- 作者: Yi-yang Shena, Quan-min Lib and Wei Weib
- 中文摘要:
aDepartment of Chemistry, Luoyang Teachers College, Luoyang, Henan 471002, People’s Republic of China
bKey Laboratory of Environment Science and Engineering Education Commission of Henan,
Department of Chemistry, Henan Normal University, Xinxiang, Henan 453002, People’s Republic of China
A new method of indirect determination of ascorbic acid with ammonium sulfate and ethanol by extraction and flotation of copper in the presence of thiocyanate has been studied in this paper. The study shows that a small amount of Cu(II) is reduced to Cu(I) by ascorbic acid, then Cu(I) precipitates with SCN-. In the course of phase separation of ethanol from water, the precipitated CuSCN is extracted and stays in the interface of ethanol and water. A good linear relationship is observed between the extraction yield of Cu(II) and the amount of ascorbic acid. The detection limit for ascorbic acid is 1 ’ 10-5 M. Every parameter has been optimized and the reaction mechanism has been studied. The method is simple, rapid (5 min) and suffers from few interferences of common anions and cations. It has been successfully applied for the determination of ascorbic acid in pharmaceuticals and fruits. - 英文摘要: --
- 中文關鍵字: --
- 英文關鍵字: --