Magnetic iron oxide nanoparticles can efficiently adsorb and remove arsenic from water,and can be separated by an external magnetic field.However,the preparation process of the material is generally complicated.In this study,magnetic iron oxide nanoparticles were prepared using a simple thermal decomposition method,and characterized with different techniques,and then their adsorption performance for As were investigated.The study showed that ferric acetate thermal decomposition at 250 ℃ under a nitrogen atmosphere produced nanoparticles with a particle size of about 10-12 nm.The BET specific surface area of the material is approximately 90 m2·g-1,with a predominant pore size distribution of 10-50 nm,and possessing a particle aggregate pore structure.The synthesized adsorbents can efficiently remove As from water in the pH range of 3-9,with the best performance achieved at pH 7.The adsorption isotherm fits the Langmuir model,with a maximum adsorption capacity of approximately 30 mg·g-1.The adsorption kinetics follow the pseudo-second order model,and the adsorption mechanism involves surface chemical coordination to form an innersphere complex,which is not affected by ionic strength.The common co-existing ions in groundwater have no significant effects on As removal.The ferric acetate thermal decomposition method can serve as a low-cost method for preparing magnetic iron-based arsenic adsorbents.
关键词
砷/纳米氧化铁/磁性吸附剂/水质净化/吸附
Key words
arsenic/nano iron oxide/magnetic adsorbent/water purification/adsorption
维普
万方数据