季铵型纤维素的红外光谱及对持久性有机污染物的吸附特征

IR Spectra of Quarternary Ammonium Cellulose and Its Adsorption Properties to POPs

文章研究了季铵型阳离子纤维素(QACC)的红外光谱和对持久性有机污染物的吸附及循环利用问题。研究了吸附工艺参数对QACC吸附容量的影响。研究了QACC对染料的吸附等温式,测定了QACC吸附染料过程的热力学参数(ΔH,ΔS,ΔG)、吸附速率常数和吸附活化能,探讨了QACC吸附机理。在近中性水溶液中,QACC对含磺酸基、羧基、羟基的水溶性芳香族有机污染物具有较大的饱和吸附容量,常见共存离子对吸附不产生影响。QACC对上述污染物的吸附既有化学吸附,也有物理吸附,而以化学吸附为主。吸附符合Langmuir等温式和一级动力学方程,吸附速率随温度升高而增大。水溶性有机污染物用0.5 mol.L-1氢氧化钠水溶液洗脱,再生后QACC可以循环利用。QACC是一种性能优良的新型功能材料,可应用于环境中持久性有机污染物的治理。

In the present paper, the IR spectra, adsorption and reusing property of quaternary ammonium cationic cellulose （QACC） towards POPs were studied. The method and technological parameters of adsorption were discussed. The adsorbing isotherm, thermodynamics （△H, △S and △G）, adsorption rate constant and adsorption activation energy of QACC on dyes were determined, and the sorption mechanism of QACC was confirmed initially, too. In near neutral water solution, QACC has a better saturated absorptive capability to water-soluble organic contaminations of aromatic series which contain carboxyl, sulfonic and hydroxyl group, and the presence of common coexistent ions in environmental water had no obvious effect on the saturated adsorption capacity of QACC. The adsorption involves both physical adsorption and chemical adsorption, and the chemical adsorption is the main. The adsorption of QACC to water-soluble organic contaminants followed Langmuir adsorption equation and oneorder kinetic equation. Furthermore the adsorption rate constants increase with increasing temperature. QACC could be desorbed and reused with 0.5 mol ·L ^-1 sodium hydroxide solution after adsorbing water-soluble organic contaminations. QACC is a new environmental function material with excellent performance and can be used to remove the POPs in the environment.