Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, 1800# Lihu Avenue, Wuxi, 214122, China.
Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, 215009, China.
Environ Sci Pollut Res Int. 2021 Aug;28(32):44064-44078. doi: 10.1007/s11356-021-13788-8. Epub 2021 Apr 12.
This work focused on using attapulgite and chitosan as raw materials to improve the adsorption capacity of Cd from the aqueous phase by optimizing the preparation experimental parameters. The modification parameters (attapulgite-chitosan mass ratio, calcination temperature, and time) were specifically studied and optimized. The results indicated that the mass ratio of attapulgite to chitosan was 1:4, the calcination temperature was 300 °C, and the calcination time was 1 h. Both raw and functionalized attapulgite samples were characterized by nitrogen adsorption-desorption isotherms at 77 K, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and zeta potential analysis. A series of adsorption experiments showed that the pseudo-second-order kinetic model and Langmuir adsorption isotherm better corresponded with the adsorption characteristics of the newly prepared adsorbent, and the maximum adsorption amount of Cd was 109.30 mg/g. Moreover, the effects of the pH value and coexisting cations on the Cd adsorption in aqueous solution were investigated. Adsorption mechanism of Cd on adsorbent might attribute to complexation, ion exchange reaction, and self-polarization.
本工作以凹凸棒土和壳聚糖为原料，通过优化制备实验参数，重点研究了改性参数（凹凸棒土-壳聚糖的质量比、煅烧温度和时间）对从水溶液中吸附 Cd 的吸附容量的影响。结果表明，凹凸棒土与壳聚糖的质量比为 1:4，煅烧温度为 300°C，煅烧时间为 1 h。对原土和功能化凹凸棒土样品进行了氮气吸附-解吸等温线、X 射线衍射、傅里叶变换红外光谱、扫描电子显微镜和 zeta 电位分析。一系列吸附实验表明，新制备的吸附剂的吸附特征更符合准二级动力学模型和 Langmuir 吸附等温线，Cd 的最大吸附量为 109.30 mg/g。此外，还研究了 pH 值和共存阳离子对水溶液中 Cd 吸附的影响。Cd 在吸附剂上的吸附机理可能归因于配位、离子交换反应和自极化。
