Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier tra...Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysisof organic samples loaded with the acid shows that amine forms 1:1complex of ion-pair association with succinic acid, malic acid andmaleic acid, and 1:1, 2:1 complex of ion-pair association withfumaric acid. It is proposed that the complex forms depend on thesecond dissociation constant of the dibasic acid, pK_a2.展开更多
The extraction of cadmium and zinc with di-(2-ethylhexyl)-dithiophosphoric acid(D2EHDTPA)-toluene and D2EHDTPA-trioctyl amine(TOA)-toluene has been investigated. Infrared spectrum analysis, the nuclear magnetic resona...The extraction of cadmium and zinc with di-(2-ethylhexyl)-dithiophosphoric acid(D2EHDTPA)-toluene and D2EHDTPA-trioctyl amine(TOA)-toluene has been investigated. Infrared spectrum analysis, the nuclear magnetic resonance spectrum(NMR) analysis and conductivity measurements confirm that the probable structures of the extracted complexes are CdA2 and ZnA2. Cadmium can be extracted by D2EHDTPA very easily. Almost all the cadmium can be extracted, but stripping of cadmium from the organic phase is very difficult. When a mixture of D2EHDTPA and TOA is used, selective extraction of cadmium from zinc sulfate solution can be achieved. Cadmium can be easily stripped from the organic phase.展开更多
基金Supported by the National Natural Science Foundation of China (No. 29836130).
文摘Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysisof organic samples loaded with the acid shows that amine forms 1:1complex of ion-pair association with succinic acid, malic acid andmaleic acid, and 1:1, 2:1 complex of ion-pair association withfumaric acid. It is proposed that the complex forms depend on thesecond dissociation constant of the dibasic acid, pK_a2.
基金Supported by the National Natural Science Foundation of China(No.59474009).
文摘The extraction of cadmium and zinc with di-(2-ethylhexyl)-dithiophosphoric acid(D2EHDTPA)-toluene and D2EHDTPA-trioctyl amine(TOA)-toluene has been investigated. Infrared spectrum analysis, the nuclear magnetic resonance spectrum(NMR) analysis and conductivity measurements confirm that the probable structures of the extracted complexes are CdA2 and ZnA2. Cadmium can be extracted by D2EHDTPA very easily. Almost all the cadmium can be extracted, but stripping of cadmium from the organic phase is very difficult. When a mixture of D2EHDTPA and TOA is used, selective extraction of cadmium from zinc sulfate solution can be achieved. Cadmium can be easily stripped from the organic phase.
