酞菁钴磺酸盐脱硫液中硫氢根离子的测定方法

Analysis method of hydrogen sulfide ion in phthalocyanine cobalt sulfonate desulfurization solution

比较了酞菁钴磺酸盐(PDS)湿法脱硫工艺中,测定脱硫液中硫氢根离子浓度的几种分析方法。采用加标分析的方法考察了取样量、沉淀剂种类、沉淀时间、沉淀物分离方法和盐酸用量对分析结果的影响,对碘量分析法进行了优化。优化后的分析条件为:脱硫液采样后立即处理,以防止因氧化导致硫氢根离子浓度降低;以乙酸镉为沉淀剂,沉淀时间10 min,盐酸用量3 m L,取样量10 m L,采用过滤的分离方法,通过电位滴定测定硫氢根离子的质量浓度。在优化条件下,加标回收率可以达到98%。该方法具有很高的实用性,可以应用于PDS湿法脱硫生产装置中,为装置的工艺分析和优化提供依据。

Some analysis methods for detecting the concentration of hydrogen sulfide ion in desulfurization solution in phthalocya- nine cobalt sulfonate （PDS） wet desulfurization process are compared. The effects of the sampling amount, the selection of precipitation agent, the settling time, the separation method and hydrochloric acid amount on the analysis result are investigated by recovery analysis of adding standard sample, and the existing iodimetry is improved. The optimum analysis conditions are obtained as follows： the desulfurization solution should be treated immediately after sampling in order to avoid the decrease of hydrogen sulfide ion content due to oxidation, choosing cadmium acetate as precipitation agent, the settling time is 10 rain, hydrochloric acid amount is 3 mL, the sample volume is 10 mL, the solution is separated by filtration, and the mass concentration of hydrogen sulfide ion is detected by potentionmetric titration. Under the optimum conditions, the recovery of standard sample is 98%. The results show that the mentioned method has great practicability, which can applied in PDS wet desulfurization process to provide the basis for analysis and optimization of the process.