酸溶测定铬矿石中三氧化二铬含量

摘要

以硫酸-磷酸-高氯酸混酸分解试样,高氯酸的强氧化性可以促进铬矿石的分解,加快铬矿石的溶解。试液在5%～6%的硫酸酸度及银盐的存在下,用过硫酸铵氧化,以苯基邻铵基苯甲酸为指示剂,用硫酸亚铁铵标准溶液滴定。通过用标准物质验证以及与标准方法进行比对,本法测定结果稳定、可靠,可以满足日常检验要求。%The mixed acid of sulfuric acid - phosphoric acid - perchloric acid were used to decomposit the samples, strong oxidizing of perchloric acid, can promote the decomposition of chromium ore to speed up the dissolution of chromium ore. The test solution in the presence of 5% - 6% sulfuric acid acidity and silver, ammonium persulfate oxidation, phenylanthranilic ammonium acid as indicator, was titrated with ferrous ammonium sulfate standard solution. Through vev- ifying with standard reference materials and comparing with the determination result was stable and reliable and met the daily inspection requirements.