高压坩埚-草酸-盐酸羟胺法提取粘土中的游离氧化铁

Extraction of Free Iron Oxide From Clay by Pressure Crucible-Oxalic Acid-Hydroxylamine Hydrochloride Method

为更准确地测定粘土中的游离氧化铁,提出一个提取游离氧化铁的新方法.该方法是:在高压坩埚中用草酸和盐酸羟胺混合液作为提取剂,于130℃的密封条件下提取粘土中的游离氧化铁,浸提时间为0.5h.实验表明:本法较常用的连二亚硫酸钠-柠檬酸钠-重碳酸钠法能更有效地分解粘土中的铁的氧化物,使游离氧化铁的浸出更完全.方法的RSD小于2.5%.

A method for extracting and determing free iron oxide from clay is introduced in this paper. Inthis method, 0.1000 g clay sample was mixed with extratant containing 0.6 g H2C2O4·2H2O, 0.6 gNH2OH·HCl and 10.0 mL water in the pressure curcible was heated at 130℃ for 0. 5 h. Theexperimental result showed that this method could decompose iron-manganese nodule and magnetite etc.effeciently and extracte free iron oxide from caly more completely than dithionite-citrate-bicarbonate method.