改性方式对膨润土性能及微粒助留助滤效果的影响

采用中性试剂氟化钠对钙基膨润土进行改性制备膨润土悬浮液和膨润土固体粉末,并分别与CPAM组成微粒助留体系。X-衍射分析表明,中性改性剂氟化钠在用量4%时都可以将膨润土中的Ca2 交换完全;透射电镜观察、膨胀倍、胶质价、粒度、粘度、Zeta电位测定和动态滤水实验表明,相对于膨润土固体粉末,膨润土悬浮液颗粒呈完全剥离的片状结构,具有更好的胶体与分散性能,粒度小、悬浮液流动性好且对二次纤维具有更好的助留助滤效果,尤其是放置四周后仍能保持其良好的助留助滤效果。

Effect of Bentonite Prepared by Modification Methods on Property and Microparticle Retention and Drainage

The bentonite modified in the form of concentrated fluid dispersion with fluoride sodium under the neutral condition and form microparticle retention with CPAM,which is compared with solid-powder bentonite.XRD analysis shows that calcium ions among the layers of bentonite are replaced completely by sodium ions when 4% of sodium fluoride(based on the weight of bentonite) is used as ion-exchanger.The morphology of the bentonite and its suspension properties were observed and evaluated by TEM and conventional analysis methods respectively.It is found that the sodium fluoride-modified bentonite is dispersed as single layered structure and exhibits better suspensibility and dispensability,smaller particle size as well as lower sludge viscosity than solid-powder bentonite.Naturally,the bentonite modified by sodium fluoride behaves better on improving the retention and drainage of the secondary fibers than the bentonite modified by solid-powder;especially it can sustain its good performance even after four weeks as a suspension.