煤矸石酸浸废渣制备白炭黑的工艺研究

白炭黑是白色粉末状无定形硅酸和硅酸盐产品的总称，其用途十分广泛。煤矸石酸浸提铝后所得废渣中含有大量的二氧化硅（质量分数为80%~90%），以其为原料制备白炭黑可有效利用资源，变废为宝。研究以煤矸石提铝废渣与碳酸钠在750~850 ℃下熔融反应、200 ℃下高压水溶得到硅酸钠溶液，通过碳分制得白炭黑。实验得到最佳碳分工艺条件：硅酸钠硅钠比为1.5（Na2O与SiO2物质的量比）、硅酸钠质量浓度为1.07 g/cm3、添加剂乙醇为4 mol/L、聚乙二醇（PEG）为1.11×10-5 mol/L、十六烷基三甲基溴化铵（CTAB）为9×10-4 mol/L。结果表明，在最佳条件下得到的白炭黑产品性能最佳。

Preparation technology of white carbon black from acid-leached residue of coal gangue

White carbon black is the general term of all the white powdered amorphous silica and silicates， which can be used widely in multiple fields.The acid-leached residue of coal gangue getting from the aluminum extraction process contains 80%~90% SiO2（mass fraction），which is a main raw material of white carbon black.In this study，acid-leached residue reacted with sodium carbonate in the molten state at 750~850 ℃，then sodium silicate solution was obtained under high water pressure at 200 ℃.White carbon black was finally prepared through carbonization process.The optimized process conditions were obtained be as follows: sodium/silicate ratio was 1.5（amount-of-substance ratio of Na2O to SiO2），mass concentration of sodium silicate was 1.07 g/cm3，additives of ethanol concentration was 4 mol/L，PEG concentration was 1.11×10-5 mol/L， and CTAB concentration was 9×10-4 mol/L.Results showed the white carbon black performed best prepared under the optimal conditions.