非水光度滴定法测定钢中低碳

NON-AQUEOUS PHOTOMETRIC TITRATION OF CARBON IN STEEL

研究了非水滴定定碳法中非水吸收液的组成、指示剂的配比及滴定终点时溶液色泽的吸光度变化。结果表明,由乙醇、乙醇胺及不饱和多胺组成的非水体系对钢样燃烧时所释出的二氧化碳能最有效的吸收。试验选择了百里酚酞和茜素黄R的混合液为滴定指示剂,能给出敏锐的终点指示。在此基础上设计了一套非水定碳的自动分析装置。无论自动仪器或手工操作所得的分析结果都与标准值符合。方法应用于低含量碳的测定。

A rational study on the composition and constituents of five non-aqueous absorption solutions used in the photometric titration of carbon in steels was reported in this paper, It was found that a non-aqueous solution containing ethanol, ethanolamine and unsaturated polyamine showed most efficient for the absorption of CO_2 evolved upon combustion of steel samples, A mixture of thymolphthalein and alizarin yellow is chosen as indicator for the titration and is proved to have a sharp indication for the end point, An automatic analyzer is designed and manu factured based on this phenomenon. Results obtained by either the manual procedure or the automatic analyzer conform very well to the certified values especially for low carbon contents.