文章通过正交试验得到合成聚硅酸锌絮凝剂的最优条件:二氧化硅百分含量为4%、锌硅摩尔比为1:1、活化时间45min、熟化时间60min。在最优条件合下成聚硅酸锌絮凝剂过程中的活化前、活化后和熟化后分别加入不同量的乙酸钠,研究乙酸钠作为稳定剂对聚硅酸锌絮凝剂稳定时间、絮凝性能的影响,以及乙酸钠及对不同锌硅比、合成pH值聚硅酸锌絮凝剂稳定时间和絮凝性能的影响。结果表明:乙酸钠能延长聚硅酸锌的稳定时间,但要降低其絮凝性能,在添加量小于3.3%时能去浊率维持稳定;能减小聚硅酸锌絮凝剂存放过程中去浊率降低和随pH值波动的变化幅度;不同锌硅摩尔比较,乙酸钠对锌硅摩尔比较低PZSS性能的影响更大;不同pH值时,乙酸钠对PZSS性能影响不同,在pH=2时影响最大。
The optimal synthesis conditions of poly-zinc-silicate were obtained as w(SiO2) 4%, n(Zn)/n(Si) 1:1, activation time 45 min, aging time 60min by orthogonal experiments. Then in the synthesis of poly-zinc-silicate by the obtained optimal conditions, sodium acetate with different contents were added at the time before activating, after activating and aging to re- search the effects of sodium acetate as a stabilizer on the stable time, flocculation performance of poly-zinc-silicate, and the effects of sodium acetate on the stable time and flocculation property of poly-zinc-silicate with different n(Zn)/n(Si), pH val- ue. Results indicated that sodium acetate can prolong the stability time but reduce the rate of removed turbidity of poly-zinc- silicate, the rate of removed turbidity of poly-zinc silicate can remain stable when the quantity of sodium acetate is lower than 3.3%; sodium acetate can reduce the amplitude with the change of pH and decreases fluctuation of the rate of turbidity during the storage poly-zinc-silicate. The effects of sodium acetate on PZSS are bigger when PZSS has a lower zinc silicon mole ra- tio, and effects of sodium acetate on PZSS are different at different pH, with the greatest effect at pH 2.