基于新方法探讨如何准确测定石化废水中的硫化物

Accurate Detection of Sulfide in Petrochemical Waste Water Based on a New Method

对比《水质硫化物的测定气相分子吸收光谱法》HJ/T 200—2005和HJ 200—2023的不同之处,进行方法比对考察试验及方法验证。结果表明:采用乙酸锌固定样品可保存7 d;NO2-对测定产生负干扰,且不能通过加入过氧化氢消除;对于石化废水样品,可采用乙酸锌固定后加入抗氧化剂和过氧化氢再经“酸化-蒸馏-吸收”的方法去除干扰;磷酸或盐酸作酸化剂的效果相差不大。标准曲线在0~5.00 mg·L^(-1)内具有良好的线性关系,方法检出限为0.005 mg·L^(-1);精密度、准确度和加标回收率验证均满足HJ 200—2023的要求。

The differences between HJ/T 200—2005 and HJ 200—2023 were compared,and the methods were compared and verified.The results showed that the samples fixed with ZnAC could be preserved for 7 d.NO2-produced negative interference to the determination and could not be eliminated by adding H2O2;for petrochemical wastewater samples,the interference could be removed by the method of"acidification,distillation and absorption"after fixing with ZnAC,adding antioxidants and H2O2.The effect of phosphoric acid or hydrochloric acid as acidifiers was not different.It was proved that the standard curve had a good linear relationship in the range of 0~5.00 mg·L^(-1),and the detection limit of the method was 0.005 mg·L^(-1).The precision,accuracy and recovery rate of standard addition all met the requirements of HJ 200—2023.