Sciencemadness Discussion Board

ammonium bicarbonate manufacture

thrival - 21-11-2014 at 11:59

I've been looking around to price Ammonium Bicarbonate and the best I can do is $6.00/lb. in bulk. Then it occurred to me I might be able to make my own. I found a source of dry ice delivered at $1.00/lb and I can buy commercial ammonia for about $2.00/gal. So my question is how to determine my output, i.e. how much ammonia is trapped in a gallon of solution and how much dry ice do I need to combine with it. Of course I'm hoping to obtain best conversion possible with least waste of material & money. thanks in advance!

gdflp - 21-11-2014 at 12:12

Well, firstly you will need to find the concentration of ammonia you are going to buy, there are many different concentrations at different price points. Secondly ammonium bicarbonate is rather unstable, it decomposes at 36°C so making it may not be as easy as you first thought. Also what's your definition of bulk, here is an ebay listing for 50lbs at $4/lb with free shipping. http://www.ebay.com/itm/Ammonium-bicarbonate-repackaged-food... When you consider packaging costs and your time, the profit margin may drop very quickly. Also, care to share your source of dry ice, a lot of members might benefit from having a source that cheap?

[Edited on 11-21-2014 by gdflp]

thrival - 21-11-2014 at 15:25

gdflp: Well you're right, $4.00/lb is a good price but $200. for 50lbs. is a bit over-budget for me. The dry ice supplier is local (Milwaukee/S.E. WI) and their minimum is $10lb. although for the price is really a waste of time for them and more of a favor and piggy-backed with other deliveries; they'd like to sell you a lot more.

As for exact ammonia concentration, who knows?! It's "restaurant grade."

[Edited on 21-11-2014 by thrival]

Artemus Gordon - 21-11-2014 at 15:42

Quote: Originally posted by thrival  
gdflp: Well you're right, $4.00/lb is a good price but $200. for 50lbs. is a bit over-budget for me. The dry ice supplier is local (Milwaukee/S.E. WI) and their minimum is $10lb. although for the price is really a waste of time for them and more of a favor and piggy-backed with other deliveries; they'd like to sell you a lot more.

As for exact ammonia concentration, who knows?! It's "restaurant grade."

[Edited on 21-11-2014 by thrival]


What on Earth do you need 50 lbs of (NH4)HCO3 for? Unless you are planning on mass-producing Chinese steamed buns or chrome-tanned leather, I can't imagine a use for 50 lbs of the stuff.

gdflp - 21-11-2014 at 17:57

I'm still not quite sure what your goal is. Are you trying to make money by selling it, or do you have a specific use for it? As for the ammonia, if it doesn't have a concentration on it, then you'll need to titrate it. I would recommend 6M HCl and methyl orange as an indicator.

[Edited on 11-22-2014 by gdflp]

thrival - 21-11-2014 at 19:22

Artemus Gordon: I never claimed to need 50 lbs. and I said even @ $4./lb, is over-budget.

gdflp: The goal is to save money making it myself. I'm not familiar with titration prctice, was hoping there might be a standard concentration sold in commerce that someone would know, at least as a ballpark to guestimate how many bottles of ammonia I might need to sequester 10 lbs. of frozen CO2.

j_sum1 - 21-11-2014 at 19:50

Ok. I'm going to do the math on local currency and otc products. Yours will be slightly different but I think you will find that the $4 per pound is going to be hard to beat.

1 pound of dry ice is $1 by your source. This is almost exactly 10 moles of CO2.

Locally, I can buy 5% ammonia solution from the supermarket as a floor cleaner. A 1 litre bottle costs a little over a dollar (AUS). Let's call it a dollar US. 5% by weight works out to about 3 moles per litre and so I will need 3 1/3 bottles per pound of dry ice.

Assuming 100% yield, a pound of dry ice will give 1 pound 14 oz of ammonium hydrogen carbonate product. Raw materials by the above estimate come to $4.33. So, this works out at $2.30 per pound in reagents.

Now, your ammonia solution might be stronger and/or cheaper. (Or not.) I have no idea what kind of yield you are expecting. Gdflp suggested that it is rather unstable and you might not get the yield you hope. Then you factor in the time and effort to make the stuff which I would suggest is a couple of hours as a minimum. $6 per pound is starting to look quite good.


