Alcohol-water Vapor-liquid Equilibrium Under Reduced Pressure And Property Characterization Of Products By Alkoxide Hydrolysis And Calcination

In this paper, we determine the composition of vapor-liquid by Karl Fischer titration method.Then get vapor-liquid equilibrium phase diagram of ethanol-water system and isopropanol-water the system under the pressure of0.1～1atm. And through the use of UNIFAC group contribution method and area integration method for vapor-liquid equilibrium data were thermodynamic consistency test. Use chemical simulation software ASPEN PLUS conducted under reduced pressure and alcohol-water system VLE data modeling, and compared the results with experimental measurements. Hydrolysis of aluminum isopropoxide was distilled under reduced pressure using dried alumina precursor prepared to study the performance changes precursor calcined at different temperatures, and the thermal decomposition kinetics of the precursor were investigated.The results show that the ethanol under reduced pressure-water, isopropanol-water system of the lowest boiling point are present, the water content of the azeotropic composition is about4%and about13%, both the azeotropic temperature and elevated pressure with increased water content is higher than in the liquid composition after azeotropic composition, the composition of the vapor phase difference becomes larger.Thermodynamic consistency test results area integration method for vapor-liquid equilibrium data showed that under reduced pressure tested, the test results were able to meet the requirements of thermodynamic consistency. Comparison with theoretical calculations you can see the test results with theoretical calculations within the error range of5%of basic correlation coefficient over0.9.Aluminum isopropoxide hydrolyzate is intended boehmite. Boehmitc was proposed transition phase calcined at different temperatures:Proposed boehmiteâ†'γ-Al2O3â†'-Al2O3â†'-Al2O3â†'α-Al2O3. Aluminum hydroxide thermal decomposition process is completed in two phases, the first phase of surface dehydration process, follow the model of the reaction mechanism D3, the activation energy of aluminum hydroxide dehydration process is36.506kJ· mol-1, the pre-exponential factor of85.001the second stage is the internal structure of water removal process, D4is controlled by the two-dimensional diffusion model, the activation energy for the phase transformation206.553kJ· mol-1, the pre-exponential factor of5.843×1012,1.047reaction order...