Process for the preparation of dissolution l? Quida thiosulfate calcium from lime, sulfur and sulfur dioxide.

a batch method or effective semicontinuous production of calcium thiosulfate (CaS {sub, 2} O {sub, 3}) containing low byproduct content, high relative concentration, from lime, sulfur or polysulfide is described calcium, and sulfur dioxide under conditions of elevated reaction temperature. The product is an emulsion of liquid calcium thiosulfate and solid byproducts. Under the conditions of the art, including the mole ratios of lime with respect to sulfur, the temperature of reaction procedure and reaction conditions of sulfur dioxide, including the rate and duration, the byproducts are reduced to about 2% in weigh.