Can plaster of paris be recycled?

Question

Can plaster of paris be recycled?

Answer 1

You can maybe give it away.  There is a website where lots of people are looking for free stuff.  The site is http://www.freecycle.org/

Answer 2

If you are talking about a c***k of solid Plaster of Paris, my kids love to use it as a sculpting medium, then take the scrapings after they're done with their project, and add water to the powder to make chalk and other craft projects.

If you shave or grind a chunk down, it can be reused indefinitely by adding water again to form a new paste.

If you just have the powder, don't want it, and need to find it a new home, you can list it on the ReUseIt network, the Freecycle Network, Craigslist, or any of the myriad of other sites and services geared towards reducing waste in our communities. You could even donate it to a school or church group, who I'm sure would be able to find a crafty use for it.

Answer 3

No way! I was wondering the exact same thing today! I had all these leftover moulds I wasn't going to use. I just read "hannah's grandpas" reply, it was perfect! I can't believe I can just recycle it myself. And save money instead of buying new plaster.

Answer 4

yes it can.

Plaster of Paris (gypsum hemihydrate) is in fact created

industrially by heating fully hydrated gypsum (the

dihydrate). Typically the dihydrate must be heated moderately

above the boiling point of water; usually about 120°C to 170°

for a specific time to drive off excess water of

crystallization and result in the hemihydrate. Since Plaster

of Paris that has "set" is the same thing a gypsum, the

results will be the same, whether heating gypsum, or "set"

Plaster of Paris.... the hemihydrate will result.

So in answer to your question, Plaster of Paris can be

"recycled" endlessly by the above method. As to how finely it

needs to be reground, I suspect that the hemihydrate has

essentially no structural strength, and thus will crumble

easily to

powder, so significant effort to regrind it is

probably not needed.