Electronic Circuits and Projects Forum

I thought this would be very easy to find on the internet but got disappointed.

I have already bought 500g 'anhydrous ferric chloride powder'. Do i just add it to water or what ?

secondly, when I am done with the solution, how should I dispose it off ?

Thanks in advance

You can buy the etchant in liquid form or as anhydrous Ferric Chloride powder. Follow the instructions. NEVER add water to dry Ferric Chloride. Don't get any on your clothes.

http://homepage.eircom.net/~ei9gq/pcb.html

Thanks for replying Bill.

I had seen that page but it doesnt have the instructions I need. I already have anhydrous ferric chloride powder. I want to know how make a solution out of it. I think I just need to add it to water but no idea in how much water.

also how do i dispose the solution later.

Hmm I'll use bigger letters.
NEVER add water to dry Ferric Chloride

Read again Bill, I said .... "Add it to water" not "Add water to it". Or do you mean not to do mix water to it in any way ?

It's supposed to have instructions printed on it. If not contact whoever you bought it from for the instructions. Your right you add it to water, I never use the stuff as it's just a mess. Contact your cities hazardous materials department and ask them what to do with the waste.

Originally Posted by pkshima

Read again Bill, I said .... "Add it to water" not "Add water to it". Or do you mean not to do mix water to it in any way ?

You try to mix only that much as you need . don't ever make solution of entire 500gr into solution..

to my experience, you hardly need one to two teaspoons(NEVER STEEL ONES-- ONLY USE PLASTIC)of ferric chloride for 250mlod water,is sufficient to etch two boards of 4*3 " size. you can always use plastic jugs if the dept is sufficient or gp for shallow plastic trays.

when you are done with it-- you need not be in hurry to dispose, unless you don't have any more boards in the near future. As such it can be transferred into a plastic container and closed off with an additional plastic sheet between the cap and the bottle.
Also the entire thing can be sealed in a plastic cover and stored --especially AWAY FROM CHILDREN AND SERVANT MAIDS- AS THEY WOULD NOT KNOW THE CONTENT AND ITS SERIOUSNESS.

You can dispose of used ferric chloride by mixing it with sodium carbonate (or bicarbonate) and you will get a sludge of copper carbonate powder and a solution of sodium chloride (salt). You can pour the solution down the drain and throw the sludge in the garbage.

Personally, since finding Ammonium Persulphate I would never use Ferric Chloride again. AP is so much cleaner.

Mike.
Edit just found this.