Acidic vinegar residue (VR) and toxic hexavalent chromium (Cr(VI)) are unfavorable substances due to their toxicity against the environment. In this study, modified biochar was prepared to investigate the removal mechanisms of Cr(VI). The results showed that ZnCl₂ could yield highly aromatic products with improved pore structures. The adsorption capacity of modified biochar reached the highest efficiency (236.81 mg g⁻¹) when the mass ratio of ZnCl₂/VR was 1, which is higher than the control (9.96 mg g⁻¹). In addition, Cr(VI) adsorption coexisted with physical and chemical adsorption. The mechanisms of modified biochar to Cr(VI) removal included electrostatic attraction, pore filing, reduction and surface complexation. Notably, as a fermented product, VR biochar was a nitrogen-rich product; the formation of the amino group could provide a direct solid site for Cr(VI) adsorption. Subsequently, amorphous silica could be converted into silanol to provide additional adsorption sites. This work establishes the theoretical basis for efficient Cr(VI) removal and VR reuse.

酸性醋渣 (VR) 和有毒的六价铬 (Cr(VI)) 是不利的物质，因为它们对环境具有毒性。在这项研究中，制备了改性生物炭来研究 Cr(VI) 的去除机制。结果表明，ZnCl ₂可以产生具有改进的孔结构的高度芳香的产物。_{当ZnCl 2} /VR的质量比为1时，改性生物炭的吸附量达到最高效率（236.81 mg g ^-1 ） ，高于对照（9.96 mg g ^-1）。此外，Cr(VI)吸附与物理吸附和化学吸附并存。改性生物炭去除 Cr(VI) 的机理包括静电吸引、孔隙填充、还原和表面络合。值得注意的是，作为发酵产品，VR生物炭是一种富氮产品；氨基的形成可以为Cr（VI）吸附提供直接的固体位点。随后，无定形二氧化硅可以转化为硅烷醇以提供额外的吸附位点。该工作为高效去除 Cr(VI) 和 VR 再利用奠定了理论基础。