【作者】 陈秋华；

【导师】 卫敏；

【作者基本信息】 北京化工大学 ， 应用化学， 2009， 硕士

【摘要】 本论文采用共沉淀方法将半胱氨酸插层进入镁铝水滑石层间,详细研究了半胱氨酸与铁氰化钾的层间限域氧化还原反应。通过XRD、Raman和FT-IR等表征手段,发现层间半胱氨酸被氧化为胱氨酸。进一步系统研究了该反应的动力学过程,考察了半胱氨酸插层水滑石用量、铁氰化钾浓度和温度对反应的影响。结果表明该氧化还原反应符合球体内扩散反应模型,即Crank-Ginstling and Brounshtein方程。通过计算得到该反应的活化能为29.93 kJ/mol。本论文工作将水滑石作为一种限域化学反应的微反应器,为其在催化和分离方面的应用提供了新的研究思路。采用原位生长技术制备了CuZnAl三元水滑石薄膜,以苯酚羟基化反应为探针反应,分别研究了Cu²⁺/Zn²⁺比例为1:1、2:1、3:1的CuZnAl-LDHs薄膜的催化性能。研究结果表明:与CuZnAl-LDHs粉体催化剂相比,CuZnAl-LDHs薄膜催化剂显示出较高的催化活性和选择性。苯酚的转化率达到75.6%,邻苯酚/对苯酚的选择性达到3.1:1。初步探讨了反应的催化循环机理。因此,本文工作为基于滑石的结构化催化剂在工业上的应用奠定了一定的理论基础。更多还原

【Abstract】 The amino acid L-cysteine（L-Cys） was intercalated into a MgAl layered double hydroxide（LDH）,and its oxidation reaction by hexacyanoferrate（Ⅲ） (Fe（CN）₆^3-) in the confined region between sheets of LDH has been studied in detail.Based on the measurement results of XRD,Raman and FT-IR,it was found that the interlayer L-Cys was oxidized to cystine by Fe（CN）₆^3-. Furthermore,the kinetics of this reaction was investigated in batch mode.The influences of L-Cys-LDH quantity,initial Fe（CN）₆^3- concentration and reaction temperature on the interlayer oxidation reaction have been studied, respectively.The reaction follows a diffusion-controlled mechanism represented by Crank-Ginstling and Brounshtein kinetic model with the apparent activation energy of 29.93 kJ/mol.Cu/Zn/Al layered double hydroxide（LDH） films were fabricated on the aluminum substrates by using an in-situ growth prodecure.The structure and morphology of the LDH films were investigated by XRD,FT-IR,SEM and XPS.The results show that the hexagonal plate-shaped CuZnAl LDH crystallites grow perpendicularly on substrates.The catalytic properties of the CuZnAl-LDHs were studied by using phenol hydroxylation as a probe reaction.It was found that the CuZnAl-LDHs film catalyst exhibits both higher catalytic activity and selectivity for the reaction compared with the powder catalyst sample.Moreover,a catalytic mechanism was proposed to illustrate the superior catalytic proformances of the CuZnAl-LDHs film catalysts.更多还原