Pyrocat 'B' Bath (Potassium Carbonate)

Hi

I know potassium carbonate is a bugger to dissolve, but I assumed that I had done a good job of it when I mixed my last batch a week ago. I was just about to develop some film and I noticed some powder sitting at the bottom of the glass jar. I am aware that the solution does go a bit cloudy, but have never seen this before. The solution was clear apart from this powder resting on the bottom.

Can this stuff go off?

Is it safe to use if I warm it up. I have done so but the solution still looks cloudy.

Your help and advice will be much appreciated

Regards

Stoo

Should be fine Stoo, you could filter the solution through a coffee filter. It's possibly from the water after all where you live it's passed though at least at least 5 people & a few sheep

Ian

A 75% solution of potassium carbonate should be good for a very long time, well over a year. If you get some sediment at the bottom you could filter the solution, as Ian suggests, or you might just shake it immediately befoere you mix it with water to make the working solution. My solutions stay pefectly clear if mixed with distilled water but from time to time I have seen the sediment at the bottom when mixing with tap water.

Sandy King

Thanks Guys.

I mixed the solution using R.O water as I do all my chemicals. I think filtering sounds like the best bet, as long as it is safe to use.

Much appreciated

Regards

Stoo

If you used tap water to make the carbonate solution, and you live in a hard water area, the sediment will most probably be a mixture of calcium and magnesium carbonates. Probably best to decant the clear solution, or filter as Ian says.

(Hah! Too late - That will teach me to type quicker! )

Hi, I just thought I would put the lid on this one.

I did not filter the solution as Ian had suggested. I heated the solution in a cup of hot water that I changed continuously. Then, just before use I gave the solution a good shake as Sandy had suggested, and used it as normal. The resulting negs came out fine and print just as I would expect them too.

Thank you all again

Best

Stoo