高温制备土霉素菌渣生物炭对铀尾矿库渗排水中铀的吸附效果与机理

以土霉素菌渣（oxytetracycline fermentation residue，OFR）为原料，在300~900 ℃（间隔100 ℃）条件下制备生物炭，研究高温（800~900 ℃）制备OFR生物炭对废水中铀的吸附效果与机理。结果表明：对于不同温度下制备的生物炭，随着温度的升高，OFR生物炭表面功能基团逐渐减少，Ca晶体形态由CaC₂O₄（300~400 ℃）转变为CaCO₃（500~700 ℃）、CaO（800~900 ℃），而这也导致了吸附效果的变化。当制备温度升至800~900 ℃时，OFR生物炭10 min吸附即可对南方某铀尾矿库渗排水中的铀达到98%以上去除率，且高温制备的OFR生物炭在较宽的pH范围（4.0~9.0）与铀初始浓度（0.8~3.0 mg/L）下，均能稳定达到大于98%的去除率，处理后上清液中铀浓度远低于铀矿冶辐射防护和辐射环境保护规定的排放标准。因此，高温制备OFR生物炭在铀尾矿库渗排水原位处理方面，展示了较好的应用前景。

Adsorption efficiency and mechanism of uranium in seepage of uranium tailing pond using biochar prepared from oxytetracycline fermentation residues at high temperature

Oxytetracycline fermentation residues (OFR) were used to prepare biochar under different temperatures (from 300 to 900 ℃ with an interval of 100 ℃) for uranium adsorption and removal in the wastewater, and the adsorption efficiency and mechanism were studied. The results showed that as the rise of temperature, the surface function groups of OFR biochar, prepared at different temperatures, were decreased gradually and the crystal morphology of Ca was transformed from CaC2O4 (300-400 ℃) to CaCO3 (500-700 ℃) and CaO (800-900 ℃), which leaded to the changes of removal efficiency. When the temperature was raised to 800-900 ℃, the biochar adsorption achieved more than 98% removal efficiency of uranium in seepage of a tailing pond in the South of China in 10 min. Further studies found that more than 98% of uranium could be removed under the condition of wide range of pH (4.0-9.0) and initial uranium concentration (0.8-3.0 mg/L), and the supernatant after treated was much lower than the limit of discharge standard stipulated by radiation protection and radiation environment protection in uranium mining and metallurgy. Therefore, OFR biochar prepared at high temperature showed a good application prospect in in-situ treatment of uranium tailings drainage.