纸上光度法间接测定痕量硫离子  

INDIRECT DETERMINATION OF TRACE AMOUNTS OF SULFIDE BY PAPER-ADSORPTION-PHOTOMETRY

作　　者：啜惠民[1] 赵惠芝[1] 

机构地区：[1]河北科技师范学院化学系,昌黎066600

出　　处：《理化检验（化学分册）》2004年第7期386-387,共2页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：用过量的铜标准溶液与含S2-样品溶液作用,加入适量的二氯甲烷,使生成的硫化铜微晶滞留在有机相中,用纸上光度法测定残留在水相中的痕量Cu2+,间接测得样品中S2-的含量。测定的pH范围为3～6,S2-的测定范围为3×10-6～9×10-6mol·L-1,RSD小于3%。An excess amount of standard Cu^(2+)-solution (1×10^(-5)mol·L^(-1)) was added to the S^(2-)-containing water-sample solution and an appropriate amount of dichloromethane was added to retain the micro-crystalline CuS in the organic solvent. The cupric ion in the water phase was made to react with the xanthate paper forming a yellow spot, the absorbance of which was determined at 400nm. The decrease in absorbance (ΔA) of the cupric xanthate spot was found to keep a linear relationship with the concentration of sulfide ion in the water sample in the range of 3×10^(-6)～9×10^(-6)mol·L^(-1). The optimum acidity of the reaction medium was found in the range of pH 3～6. The RSD′s (n=5) obtained in the indirect determination of sulfide ion in river water samples were less than 3%, and the average recovery found was 98.5%.

关 键 词：纸上光度法 黄原酸酯滤纸 铜离子 硫离子 水样 

分 类 号：O657.31[理学—分析化学]