氯金酸钾制备及其热分解  

Preparation of Potassium Chloroaurate and Its Thermal Decomposition

作　　者：郑雅杰[1] 郭伟[1] 白猛[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《贵金属》2007年第3期1-5,共5页Precious Metals

摘　　要：采用双氧水盐酸混合溶金制得氯金酸溶液,在氯金酸溶液中加入氯化钾蒸发结晶得到桔黄色氯金酸钾晶体。研究表明,5g金粉中加入5倍理论量的双氧水和盐酸,100℃下搅拌反应20min,得到氯金酸溶液,溶液中加入理论量氯化钾,搅拌蒸发结晶得到KAuCl4.2H2O晶体。热重差热(TG-DTA)实验结果表明,样品在25～431.68℃有2个明显吸热过程和1个连续失重过程。根据X射线衍射(XRD)实验,329℃时KAuCl4.2H2O热分解固体产物为KAuCl4,376℃时KAuCl4热分解固体产物为Au和KCl。Potassium chloroaurate was prepared by evaporating and crystallizating the chloroaurate acid solution after the addition of potassium chloride, and the chloroaurate acid solution was produced through dissolution of gold powders with hydrogen peroxide and hydrochloric acid. 5g gold powders were dissolved completely at 100℃and for 20min when HCI and H2O2were 5 times theoretical dosage, respectively. The optimum dosage of KCI to HAuCl4 is a theoretical dosage. TG-DTA tests indicate that the sample has two distinct heat absorption processes and one continuous weight loss process from 25℃ to 431.68℃. XRD tests indicate that the KAuCl4·2H2O decomposes to KAuCl4 at 329℃ and KAuCl4 decomposes to KCI and Au at 376℃.

关 键 词：无机化学 双氧水 盐酸 氯金酸 氯化钾 氯金酸钾 热分解 

分 类 号：TQ131.23[化学工程—无机化工]