Dividing wall column(DWC)is shown to be energy efficient compared to conventional column sequence for multi components separation,which is used for olefin separation in fluidization methanol to propylene process in th...Dividing wall column(DWC)is shown to be energy efficient compared to conventional column sequence for multi components separation,which is used for olefin separation in fluidization methanol to propylene process in the present work.Detailed design for pilot DWC was performed and five control structures,i.e.composition control(CC),temperature control(TC),composition-temperature control(CC-TC),temperature difference control(TDC),double temperature difference control(DTDC)were proposed to circumvent feed disturbance.Sensitivity analysis and singular value decomposition(SVD)were used as criterion to select the controlled temperature locations in TC,CC-TC,TDC and DTDC control loops.The steady simulation result demonstrates that 25.7% and 30.2% duty can be saved for condenser and reboiler by substituting conventional column sequence with DWC,respectively.As for control structure selection,TC and TDC perform better than other three control schemes with smaller maximum deviation and shorter settling time.展开更多
The inclusion-complex of CD-MCP （β-cyclodextrin （β-CD） including 1-methylcyclopropene （1-MCP）） was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as...The inclusion-complex of CD-MCP （β-cyclodextrin （β-CD） including 1-methylcyclopropene （1-MCP）） was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as the application of Satava-Sestak＇s, Ozawa＇s and Kissinger＇s methods, the mechanism and kinetics of thermal dissociation of this inclusion complex were studied. An additional mass loss is found at 170-180℃. The mechanism of thermal dissociation of CD-MCP is dominated by a one-dimensional random nucleation and subsequent growth process （A2/3）. The activation energy Es and the pre-exponential factor AS for the process are 102.14 kJ/mol and 3.63×10^10s^-1, respectively. This ES value shows that there is no strong chemical intere, ctions between β-CD and 1-MC;P,展开更多
The chemical industry is nowadays predominantly using fossil raw materials,but the alternative use of bio-based resources is investigated to account for the foreseeable scarcity of fossil feedstocks.A main challenge o...The chemical industry is nowadays predominantly using fossil raw materials,but the alternative use of bio-based resources is investigated to account for the foreseeable scarcity of fossil feedstocks.A main challenge of using biobased feedstocks is the complexity of the impurity profile.For an economic production of bio-based chemicals,the use of intensified processes is inevitable and approaches are needed for the various process intensification techniques to identify their applicability to be used for the production of bio-based components.In the presented study,an approach is shown for the reactive distillation(RD) technology to identify the most critical bio-based impurities and their impact on the reactive distillation process.The investigated case-study is the production of n-butyl acrylate from acrylic acid and n-butanol.Among all initially identified impurities,the key impurities,having the biggest impact on the product purity in the reactive distillation process,are found.These impurities are then studied in more detail and an operating window depending on the impurity concentration is identified for the reactive distillation column.Furthermore,an integrated design of upstream and downstream processes is facilitated,as the presented results can be used in the development of the fermentation processes for the production of the bio-based reactants by decreasing the concentration of the critical impurities.展开更多
基金Supported by Open Research Project of State Key Laboratory of Chemical Engineering(Grant No.SKL-Ch E-16B06)
文摘Dividing wall column(DWC)is shown to be energy efficient compared to conventional column sequence for multi components separation,which is used for olefin separation in fluidization methanol to propylene process in the present work.Detailed design for pilot DWC was performed and five control structures,i.e.composition control(CC),temperature control(TC),composition-temperature control(CC-TC),temperature difference control(TDC),double temperature difference control(DTDC)were proposed to circumvent feed disturbance.Sensitivity analysis and singular value decomposition(SVD)were used as criterion to select the controlled temperature locations in TC,CC-TC,TDC and DTDC control loops.The steady simulation result demonstrates that 25.7% and 30.2% duty can be saved for condenser and reboiler by substituting conventional column sequence with DWC,respectively.As for control structure selection,TC and TDC perform better than other three control schemes with smaller maximum deviation and shorter settling time.
文摘The inclusion-complex of CD-MCP （β-cyclodextrin （β-CD） including 1-methylcyclopropene （1-MCP）） was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as the application of Satava-Sestak＇s, Ozawa＇s and Kissinger＇s methods, the mechanism and kinetics of thermal dissociation of this inclusion complex were studied. An additional mass loss is found at 170-180℃. The mechanism of thermal dissociation of CD-MCP is dominated by a one-dimensional random nucleation and subsequent growth process （A2/3）. The activation energy Es and the pre-exponential factor AS for the process are 102.14 kJ/mol and 3.63×10^10s^-1, respectively. This ES value shows that there is no strong chemical intere, ctions between β-CD and 1-MC;P,
基金funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no.241718,Eurobioref
文摘The chemical industry is nowadays predominantly using fossil raw materials,but the alternative use of bio-based resources is investigated to account for the foreseeable scarcity of fossil feedstocks.A main challenge of using biobased feedstocks is the complexity of the impurity profile.For an economic production of bio-based chemicals,the use of intensified processes is inevitable and approaches are needed for the various process intensification techniques to identify their applicability to be used for the production of bio-based components.In the presented study,an approach is shown for the reactive distillation(RD) technology to identify the most critical bio-based impurities and their impact on the reactive distillation process.The investigated case-study is the production of n-butyl acrylate from acrylic acid and n-butanol.Among all initially identified impurities,the key impurities,having the biggest impact on the product purity in the reactive distillation process,are found.These impurities are then studied in more detail and an operating window depending on the impurity concentration is identified for the reactive distillation column.Furthermore,an integrated design of upstream and downstream processes is facilitated,as the presented results can be used in the development of the fermentation processes for the production of the bio-based reactants by decreasing the concentration of the critical impurities.
