碱木质素接枝聚丙烯酰共聚物对重金属吸附行为的影响

Absorption of Alkali Ligningrafted Acryloyl Copolymer for Pb(Ⅱ), Cd(Ⅱ) and Cu(Ⅱ)

以工业粗碱木质素为原料接枝丙烯酰胺、N,N-亚甲基双丙烯酰和丙烯酸3种不同单体,通过自由基共聚反应成功制备3种碱木质素接枝丙烯酰共聚物。测定了碱木质素接枝聚丙烯酰胺(AL-g-PAM)、碱木质素接枝聚亚甲基双丙烯酰胺(AL-g-PNIPAM)、碱木质素接枝聚丙烯酸(AL-g-PAA)和聚丙烯酸(PAA)对Pb^(2+)、Cb^(2+)和Cu^(2+)3种离子的时间动力学曲线、吸附等温线、循环洗脱解吸率和多元体系竞争吸附能力。结果表明:3种碱木质素接枝丙烯酰共聚物的时间动力学曲线遵循假二级动力学方程;吸附等温线数据遵循弗莱因得利希模型。二元离子竞争吸附体系中吸水倍率较大的PAA与AL-g-PAA对二元体系的吸附Kd值较吸水倍率低的AL-g-PNIPAM和AL-g-PAM更大;三元离子体系中4种复合凝胶对Cd^(2+)的吸附Kd值最大,而单离子体系中4种复合凝胶对Pb^(2+)的吸附Kd值最大。

Alkali lignin grafted acryloyI copolymer was prepared byradical copolymerizationwithligningraftedmonomerofacrylamide, N, N-methylenebisacryl and acrylic acid. The kinetics curve, adsorption isotherm, the desorption rate of cyclic desorption and the competitive adsorption capacity of the multicomponent heavy metal ion system was studied. The results show that kinetics curve of the lignin grafted acryloyl copolymer abide by the pseudo-second-order kinetics equation The adsorption isotherm data was followed by the Freundilch model. In the singleion system, the Kd value of Pb^2＋ionsis more than other ions for lignin grafted acryloyl copolymer and PAA. In the binary ion system, the Kd value of PAA and AL-g-PAA that have strong property for swelling and water absorption is more than AL-g-PNIPAM and AL-g-PAM. In the ternary ion system, the Kd value of Cd^2＋ionsare more than other ions tbr lignin grafted acryloyl copolymer and PAA.