| Summary: |
The main objective of this project is the development of a novel hybrid reactive separation process for acetals production. The technology will combine a pervaporation membrane reactor (PVMR) with adsorption in a single unit in order to achieve high acetal purity with complete reactants conversion.
The acetals are oxygenated compounds produced by the reversible reaction between an alcohol and an aldehyde in acid medium. In order to obtain acceptable acetal yields, the equilibrium must be displaced in the direction of acetal synthesis. Commercially, several technologies are used in the production of acetals to displace equilibrium towards acetal formation. At the present, the process of acetals production (diethylacetal, dimethylacetal or others) consists on a reaction followed by separation, usually consecutive energy intense distillations to separate the mixture. In reactions limited by chemical equilibrium where more than one product is formed, conversion can be enhanced in multifunctional reactor where the products are separated as they are formed. Novel reactor configurations and choice of operating conditions can be used to maximise the conversion of reactants and improve selectivity of desired product, thereby reducing the costs associated with the separation step.
The principal investigator of this project has patented a process for acetals production in a Simulated Moving Bed Chromatographic Reactor (PT 103123). In this process, an acid ion exchange resin was used (Amberlyst 15) both as catalyst and as selective adsorbent. The alcohol, that is one of the reactants, also plays the role of desorbent for regeneration of the resin that preferential adsorbs water (by-product of the reaction). In this way, it is necessary to separate the excess of alcohol used and recycle it to the process. The development of a new process based on hybrid technologies of reaction and separation, which combines a PVMR with adsorption, will eliminate that problem. The prop  |
Summary
The main objective of this project is the development of a novel hybrid reactive separation process for acetals production. The technology will combine a pervaporation membrane reactor (PVMR) with adsorption in a single unit in order to achieve high acetal purity with complete reactants conversion.
The acetals are oxygenated compounds produced by the reversible reaction between an alcohol and an aldehyde in acid medium. In order to obtain acceptable acetal yields, the equilibrium must be displaced in the direction of acetal synthesis. Commercially, several technologies are used in the production of acetals to displace equilibrium towards acetal formation. At the present, the process of acetals production (diethylacetal, dimethylacetal or others) consists on a reaction followed by separation, usually consecutive energy intense distillations to separate the mixture. In reactions limited by chemical equilibrium where more than one product is formed, conversion can be enhanced in multifunctional reactor where the products are separated as they are formed. Novel reactor configurations and choice of operating conditions can be used to maximise the conversion of reactants and improve selectivity of desired product, thereby reducing the costs associated with the separation step.
The principal investigator of this project has patented a process for acetals production in a Simulated Moving Bed Chromatographic Reactor (PT 103123). In this process, an acid ion exchange resin was used (Amberlyst 15) both as catalyst and as selective adsorbent. The alcohol, that is one of the reactants, also plays the role of desorbent for regeneration of the resin that preferential adsorbs water (by-product of the reaction). In this way, it is necessary to separate the excess of alcohol used and recycle it to the process. The development of a new process based on hybrid technologies of reaction and separation, which combines a PVMR with adsorption, will eliminate that problem. The proper integration of the two processes will allow the production of acetal with high purity and the complete conversion of the reactants, because water is removed from the reaction mixture.
This project concerns: (a) selection of suitable commercial membrane based on the physical-chemical membrane properties and on performance tests (flux, selectivity etc.) of membranes in pervaporation processes; (b) modelling and simulation of the PVMR with an adsorbent system in order to determine the best operating conditions such as temperature, pressure, membrane thickness, ratio between catalyst and membrane area, and configuration of the reactor; (c) design and construction of pilot plant for acetals production in PVMR and its operation; (d) comparative study of technical-economic viability between the Simulated Moving Bed Reactor and PVMR for diethylacetal production at industrial scale. |