煤矸石酸浸废渣制白炭黑工艺中杂质影响研究

Effect of impurities on preparation of white carbon black from coal gangue acid-leaching residues

煤矸石酸浸提铝渣制备白炭黑,由于有少量的铝、铁和氯离子等杂质显著影响产品质量。对"低温纯碱共融-二氧化碳酸化法"制备白炭黑工艺过程中杂质的残留与杂质对硅酸钠碳化工艺的影响进行了探讨。结果表明:该工艺制备的硅酸钠溶液中铝对碳化反应影响较小;氯离子杂质会生成氯化钠夹带进白炭黑,难以分离,可通过调节分散剂乙醇的浓度来消除氯离子的影响,最佳乙醇浓度为1 mol/L。采用X荧光光谱仪、激光粒度测试仪、X射线衍射仪、扫描电子显微镜等对制备的白炭黑产品的组成、粒径、形貌等进行表征,结果表明所制得的白炭黑产品符合HG/T 3061—2009标准。

Coal gangue acid-leaching residues has potential to be used as the silica source of the white carbon black.However, the existence of the impurities such as Al, Fe, and Cl can somehow decrease product＇s quality.In production process of white carbon black by ＇soda low-temperature co-melting reaction-carbon dioxide acidification＇ process, the impurity remains and the effect of these impurities on the sodium silicate carbonization process have been widely discussed.Results indicated that the Al in the prepared sodium silicate solution had little affect on carbonization reaction.While ,since the Cl maintained in the solution will form NaCl and mingled together with the product, which was hard to separate, the ethanol concentration could be adjusted to eliminate the influence of Cl- and the optimal concentration of ethanol was 1 mol/L.The compostion, particle size, and morphology of the as-prepared sample were analyzed by X-ray fluorescence spectrometer,laser particle size tester, infrared spectrometer, X-ray diffractomer, and SEM, respectively.Results showed the as-prepared white carbon black product met to the standard of HG/T 3061--2009.