氮掺杂碳纳米片对亚甲蓝的吸附性能研究

Adsorption of methylene blue on N-doped carbon nanosheets

采用溶剂热法合成了一种氮掺杂碳纳米片,研究了其对水溶液中亚甲蓝染料的吸附性能。研究结果表明,制备的氮掺杂碳纳米片具有高效吸附亚甲蓝染料的性能;溶液pH值对亚甲蓝在氮掺杂碳纳米片上的吸附有显著影响,碱性条件下亚甲蓝的平衡吸附量接近酸性条件下的2.5倍;亚甲蓝水溶液的初始浓度对平衡吸附有一定的影响,在低浓度的情况下随着亚甲蓝溶液初始浓度的增加平衡吸附量增大,当浓度达到一定程度后亚甲蓝平衡吸附量不再有显著增大;对水溶液中亚甲蓝染料的吸附动力学研究表明,吸附动力学数据符合伪二级动力学模型;平衡吸附研究结果表明,吸附等温线符合Langmuir吸附模型。

N-doped carbon nanosheets were synthesized through solvothermal method. Dye removal experiments were performed and found that N-doped carbon nanosheets showed excellent methylene blue removal property. The effects of pH and initial concentration on methylene blue adsorption were also evaluated, and found higher pH value increased the equilibrium adsorption amount greatly. The equilibrium adsorption amount at pH 11.5 was 585 mg/g which was nearly 2.5 times higher than that at pH 4; the adsorption amount also increased in a certain degree with the increasing of MB initial concentration. The adsorption kinetic follows pseudo- second-order model and the adsorption equilibrium data fits Langmuir model well.