两性聚丙烯酰胺的制备及其絮凝性能

Preparation of Amphoteric Polycrylamide and Its Flocculation Property

开发了一种对非离子聚丙烯酰胺进行改性制备两性聚丙烯酰胺(APAM)絮凝剂的新方法。以硅藻土悬浮液为絮凝对象,考察了改性反应中影响APAM絮凝效果的因素。结果表明,采用无水乙酸与三甲胺、环氧氯丙烷合成季胺盐型阳离子剂的方法优于采用盐酸的方法;在10mL质量分数为10%、相对分子质量为3×106的非离子型聚丙烯酰胺水溶液中加入8mL浓度为2.6mol/L的阳离子剂,同时控制V(NaOH)∶V(NaClO)为0.44,改性得到的APAM絮凝性能最佳,在pH3～9的较宽范围内对硅藻土悬浮液有较好的絮凝效果。在pH为3、APAM加入量为1.8mg/L时,硅藻土悬浮液的絮凝率可达100%。

A new method for preparing amphoteric polyacrylamide （APAM）, a kind of fiocculant, by modification of nonionic polyacrylamide was developed. Using diatomite suspension as flocculating object,the modification factors affecting the fiocculation properties of APAM were investigated. The results indicate that the method for synthesizing quarternary ammonium cationics using absolute acetic acid,trimethylamine and epichlorohydrin is better than that of using hydrochloric acid. When 8 mL solution of cationics with mass concentration of 2.6 mol/L is added into 10 mL aqueous solution of nonionic polyacrylamide with mass fraction of 10% and relative molecular mass of 3 ×10^6, and the volume ratio of NaOH to NaClO is controlled to be 0.44, the APAM prepared by modification has the best flocculating property and its flocculating efficiency on diatomite suspension is better in a wide range of pH 3-9. When pH is 3 and the dosage of APAM is 1.8 mg/L, the fiocculation rate of diatomite suspension can reach 100%.