以DMCS为硅源的新型聚硅氯化铁铝的形态分布与混凝性能

Study on morphological distribution and property of polymer ferric aluminum chloride silicate (PAFSC) flocculant synthesized from dimethyldichlorosilane (DMCS)

采用二甲基二氯硅烷(DMCS)为硅源,与氯化铁、氯化铝聚合制备新型聚硅氯化铁铝絮凝剂(PAFSC)。其形态分布和处理含藻水的混凝性能结果表明,该混凝剂的最优技术指标为n_(Fe)/n_(Al)=0.4,n_(Si)/n_((Al+Fe))=0.1,碱化度B=1.5,C_((Al+Fe))=0.1 mol/L,pH=2.898,熟化时间为24h的条件下,有效成分Fe_b、Al_b的含量最高,絮凝效果最好,PAFSC对浊度的净化效率可达98.6%。研究表明,二甲基二氯硅烷会产生很强的协同效应,使无机高分子絮凝剂PAFSC有效成分高,絮凝效果好。

Abst Environmental pollution and resources of exhaustion become more and more serious, and water pollution is one of the most serious problems. Coagulant plays the vital role in the resource and environment protection, and enhances the water quality. So studying novel inorganic-organic complex flocculant of polymer ＇of ferric aluminum chloride silicate （PAFSC） from dimethyldichlorosilane （ DMCS） is very important to solve practical problem of wastewater treatment. Using DMCS, iron（Ⅲ） chloride and aluminum （Ⅲ） chloride as materials, PAFSC was prepared. The optimal technical conditions of PAFSC are as follows： nFe/nSi = 0.4, nSi/n（Fe＋ Al） = 0.1, B = 1.5, C/（Al＋Fe） = 0.1 mol/L, pH=2.898, aging time is 24 hours, the rate and the time of agitation is 300 r/min, 1 hour separately. The iron and aluminum species distribution in PAFSC were investigated by Fe-Ferron and Al-Ferron timed spectrophotometric methods. The studying results of species distribution of PAFSC showed that the concentration of Alb and Feb is highest under the prepared optimum conditions. PAFSC has obvious superiority with less-dosage, floc quicker-sediment, wider pH, higher efficient of removing turbidity. PAFSC has higher efficient of removing turbidity. The Si affiliation can produce very strong be in conjunction with the effect. This make flocculant effectiveness of PAFSC, the validity composition is high, the result of flocculant is good. The results of coagulation-flocculation of PAFSC showed that the best purifying efficiency of turbidity are above 98.6 % in treating algae water. The conversion of A1h, Feb and the purifying efficiency of turbidity is changing from increasing to de- creasing with increasing B, nFe/nAl and nsl/n（Fe＋ Al）. Aging time has obvious effect on A1b, Feb and the purifying efficiency of turbidity before 24 hours, but has little influence on A1h, Feb and the purifying efficiency of turbidity in 24 hours. The studying results of coagulation-flocculation mechanism and species distribution show that PAFSC has chain lattice structure, very. high molecule weight, strong capability of electrical neutralization, strong adsorption, bridging and network capturing.