WHITE LIQUOR OXIDATION IN A PILOT-PLANT PIPELINE REACTOR

An in-line pilot reactor studied the effects of operating variables on sulfide conversion and oxygen utilization efficiency. The study exami ned conversion with varying oxygen to sulfide molar ratios. Clarified white liquor without black liquor catalyst oxidized as effectively und er pressure as white liquor containing line mud. Increasing the oxygen to sulfide molar ratio gave declining oxygen utilization efficiencies due to poor gas and liquid mixing. Thiosulfate was the primary oxidat ion product under all experimental conditions using no foreign catalys t. Much longer retention times would be necessary to convert the sulfi de to sulfate.