快速消解分光光度法测定污水化学需氧量  

Determination of chemical oxygen demand in sewage by fast digestion–spectrophotometry

作　　者：李雪梅 朱燕[1] LI Xuemei;ZHU Yan(School of Environment and Natural Resources, Renmin University of China, Beijing100872, China)

机构地区：[1]中国人民大学环境学院,北京100872

出　　处：《化学分析计量》2018年第3期36-39,共4页Chemical Analysis And Meterage

摘　　要：建立快速消解分光光度法测定污水中的化学需氧量(COD)。通过对样品消解时间、消解温度、冷却时间及测定波长的验证,确定了最佳测定条件:消解温度为165℃,消解时间为10 min,检测波长为610 nm。同时,对该方法的成本进行了核算。COD质量浓度在50~1 000 mg/L的污水范围内与吸光度有良好线性关系,相关系数为1.000,方法检出限为10.5 mg/L。样品的加标回收率为98~102%,测定结果的相对标准偏差为0.45%~1.51%(n=6),每个样本的检测成本约3.18元。该方法快速、简便且成本低,可用于COD含量为50~1 000 mg/L的污水测定。A fast digestion-spectrophotometry for the determination of chemical oxygen demand（COD） in sewage was established. By the verification of samples digestion time, digestion temperature, cooling time and the wavelength of determination, the best determination conditions were determined the digestion temperature of 165 ℃ , the digestion time of 10 min, the wavelength of 610 nm. The cost of the method were also assessed. The mass concentration of COD had a good linear relationship with the absorbance in the range of 50-1 000 mg/L with the correlation coefficient of 1.000, and the detection limit was 10.5 mg/L. The recoveries of samples were 98%-102%, and the relative standard deviations of the results were 0.45%-1.51%（n=6）. The cost of the method was 3.18￥ per sample. This method is fast, simple and low cost. It can be used for the determination of sewage with COD content of 50-1 000 mg/L.

关 键 词：快速消解 分光光度法 污水 化学需氧量 

分 类 号：O661.1[理学—分析化学]