College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China; Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China.
College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
J Environ Manage. 2021 Jun 15;288:112388. doi: 10.1016/j.jenvman.2021.112388. Epub 2021 Mar 26.
In this study, we used xanthate to modify two waste biomass materials (corn cob and chestnut shell) and prepared them as biosorbents in one step for effectively removing Pb(II) from aqueous solutions containing only Pb(II) or Pb(II), Cu(II) and Cd(II). The two biosorbents were characterized by SEM, EDS, FTIR and Zeta potential analysis, and the results of the characterization were used to explore the adsorption mechanism of Pb(II) on biosorbents. We compare the Pb(II) removal ability of the two biosorbents and the investigated factors that affect Pb(II) removal. The results show that the adsorption capacity of xanthate modified corn cob (X-CC) and xanthate modified chestnut shell (X-CS) for Pb(II) is related to pH, reaction time, temperature and initial concentrations of both adsorbent and adsorbate. The adsorption of Pb(II) on X-CC and X-CS follows Langmuir isotherm equation and quasi-secondary kinetic equation, and their fitted q values are 166.39 and 124.84 mg g, respectively. The analysis shows that the biosorbent has high selectivity to Pb(II) rather than Cu(II) and Cd(II), and still maintains a high removal rate of Pb(II) in actual wastewater. The biosorbents remove metal ions mainly through ion exchange reaction and the functional group in the material complexes with the metal to form micro-precipitation. The high adsorption capacity in aqueous solution and low costs in the manufacturing process of the present biosorbents ensure that they have great potential in practical applications for treating heavy-metal contaminated surface water.
在这项研究中，我们使用黄原酸盐一步法修饰两种废生物质材料（玉米芯和板栗壳），将其制备成生物吸附剂，从仅含有 Pb(II) 或 Pb(II)、Cu(II) 和 Cd(II) 的水溶液中有效去除 Pb(II)。两种生物吸附剂通过 SEM、EDS、FTIR 和 Zeta 电位分析进行了表征，并利用表征结果探讨了 Pb(II) 在生物吸附剂上的吸附机制。我们比较了两种生物吸附剂对 Pb(II) 的去除能力以及影响 Pb(II)去除的各种因素。结果表明，黄原酸盐修饰玉米芯（X-CC）和黄原酸盐修饰板栗壳（X-CS）对 Pb(II) 的吸附容量与 pH、反应时间、温度和吸附剂及吸附质的初始浓度有关。Pb(II) 在 X-CC 和 X-CS 上的吸附符合 Langmuir 等温方程和拟二级动力学方程，拟合得到的 q 值分别为 166.39 和 124.84 mg/g。分析表明，该生物吸附剂对 Pb(II) 具有较高的选择性，而对 Cu(II) 和 Cd(II) 的选择性较低，在实际废水中仍保持较高的 Pb(II) 去除率。生物吸附剂主要通过离子交换反应去除金属离子，材料中的官能团与金属形成微沉淀。该生物吸附剂在水溶液中具有较高的吸附容量，且生产成本低，这确保了其在处理重金属污染地表水方面具有巨大的实际应用潜力。
