硫代硫酸钠溶液降解溴甲烷熏蒸尾气的评估试验研究

Degradation of methyl bromide by sodium thiosulfate solution in fumigation effluents

硫代硫酸盐是一类能与卤代烃发生快速反应的亲核试剂,已应用于溴甲烷化学降解技术研究和处理设施中。为了促进硫代硫酸钠溶液在溴甲烷熏蒸尾气无害化处理中的应用,本文开展了影响降解率的主要因子的测试评估试验研究,结果表明,硫代硫酸钠溶液能快速降解尾气中的溴甲烷,且溶液浓度、气体流速、反应液的温度和高度等因素显著影响溴甲烷的降解率,但溴甲烷初始浓度对降解率无显著影响。在本试验测试条件下,硫代硫酸钠溶液浓度大于0.2 mol/L、反应体系的温度维持在25℃左右为合适的降解条件。

Thiosulfate is a kind of nucleophilic reagent which can react with halogenated hydrocarbons quickly.Therefore ,it has been used in the research and chemical degradation of methyl bromide.In order to promote the application of sodium thiosulfate solution in harmless treatment of methyl bromide in fumigant exhaust gas,studies on the testing and evaluating the main factors that affecting the degradation rate were carried out.The results showed that the solution of sodium thiosulfate could rapidly degrade methyl bromide in tail gas,and the degradation rate was significantly affected by the factors such as solution concentration of sodium thiosulfate,gas flow rate,temperature and the height of reaction solution, but the initial concentration of methyl bromide had no significant effect on the degradation rate.Under this testing system,maintaining the reaction system temperature at about 25℃ with the sodium thiosulfate solution above 0.2 mol/L were the optimum operating conditions.