高温高压下硫铁矿还原Fe^(3+)制备绿矾的研究

Preparation of Copperas by Reducing Fe^(3+) with Pyrite at High Temperature and High Pressure

在高压釜中用硫铁矿还原硫铁矿烧渣与硫酸反应所得酸浸液中Fe3+,当酸浸液组成为c(Fe3+)=2.6525 mol/L、c(Fe2+)=0.1125 mol/L、c(H+)=1.2300 mol/L、反应温度为250℃、液固比为25∶1、反应时间为30 m in时,Fe3+还原率达到100%。酸浸液pH≤0时,产生灰色FeSO4.H2O沉淀物;酸浸液pH≥0.5时,有碱式盐Fe2(SO4)2(OH).5H2O和复盐Na3Fe(SO4)3.H2O等沉淀物生成。该方法制备所得绿矾样品质量好于GB 10531-89优等品,并且具有工艺简单、反应速度快,还原率高等优点。

Copperas was prepared in a high-pressure kettle, using pyrite to reduce Fe^3＋ from acidic leaching solution of pyrite cinders reacted with sulfuric acid. The reduction ratio of Fe^3＋ reached 100% when the ion concentrations in the acidic solution were as follows ： c （ Fe^3＋ ） = 2. 6525 mol/L, c （ Fe^3＋ ） = 0.1125 mol/L and c （ H ^＋ ） = 1. 2300 mol/L, while the reaction temperature was 250 ℃, the ratio of solution volume to pyrite mass was 25：1 and the reaction duration was 30 min. A gray sediment of FeSO4 · H2O can be produced when pH value of acidic leaching solution is less than 0, and sediments like Fe2 （SO4）2 （OH） · 5H2O and Na3 Fe（ SO4 ）3 · H2O can be produced when pH value of the solution is higher than 0.5. This approach shows advantages like simplified processes, fast reaction speed and high recovery,and the copperas prepared by this method exhibited better quality than the top-grade products complying with Chinese National Standard of GB 10531 - 89.