改性金刺梨渣生物炭吸附亚甲基蓝性能研究

Study on Adsorption of Methylene Blue by Modified Biochar From Rosa Roxburghii Residue

采用KOH活化法制备改性金刺梨渣生物炭(RRT-K),并以亚甲基蓝(MB)为目标降解物,考察不同吸附时间、生物炭投加量、MB初始浓度、pH对RRT-K吸附MB的影响。通过扫描电镜(SEM)、傅里叶红外光谱(FTIR)及N2-吸附脱附等对生物炭的结构、形貌进行表征,并对其吸附动力学和等温吸附进行探讨。结果表明,与未改性炭(RRT)相比,RRT-K呈多孔结构,比表面积从3.3184 m^(2)·g^(-1)增加到4.9442 m^(2)·g^(-1)。吸附过程符合准二级动力学,吸附行为符合Langmuir模型,RRT-k对MB的吸附主要是以化学吸附为主的单层吸附。

The modified rosa roxburghii residue biochar(RRT-K)was prepared by KOH activation method.Methylene blue(MB)was used as the target degradation substance.The effects of adsorption time,dosage of biochar,initial concentration of MB and pH on the adsorption of MB by RRT-K were investigated.The structure and morphology of biochar were characterized by scanning electron microscopy(SEM),Fourier infrared spectroscopy(FTIR)and N2-adsorption and desorption,and the adsorption kinetics and isothermal adsorption were discussed.The results showed that RRT-K had a porous structure compared with unmodified carbon(RRT),and its specific surface area increased from 3.3184 m^(2)·g^(-1)to 4.9442 m^(2)·g^(-1).The adsorption process conformed to the quasi second-order kinetics,and the adsorption behavior conformed to the Langmuir model.The adsorption of MB by RRT-K was mainly a single layer adsorption based on chemical adsorption.