can make hexavalent chromium starting with 18-0 stainless steel from cheap flatware like forks and spoons. Dissolve in aqua regia and process from there.

Intermediate maybe is Cu(NH 4)2(CrO4)2 not Cu(NH2)(CrO4)2

Please write quantities of materials accurately

Hey Doug, im 13 years old and currently have my own lab that i use often and have been wanting to make videos documenting my experience. do you have any tips?

@BunsenBurns

8 жыл бұрын

+Ac Hendrickson Obviously not Doug but I started with my own lab and my biggest suggestion is just go for it! Simple things first, of course. Start recording, filming, and be safe!

@Striiiider

8 жыл бұрын

+Bunsen Burns thanks a lot, do you have any reactions that are good for practice?

@BunsenBurns

8 жыл бұрын

If you have a hot plate, I would recommend heating baking soda and observing its decomposition into sodium carbonate. It's pretty interesting and safe as long as you are very cautious of the hotplate. You can also calculate how much mass you start with and the mass you lose.

@Striiiider

8 жыл бұрын

+Bunsen Burns wow thanks for the fast reply, I don't have a hot plate but I do have a wickless heater. Would that work?

@BunsenBurns

8 жыл бұрын

I would recommend heating on the stove then. In that case you don't even need a beaker and in fact I would recommend using a pan. This is just straight kitchen chemistry, after all. You can store the sodium carbonate for later use.

As simple as that

Ammonium chromate looks a lot like urine. Probably smells like it because of the ammonia. Think I can cheat a pee test with it?

Tree Fiddy?

Coppersalts down the sink!? WTF?

@hedgeclipper418

7 жыл бұрын

when did he pour copper salts down the sink? I didn't catch that.

@chrisX1722

7 жыл бұрын

at about 17:57

@adityavarma193

7 жыл бұрын

"discarded down the sink". Copper acetate is toxic to life

@zanpekosak2383

7 жыл бұрын

Cooper salts are "not that bad". Mercury is worse.

@adityavarma193

7 жыл бұрын

Copper salts are actually quite bad for the environment. Mercury salts may be worse but copper salts can cause deformities and other bad effects to wildlife.

Copper 'AMMONIUM' chromate? You just butchered all chemical nomenclature right there