Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai, 200090, People's Republic of China.
Department of Biomedicine and Health, Shanghai Vocational College of Agriculture and Forestry, Shanghai, 201699, People's Republic of China.
Environ Sci Pollut Res Int. 2024 Apr;31(16):24250-24262. doi: 10.1007/s11356-024-32646-x. Epub 2024 Mar 4.
Biochar-derived dissolved organic matter (BDOM) has the potential to influence the environmental application of biochar and the behavior of heavy metals. In this study, the binding properties of BDOM derived from livestock manure biochar at different pyrolysis temperatures with Cu(II) were investigated based on a multi-analytical approach. The results showed that the DOC concentration, aromatics, and humification degree of BDOM were higher in the process of low pyrolysis of biochar. The pyrolysis temperature changed the composition of BDOM functional groups, which affected the binding mechanism of BDOM-Cu(II). Briefly, humic-like and protein-like substances dominated BDOM-Cu(II) binding at low and high pyrolysis temperatures, respectively. The higher binding capacity for Cu(II) was exhibited by BDOM derived from the lower pyrolysis temperature, due to the carboxyl as the main binding site in humic acid had high content and binding ability at low-temperature. The amide in proteins only participated in the BDOM-Cu(II) binding at high pyrolysis temperature, and polysaccharides also played an important role in the binding process. Moreover, the biochar underwent the secondary reaction at certain high temperatures, which led to condensation reaction of the aromatic structure and the conversion of large molecules into small molecules, affecting the BDOM-Cu(II) binding sites.
生物炭衍生的溶解有机物质（BDOM）有可能影响生物炭的环境应用和重金属的行为。本研究采用多种分析方法，研究了不同热解温度下畜禽粪便生物炭衍生的 BDOM 与 Cu(II)的结合特性。结果表明，在生物炭的低温热解过程中，BDOM 的 DOC 浓度、芳香度和腐殖化程度较高。热解温度改变了 BDOM 官能团的组成，从而影响了 BDOM-Cu(II)的结合机制。简而言之，在低和高的热解温度下，分别由类腐殖质和类蛋白物质主导 BDOM-Cu(II)的结合。源于低温热解的 BDOM 对 Cu(II)表现出更高的结合能力，这是由于在低温下，作为主要结合位点的羧基在富里酸中的含量和结合能力较高。在高温下，蛋白质中的酰胺仅参与 BDOM-Cu(II)的结合，而多糖也在结合过程中发挥重要作用。此外，生物炭在某些高温下会发生二次反应，导致芳香结构的缩合反应和大分子向小分子的转化，从而影响 BDOM-Cu(II)的结合位点。
