摘要
催化裂化冷凝脱水是一个相当复杂的成份,对分析干扰非常严重,一些炼厂对硫化物的分析常采用亚甲基兰法,因为该法只适用测定低浓度硫化物,对冷凝脱水中高浓度硫化物测定结果误差很大。作者用碘量法测定硫化物,大大提高了分析的准确度,结果表明ZnS在pH=10的NH_4Cl-NH_3-H_2O缓冲液中沉淀,是准确分析硫化物的关键。
The medium in catalytic dehydration is quite complicated so that it interferes with analysis to a great extent, Sulphide in catalytic dehydration of refineries has been petermined by methylene blue method, which is only suitable for lower concentration of sulphide. For higher sulphide concentration, the amount of sulphide can be accurately measured by using iodiometry. It is shown that the optimum condition to determine sulphide is to precipitate ZnS in the buffer solution of NH_4Cl-NH_3·H_2O at pH 10.
关键词
硫化物
凝结水
催化裂化
碘量法
sulphide, catalytic cracking, condensate, iodometry.
