Solid hypochlorites

The most stable solid hypochlorites are those of Li, Ca, Sr and Ba (see below). NaOCl has only poor stability and cannot be isolated pure KOCl is known only in solution, Mg yields a basic hypochlorite and impure Ag and Zn hypochlorites have been reported. Hydrated salts are also known. Solid, yellow, hydrated hypobromites Na0Br.xH20 (x = 5, 7) and K0Br.3H20 can be crystallized from solutions obtained by adding Br2 to cold cone solutions of MOH but the compounds decompose above 0°C. No solid metal hypoiodites have yet been isolated. 

Impact damage occurred to one of 48 10 kg polypropylene tubs of calcium hypochlorite, each closed with a polythene lid, all supported on a wooden pallet and stretch-wrapped round the base with polyethylene film. The spilled material was swept up and discarded, and the pallet was moved to another part of the warehouse, and some 30 mins, later flames were seen at the base of the pallet [1]. Ignition was attributed to contact between residual solid hypochlorite on the pallet and lubricant drips on the concrete floor from fork lift traffic. Application of a dry powder extinguisher had little effect on the fire, but use of a 40 1 water extinguisher led to rapid escalation of the fire as contact between hypochlorite... 

Solid hypochlorites [e.g., high test hypochlorite (HTH), super tropical bleach (STB), and Dutch powder] are also effective in destroying G-series agents. Reaction with hypochlorites, including household bleach, may produce toxic gases such as chlorine. 

Skin contact with the solid hypochlorite pentahydrate or its concentrated solution can cause irritation. Ingestion may cause corrosion of mucous membranes and gastric perforation. 

The hypohalite ions, OCl, OBr, and OI, are formed (along with equivalent quantities of the corresponding halide ions) when the elemental halogens are hydrolyzed in basic solution. Two solid hypobromites and several solid hypochlorites have been isolated. The so-called bleaching powder or chloride of lime, prepared by treatment of calcium hydroxide with chlorine, is often described as a mixed salt Ca(OCl)Cl (however,... 

Solid hypochlorites are stable up to 80 °C, their stability depending on the water content, which is < 1 % for bleaching powder, < 0.3 % for tropical bleach. They decompose by reaction with water or by heating to 180 °C. 

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