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Organic carbonates have attracted considerable attention because of their numerous applications. The direct association of CO2 and alcohol to synthesise these carbonates is one of the most promising routes, when considering the economic and the environmental aspects. A significant number of researchers have worked on the catalysis and the dehydration of these reactions, but very few have dealt with the study of the thermodynamic equilibrium and the kinetics of these reactions. The objective of this work is to study the synthesis of diethyl carbonate (DEC) and propylene carbonate (PC). A parametric study was conducted by varying the temperature, the pressure and the initial concentration. Equilibrium constants were determined experimentally and compared to available published data. Kinetic models are developed based on four mechanisms, two of which are the mechanisms of Langmuir–Hinshelwood and Eley–Rideal. Mean deviations between the experimental data and the modelling were below 10% for all the mechanisms. The best fit was obtained for the mechanism of Langmuir–Hinshelwood for the synthesis of DEC and PC. Activation energies of 100 kJ/mol and 77 kJ/mol were determined for the synthesis of DEC and PC, respectively.

Capture, storage and valorisation of CO2 are efficient solutions to reduce the emissions of greenhouse gas. To improve these technologies, there is a need to have a good knowledge of the interactions between CO2 and some current solvents. In this article, the solubility of CO2 in methanol, ethanol and 1,2-propanediol is measured by a constant-volume method for temperatures between 283.15 K and 373.15 K and for pressures below 6.0 MPa. The same method is used for glycerol for pressures up to 2.0 MPa. For all of the studied solvents, the solubility increases when temperature decreases and when pressure increases. No literature data was available for this wide range of temperature for ethanol, methanol, 1,2-propanediol and glycerol. Henry’s law constants are calculated for each temperature and are compared between to one another. The solubility of CO2 in these solvents increases in the following order: glycerol

This work is focused on the synthesis of organic carbonates from CO2 and ethanol. A parametric study of the synthesis of diethyl carbonate from ethanol is performed in a 100 mL batch reactor. The influence of pressure and temperature is studied and we prove that the presence of water strongly decreases the yield in diethyl carbonate as an equilibrium is quickly reached. One method to improve this yield is to remove water from the reaction mixture to shift the equilibrium toward the formation of carbonates. The chemical methods give good results but separation and regeneration associated steps are prohibitive. For these reasons, a physical technique like pervaporation is chosen to remove water. The study of a pervaporation cell with membrane PERVAP 4100 gives good results for the dehydration of ethanol alone even at low concentrations of water from 0.33 %wt to 0.15 %wt. Twelve experiments on the dehydration of a mixture of ethanol, diethyl carbonate and water are performed. The calculated separation factors show a very good selectivity for water. That means that even in the presence of diethyl carbonate, the membrane has still a selective water permeability.