Fe-Mn/浒苔生物炭复合材料对Pb^(2+)的吸附性能研究

Research on the Adsorption Performance of Fe-Mn/Enteromorpha Biochar Composites for Pb^(2+)

利用浒苔作为生物质原材料,通过浸渍法和热解法将KMnO_(4)和FeSO_(4)负载到原材料浒苔,制备Fe-Mn/浒苔生物炭复合材料(Fe/Mn-BC),所制备的材料具有一定的磁性,用BET、SEM-EDS、XRD、FTIR、XPS等表征手段对Fe/Mn-BC进行表征分析,发现材料呈现出不规则的多孔结构,主要为2~20 nm的介孔,表面负载许多小颗粒的聚集体且含有丰富的含氧官能团,这些都有利于对重金属铅离子的吸附;然后采用ICP分析法分析Fe/Mn-BC对Pb^(2+)的吸附速率、最大吸附量,其中,平衡吸附率最大可达到98.8%。通过研究其吸附等温线模型、吸附动力学模型、颗粒扩散模型,分析其对Pb^(2+)的吸附机理,结果表明,其吸附过程更符合伪二阶动力学模型和Langmuir吸附等温线模型,Fe-Mn/浒苔生物炭复合材料对Pb^(2+)的吸附是物理吸附和化学吸附的共同作用。

Using Enteromorpha as biomass raw materials,KMnO_(4) and FeSO_(4) were loaded into Enteromorpha by impregnation and pyrolysis to prepare Fe-Mn/Enteromorpha biochar composites.The prepared materials had certain magnetic properties.The Fe-Mn/Enteromorpha biochar composites were characterized by BET,SEM-EDS,XRD,FTIR and XPS.It was found that the materials showed irregular porous structure,mainly 2-20 nm mesoporous structure,aggregates loaded with many small particles and rich oxygen-containing functional groups,which were beneficial to the adsorption of heavy metal lead ions.Then the ICP analysis method was used to analyze the adsorption rate and maximum adsorption capacity of Fe-Mn/Enteromorpha biochar composites for Pb^(2+),in which the equilibrium adsorption rate was up to 98.8%.The adsorption mechanism of Pb^(2+)was analyzed by studying its adsorption isotherm model,adsorption kinetics model and particle diffusion model.The results showed that the adsorption process was more consistent with the pseudo second-order kinetic model and Langmuir adsorption isotherm model.The adsorption of Pb^(2+)by Fe-Mn/Enteromorpha biochar composites was the combination of physical adsorption and chemical adsorption.