Recognitions And Adsorption Of Hair Based Carbon Materials

With the rapid development of economy,the waste of resources and environmental pollution are becoming more and more serious.Carbon materials as an excellent material for adsorption of metal ions.The carbon material with nitrogen-containing functional groups has become a hot spot in current research due to the stronger adsorption capacity.Depend on the excellent adsorption capacity,nitrogen-containing activated carbon have received considerable attention and researches.The human hair has the characteristics of wide fuel source and low prime cost.In this study,hair served as a basic raw material and KOH as activator for nitrogen-doped activated carbon manufacturing AC_H.It was characterized by infrared spectroscopy and elemental analysis.The recognition of Al（III）and Fe（III）in rare earth and the adsorption of Pb（II）and Cr（III）by four carbon materials were studied by static specific surface sorbent.AC_H-400-1,AC_H-600-2,AC_H-500-2,AC_H-500-1-500-1 prepared in this study have excellent internal pore structure and rich nitrogen content.The BET specific surface area of AC_H-400-1,AC_H-600-2,AC_H-500-2-500-2 and AC_H-500-1-500-1 are 162.21,143.38,390.70 and 378.16 m²/g,respectively.The nitrogen content of them are 9.23%,1.93%,6.01%,8.32%,respectively.The prepared carbon materials,AC_H-400-1-400-1 and AC_H-600-2,have exhibits good adsorption and recognition properties for Fe（III）and Al（III）,due to the advanced pore structure and rich nitrogen-containing functional groups.The adsorption capacity of AC_H-400-1-400-1 toward Al（III）are4.35 mg/g,the adsorption capacity of AC_H-600-2-600-2 toward Fe（III）are 15.54 mg/g.The adsorption behavior conformed to the second-order kinetics modeland the Freundlich adsorption model.The adsorption capacity of selected samples increases with the value of pH and the dosage of absorbent.In the temperature range studied,the higher the temperature was,the larger theadsorption capacity of Fe（III）was,whereas the opposite was true for Al（III）.The selectivity coefficient of AC_H-400-1-400-1 towards Al（III）with respect to La（III）was 6.9,AC_H-600-2-600-2 towards Fe（III）with respect to La（III）was 8.3.The removal efficiency of AC_H-400-1,AC_H-600-2-600-2 was 93%,98%,respectively.The adsorption capacity of AC_H-500-2-500-2 and AC_H-500-1-500-1 to Pb（II）and Cr（III）was 28.8mg/g and33.68 mg/g,respectively.The adsorption behavior conformed to the second order kinetic model and Freundlich monolayer adsorption.The adsorption capacity of selected samples increases with thevalue of pH,dosage of absorbent and temperature.The removal efficiency of AC_H-500-2,AC_H-500-1-500-1 was 96%,97%,respectively.The results of study manifested that AC_H-400-1,AC_H-600-2,AC_H-500-2-500-2 and AC_H-500-1-500-1 possesse better regeneration ability and reusability.