混合焙烧法制备多孔氧化硅

为了缓解石棉工业废渣的排放压力,实现石棉尾矿的资源化利用,以陕南石棉尾矿为原料,采用混合焙烧法制备了多孔氧化硅材料,并采用XRD、SEM、BET等对其结构、形貌、比表面积及性能进行了表征。结果表明:500 ℃下混合焙烧2 h制备的多孔氧化硅结晶状况较好,多孔性良好,比表面积为40.23 m²/g,适合用于工业有机废水的处理。在中性环境下,废水中罗丹明B浓度为25 mg/L、吸附时间30 min时多孔氧化硅对罗丹明B的吸附率最大。

Preparation of Porous Silica by Roasting Asbestos Tailings Mixed with Ammonium Bisulfate

In order to reduce the waste discharge from asbestos industry and realize the utilization of asbestos tailings, a porous silica material was prepared by roasting method with asbestos tailings as raw material mixed with ammonium bisulfate. The structure, morphology, specific surface area and performances of the samples were characterized by means of X-ray diffraction, scanning electron microscope and BET. The results indicated that the porous silica was prepared after the roast process for 2 h at 500 ℃ by mixing with ammonium bisulfate. It possesses a good crystal structure and good porosity, with a specific surface area of 40.23 m²/g, which is suitable for the purification of industrial organic waste water. With the concentration of rhodamine B at 25 mg/L, adsorption at pH=7 for 30 min can result in the highest adsorption rate of rhodamine B on porous silica.