Identification of chlorinated compounds in the spent chlorination liquor from differently treated sulphite pulps with special emphasis on mutagenic compounds.

About 80 compounds present in the spent chlorination liquor from the bleaching of sulphite pulp have been identified. A comparison has been made between these compounds and those identified in kraft bleaching effluent, with special emphasis on mutagens. The influence of oxygen delignification, before chlorination and alkali treatment of the spent bleach liquor, on the composition of the liquors has also been investigated.