栲胶模型化合物与四价钒和五价钒络合反应的研究

Study on complex reaction between tannin extracts model compound and tetravalent vanadium and pentavalent vanadium

为了探究栲胶脱硫工艺过程中不同价态的钒离子与栲胶分子的络合,采用等摩尔比法,通过测定邻苯二酚、连苯三酚、没食子酸和单宁4种栲胶模型化合物在碱性缓冲溶液的环境下分别与四价钒离子和五价钒离子的络合吸光度,考察了这2种钒离子络合的差异,结果表明,栲胶模型化合物与五价钒离子的络合能力强于四价钒离子;钒离子不仅可以与单分子内的邻位羟基络合,同时还可与2个配体分子中的2个羟基络合;配体分子苯环上的其它基团对络合反应会产生一定的影响。

In order to explore the complex reaction between different valence states of vanadium ion and tannin molecules in tannin extract desulfurization process,choosing four kinds of typical tannin extracts model compounds as reactants,which are pyrocatechol,pyrogollol,gallic acid and tannin,determine the absorbance of complex reaction between above four compounds and tetravalent vanadium V（Ⅳ） and pentavalent vanadium V（Ⅴ） respectively in alkaline buffer solution with equal mole ratio method.Investigate the differences between those two vanadium ion.The results show that the complex ability of V（Ⅴ） is stronger than that of V（Ⅳ）.Complex reaction not only exists between vanadium ion and its adjacent oxhydryl in single molecular,but also between vanadium ion and two oxhydryls in two ligands.Other perssads on benzene ring have certain effect on complex reaction.