红土镍矿为原料制备白炭黑的最佳工艺研究

Study on the Optimum Technological Conditions of Preparing Silica White from Laterite Nickel Ore

以红土镍矿为原料,采用碱熔融-碳酸化分解方法制备出白炭黑产品。通过正交试验L9(34),找到碱熔融反应的最佳工艺条件:碱矿质量比150/50,反应温度823K,反应时间3.5h,原料粒度1.704μm。该条件下放大试验二氧化硅转化率为79.10%。浸出液经碳酸化分解制得白炭黑产品符合国家HG/T3065-1999标准。碳酸化分解后所得溶液经苛化工艺实现碱和二氧化碳的循环利用。

Silica white was prepared from laterite nickel ore by the method of molten NaOH - carbonization decomposition. The optimum technological conditions were found through alkali melting reaction orthogonal experiment L9 （3^4 ） to be ： a mass ratio of alkali vs. ore 150/50, reaction temperature of 823 K, reaction time of 3.5 h and material particle size of 1. 704μm. The extraction ratio of SiO2 in enlarged experiment reached 79.10%. The silica white product obtained by the carbonation decomposition of leached solution conforms to the state standard of HG/T3065 - 1999. The solution obtained by carbonation decomposition was causticized to recycle the alkali and carbon dioxide.