返滴定K_2Cr_2O_7法测定异丙醇

Determination of isopropanol by back titration of potassium dichromate

提出并研究了返滴定K2Cr2O7法测定异丙醇的新方法.在硫磷混酸介质和加热条件下,用过量的K2Cr2O7氧化异丙醇为丙酮,其过量部分以二苯胺磺酸钠作指示剂,用Fe2+标准溶液滴定.为校正K2Cr2O7氧化异丙醇反应的不完全性,确定了被测体系中异丙醇在0.5~1.6mg/mL之间,其校正系数(异丙醇的实际值与测定值之比)为1.060.

A new method for determination of isopropanol by back titration of potassium dichromate was proposed and investigated. In the medium of sulfuric acid and phosphoric acid, potassium dichromate can oxidate isopropanol forming acetone, and the excess potassium dichromate may be titrated by Fe^(2+) standard solution using sodium diphenylaminesulfonate as the indicator. The correction factor (the ratio of true value to observed value) is 1.060 in the range of 0.51.6mg/mL of isopropanol.The simple and convenient method was applied to determine isopropanol in actual samples.