Sciencemadness Discussion Board

Ca(ClO)2 synthesis

Ballermatz - 2-12-2007 at 15:35

I havent found any synthesis on the forums - probably because Ca(ClO)2 is easily available off the shelf. Well not to me, so I need to make some. Starting materials I have at hand are TCCS+HCl for chlorine generation and 500g of Ca(OH)2.

In a chemistry book it says that I have to pass chlorine into the Ca(OH)2 solution, then cool it down until the hypochlorite crystallizes, but it doesnt give any details. Which temperature must the Ca(OH)2 solution have? How do I dry the Ca(OH)2 (which probably comes out in a hydrated form) without decomposing it?

chloric1 - 2-12-2007 at 18:25

Ca(OH)2 is only slightly soluble in water so it must be constantly agitated while chorinated. Chlorinate until it is saturated with chlorine. When you are done chill in the freezer but do not freeeze. Your hypochlorite should deposit.

chemkid - 2-12-2007 at 19:10

Anyone have any idea on the normal purity of store bought hypochlorite in the form of bleach? How about other methods of synthesis? Never boguht any bleach becuase i'm concerned about fillers/binders/dyes/crap.

Chemkid

BromicAcid - 2-12-2007 at 19:11

I recall something about reacting chlorine with trays of lime as one of the older preparations. Pretty sure I can find some more details if that isn't sufficient to jog someone's memory around here.

not_important - 2-12-2007 at 19:39

Quote:
Originally posted by chemkid
Anyone have any idea on the normal purity of store bought hypochlorite in the form of bleach? How about other methods of synthesis? Never boguht any bleach becuase i'm concerned about fillers/binders/dyes/crap.


Depends. Plain bleach is generally a solution of NaOCl, NaCl, and NaOH. Water is the filler, cheapest one around. Scented ones generally announce themselves on the label, avoid them and the thickened types sometimes showing up as "no spill"

Yes, bleaching powder was made using trays of the hydroxide or oxide, the hydroxide perhaps being dampened, otherwise with some steam included with the chlorine. There's a lot of 19th century books on practical or industrial chemistry that describe this. This is a little more recent on
http://books.google.com/books?id=MQA5AAAAIAAJ&pg=PA202&a...