络合滴定法测定有机砷化合物中的砷

络合滴定法测定有机砷化合物中的砷 DETERMINATION OF ARSENIC IN ORGANOARSENIC COMPOUNDS BY LaCl 3 -EDTA YC1 3 -EDTA COMPLEXOMETRIC TITRATIONS 谢正秋 Xie Zhengqiu 1 2 first-author 陶莉 Tao Li 1 2 武汉大学化学系 武汉大学化学系 Department of Chemistry,Wuhan University Department of Chemistry,Wuhan University 武汉大学化学系,武汉,430072 武汉大学化学系,武汉,430072 介绍氧瓶或消化分解LaCl 3 -EDTA和YCl 3 -EDTA法测定有机砷化合物中砷的新方法。LACl 3 -EDTA法适用于氧瓶分解,样品含硫有干扰;YCl 3 -EDTA法不受SO 4 2- 干扰,因而还适用于以硫酸为主要消化剂的消化分解和测定。测定误差 < ±0.30％。 Arsenic in organic compounds was determined by LaCl3-EDTA or YC13-EDTA indirect complexometric titration. The LaCl3-EDTA method was properly used for oxygen flask decomposition （iodine-water as absorbent） and SO42- interference , but the YC13-EDTA method was also used for digestion decomposition using H2SO4-HNO3 as the di-gestion agent. The formation of LaAsO4 or YAsO4 was carried out in pH5. 5 and boiling tem-perature. After cooling, an equal amount of alcohol and appropriate xylenol orange were added and the excess of LaCl3 or YC13 was titrated with 0. 01 mol ?L-1 EDTA. The maximun deriation in the determination of As was ?.30%. 络合滴定 镧 钇 有机砷化合物 complexometric titration lanthanum yttrium organoarsenic compound O656.32 1994-06-01 2021-04-01 6