Li Zheng, Bruynseels Brent, Zhang Zidan, Binnemans Koen
KU Leuven, Department of Chemistry, Celestijnenlaan 200 F, bus 2404, Heverlee B-3001, Belgium.
University of Texas at Austin, Department of Chemical Engineering, Texas 78712, United States.
Ind Eng Chem Res. 2019 Jul 10;58(27):12459-12464. doi: 10.1021/acs.iecr.9b00768. Epub 2019 Jun 21.
Separation of GaCl from other associating chloride compounds (. AlCl, SbCl, and InCl) is generally achieved by hydrometallurgical processes. In this study, we explore the separation of GaCl from these compounds on the basis of the exceptionally high solubility of GaCl in hydrocarbon solvents. We found that GaCl can be efficiently extracted by anhydrous -dodecane from a solid mixture of GaCl and AlCl; on the contrary, SbCl and InCl significantly reduce the extraction of GaCl. On the basis of Lewis acidity theory and study of the Raman spectra, it is shown that formation of the ionic compound [SbCl][GaCl] is responsible for the reduced GaCl extraction. Formation of [InCl][GaCl] is also likely, but further study is needed to support the existence of this compound. Further making use of the strong Lewis acidity of GaCl, GaCl can be efficiently stripped from the loaded -dodecane phase by solid NaCl through formation of NaGaCl. The extraction of GaCl by -dodecane, in combination with its stripping by NaCl, is a solvometallurgical process that is essentially different from the hydrometallurgical processes for the separation of GaCl and AlCl.
从其他缔合氯化物化合物（如AlCl、SbCl和InCl）中分离出GaCl通常通过湿法冶金工艺实现。在本研究中，我们基于GaCl在烃类溶剂中极高的溶解度，探索从这些化合物中分离GaCl的方法。我们发现，无水正十二烷可以从GaCl和AlCl的固体混合物中高效萃取GaCl；相反，SbCl和InCl会显著降低GaCl的萃取率。基于路易斯酸度理论并通过拉曼光谱研究表明，离子化合物[SbCl][GaCl]的形成是GaCl萃取率降低的原因。[InCl][GaCl]的形成也有可能，但需要进一步研究来证实该化合物的存在。进一步利用GaCl的强路易斯酸度，通过形成NaGaCl，固体NaCl可以有效地从负载正十二烷相中反萃GaCl。正十二烷对GaCl的萃取及其被NaCl反萃的过程，是一种溶剂冶金工艺，与用于分离GaCl和AlCl的湿法冶金工艺本质上不同。
