Laboratory of Biomass and Bioprocessing Engineering, College of Engineering, China Agricultural University, Box 191, Beijing 100083, China.
Laboratory of Biomass and Bioprocessing Engineering, College of Engineering, China Agricultural University, Box 191, Beijing 100083, China.
Bioresour Technol. 2018 Dec;270:545-553. doi: 10.1016/j.biortech.2018.09.078. Epub 2018 Sep 17.
This study investigated the key physicochemical characteristics of char that control its ability to absorb Pb. Three type of crop residue-derived chars and their ball milled powder were characterized using multiple approaches. The Pb sorption mechanisms of biochar were caused mainly by coprecipitation reactions, which were governed by ionic minerals on chars instead of mineral crystallization (e.g., SiO and AlO), while coprecipitation reactions and π electronic interaction were the dominant mechanisms of activated carbon. Pearson analysis showed that adsorption quantity (Q) highly correlated with the cation exchange capacity (CEC) (P < 0.01)/oxygen functional groups (OFGs) (P < 0.05) and Q closely correlated with coprecipitation amount (P < 0.01)/complexation amount (P < 0.01). Linear regression equations of sorption amount and CEC (R ＞ 0.8)/OFGs (R ＞ 0.7) were established. CEC and OFGs of chars are the key factors controlled Pb sorption. These results may promote the development of low-cost, engineered biochar with superior sorption qualities for environmental remediation.
本研究考察了控制炭吸附 Pb 能力的关键物理化学特性。采用多种方法对三种作物残余衍生炭及其球磨粉末进行了表征。生物炭对 Pb 的吸附机理主要是共沉淀反应，这是由炭上的离子矿物控制的，而不是矿物结晶（例如，SiO 和 AlO），而共沉淀反应和π电子相互作用是活性炭的主要机制。Pearson 分析表明，吸附量（Q）与阳离子交换容量（CEC）（P<0.01）/含氧官能团（OFGs）（P<0.05）高度相关，且 Q 与共沉淀量（P<0.01）/络合量（P<0.01）密切相关。建立了吸附量与 CEC（R>0.8）/OFGs（R>0.7）的线性回归方程。炭的 CEC 和 OFGs 是控制 Pb 吸附的关键因素。这些结果可能会促进开发具有优越吸附性能的低成本、工程化生物炭，用于环境修复。
