季铵盐改性磁性凹凸棒的制备及其吸附性能研究

Preparation of Magnetic Organic Modified Attapulgite and Study of Its Adsorption on 1-naphthol

先用共沉淀法将Fe 3O 4纳米粒子沉积到凹凸棒土上,微波下用季铵盐十八烷基三甲基氯化铵(OTMAC)溶液对凹凸棒土进行改性。对改性后的凹凸棒土进行XRD、VSM、SEM等结构表征,结果表明OTMAC和Fe 3O 4纳米颗粒成功引入到凹凸棒土表面,并未改变凹凸棒土的内部结构。VSM测试结果表明改性后凹凸棒的饱和磁化强度为1.22 emu/g,表明其具有一定的磁性。吸附结果显示其符合准二级动力学方程,改性凹凸棒对1-萘酚的吸附等温线符合langmiur吸附等温方程,在热力学研究中,吸附过程的ΔG和ΔH为负值,表明所制备的凹凸棒土对1-萘酚的吸附是自发放热的行为。

In this study,attapulgite was modified with octadecyl trimethyl ammonium chloride(OTMAC)by using microwave-assisted technique,meanwhile,Fe 3O 4 nanoparticle was deposited on attapulgite by the chemical co-precipitation method.The prepared attapulgite were characterized in detail by XRD,VSM and SEM,the results show OTMAC and Fe 3O 4 nanoparticles successfully introduced into the surface of attapulgite,and the internal structure of attapulgite was unchanged.VSM measurement of modified attapulgite showed that the saturation magnetization was 1.22 emu/g,and it showed the prepared attapulgite had weak magnetic property.The results showed that the adsorption kinetic data fitted pseudo-second-order model well.The equilibrium data was more suitable to the Langmuir equations.The negative values ofΔG andΔH obtained from thermodynamic study indicated the spontaneous and exothermic nature of 1-naphthol adsorption on the prepared attapulgite.