Synthesis,Characterization Of Sulfated Binary Oxide Solid Acid Catalysts And Their Application In Esterification Reactions

Recently, in the study of acid-base catalysis, many chemical reactions could be carried out under very mild conditions by solid superacid catalysts.We can say it is a green catalyst that has a wide prospect of application. However, because its property such as catalytic activity is related with the preparation methods,researchers usually need to improve the preparation methods.At the same times, associating catalytic activity to the results of characterization to gain a better solid superacid.Based on these considerations, the main research as following,Firstly, SO42-/ZrO2-γ-Al2O3 Sulfated binary oxide Solid Superacid Catalysts modified byY3+ was prepared. The experiment indicates that dopingγ-Al2O3 and rare-earth element Y could promote the stabilization of Tetragonal ZrO2 crystalline phase.The existence of the Metastable Tetragonal ZrO2 crystalline phase exhibites high catalytic activity to the Synthesis of dibutyl oxalate from Oxalic acid dihydrate and n-Butanol.Correlation of catalytic activity and ZrO2 crystalline phase is studied. The reutility property of catalyst is fine, but the stabilization also needs further improving.Secondly,SO42-/TiO2-γ-Al2O3 solid superacid catalyst is prepared.The experiment indicates that dopingγ-Al2O3 increased the temperature for transformation of Anatase TiO2 crystalline phase to Rutile TiO2 crystalline phase,The introduction ofγ-Al2O3 delayed the trend of the transition from Anatase TiO2 crystalline phase to Rutile TiO2 crystalline phase. Greatly promote the stabilization of the solid superacid catalyst. Synthesis of Diisopentyl maleate from maleic anhydride and iso-Amyl alcohol by this catalysts is studied. The experiment indicates that this solid acid exhibites high catalytic activity and selectivity. The reutility property and stabilization of catalyst is fine.Thirdly, The Monoclinic type SO42-/TiO2-ZnO Sulfated binary oxide solid acid catalyst is prepared by microwave assisted homogenous precipitation. Through the introduction of microwave, Coming to being the transformation of Anatase TiO2 crystalline phase to Monocline TiO2 crystalline phase and then to Rutile TiO2 crystalline phase. And the synthesis of dibutyl oxalate from Oxalic acid dihydrate and n-Butanol is studied by this catalyst. The experiment indicates that this solid acid exhibites high catalytic activity and selectivity. The reutility property and stabilization of catalyst is fine.Fourthly, Brookite TiO2 with single phase type SO42-/TiO2 solid acid catalyst has been successfully synthesized by hydrothermal method. Influence on the formation of Brookite TiO2 phase is studied by single-factor method. Coming to being the transformation of Anatase TiO2 crystalline phase to Brookite TiO2 crystalline phase and then to Rutile TiO2 crystalline phase. Synthesis of Diisopentyl maleate from maleic anhydride and iso-Amyl alcohol by this catalysts is studied. The experiment indicates that this solid acid exhibites high catalytic activity and selectivity. The reutility property and stabilization of catalyst is fine.Fifthly, Transformation of crystalline phase is characterized by FT-IR,TG-DTA,XRD,Raman and so on. Realizing catalyst crystal microscopic controllable adjustment to obtain solid superacid with higher catalytic activity,selectivity and stabilization.At the same time, carrying on an investigation into correlation of catalytic activity and crystalline phase.