草酸氧钒中草酸根的络合滴定

Determination of Oxalate in Vanadyl Oxalate by Complexometry

1引言 草酸氧钒（VOC2O4·5H2O）是多种选择性氧化催化剂的前体，通过草酸氧钒的热分解可以产生具有催化活性的钒氧化物。

The EDTA （sodium ethylenediamine tetraacetate ） titration method for the determination of oxalate content in vanadium oxalate was proposed. The oxalate in sample was precipitated by CaCO3 solution after aging, filtering and washing, the calcium oxalate was dissolved in nitric acid, and the vanadium matrix in sample was removed by Na2CO3 solution in strong alkaline condition, and after filtration, the EDTA titration method was applied to determine the quantity of calcium, and then the oxalic acid root content in the oxalic acid oxygen vanadium can be calculated. The relative standard deviation （RSD, n = 8 ） of the method was less than 3%, and the recoveries of C2O4^2- were 98.9% -100.7%.