In order to further explore the adsorption mechanism of chromium ion by biochar, organic components (OCs) and inorganic components (ICs) of biochar (RC) were prepared, and adsorption experiments of chromium ions by these types of carbon (RC, OC, IC) were performed. The three types of carbon were characterized before and after adsorption of chromium ions, using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Boehm titration, and zero charge (pH_pzc). Results showed that the adsorption efficiency of IC on trivalent chromium (Cr³⁺) was the strongest, ion exchange of Cr³⁺ with metal cations present on IC being the main adsorption mechanism, accounting for 61% of the total adsorption capacity. Among the metal ions, K⁺ accounted for about 51%. The REDOX between Cr³⁺ and carboxyl accounted for 20% of the total adsorption capacity. Other adsorption mechanisms, such as chelation between Cr³⁺ and carboxyl, and co-precipitation between Cr³⁺ and carbonate, occupied a small proportion. OC showed the largest adsorption capacity to hexavalent chromium (Cr⁶⁺). The adsorption mechanism of OC to Cr⁶⁺ was the result of combined actions, such as electrostatic attraction, and REDOX between Cr⁶⁺ with the aromatic π-conjugated system and reductive functional groups like hydroxyl. Among them, the REDOX accounted for 53% of the total adsorption of Cr⁶⁺ by OC.

为了进一步探索生物炭对铬离子的吸附机理，制备了生物炭（RC）的有机组分（OCs）和无机组分（ICs），并研究了这些类型的碳（RC，OC，IC）对铬离子的吸附实验。 ）进行。使用傅立叶变换红外光谱（FTIR），X射线光电子能谱（XPS），Boehm滴定法和零电荷（pH _pzc）表征了三种类型的碳在吸附铬离子之前和之后的特征。结果表明，IC对三价铬（Cr ³⁺）的吸附效率最高，主要吸附机理为Cr ³⁺与金属阳离子的离子交换，占总吸附量的61％。在金属离子中，K⁺约占51％。Cr ³⁺和羧基之间的REDOX占总吸附容量的20％。Cr ³⁺和羧基之间的螯合以及Cr ³⁺和碳酸盐之间的共沉淀等其他吸附机制所占的比例很小。OC对六价铬（Cr ⁶⁺）表现出最大的吸附能力。OC对Cr ⁶⁺的吸附机理是由于Cr ⁶⁺与芳香族π共轭体系和羟基等还原性官能团之间的静电吸引和REDOX等共同作用的结果。其中，REDOX占OC对Cr ⁶⁺的总吸附的53％。