用褐铁矿制备聚硅氯化硫酸铁的研究

Study on preparation of poly-silicic-ferric chloride sulfate using limonite

通过正交实验研究了用盐酸、硫酸、褐铁矿和硅酸钠制备聚硅氯化硫酸铁（PSFCS）絮凝剂的工艺条件。实验结果表明，浸取时间为2.5-3 h，浸取温度为110℃，硫酸浓度为6 mol/L，盐酸浓度为3 mol/L，质量液固比为4∶1，铁的浸出率可达95.7%-96.3%。溶液中加入少量聚乙烯醇作稳定剂，亚硝酸钠作氧化催化剂。PSFCS的合成条件：Fe/Si摩尔比为2，硅酸活化pH值为2，硅酸活化时间是30-40 min，陈化时间是2-2.5 h。与聚合硫酸铁（PFS）和聚合氯化铝（PAC）比较了处理印染废水的效果，表明PSFCS具有良好的絮凝性能，COD和浊度的去除率分别可达81.4%和96.1%。

The processing conditions of using hydrochloric acid, sulphuric acid, limonite and sodium silicate as raw materials to prepare poly-silicic-ferric chloride sulfate （PSFCS） flocculant are discussed by means of the perpendicular experiment. The experimental result shows that under the condition of lixiviating time being 2.5-3 hours, lixiviating temperature being 110℃ , sulphuric acid thickness being 6 mol/L, hydrochloric acid thickness being 3 mol/L, liquid-to-solid quality ratio being 4：1 , the extraction rate of iron will reach 95.7% - 96.3% in mass fraction. In the experiment, ounce stabilizing agent pva and oxidation catalyst sodium nitrite were added into the solution. The synthesis condition of PSFCS were ： Fe-to-Si tool ratio being 2, silicic acid activation pH being 2, silicic acid activation time being 30 - 40 minutes, ageing time being 2 - 2.5 hours. Compared with the performance of polymerization ferric sulfate （PFS） and polyaluminium chloride （ PAC）, the result indicates that PSFCS has good flocculation performance, and can purge the dyeing wastewater effectively, the removal rates of the turbidity and COD can reach 81.4% and 96. 1% respectively.