硫铁矿烧渣制备聚合硫酸铁新工艺

摘要

Acidic aqueous ferric sulfate was abstained by heating maturating, dissolving and filtration process of mixture of pyrite cinders and sulfur acid. Polymeric ferric sulfate was prepared after fresh hydroxide was added to the ferric sulfate solution, stirring for 2 hours at 25～60 ℃,then putting H2O2 in the solution. The alkali degree of PFS was increased as Fe(OH)3 reacted to Fe2(SO4)3 in the solution. The alkali degree was proportional to the amount of Fe(OH)3 at the constant Fe2(SO4)3. Higher temperature benefited this reaction. Fe2+ was completely converted to Fe3+ by adding H2O2 to the solution. The coagulation test testified that this polymeric ferric sulfate had good effect of removal turbidity. PFS was prepared from pyrite cinders not only utilizing a solid waste, but having advantages as follows, short reaction time, no pollution, good benefit with comparison to the preparation of PFS from FeSO4.%硫铁矿烧渣是硫酸制备过程中产生的固体废弃物．将硫铁矿烧渣与硫酸混合后,经过熟化、水溶、过滤得到酸性硫酸铁溶液．在硫酸铁溶液中,加入新制备的氢氧化铁,于25～60 ℃时反应2 h后加入少量双氧水得到聚合硫酸铁(PFS)．随着氢氧化铁与硫酸铁溶液反应的进行，溶液中PFS盐基度不断增加．当硫酸铁的量一定时，PFS盐基度随氢氧化铁的量增加而增加．温度升高时有利于PFS的生成．加入双氧水将溶液中的Fe2+转化为Fe3+，并且PFS盐基度增大．混凝实验说明该方法制备的PFS具有很好的除浊效果．利用硫铁矿烧渣制备PFS不仅消除了污染，而且使其固体废弃物得到了利用．该工艺与以FeSO4为原料、用NaNO2催化氧化法制备PFS的方法相比，具有反应快、无污染、经济效益好等优点．