钾长石粉酸浸除铁废液资源化的实验研究

Treatment on Acid Leaching Wastewater from K-Feldspar Powders

钾长石粉经过硫酸或盐酸酸浸除铁后 ,废液中含有大量的金属离子和游离酸 .对废硫酸进行循环利用实验 ,钾长石粉铁的浸出率达到 88.3% .对酸浸废液进行蒸发结晶 ,分别制备得到了纯度为 94 .1%的绿钾铁矾和 74 %的三氯化铁 .用硫酸酸浸废液蒸发结晶后 ,铁的回收率为 70 .0 % ,钾的回收率为 96 .5 % ,整个工艺无需高温 ,无需加压 ,操作简单 ,具有高效、低能耗、低污染的特点 ,表明用本项技术处理酸浸废液行之有效 .分析认为 ,废液呈强酸性、溶液中存在大量Fe2 + 、碱金属离子含量偏低是蒸发结晶过程中形成绿钾铁矾而不是黄钾铁矾的主要原因 .

After sulfuric acid or hydrochloric acid leaching to remove iron from K-feldspar powders, the filtrate wastewater contains free acid and abundant useful metal ions such as iron. The leaching proportion of iron from K-feldspar powders is 88.3% after treated by the used sulfuric acid. With a purity of 94.1% and 74% respectively, voltaite crystal and solid FeCl_3 have been produced by crystallizing in a lower temperature following the vaporization of the wastewater, with 70% iron and 96.5% potassium recovered. No need of high temperature and pressure, and with high efficiency, low energy loss and less pollution, this process proves its effectiveness. The strong acidity, Fe^(2+) and rather lower concentration of alkalis ions are responsible for voltaite, not jarosite, crystallizing from the acidic iron-bearing water.