硫酸烧渣酸浸液制备氧化铁红的工艺研究

Study on Preparation of Ferric Oxide Red from Sulfuric Acid Leaching Solution

以硫酸烧渣为原料,经酸浸、氧化、沉铁、除杂、煅烧制备α-Fe2O3。研究了沉铁、除杂和煅烧工艺,优化了工艺条件。结果表明,在初始铁离子浓度为1.81 mol/L,H2O2与Fe2+摩尔比为0.9,体系pH值为6.0,反应温度为35℃,反应时间为2.5 h的条件下,铁回收率为97.5%;使用过量NaOH溶液搅拌洗涤氢氧化铁,Al含量可低至0.02%;在750℃煅烧3 h,可获得纯度为97.7%的红棕色氧化铁红产品。

As an effective comprehensive utilization method of sulfuric acid slag,α-Fe2O3 was prepared using sulfuric acid leaching liquid as raw materials via oxidation,precipitation,impurity removal and calcining.The above process conditions were investigated and optimized respectively.The results showed that the iron recovery rate can reach 97.5%under the conditions:initial iron concentration was 1.81 mol/L,the molar ratio of H2O2 to Fe2+was 0.9,system pH value was 6.0,reaction temperature was 35℃and aging time was 2.5 h.Excessive NaOH solution was used to stir and wash iron hydroxide,and Al content could be as low as 0.02%.Under the condition of calcining temperature 750℃and calcining time 3 h,the purity of reddish-brown iron oxide red product could reach 97.7%.