论文部分内容阅读
合金钢、铁合金中硅的分析,目前均采用重量法和氟硅酸钾容量法。重量法,操作麻烦,分析周期长,因此氟硅酸钾容量法成为常用的定硅方法。但是,由于K_2SiF_6沉淀中残留酸和吸附离子难以除尽,易使测定结果偏高,近年来,人们从改进洗涤方法上从事研究,要达到除尽残留和吸附离子,必须充分洗涤,结果会造成K_2SiF_6沉淀溶失,致使测定结果偏低。本法采取:向试液中加过量的草酸钾溶液来络合Fe(Ⅲ)、Al(Ⅲ)、Ti(Ⅳ)等干扰离子,排除了它们的干扰。选用理想的溴甲酚紫酸碱指示剂,以碱液中和残留酸,并使K_2SiF_6沉淀转变成H_2SiO_3,
Alloy steel, ferroalloy in silicon analysis, are currently using the weight method and potassium fluosilicate capacity method. Gravimetric method, the operation is cumbersome, the analysis cycle is long, so the potassium fluosilicate capacity method has become a commonly used method of determining silicon. However, due to the residual acid and adsorbed ions in K 2 SiF 6 precipitation, it is difficult to eliminate the residual acid and the adsorbed ions. As a result, the determination result is apt to be high. In recent years, people have studied to improve the washing method. K_2SiF_6 precipitate dissolved, resulting in low measurement results. This law takes: To the test solution plus excess potassium oxalate solution to complex Fe (Ⅲ), Al (Ⅲ), Ti (Ⅳ) and other interfering ions, ruled out their interference. Use the ideal bromocresol purple alkali indicator to neutralize residual acid in the lye and make K 2 SiF 6 precipitate into H 2 SiO 3,