Established Methods for the Neutralization of Ammonia

Factual Questions
1

I am a co-op student at a coal plant, and a supervisor of mine has requested my opinion on the best method to neutralize some excess aqueous ammonia. I have no experience with ammonia, so I am unsure how to proceed. Sulfuric acid in the form of 66 Baume (93% Acid by weight) would appear to be an economic choice for a neutralizing agent, as we have some left over from a previous project. Acetic Acid has also been proposed as a potential neutralizing agent. Unfortunately, at this time I do not know of the amount of ammonia that is to be neutralized, nor do I know its level of purity.

If there are standard methods for neutralizing aqueous ammonia I’d certainly appreciate the info. Ideally I’d like to know what proportions / conditions are appropriate to facilitate complete reaction between the proposed acid and the excess ammonia.

Any information / recommendations / sources would be greatly appreciated.

~ Mattprole

2

Check aquarium suppies. There are ammonia and chloramine neutralizing agents. I don’t have any more details.

3

If by neutralize, you mean get it to a pH near 7, I would not recommend sulfuric acid unless you have a lot of time to get the pH just right. Sulfuric acid is a strong acid, and going from basic to acidic will be a very sharp point. If you know the approximate concentration of ammonia, you can get close with sulfuric acid, then adjust with acetic acid.

You will need to monitor the change in pH with a meter, an indicator or pH paper. I would titrate a small amount first to get an approximate amount of acid. You will want to give the solution some time to respond if there are impurities like coal in it.