A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coated γ-Fe203 particles. To evaluate the adsorption of Cu^2...A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coated γ-Fe203 particles. To evaluate the adsorption of Cu^2+ on the obtained resin NDMC- 1, another two magnetic resins NDMC-0 (the precursor of NDMC-1 without hydrolyzation) and NDMO-1 (the synthesized weak acid resin using oleic acid coated γ-Fe2O3) were chosen for comparison. The results showed that the carboxyl groups were formed after hydrolyzation, and NDMC-1 exhibited a greater adsorption capacity to Cu2~. The desorption experiment demonstrated that the desorption ratio at pH 2 (95.14%) was greatly higher than pH 3 (25.97%). Moreover, the magnetic resin NDMC-1 was proved to be stable at pH 2, extending the application of magnetic materials which were always considered to be acid-nor, resistant.展开更多
The removal of cadmium(Cd) from synthetic solutions by batch adsorption process was performed using eggshell powder, which is mainly composed of calcite(CaCO3). In order to optimize the adsorption process, a re- s...The removal of cadmium(Cd) from synthetic solutions by batch adsorption process was performed using eggshell powder, which is mainly composed of calcite(CaCO3). In order to optimize the adsorption process, a re- sponse surface methodology(RSM) based on Central Composite Design(CCD) was applied. Developed model for Cd removal yields(R, %) response was statistically validated by variance analysis(ANOVA) which showed a high de- termination coefficient value(R2=0.9889). According to Minitab software, the optimal conditions were found at tem- perature of 44℃, eggshell adsorbent dose of 2.98 g, initial Cd concentration of 36.74 mg/L and initial pH of 7. Under these conditions, the Cd removal yield was 98.76%. The deviation value of 1.24% confirms the validity of the model for the adsorption process optimization. The adsorption isotherm has been described by a Freundlich model. In addition, the predominant sorption mechanisms are the chemisorptions or precipitation(non-reversible) and ion ex- change(reversible).展开更多
基金support provided by Program for Changjiang Scholars,NSFC(Nos. 51178215 and 51208249)Jiangsu Nature Science Fund(Nos.BK2010006 and BK2011032)Joint Innovation Project for Production-Study-Research in Jiangsu Province(No.BY2012155) China
文摘A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coated γ-Fe203 particles. To evaluate the adsorption of Cu^2+ on the obtained resin NDMC- 1, another two magnetic resins NDMC-0 (the precursor of NDMC-1 without hydrolyzation) and NDMO-1 (the synthesized weak acid resin using oleic acid coated γ-Fe2O3) were chosen for comparison. The results showed that the carboxyl groups were formed after hydrolyzation, and NDMC-1 exhibited a greater adsorption capacity to Cu2~. The desorption experiment demonstrated that the desorption ratio at pH 2 (95.14%) was greatly higher than pH 3 (25.97%). Moreover, the magnetic resin NDMC-1 was proved to be stable at pH 2, extending the application of magnetic materials which were always considered to be acid-nor, resistant.
文摘The removal of cadmium(Cd) from synthetic solutions by batch adsorption process was performed using eggshell powder, which is mainly composed of calcite(CaCO3). In order to optimize the adsorption process, a re- sponse surface methodology(RSM) based on Central Composite Design(CCD) was applied. Developed model for Cd removal yields(R, %) response was statistically validated by variance analysis(ANOVA) which showed a high de- termination coefficient value(R2=0.9889). According to Minitab software, the optimal conditions were found at tem- perature of 44℃, eggshell adsorbent dose of 2.98 g, initial Cd concentration of 36.74 mg/L and initial pH of 7. Under these conditions, the Cd removal yield was 98.76%. The deviation value of 1.24% confirms the validity of the model for the adsorption process optimization. The adsorption isotherm has been described by a Freundlich model. In addition, the predominant sorption mechanisms are the chemisorptions or precipitation(non-reversible) and ion ex- change(reversible).