Key Laboratory of Condition Monitoring and Control for Power Plant Equipment, Ministry of Education, North China Electric Power University, Beijing 102206, PR China.
Key Laboratory of Condition Monitoring and Control for Power Plant Equipment, Ministry of Education, North China Electric Power University, Beijing 102206, PR China.
Bioresour Technol. 2019 Nov;291:121859. doi: 10.1016/j.biortech.2019.121859. Epub 2019 Jul 22.
The adsorption mechanisms of Pb(II) and Cd(II) in aqueous solution using camellia seed husk biochars pyrolyzed at different temperatures were studied. The adsorption of Pb(II) and Cd(II) on biochars are mainly controlled by ion exchange, oxygen functional groups (OFGs) complexation, Pb(II)/Cd(II)-π interactions, and precipitation with minerals. Compared to the raw biochars, both carboxyl and phenolic hydroxyl groups increased in the biochars washed with HCl. However, the previous research ignored the effect of the increased OFGs. Thus, a revised method was proposed from this study to more accurately calculate the contribution of four different mechanisms. Precipitation with minerals was the dominant mechanism for Pb(II) and Cd(II) removal, accounting for 80.61-89.03% and 53.57-75.84%, respectively, of the total adsorption as the pyrolysis temperature increased from 300 °C to 700 °C. As for oxygen functional groups complexation, the percentage of Pb(II) and Cd(II) removal were 4.76-8.55% and 11.34-29.59%, respectively.
研究了不同热解温度下茶籽壳生物炭对水溶液中 Pb(II)和 Cd(II)的吸附机制。Pb(II)和 Cd(II)在生物炭上的吸附主要受离子交换、含氧官能团（OFGs）络合、Pb(II)/Cd(II)-π 相互作用和与矿物质共沉淀控制。与原始生物炭相比，用 HCl 洗涤后的生物炭中羧基和酚羟基都增加了。然而，之前的研究忽略了增加的 OFGs 的影响。因此，本研究提出了一种改进的方法，以更准确地计算四种不同机制的贡献。随着热解温度从 300°C 升高到 700°C，矿物质共沉淀是去除 Pb(II)和 Cd(II)的主要机制，分别占总吸附量的 80.61-89.03%和 53.57-75.84%。对于含氧官能团络合，Pb(II)和 Cd(II)的去除率分别为 4.76-8.55%和 11.34-29.59%。
