15 replies to this topic

[digger]

Has anyone used these chemicals in any compositions? what results did you get?

I notice from the science forums that YT2095 has had a dabble with them. How did that turn out?

[YT2095]

rather nicely actually, and simple enough to make (ammonium benzoate and the metal chloride).
it`s a Little Lossy though as the product is a little soluble.

Benzoic acid and the metal Carbonate or hydroxide will work also, BUT again, this is also lossy and can lead to impurities of undissolved reagents and it requires heating.

as for an end product they work quite nicely as a color donor

[MDH]

You couldn't make chlorate whistles out of them? (Yes, I say chlorate because it would burn at a lower tempature and produce better color).

Or, colored report compositions. Think of the possibilities... Red whistle to green report. Haha.

I know that copper and sodium benzoate make very, very good colour donors.

Edited by MDH, 04 April 2008 - 05:18 PM.

[YT2095]

no, the problem I Had was with NOT using any Metal ion, I tried the benzoic free acid and also the Ammonium benzoate, they didn`t work at all, the Metal ion benzoates all work.
as for whistles, I never tried, I`m not legaly entitled to make such a construction.

[digger]

rather nicely actually, and simple enough to make (ammonium benzoate and the metal chloride).
it`s a Little Lossy though as the product is a little soluble.

Benzoic acid and the metal Carbonate or hydroxide will work also, BUT again, this is also lossy and can lead to impurities of undissolved reagents and it requires heating.

as for an end product they work quite nicely as a color donor

Thanks for the reply very interesting, I made up some copper benzoate today using benzoic acid.

I did the reaction at 70C on a hotplate stirrer first to potassium benzoate (adding potassium carbonate until ph8), then made up some copper sulphate from H2S04 and copper carbonate (just past ph7). Then precipitated out the copper benzoate. Then vacuum filtered and washed. It is now drying out.

Do you have any solubility data for the barium and the strontium benzoate?

I may try benzoic acid / carbonate route with a slight excess of carbonate.

I have come to the end of my benzoic acid supply, do you think it would be possible to produce reasonably pure benzoic acid from sodium benzoate and nitric acid (don't fancy messing around refluxing benzyl alcohol with potassium permanganate)?

[pyrotrev]

I have come to the end of my benzoic acid supply, do you think it would be possible to produce reasonably pure benzoic acid from sodium benzoate and nitric acid (don't fancy messing around refluxing benzyl alcohol with potassium permanganate)?

Mmmm, there might be easier ways. Firstly you could precipitate out the different benzoates by mixing a NaBenz solution with a solution containing the Ba/Sr ions. You might need to wash it a bit to get rid of any residual Na, but since Ba and Sr have pretty strong emission spectra (with a chlorine donor), it won't likely be too much of a problem. Alternatively you could convert the NaBenz to ammonium benzoate by adding ammonia or ammonium nitrate, and evaporate/cool to crystallize out the NH4Benz - it's actually appreciably less soluble than NaBenz at 20deg C. You can then make your different benzoates from this as YT2095 detailed before.

[seymour]

In my experience Copper benzoate burns too hot for my liking. I go for colour depth over brightness, especially with blue where it tends to be one or the other. However, I find Cu benze to be ideal in purple. A good example of that is Blesser AP purple:

Ammonium Perchlorate 68
Strontium Carbonate 12
Copper Benzoate 8
Hexamine 7
Magnalium, granular, -325 mesh 5
Dextrin 4


A strontium benzoate composition that I made burns a very deep red, but seems to be more hygroscopic than a normal Strontium nitrate mix (yes, I used Strontium nitrate too, not a very good way to test how good the benzoate is, I know).

Barium benzoate I have not yet made.

[digger]

Mmmm, there might be easier ways. Firstly you could precipitate out the different benzoates by mixing a NaBenz solution with a solution containing the Ba/Sr ions. You might need to wash it a bit to get rid of any residual Na, but since Ba and Sr have pretty strong emission spectra (with a chlorine donor), it won't likely be too much of a problem. Alternatively you could convert the NaBenz to ammonium benzoate by adding ammonia or ammonium nitrate, and evaporate/cool to crystallize out the NH4Benz - it's actually appreciably less soluble than NaBenz at 20deg C. You can then make your different benzoates from this as YT2095 detailed before.

Fair enough I may give that a go, my main concern was sodium contamination, hence benzoic acid route as it is a doddle to purify due to its solubility curve.

Seymore

Interesting I may give that purple a go. According to the skylighter newsletter the following is a very good blue which I was intending to give a go.

Ammonium perchlorate 82
Copper benzoate 18
Dextrin +5

[Mumbles]

Just a bit of clarification. Yes, all the benzoates work to produce whistle type effects. The problem is that most of them don't produce whistles within the audible range of humans from what I have heard. The dogs may start to hate you though.

[digger]

Just a bit of clarification. Yes, all the benzoates work to produce whistle type effects. The problem is that most of them don't produce whistles within the audible range of humans from what I have heard. The dogs may start to hate you though.

So I hear or not as the case may be.

I would like to try some of these compounds for colour production, purely from an experimental point of view (it gives me some chemistry to play with over the long summer nights if we get one). I am sure that I have heard it said that they can also be used in colour report compositions, how true that is I do not know.

[digger]

no, the problem I Had was with NOT using any Metal ion, I tried the benzoic free acid and also the Ammonium benzoate, they didn`t work at all, the Metal ion benzoates all work.
as for whistles, I never tried, I`m not legaly entitled to make such a construction.

YT2095, I have been doing a bit more reading and have come round to your way of thinking, using metal nitrates with ammonium benzoate.

My question is did you make your ammonium benzoate with benzoic acid and ammonium carbonate and then boil to remove any ammonium carbonate? If not what is a better route to this precursor?

[YT2095]

nope, I bought my ammonium benzoate as it is.
it shouldn`t be Too hard to get though, it`s used in quite a few shampoos and other cosmetic thingies, so it`s not classed as a dangerous chem

if I were to Make it, I would start with K Benz and acidfy this to ppt out the benzoic acid, wash this several times with deionised water and then dissolve it in ammonium hydroxide.
evaporate to dryness.

Edited by YT2095, 10 April 2008 - 05:47 PM.

[pyrotrev]

I'd be tempted to make it simply from ammonia solution (local hardware store - cheap as p**s) and benzoic acid, since from my suppliers the latter is cheaper than any benzoates.

[digger]

I'd be tempted to make it simply from ammonia solution (local hardware store - cheap as p**s) and benzoic acid, since from my suppliers the latter is cheaper than any benzoates.

Interesting.

The cheapest thing I can get at the moment is the sodium benzoate at £3.30 / Kg (maybe even cheaper through work) and HCL at £1/l for 30% stuff. So that would work out at about £5/kg to make benzoic acid. Can you get it close to or cheaper than that?

If so would you mind PM'ing me your supplier?

[pyrotrev]

Interesting.

The cheapest thing I can get at the moment is the sodium benzoate at £3.30 / Kg (maybe even cheaper through work) and HCL at £1/l for 30% stuff. So that would work out at about £5/kg to make benzoic acid. Can you get it close to or cheaper than that?

If so would you mind PM'ing me your supplier?

That depends a bit on quantities I guess! - certainly at the small 500g quantities I priced up, I couldn't find the ingredients that cheap. I was originally comparing benzoic acid with potassium benzoate (which seems to be considerably more expensive than sodium) following YT2095's post and desperately seeking to avoid sodium contamination.