以油页岩渣为原料,经950℃煅烧4 h, 加入3.30 mol/L NaOH溶液于100℃处理4 h,用HCl酸化至pH 8~9时,SiO2的浸出率为75.8%.经X射线荧光分析,白炭黑产品中的SiO2纯度为91.8%;经FT-IR检测白炭黑的化学结构为水合二氧化硅;经XRD分析,白碳黑为无定型结构;TEM图像显示白炭黑的形貌近似为球状粒子,平均粒径在50 nm以下.白炭黑的比表面积(BET)为114 m2/g, pH值为5.5~6.0,加热减量为5.82%, 1000℃灼烧减量为6.16%,产品符合中国行业标准HG/T 3061-1999的要求.
Oil shale residue as a raw material of producing precipitated silica was firstly calcined for 4 h at 950 ℃ and treated by NaOH solution with 3.30 mol/L for 4 h, and then acidified by HC1 until the pH value of solution was up to 8-9, the leaching rate of SiO2 in the residue reached 75.8%. The SiO2 purity in the precipitated silica product was 91.8% by X-ray fluorescence analysis. The chemical structure of precipitated silica was hydrated silicon oxide through FT-IR analysis. The structure of precipitated silica was amorphous by XRD analysis. The TEM micrograph showed that the shape of precipitated silica particles was nearly spherical, and the average grain diameter was less than 50 nm. The specific surface area of precipitated silica was 114 m^2/g, pH was 5.5-6.0, heating loss was 5.82%, loss on ignition at 1000 ℃ was 6.16%. The product could be comparable with the requirements of HG/T 3061-1999 industrial product standard.