摘要
对Cu(DDTC)_2+Hg^(2+)=Hg(DDTC)_2+Cu^(2+)褪色反应,加入另一种显色剂进行显色反应Cu^(2+)+2BCO=Cu(BCO)_2,在450nm处测量Cu(DDTC)_2吸光度的减少,600nm处测量Cu(BCO)_2吸光度的增加,以两处吸光度差值的和作Hg^(2+)的定量测定,从而建立了测定微量汞的双显色剂双波长分光光度法。该方法的ε=3.7×10~4 L·mol^(-1)·cm^(-1)。检出限为0.14ppm,标准物质检验的相对误差和变异系数分别小于2%和5%。
A novel dual-colour reagent and dual wavelength spectrophotometric method for the determination of mic-roamounts of mercury is established by adding another colour reagent -biscyclohexanone- oxaldihydrazine (BCO) to the reacting system of mercury and copper di-ethyl-dithiocarbamate complex (Cu(DDTC)_2). The decrease of the absorbance (A_1) of Cu(DDTC)_2 and the increase of the absorbance ( A_2) of Cu (BCO)_2 are determined at 450nm and 600nm respectively,and mercury is determined from the summation of A_1and A_2. Beer's law is obeyed for mercury ranging 0～200μg/25mL. The molar absorptivity is 3. 7×10~4L·mol^(-1)·cm^(-1). The detection limit is 0.14ppm. The standard reference material was determined with relative errors less than 2% and the coefficient of variation less than 5%.
出处
《分析试验室》
CAS
CSCD
北大核心
1992年第2期32-34,共3页
Chinese Journal of Analysis Laboratory
关键词
汞
中心离子交换
分光光度法
Dual-color reagent and dualwavelength spectrophotometry
Mercury determination
