聚硅酸金属盐复合絮凝剂形貌结构及性能研究

Images and Structures as well as Properties of Polysilicate Sulfate

以硅酸钠、硫酸和硫酸盐为原料制备聚硅酸金属盐(PSMS)复合絮凝剂,通过红外光谱研究了金属元素与聚硅酸(PS)的相互作用情况,采用电子显微镜观察了PS、PSMS和相应简单金属盐(MS)的形貌,利用激光粒度分析仪分析了絮体粒径变化及破碎与恢复情况,并考察了PSMS在不同投加量下处理腐植酸模拟废水的效果。结果表明:PSMS的红外光谱图中有M—O—Si振动峰出现,扫描电镜显示PSMS的聚集单元表面异于PS的平滑,为细小不规整的晶体颗粒,并与相应硫酸盐(MS)形貌有一定关联。此外,无论是所形成絮体的粒径还是对腐植酸的去除效果,聚硅酸硫酸铝(PSAlS)和聚硅酸硫酸铁(PSFeS)均优于其它聚硅酸金属盐,PSFeS的絮体虽易破碎但破碎后恢复能力最好,且粒径最大而容易沉降。

Polysilicate sulfate was prepared with sodium silicate, sulfuric acid and sulfate as raw materials. Interaction between metallic element and polysilicic acid was observed by infrared spectrum. Images of polysilicic acid, polysilicate sulfate and sulfate were observed by an electromicroscope. Simulation laser particle size analyzer was used to analyze the size change, broken and recovery of floc, and the effects of polysilicate sulfate dealing with humic acid simulation wastewater were studied at different dosages. Results showed that vibration of M--O--Si existed in the infrared spectrums of PSMS. The surface of unit was small and not neat crystalline grains, different from the smooth of PS, and associated with the corresponding sulfate morphology. No matter the flocs size or removing effects, polyaluminium silicate sulphate （PSA1S） and polyferric silicate sulphate （PSFeS） were better than other polysilicate sulfate. The floc of PSFeS which was easy to break owned the best of recovery capability, and the flocs size was the biggest and easy to settle.