Zong Yiming, Wang Xinxiang, Zhang Hao, Li Yan, Yu Jian, Wang Chen, Cai Zhantao, Wei Jincheng, Ding Lei
School of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China.
School of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China; Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education, Anhui University of Technology, Ma'anshan 243032, China.
Int J Biol Macromol. 2023 Apr 15;234:123637. doi: 10.1016/j.ijbiomac.2023.123637. Epub 2023 Feb 11.
A ternary composite (SA/GE@BC) for cadmium removal from wastewater was successfully prepared. The alginate and gelatin were successfully impregnated with biochar (derived from water caltrop shell) to improve the recyclability and adsorption capacity. The prepared SA/GE@BC demonstrated a good removal for cadmium at pH 4.0-7.0 conditions. The cadmium removal increased with increasing SA/GE@BC dosage. The adsorption kinetics process was well consistent with the pseudo-second order model. And the Langmuir model (R > 0.99) best described the isotherm data. The calculated adsorption capacity reached a maximum of 86.25 mg/g. The adsorption was a spontaneous and endothermic process, and elevating temperature favored the removal of cadmium. The alginate-gelatin composition enhanced the number of oxygenated functional groups and exchangeable ions. This enhanced the removal of cadmium by complexation and cation ion exchange. Also, the removal mechanism of cadmium on SA/GE@BC involved electrostatic attraction and π-bond coordination. The saturated SA/GE@BC could be well regenerated by 0.1 M HNO. All these results suggested the preparation of SA/GE@BC could effectively use waste resources to produce highly effective adsorbents for removing cadmium from contaminated water.
成功制备了一种用于去除废水中镉的三元复合材料（SA/GE@BC）。海藻酸钠和明胶成功地负载了生物炭（由菱角壳制备），以提高其可回收性和吸附能力。制备的SA/GE@BC在pH 4.0 - 7.0条件下对镉具有良好的去除效果。镉的去除率随SA/GE@BC用量的增加而提高。吸附动力学过程与准二级模型高度吻合。Langmuir模型（R > 0.99）能最好地描述等温线数据。计算得到的吸附容量最高可达86.25 mg/g。吸附是一个自发的吸热过程，升高温度有利于镉的去除。海藻酸钠 - 明胶组合物增加了含氧官能团和可交换离子的数量。这通过络合和阳离子交换增强了镉的去除效果。此外，镉在SA/GE@BC上的去除机制涉及静电吸引和π键配位。饱和的SA/GE@BC可用0.1 M HNO₃很好地再生。所有这些结果表明，SA/GE@BC的制备能够有效地利用废弃资源生产出用于从污染水中去除镉的高效吸附剂。
