An ion exchanger was prepared by sulfonation of cork-waste chars. The exchange properties of the resultant material were characterized using Na+, Ca2+ or Fe3+ aqueous solutions. The content of metal ions in the soluti...An ion exchanger was prepared by sulfonation of cork-waste chars. The exchange properties of the resultant material were characterized using Na+, Ca2+ or Fe3+ aqueous solutions. The content of metal ions in the solutions were determined by atomic absorption spectrometry. On the basis of the results obtained, the chemical equilibrium and its thermodynamic aspects related to the ion exchange process were studied. It was found that equilibrium constant K varies by the order: Na+<Ca2+<Fe3+, its value increasing with increasing temperature, and that △H°>0 and △5°>0, with -△G° following the sequence: Ca2+>Na+>Fe3+.展开更多
The separation of Ca2+and Mg2+ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer.This paper studied the adsorption equilibrium,kineti...The separation of Ca2+and Mg2+ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer.This paper studied the adsorption equilibrium,kinetics,and dynamic separation of Ca2+and Mg2+ions by strong acid cation resin,and the effects of phosphoric acid and nitric acid on the adsorption process were investigated.The results reveal that the adsorption process of Ca2+and Mg2+ions in pure water on resin is in good agreement with the Langmuir isotherm model and their maximal adsorption capacities are 1.86 mmol·g-1 and 1.83 mmol·g-1,respectively.The adsorption kinetics of Ca2+and Mg2+ions on resin fits better with the pseudo-first-order model,and the adsorption equilibrium in pure water is reached within 10 min contact time,while at the present of phosphoric acid,the adsorption rate of Ca2+and Mg2+ions on resin will go down.The dynamic separation experiments demonstrate that the designed column adsorption is able to undertake the separation of metal ions from the mix acids aqueous solution,but the dynamic operation should control the flow rate of mix acid solution.Besides nitric acid solution was proved to be effective to completely regenerate the spent resin and achieve the recyclable operation of separation process.展开更多
文摘An ion exchanger was prepared by sulfonation of cork-waste chars. The exchange properties of the resultant material were characterized using Na+, Ca2+ or Fe3+ aqueous solutions. The content of metal ions in the solutions were determined by atomic absorption spectrometry. On the basis of the results obtained, the chemical equilibrium and its thermodynamic aspects related to the ion exchange process were studied. It was found that equilibrium constant K varies by the order: Na+<Ca2+<Fe3+, its value increasing with increasing temperature, and that △H°>0 and △5°>0, with -△G° following the sequence: Ca2+>Na+>Fe3+.
基金Supported by a grant from Tianji Coal Chemical Group Co.Ltd.(Project no.2012-1978)Shenzhen Batian Ecological Engineering Co.,Ltd.(Project no.2013-0909).
文摘The separation of Ca2+and Mg2+ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer.This paper studied the adsorption equilibrium,kinetics,and dynamic separation of Ca2+and Mg2+ions by strong acid cation resin,and the effects of phosphoric acid and nitric acid on the adsorption process were investigated.The results reveal that the adsorption process of Ca2+and Mg2+ions in pure water on resin is in good agreement with the Langmuir isotherm model and their maximal adsorption capacities are 1.86 mmol·g-1 and 1.83 mmol·g-1,respectively.The adsorption kinetics of Ca2+and Mg2+ions on resin fits better with the pseudo-first-order model,and the adsorption equilibrium in pure water is reached within 10 min contact time,while at the present of phosphoric acid,the adsorption rate of Ca2+and Mg2+ions on resin will go down.The dynamic separation experiments demonstrate that the designed column adsorption is able to undertake the separation of metal ions from the mix acids aqueous solution,but the dynamic operation should control the flow rate of mix acid solution.Besides nitric acid solution was proved to be effective to completely regenerate the spent resin and achieve the recyclable operation of separation process.
