Dissertation > Excellent graduate degree dissertation topics show

Studies on Oxidative Dehydrogenation of Propane over Cesium Salts of 12-tunstophosphoric Acid and Hydroxylation of Benzene to Phenol over Cu-zeolite Catalysts with Molecular Oxygen in Gas-phase

Author: ZhangJiZhe
Tutor: ZhangQingHong；WanHuiLin
School: Xiamen University
Course: Physical and chemical
Keywords: Cs salt of 12-tunstophosphoric acid Acidity Mesoporous structure Oxidative dehydrogenation Propane Cu-H-ZSM-5 Hydroxylation Benzene Phenol
CLC: O643.3
Type: Master's thesis
Year: 2009
Downloads: 160
Quote: 1
Read: Download Dissertation

Abstract


This dissertation first studied the oxidative dehydrogenation of propane over Cs salts of Keggin-type CsxH3-xPW12O40 which were synthesized by precipitation between dilute aqueous solutions of H3PW12O40 and Cs2CO3.From XRD,IR, N2-adsorption,SEM,H2-TPR and NH3-TPD characterizations,it is clear that along the increase in Cs content of CsxH3-xPW12O40 samples,the concentration of acid site decreased gradually,and the microstructure transformed step by step from compact large particles(for CsxH3-xPW12O40,x＜2.0) to nano-sized spheres with which mesoporous structure was constructed(for CsxH3-xPW12O40,x＞2.2).The relationship between catalytic behaviors and the physicochemical properties of CsxH3-xPW12O40 samples suggests that the acidity and the microstructure played important roles on determining their catalytic performance in ODH of C3H8.Over the CsxH3-xPW12O40 （0.9＜x＜2.0） catalysts without mesoporous structure,the conversion of C3H8 decreased along the abatement in the concentration of acid site,and the selectivity of C3H6 formation was much higher than those over CsxH3-xPW12O40（2.2≤x≤2.7） catalysts.Over the CsxH3-xPW12O40（2.2≤x≤2.7） catalysts with mesoporous structure, the conversion of C3H8 was slightly improved although the concentration of acid site decreased,however most of the target products C3H6 was converted to CO2,probably owing to the strong adsorption effect of mesopores for C3H6.The highest yield of C3H6 was achieved over the Cs1.5H1.5PW12O40 catalyst which possessed concentrated acid site and non-porous structure.This dissertation also studied the hydroxylation of benzene with molecular oxygen in gas-phase over Cu-H-ZSM-5 catalysts which were synthesized by solid state ion exchange method.From XRD,UV-vis and H2-TPR characterizations,it is clear that ion exchange calcination temperature,Cu loading and Si/Al ratio can change the interaction strength between Cu species and support（ZSM-5）,and also the dispersion of Cu species.The state of Cu species determine the catalytic performance in hydroxylation of benzene.The maximum yield of benzene（＞10%） was achieved over the SR1123K-1.5wt%Cu-ZSM-5（25） catalyst.

Related Dissertations

  1. Study on Cosmogonical Myth of Bon,B989.1
  2. Effects of Enzymes on Metabolism of Polycyclic Aromatic Hydrocarbons in Plant,X173
  3. Theeffect of Environmental Factor on Rooting Culture of Paeonia Suffruticosa in Vitro,S685.11
  4. Liquid-liquid Equilibrium for Extraction Separation Benzene and Cycloheane Using N, N-Dimethylformamide and Potassium Thiocyanate,TQ028.3
  5. Synthesis and Application of New Halogen-free Flame Retardant Cotton with Expandable Anti-wrinkle Agent PNX,TQ314.248
  6. The Influence of Antibiotics on Yogurt During the Fermentation,TS252.54
  7. Study on Oxidation Treatment of Phenol Contaminted Soil Using Potassium Ferrate,X53
  8. Preparation of Electrode by Electrodeposition and Study on Performance of Degradation Phenol Wastewater,X703
  9. Concentration and Impact Factors of Typical VOCs in Indoor Air in Hangzhou,X51
  10. Research on Isolation and Polyphasic Taxonomy of a Phenol Tolerant Novel Species-Comamonas Zonglianii BF-3~T,X172
  11. Research phenolic pollutants transition metal / carbon catalytic electrode degradation,X703
  12. Total doped TiO 2 Visible Preparation, Characterization and Properties,O643.36
  13. Study on the Synthesis、Preparation and Properties of Modification Phenolic Resin/NBR Composite Adhesive,TQ433
  14. Preparation and Catalytic Performance of ZrO2-SiO2 Mixed Oxide for THF Polymerization,O631.5
  15. Study on Cytotoxicity, DNA Damage and Repair Induced by Phenol in Vitro,R114
  16. Effects of Phenol on Digestive Function of Moina Macrocopa,X174
  17. Protective Effect of rhPTH on Mice Hematopietic Injury,R551.3
  18. Exploration of Friedel-Crafts Acylation in Ionic Liquids,O643.32
  19. Studying Fragmentation of Aromatic Ligand and Transition-Metal Compounds Using Mass Spectrometry,O641.4
  20. Prepatation of Pr/Al2O3 and Its Activity in Catalytic Ozonation,X703
  21. The Study of Two Phenolic Organic Oxidated by Ozone and the Acute Toxicity,X703

CLC: > Mathematical sciences and chemical > Chemistry > Physical Chemistry ( theoretical chemistry ),chemical physics > Chemical kinetics,catalysis > Catalytic
© 2012 www.DissertationTopic.Net  Mobile