The microstructures of loaded organic phases of three quaternary amine solvent extraction systems for gold,which were N263-xylene,N263-tributyl phosphate(TBP)-dodecane and N263-2 -ethylhexanol (isooctanol)-dodecane(N2...The microstructures of loaded organic phases of three quaternary amine solvent extraction systems for gold,which were N263-xylene,N263-tributyl phosphate(TBP)-dodecane and N263-2 -ethylhexanol (isooctanol)-dodecane(N263-trialkylmethylammonium chloride;alkyl=C8-C10),were studied by Fourier transform infrared (FTIR) spectroscopy and extended X-ray abso\rption fine structure(EXAFS) spectroscopy. According to the EXAFS results,it was found that the gold coordination environment was the same before and after extraction.However,the C≡N stretching vibrations of Au(CN)2-were also found to be different,In order to explain the differences in the IR characteristics of C≡N in the three extraction systems,three microstructure models are proposed.For the N263-xylene system,the model is a simple ion pair.For the other two systems with a modifier(TBP and isooctanol),the models are two supramolecular structues based on hydrogen bonding between the modifier and Au(CN)2^-.Some related work such as on the hydration of acetonitrile and the fine structure of C≡N in solid K Au(CN)2 was also performed in order to offer additional supporting evidence for the reliability of the proposed models.展开更多
文摘The microstructures of loaded organic phases of three quaternary amine solvent extraction systems for gold,which were N263-xylene,N263-tributyl phosphate(TBP)-dodecane and N263-2 -ethylhexanol (isooctanol)-dodecane(N263-trialkylmethylammonium chloride;alkyl=C8-C10),were studied by Fourier transform infrared (FTIR) spectroscopy and extended X-ray abso\rption fine structure(EXAFS) spectroscopy. According to the EXAFS results,it was found that the gold coordination environment was the same before and after extraction.However,the C≡N stretching vibrations of Au(CN)2-were also found to be different,In order to explain the differences in the IR characteristics of C≡N in the three extraction systems,three microstructure models are proposed.For the N263-xylene system,the model is a simple ion pair.For the other two systems with a modifier(TBP and isooctanol),the models are two supramolecular structues based on hydrogen bonding between the modifier and Au(CN)2^-.Some related work such as on the hydration of acetonitrile and the fine structure of C≡N in solid K Au(CN)2 was also performed in order to offer additional supporting evidence for the reliability of the proposed models.
