We solve the problem of disposing used etchant simply.

I called my local utility, and they were comfortable with minute quantities
in ther waste stream.  So we can wash out etch tank, once it has drained, in
plain water.  They asked us to flush it heavily with plenty of water.  This
is no more than a teaspoon of used etchant at a go.

The rest, we keep in a big jug.  We've stiull got every drop of etchant
we've ever used.  I talked to our hazardous waste coordinator, and he said
"Just keep it."  So 3 gallon jugs of used etchant sit in the back of my haz
chemical cabinet.

-- Lawrence Lile

P.S.  Just don't mix it with any Dihydrous Monoxide, or Hydroxic Acid as it
is also known!

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body