• 关键词：生物炭  酸碱改性  磺胺噻唑  吸附

• 基金项目：国家自然科学基金（No.21307050）；兰州大学中央高校基本科研业务费专项资金（No.lzujbky-2016-162）

• 李蕊宁
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 王兆炜
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 郭家磊
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 赵夏婷
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 李艳
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 谢晓芸
• 兰州大学资源环境学院, 甘肃省环境污染预警与控制重点实验室, 兰州 730000

• 摘要：以马铃薯茎叶为原料， 采用限氧裂解法制备生物炭， 通过H₂SO₄和KOH处理制备酸、碱改性生物炭. 应用比表面积法（BET）、扫描电镜（SEM） 和红外光谱（FTIR） 研究了改性前后3种生物炭的结构与性质， 并通过单因素实验研究了吸附时间、温度、磺胺噻唑初始浓度、pH值等因素对原始及酸碱改性3种生物炭吸附磺胺噻唑效果的影响， 初步探讨了吸附机制. 结果表明， 3种生物炭对磺胺噻唑的吸附行为符合准二级动力学方程； 酸改性生物炭对磺胺噻唑的吸附等温线符合Temkin模型， 原炭和碱改性生物炭的吸附等温曲线符合Freundlich模型. 酸改性极大的提高了生物炭对磺胺噻唑的吸附能力， 最大吸附量为7.69 mg·g^-1， 是原炭吸附量的2.4倍； 溶液pH对3种生物炭吸附磺胺噻唑影响不明显. 热力学研究表明， 酸改性生物炭对磺胺噻唑的吸附为自发的吸热反应. FTIR分析表明， 酸改性生物炭表面有更多含氧官能团， 为磺胺噻唑的吸附提供了吸附点. 氢键、范德华力及偶极距力作用对生物炭吸附磺胺噻唑起到主要作用.

• Abstract：Biochar (BC) was prepared by pyrolyzing potato stems and leaves under a limited oxygen condition. Biochar was modified with H₂SO₄ and KOH, respectively. The structures and properties of raw and modified biochars were characterized by using Brunauer-Emmett-Teller (BET), Scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR). The effects of reaction time, temperature, initial concentration of sulfathiazole and pH on the adsorption behaviors were investigated by single factor experiments, which were used to preliminarily discuss adsorption mechanism. The results show that the three adsorption kinetics was fitted well with the pseudo-second order model. Temkin model can describe adsorption isotherm of sulfathiazole onto acid modified biochar better, but those of raw and alkali modified biochars were fitted well with Freundlich model. The adsorption capacity of acid modified biochar was greatly improved for sulfathiazole as 7.69 mg·g^-1, which was 2.4 times higher than that of raw biochar. There is no obvious change of adsorption capacity with the studied pH. Thermodynamic calculations indicated that the adsorption of sulfathiazole onto acid modified biochar was a spontaneous endothermic process. The acid modified biochar possessed more O-containing functional groups than other two biochars by FTIR analysis, which provided sulfathiazole molecules with adsorptive sites. The mechanisms of adsorption for sulfathiazole onto three biochars were attributed to a combination of hydrogen bonding, van der waals forces and dipole forces.

• Key words：biochars  acid/alkali modified  sulfathiazole  adsorption

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