Process for the preparation of a 1,2-alkylene diol and a dialkylcarbonate

A process for the preparation of a 1,2-alkylene diol and a dialkylcarbonate, comprising:

• (i) contacting a 1,2-alkylene oxide with carbon dioxide in the presence of a carbonation catalyst in a downflow jet reactor to obtain a reaction mixture containing a 1,2-alkylene carbonate,
• wherein the downflow jet reactor is a reactor comprising a reactor vessel, an ejector means suitable for mixing the gas and the liquid and ejecting the gas/liquid mixture obtained into the reactor vessel, and an outlet means, wherein the ejector means is situated in the upper part of the reactor vessel and the outlet means is situated in the lower part of the reactor vessel, which reactor is operated in a downflow fashion, and
• wherein the downflow jet reactor further comprises a deflection means situated in between the ejector means and the outlet means in the direction of the flow path of the gas/liquid mixture generated by the ejector means;
• (ii) contacting at least part of the reaction mixture obtained in step (i) with an alkanol to obtain a reaction mixture containing a 1,2-alkylene diol and a dialkylcarbonate;
• and
• (iii) recovering the 1,2-alkylene diol and the dialkylcarbonate from the reaction mixture obtained in step (ii).