蒲草叶基活性炭的制备及性能研究

以蒲草叶（CL）为原料、CO₂为活化剂，采用两步法制备蒲草叶基活性炭（CL-AC）。利用SEM和BET对CL-AC的结构和形貌进行表征。结果表明CL-AC具有发达的孔隙结构。活化温度800℃、活化时间20 min条件下制得的活性炭样品（CL-AC3）的比表面积最高，达到570.03 m²/g。5 000次循环后，CL-AC3的电容保持率为90.56%。当电流密度为0.5 A/g时，比电容达到111 F/g。采用单因素试验对CL-AC3吸附亚甲基蓝的条件进行优化，结果表明，较优吸附条件为吸附剂投加量12.5 mg、溶液初始质量浓度50 mg/L、温度303.15 K、吸附时间300 min，该条件下吸附量达到199.22 mg/g。亚甲基蓝在CAC上的吸附过程遵循准二级动力学模型和Langmuir等温线，吸附过程是自发吸热。

Preparation and Properties of Cattail-leaf-based Activated Carbon

Activated carbon(CL-AC) was prepared from cattail leaves(CL) by two-step procedures using CO₂ as activation agent.The structure and morphology of CL-AC were characterized by scanning electron microscopy and nitrogen adsorption.The activated carbon(CL-AC3) obtained under activation temperature 800 ℃ and activation time 20 min had the maximum specific surface area(570.03 m²/g).And CL-AC3 resulted in outstanding capacitance retention of 90.56% over 5 000 cycles.The specific capacitance reached 111 F/g at the current density of 0.5 A/g.The adsorption conditions of methylene blue on CL-AC3 were optimized by single factor test and the optimum conditions were absorbent 12.5 mg, initial mass concentration of methylene blue 50 mg/L, temperature 303.15 K and time 300 min, under these conditions the adsorption capacity reached 199.22 mg/g.The adsorption process and equilibrium of methylene blue on CAC closely obeyed the pseudo-second-order kinetic model and Langmuir isotherm.The adsorption was endothermic, spontaneous, and a physically controlled process.