关键词: 草酸钾改性, 产品表征, 吸附试验, 动力学模型, 等温吸附模型, 还原络合

Abstract: Modificated macadamin nut charcoal was prepared from macadamia nut and potassium oxalate. The microstructure， pore structure， functional group and graphitization degree of the product were characterized by SEM， SAP， FTIR and Raman spectroscopy analysis. The adsorption law of Cr（VI） on macadamia nut charcoal was investigated by adsorption test， kinetic simulation and adsorption isotherm fitting. The results showed that: ①The surface pore structure of macadamia nut charcoal is relatively small and smooth before modification. The surface of macadamia nut charcoal is obviously rugged and roughness and porosity increase after modification. The modification greatly increased the specific surface area and pore volume of macadamia nut charcoal， and reduced the pore size， which was beneficial to improve the adsorption performance of macadamia nut charcoal. ② The structure of macadamia nut charcoal remained relatively intact before and after modification， and the peak strength ratio ID/IG increased and the graphitization degree decreased after modification. ③The adsorption rate of Cr（VI） on modified macadamia nut charcoal is always higher than that on unmodified macadamia nut charcoal. Acidic conditions are favorable for Cr(VI) removal. The adsorption rate of Cr（VI） increases with the increase of adsorbent dosage and adsorption time， and then reaches saturation. The adsorption rate of Cr（VI） decreases with the increase of initial Cr（VI） concentration. ④ The adsorption kinetics was described and predicted by quasi-second-order kinetic model. The isothermal adsorption process of Cr（VI） on macadamia nut charcoal conforms to Langmuir equation， and the electrostatic attraction and reduction complexation of Cr（VI） are the main adsorption mechanisms.

Key words: potassium oxalate modification, product characterization, adsorption tests, dynamical model, isothermal adsorption model, reduction of complexing