A novel microwave digestion and alkali fusion assisted hydrothermal method was proposed to synthesize zeolite from coal fly ash and the zeolite product was studied for removal of Cd(II)from aqueous solution through ba...A novel microwave digestion and alkali fusion assisted hydrothermal method was proposed to synthesize zeolite from coal fly ash and the zeolite product was studied for removal of Cd(II)from aqueous solution through batch experiments.The adsorbent was characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,surface area analyzer and zeta potential measurement.The results show that the synthetic zeolite was identified as faujasite.The optimum conditions for removal of Cd(II)are found to be:adsorbent dose of0.5g/L,pH6,contact time of90min and initial concentration of20mg/L,the removal rate of Cd(II)is98.55%.The experimental kinetic data agree well with the pseudo second-order equation;the Langmuir isotherm model is found to be more suitable to explicate the experimental equilibrium isotherm results than Freundlich,Dubinin-Radushkevich and Temkin models,and the maximum adsorption capacity of Cd(II)is found to be86.96mg/g.The thermodynamic parameters such asΔGΘ,ΔHΘandΔSΘwere evaluated and the results show that the adsorption of Cd(II)onto the as-synthesized zeolite is spontaneous,endothermic and feasible under studied conditions.展开更多
The fly ashes(Class F and C)have been successfully used as the main substrates in the hydrothermal syntheses of Na-A,Na-P1,Na-X and sodalite zeolites.Both ashes and their derivatives after milling with magnetic field ...The fly ashes(Class F and C)have been successfully used as the main substrates in the hydrothermal syntheses of Na-A,Na-P1,Na-X and sodalite zeolites.Both ashes and their derivatives after milling with magnetic field grinder were used.The paper investigates the effect of fly ash fraction size on the syntheses efficiency and physicochemical properties of the obtained zeolites.The starting material and obtained zeolites were subjected to physicochemical characteristics using X-ray diffraction,X-ray fluorescence,particle size analysis,and scanning electron microscopy methods.The paper showed a significant effect of the used fly ash fractions on the quantity,purity,quality and level of crystallinity of the zeolites phase obtained.The application of the grinding process prior to the syntheses of zeolites,with a relatively small financial outlay,significantly increases their application potential.Obtained zeolites are a promising material in the context of their use,inter alia,in environmental protection.展开更多
基金Projects(2013BAC15B01,2013BAB07B03)supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of ChinaProject(Qian Ke He JZ[2014]2009)supported by the Key Foundation of Science and Technology of Guizhou Province,China
文摘A novel microwave digestion and alkali fusion assisted hydrothermal method was proposed to synthesize zeolite from coal fly ash and the zeolite product was studied for removal of Cd(II)from aqueous solution through batch experiments.The adsorbent was characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,surface area analyzer and zeta potential measurement.The results show that the synthetic zeolite was identified as faujasite.The optimum conditions for removal of Cd(II)are found to be:adsorbent dose of0.5g/L,pH6,contact time of90min and initial concentration of20mg/L,the removal rate of Cd(II)is98.55%.The experimental kinetic data agree well with the pseudo second-order equation;the Langmuir isotherm model is found to be more suitable to explicate the experimental equilibrium isotherm results than Freundlich,Dubinin-Radushkevich and Temkin models,and the maximum adsorption capacity of Cd(II)is found to be86.96mg/g.The thermodynamic parameters such asΔGΘ,ΔHΘandΔSΘwere evaluated and the results show that the adsorption of Cd(II)onto the as-synthesized zeolite is spontaneous,endothermic and feasible under studied conditions.
基金financed by The National Center for Research and Development contract No GEKON2/O2/266818/1/2015.
文摘The fly ashes(Class F and C)have been successfully used as the main substrates in the hydrothermal syntheses of Na-A,Na-P1,Na-X and sodalite zeolites.Both ashes and their derivatives after milling with magnetic field grinder were used.The paper investigates the effect of fly ash fraction size on the syntheses efficiency and physicochemical properties of the obtained zeolites.The starting material and obtained zeolites were subjected to physicochemical characteristics using X-ray diffraction,X-ray fluorescence,particle size analysis,and scanning electron microscopy methods.The paper showed a significant effect of the used fly ash fractions on the quantity,purity,quality and level of crystallinity of the zeolites phase obtained.The application of the grinding process prior to the syntheses of zeolites,with a relatively small financial outlay,significantly increases their application potential.Obtained zeolites are a promising material in the context of their use,inter alia,in environmental protection.
