恒压内循环分离-吸收法测定水体中硫化物

Study on determination of sulfide contents in water by constant-pressure recirculation separation-absorption method

采用自行设计、制作的恒压内循环分离一吸收实验装置测定水体硫化物含量，并讨论了内循环气体流量、反应时间等因素对测定结果的影响。实验结果显示，当内循环气体流量高于700mL／min时，硫的回收率可达95％以上，当反应时间延至20min，甚至达到60min时，硫回收率都达到了95％以上。内循环吹气吸收法在室温条件下就能满足实验要求，反应液硫含量在5～40 μg之间时，硫的回收率可达95％～105％，检出限为5 μg／L。研究还就方法的准确度进行了误差计算，并对宁波市实际水体进行了硫化物含量测定。

The device of constant-pressure recirculation separation-absorption was firstly conducted to determine sulfide contents in water and to investigate the influence of various operation factors （ gas flow rate, separation time, temperature, etc.） on the sulfide contents in water. The results showed that the sulfide recovery achieved above 95% when the gas flow rate was higher than 700 mL/min. The recovery above 95% was also attained when the reaction time was extended to 20 min, even 60 min. Especially, the method could be operated under room temperature. The sulfide recoveries were 95% ～ 105% when the sulfide contents in the reactor were 5 - 40 μg. The detection limit in the method was 5 μg/L （ S^2-）. The accuracy of this method was presented by measuring error. Thus, the sulfide contents of inner-river in Ningbo city were determined.