超声辅助法制备风化煤腐植酸-丙烯酸吸水树脂

Preparation of humic acid-acrylic acid absorbent resinfrom weathered coal by ultrasonic-assisted method

以风化煤提取的腐植酸(HA)和丙烯酸(AA)为原料,采用超声辅助-水溶液聚合法制备腐植酸-丙烯酸型高吸水性树脂(HA-PAA),通过正交实验确定吸水树脂的最佳聚合条件,并对其在盐溶液、酸碱性溶液、20~80℃环境下的耐性以及树脂的反复吸液性能进行测试,了解其适用性,并用红外光谱和扫描电镜对HA-PAA进行了结构表征。结果表明,超声辅助法制备HA-PAA的最佳条件为:超声辅助合成温度为55℃、m(AA)∶m(HA)=20∶1、pH值=2.0、MBA用量为8×10^-4g。在此条件下聚合的HA-PAA在5次吸水性能测试中仍保持良好,较PAA提高了90%以上;对盐溶液、酸碱性及一定范围内的温度环境表现出较好的耐受性,对纯水最大吸收倍率为771.6 g/g,对盐水最大吸收倍率为122.4 g/g;表征结果表明HA与AA充分发生了聚合反应,添加HA增加了PAA的亲水基团;HA-PAA聚合后生成明显孔洞,比表面积增大;制备出的HA-PAA吸水率提升有利于实际过程中的应用。

With humic acid(HA)extracted from weathered coal and acrylic acid(AA)as raw materials,HA-acrylic acid superabsorbent resin(HA-PAA)was prepared by ultrasonic-assisted aqueous solution polymerization,and the most absorbent resin was determined by orthogonal experiment.Its resistance to salt solution,acid-alkaline solution,20~80°C environment and repeated imbibitions of resin performance were tested to study its applicability.The structure of HA-PAA was characterized by infrared spectrum and scanning electron microscope.The results showed that the optimal conditions for preparing HA-PAA by ultrasonic-assisted method were ultrasonic-assisted synthesis temperature of 55℃,m(AA)∶m(HA)of 20∶1,pH of 2.0 and MBA dosage of 8×10^-4g.The HA-PAA polymerized under these conditions remained good in the five-time water absorption performance test,which was more than 90%higher than that of PAA.It showed better tolerance to salt solution,acid-base and a certain range of temperature environment,with the maximum absorption rate of 771.6 g/g for pure water and 122.4 g/g for brine.The characterization results show that HA and AA had fully polymerized and adding humic acid increased the hydrophilic group of PAA.The HA-PAA generated obvious pores and increased specific surface area after polymerization.The increased water absorption of HA-PAA after polymerization was beneficial to practical application.