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利用电喷雾质谱(ESI-MS)和紫外-可见吸收光谱(UV-Vis)分析,研究了CrCl3·6H2O 浓度为0.1~0.6 mol·L -1的水溶液和[1ChCl:2EG]/CrCl3·6H2O ILs中,Cr(Ⅲ)配合物的存在形式.研究结果表明,在含有CrCl3·6H2O的溶液中,Cr(Ⅲ)与Cl-和 H2O形成[Cr(H2O)nCl6 -n]n-3配合物,其配合物的优势物种受CrCl3·6H2O浓度的影响.水溶液中Cr(Ⅲ)的优势配合物为[Cr(H2O)6]3+与[Cr(H2O)5Cl]2+,并随CrCl3·6H2O浓度增加,水溶液的 UV-Vis吸收光谱峰红移,[Cr(H2O)5Cl]2+的相对含量增加.而[1ChCl:2EG]/CrCl3· 6H2O ILs中的优势配合物为[Cr(H2O)2Cl4]-和[Cr(H2O)3Cl3],且随 CrCl3· 6H2O 浓度增加,溶液的颜色从浅橙红色逐渐变为深绿色,溶液的 UV-Vis 吸收光谱峰蓝移,[Cr (H2O)3Cl3]的相对量增加.说明CrCl3·6H2O的浓度变化,将影响配体Cl-和 H2O与Cr(Ⅲ)配位结合的配位数,从而影响配合物优势物种的相对量.“,”The existing forms of Cr(Ⅲ)complexes in aqueous solution and[1ChCl:2EG]/CrCl3·6H2O ILs containing 0.1~0.6 mol· L -1CrCl3· 6H2O,respectively,were investigated by using ESI-MS and UV-Vis absorption spectra.The results showed that Cr(Ⅲ)combined with Cl-and H2O to form[Cr(H2O)nCl6 -n]n-3in both cases,and the dominant species of which were affected by the concentration of CrCl3·6H2O.Concretely,the dominant complexes of Cr(Ⅲ)in aqueous solution are[Cr (H2O)6]3+and[Cr(H2O)5Cl]2+,and the UV-Vis absorption spectra is observed to redshift with an increase in the concentra-tion of CrCl3·6H2O,along with enhancement in the mole fraction of[Cr(H2O)5Cl]2+.By contrast,the dominant species of Cr (Ⅲ)in[1ChCl:2EG]/CrCl3·6H2O ILs are[Cr(H2O)2Cl4]-and[Cr(H2O)3Cl3].Increasing the concentration of CrCl3· 6H2O results in gradual color change of the solution from light orange-red to dark green,blue shift of the UV-Vis absorption spectra,and higher mole fraction of[Cr(H2O)3Cl3].Both the coordination number of Cl -and H2O that complexes with Cr(Ⅲ) as well as the relative content of the dominant complexes of Cr(Ⅲ)in solvent is proved to be influenced by variation in the con-centration of CrCl3·6H2O.