乙萘酚和甲萘胺在超高交联树脂上的竞争吸附

通过氯甲基化的苯乙烯-二乙烯苯共聚物的后交联反应制备了超高交联吸附树脂(NDA150),通过红外光谱和比表面孔径分析对NDA150和XAD-4树脂的结构和表面参数进行表征。通过等温吸附实验研究了水溶液中乙萘酚和甲萘胺在NDA150和XAD-4上的竞争吸附行为。结果表明,NDA150树脂具有较高的比表面积为1 144 m2/g和较丰富的微孔,而XAD-4树脂的比表面积为904 m2/g,且以中孔为主。通过等温线吸附实验可知,在单组分水体系中NDA150和XAD-4树脂对乙萘酚和甲萘胺都具有较好的吸附性能,303 K时,NDA150和XAD-4对乙萘酚的吸附量分别可达1.97和1.24 mmol/g;对甲萘胺的吸附量分别为2.33和1.45 mmol/g;吸附质在树脂上的吸附等温线符合Langmuir模型。在双组分水体系中乙萘酚和甲萘胺的物质的量之比为1:1(C0=2.0 mmol/L),树脂对两种吸附质的吸附量均减少,但是树脂对吸附剂的吸附总量大于相同平衡浓度下对单组分水溶液中乙萘酚和甲萘胺的吸附量。在303 K时,建立LCA模型来预测吸附质的竞争吸附,并对模型进行修正,用LCA修正模型的拟合效果较好。

Competitive adsorption of 2-naphthol and 1-naphthylamine onto hyper-crosslinked polymeric adsorbents

A new hyper-crosslinked resin NDA150 was prepared by post-crosslinking of chloromethylated PS-DVB.The physicochemical structure of NDA150 and XAD-4 was elaborately characterized using Fourier transform infrared spectroscopy(FTIR) and was further morphologically characterized using BET and BJH methods.Competitive adsorption performance of 2-naphthol and 1-naphthylamine from aqueous solutions on adsorbents were investigated.The results indicated that the specific surface areas of NDA150 and XAD-4 were 1 144 m2/g and 904 m2/g,and pore size distribution of NDA150 and XAD-4 mainly were micropore and middlepore.The adsorption performances and mechanism on adsorbents towards 2-naphthol and 1-naphthylamine were studied through the isotherm adsorption experiment.The isotherm adsorption results showed that adsorbents had good adsorption capabilities to 2-naphthol and 1-naphthylamine.The adsorption capacities of 2-naphthol on NDA150 and XAD-4 were 1.97 mmol/g and 1.24 mmol/g,and the adsorption capacities of 1-naphthylamine on NDA150 and XAD-4 were 2.33 mmol/g and 1.45 mmol/g at 303 K.The adsorption of 2-naphthol and 1-naphthylamine on NDA150 and XAD-4 were in accordance with Langmuir isotherm equations.When the amount of substance of two compounds is the same,the individual adsorption amounts in single systems were higher than those in binary systems,but the total adsorption amount in binary systems were larger than the individual adsorption amount in single systems.Under the condition of 303 K,equilibrium data for the binary systems adsorption were analyzed using Langmuir-competitive-adsorption (LCA) models,but the equations weren't fitted to data for the mixed solutions.The modified LCA model fit the binary adsorption equilibrium data satisfactorily and adequately,and by introducing modifier ρ,the modified LCA model fitting effect was good.