Calcium hydroxide

Calcium hydroxide, commonly called slaked lime or caustic lime, is a compound used in cement and to treat sewage. It is slightly soluble in water, and saturated solutions are called limewater. I am interested in using calcium hydroxide as a catalyst for the production of diacetone alcohol.

 Calcium hydroxide can be easily made from sodium hydroxide and calcium chloride. I tried this out.

To a 500ml beaker I added 27g of calcium chloride, then just enough hot water to dissolve it. I set the beaker aside. Then to a 250ml flask I added 20g of sodium hydroxide and a sufficient amount of water to dissolve it. Once the calcium chloride and sodium hydroxide had dissolved into solutions, I added them together. A dense white precipitate of calcium hydroxide formed. I filtered the calcium hydroxide off and dried it in the sun. This yielded 22g of calcium hydroxide in the form of a white powder. The photo was taken before the calcium hydroxide was fully dry.

CaCl2 + 2 NaOH ==> Ca(OH)2 + 2 NaCl