蒙脱土/聚丙烯酰胺杂化絮凝剂制备及絮凝性能研究

Preparation and flocculation performance of a polyacrylamide/montmorilonite hybrid flocculant

利用十六烷基三甲基溴化铵(CTAB)与钠基蒙脱土(Na-MMT)的阳离子交换反应制得有机化蒙脱土(O-MMT),通过硝酸铈铵引发丙烯酰胺单体在有机化蒙脱土片层间原位插层聚合制得蒙脱土/聚丙烯酰胺(MMT/PAM)杂化物.同时,研究了引发剂用量、聚合反应时间和蒙脱土含量对杂化物特性粘数的影响,并用XRD、FTIR、TEM对Na-MMT、O-MMT和MMT/PAM杂化物进行结构表征.最后实验对比了MMT/PAM杂化物与PAM对三氧化二铬悬浮液的絮凝效果.XRD、TEM结果显示,纳米尺寸大小的蒙脱土均匀地分散在PAM基体中.絮凝实验结果显示,添加质量分数0.5%～5.0%MMT的MMT/PAM杂化物的絮凝效果优于纯PAM.

Organophilic-montmorillonite（O-MMT）was prepared by a cation exchange reaction between inorganic ions of montmorillonite and annmonium cations of cetyl trimethyl ammonium bromide（CTAB）.Montmorilonite/polyacrylamide（MMT/PAM）hybrid was then prepared via intercalation polymerization of acrylamide among the lamellae of O-MMT initiated by cerium ammonium nitrate,（NH4）2Ce（NO3）6.The effects of initiator dosage,polymerization time and MMT content on the intrinsic viscosity of the MMT/PAM hybrid were investigated.The structures of Na-MMT、O-MMT and MMT/PAM hybrid were characterized by means of X-ray diffraction（XRD）、FTIR,transmission electron microscopy（TEM）,and the flocculating effects of MMT/PAM hybrid and pure PAM on chromium trioxide suspension were compared.The results showed that nano-sized MMT was dispersed evenly in the polyacrylamide matrix,and the flocculating effect of MMT/PAM hybrid was better than that of pure PAM for 0.5% chromium trioxide suspension when the MMT content was kept at 0.5%～5.0%.