以小麦秸秆为原料，在300℃和500℃下制备生物质炭（WS300和WS500），对其性质进行表征，并研究其对Cr （VI）的吸附特性。结果表明随制备温度升高，生物质炭的C含量升高，缩合度增强，极性和亲水性减弱。WS500有更大的比表面积和孔容。Cr （VI）主要以HCrO₄^-和Cr₂O₇^2-的形态吸附在生物质炭表面。WS500有更为丰富的羟基、羧基、酯基等官能团，可与Cr （VI）发生络合、氧化还原等作用。Cr （VI）的吸附等温线更适合用Langmuir模型拟合，说明吸附主要是单分子层吸附。Cr （VI）在WS500上的吸附容量高于WS300。

Two types of wheat straw biochar were prepared under conditions of 300℃ (WS300) and 500℃ (WS500), then their physicochemical properties were characterized, and their adsorption characteristics of Cr(VI) were studied. The results showed that the higher the pyrolysis temperature, the higher the C content and condensation degree of biochar, while the lower the polarity and hydrophilicity. WS500 had a larger specific surface area and pore volume. Cr(VI) was mainly adsorbed on the surface of biochar in the form of Cr oxides such as HCrO₄^- or Cr₂O₇^2-. WS500 had more abundant functional groups such as hydroxyl, carboxyl and ester groups, which could undergo complexation, redox and other reactions with Cr(VI). The adsorption isotherm of Cr(VI) was more suitable for fitting with the Langmuir model, indicating that the adsorption process was mainly monolayer. The adsorption capacity of Cr(VI) on WS500 was higher than that on WS300.

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安徽省高校自然科学研究项目（2023AH050318、KJ2020A0040）和淮北师范大学科研项目（2023ZK009、2023ZK014）资助。