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铁矿石中Fe(Ⅱ)、Fe(Ⅲ)含量的测定及条件
摘 要
铁矿石经浓盐酸和少量的SnCl2溶液加热到45oC溶解后，用SnCl2—TiCl3还原滴定Fe（Ⅲ），使Fe（Ⅲ）还原为Fe（Ⅱ）。再以K2Cr2O7滴定全铁含量。本方法对实验操作温度，试样溶解酸的选择有一定的要求，宜选用非氧化性强酸在30—60oC溶解矿样。
关键词：SnCl2—TiCl3—K2Cr2O7；滴定法；铁矿石；Fe（Ⅱ）；Fe（Ⅲ）
目 录
摘要································································································1
引言································································································2
1试验部分······················································································2
１.1仪器与药品···········································································2
１.2方法原理···············································································2
１.3实验方法···············································································2
２结果讨论······················································································3
２.1、化学参数的影响····································································3
２.1.1、酸度的影响·······································································3
２.1.2、反应温度的影响·································································3
２.1.3、试剂用量的选择·································································3
２.1.4、反应时间的影响·································································3
３矿样的测定··················································································4
３.1、样品的处理···········································································4
３.2、样品的测定···········································································4
４结论·····························································································5
５视野拓宽······················································································6
参考文献····························································································6
引 言
铁在自然界中主要以Fe（Ⅱ）和Fe（Ⅲ）价态存在，两种价态的环境效应和生物效应有着很大的差别，Fe（Ⅱ）是人体重要营养素，而过多Fe（Ⅲ）对人体是有害的。因此，分别测铁的不同价态具有重要的意义。经典的K2Cr2O7法测定铁时，每一份试液中需加入饱和氯化汞溶液10mL，约有480mg的汞排入下水道，而国家环境部门规定汞排放的允许量0.05mg/L，要达到此允许排放量，至少要加入9.6—10t的水稀释。实际上汞盐
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