Edited. i just checked. My ammonia is 2% by weight and not 5%. That would make it $9.33 in reagents for 1lb 14oz, or $4.95 per pound of product.

On the basis of this I would have to say that you will save yourself some time, hassle and probably money if you can find it for $6 per pound. That is unless your access to ammonia is a whole lot better than mine.

[Edited on 22-11-2014 by j_sum1]

thrival - 21-11-2014 at 20:54

j_sum1: thanks for crunching those numbers for me.

I just found the customer service # on the product label so will call tomorrow to hopefully learn what concentration. 1 gal bottles for $2.00 each.

gdflp - 21-11-2014 at 22:39

This is just a complete guess, but restaurant ammonia might be a maximum of 10% ammonia. I would guess that it is a lower concentration actually just because it is so cheap. In addition, what is the intended purpose, chemistry or baking? I would not trust either starting material to produce a food grade product.

thrival - 14-12-2014 at 00:01

OK, I decided against the above method for now. Wondering if adding CaMgCO2 to Ammonia and distilling it would produce an ammonium carbonate solution. Does anyone know if this will work? ...or would I do better distilling ammonia over charcoal? I'm trying to get away from the need of calcining or burning either. Thank you.

[Edited on 15-12-2014 by thrival]

thrival - 15-12-2014 at 01:08

Found my answer-- (Yes!)

gdflp - 15-12-2014 at 09:18

I'm guessing you mean CaCO3 and MgCO3. If so, you won't be able to distill it, ammonium carbonate is rather unstable and on even slight heating will decompose according to the following equation, (NH4)2CO3 --> 2NH3 + CO2 + H2O

S.C. Wack - 15-12-2014 at 16:23

Well, there's Google, and books 100-150 years old.
A recommended search term is ammonium sesquicarbonate. It is produced by heating, and sublimation can go on for weeks.

thrival - 16-12-2014 at 02:01

As a matter of fact I did find my answer in The Cyclopaedia; or, Universal dictionary of arts, sciences, and literature (1819) by A.Rees.

I learned that ordinary steam run through coal/charcoal extracts carbonic acid. That tells me a boiling process of ammonia/charcoal through distillation apparatus will probably produce an ammonium carbonate solution. Sad that a person must find answers from old books that modern chemists don't know.

forgottenpassword - 16-12-2014 at 02:08

Why is it sad? It would be more sad if people didn't read the books that others have taken the time and effort to write. It doesn't matter when it was written: chemistry is timeless. Modern chemists have attained a level of sophistication far greater than leading steam through a bed of charcoal. There has been no sad decline in chemistry, only a triumphal advance. The body of knowledge accumulated over the past 200 years is astonishing. Don't feel sad because you have to look it up in an old book. If it worked then it'll work now. If it's good enough for your purpose then use it.

[Edited on 16-12-2014 by forgottenpassword]

thrival - 16-12-2014 at 06:51

fp: Only meant that modern chemists seem not to know so many basic things with all their advancements. I don't mind reading old books, often they were much clearer and universally understandable, vs. today's which often focus on mathematical aspects over principles.

DieForelle - 17-12-2014 at 01:23

Wow. What a bizarre thread. Though, related to something I've been thinking about. I've wondered how they make those crispy light confection wafers especially common in Europe. (Loaker's Quadratini etc.) Years ago I ordered some Ammonium carbonate from Science Company in Denver. Never got around to using it. Recently I've gone a bit low carb and wanted to figure out a way to make something similar that was gluten and sugar free. (crispy wafer with sugary filling) GF foods seem very expensive. So I started investigating the stuff again and noticed something I'd not before.

All of the European and Asian sweets manufacturer list Ammonium bicarbonate as the ingredient. But if you search the web for people selling "hartshorn salt" to home bakers, it's all Ammonium carbonate. It actually surprised me that there was a distinction, industrially, but there is. And they have decidedly different decomposition points. So, I suspect the commercial bakers use the bicarbonate because they can order from a supplier in a way that keeps it stable. In theory it would puff a bit better. After all, we use sodium bicarbonate as a leavening, not sodium carbonate! The US retailers sell Ammonia carbonate because I guess riding around in hot UPS truck won't cause it to all evaporate as it would the bicarbonate.