The adsorption properties, including the adsorption isotherms, thermodynamics and kinetics, of 1-amino-2- naphthol-4-sulfonic acid (1,2,4-acid) onto weakly basic resin ND900 are investigated. Both the Langmuir and Fre...The adsorption properties, including the adsorption isotherms, thermodynamics and kinetics, of 1-amino-2- naphthol-4-sulfonic acid (1,2,4-acid) onto weakly basic resin ND900 are investigated. Both the Langmuir and Freundlich equations can give a good fit to the adsorption isotherms, which indicates an endothermic and a favorable adsorption in our study range. A high yield in elimination of about 45.21 %-97.28% is obtained for the tested adsorption systems. The capacity and affinity of the adsorption increase with temperature, due to the phenomena of 'solvent-motivated' effects. The value of is 51.59 kJ/mol, which indicates a chemical adsorption and then expects the poor desorption property of ND900. The negative value of indicates the spontaneous nature of the adsorption process, and the positive value of shows the increased randomness at the solid/solution interface during the adsorption process. The value of the adsorption rate constant lower than 0.013 min-1 is indicative of a slow adsorption rate. The intra-particle diffusion must be one of the rate limiting steps.展开更多
基金The work is financially supported by the National Natural Science Foundation of China (No. 20274017)
文摘The adsorption properties, including the adsorption isotherms, thermodynamics and kinetics, of 1-amino-2- naphthol-4-sulfonic acid (1,2,4-acid) onto weakly basic resin ND900 are investigated. Both the Langmuir and Freundlich equations can give a good fit to the adsorption isotherms, which indicates an endothermic and a favorable adsorption in our study range. A high yield in elimination of about 45.21 %-97.28% is obtained for the tested adsorption systems. The capacity and affinity of the adsorption increase with temperature, due to the phenomena of 'solvent-motivated' effects. The value of is 51.59 kJ/mol, which indicates a chemical adsorption and then expects the poor desorption property of ND900. The negative value of indicates the spontaneous nature of the adsorption process, and the positive value of shows the increased randomness at the solid/solution interface during the adsorption process. The value of the adsorption rate constant lower than 0.013 min-1 is indicative of a slow adsorption rate. The intra-particle diffusion must be one of the rate limiting steps.