ZnCl_(2)活化废旧涤纶基活性炭的制备及吸附性能

Preparation and adsorption properties of waste polyester-based activated carbon activated by ZnCl_(2)

为了实现废旧涤纶织物的资源化利用,通过ZnCl_(2)活化-高温热解的方法制备了废旧涤纶基活性炭(WPT-AC),采用XRD、FT-IR和BET等表征技术对其物相晶型、特征基团、比表面积和孔隙结构进行了表征,通过正交试验确定了制备WPT-AC的最优工艺,评价了WPT-AC吸附亚甲基蓝(MB)性能并分析了吸附机理。结果表明:在质量分数为45%的Zn Cl_(2)溶液、热解温度为900℃、升温速率为5℃/min和热解时间为90 min的最优工艺条件下,制备的WPT-AC比表面积高达1 089.72 m^(2)/g、产率为58.45%。丰富的孔隙结构有利于提高其对污染物的吸附。在WPT-AC投加量为2.0 g/L、MB初始质量浓度为500 mg/L、吸附温度为40℃、吸附时间为80 min的条件下,WPT-AC对MB的去除率为97.49%。WPT-AC对土霉素(CIP)同样具有较好的吸附效果,且Ni(Ⅱ)共存条件下由于静电吸引的存在有利于吸附性能的提高。准二级动力学模型和Langmuir等温吸附模型更适合拟合WPT-AC吸附MB过程。

In order to realize the resource utilization of waste polyester fabrics,waste polyester-based activated carbon(WPT-AC)was prepared by ZnCl_(2)activationhigh temperature pyrolysis method.The crystal phase,characteristic groups and specific surface area pore structure of WPT-AC were characterized by XRD,FT-IR and BET.The optimal process for preparing WPT-AC was determined by orthogonal experiment.The adsorption performance of WPT-AC for methylene blue(MB)was evaluated and the adsorption mechanism was analyzed.The results showed that the specific surface area of WPT-AC prepared under the optimal process conditions of 45%ZnCl_(2)solution,pyrolysis temperature of 900℃,heating rate of 5℃/min and pyrolysis time of 90 min was as high as 1089.72 m^(2)/g,and the yield was 58.45%.The abundant pore structure was beneficial to improve the adsorption of pollutants.The removal rate of MB by WPT-AC was 97.49%under the conditions of WPT-AC dosage of 2.0 g/L,initial concentration of MB of 500 mg/L,adsorption temperature of 40℃and adsorption time of 80 min.WPT-AC also had a good adsorption effect on oxytetracycline(CIP),and the presence of electrostatic attraction was beneficial to the improvement of adsorption performance under the condition of Ni(Ⅱ)coexistence.The quasisecondorder kinetic model and Langmuir isothermal adsorption model of WPT-AC were more suitable for fitting the MB adsorption process of WPT-AC.