Selective hydroxyethylation of furfuryl alcohol with aqueous acetaldehyde in the presence of H-form zeolites

摘要

Hydroxyethylation of furfuryl alcohol with aqueous acetaldehyde was performed at 318 Krnin the presence of FAU, MOR and MFI zeolites in their protonic form. A selectivity of aboutrn55 % in the intermediate carbinol was achieved in the presence of a MFI catalyst with a Si/Alrnratio of 25 for a furfuryl alcohol conversion up to 65 %. Apart from the hydroxyethylatedrnintermediate, two other reaction products, the vinyl derivative and the dimer were also foundrnin the reaction mixture. Moreover, two other reactions may compete, i.e. oligomerisation ofrnacetaldehyde and resinification of furfuryl alcohol. The former reaction is easily controlledrnover the MFI (25) catalyst but the latter is not, and linear furanic polymers, capable ofrndeactivating more or less rapidly the catalyst, were often formed. The selectivity could bernincreased to 95 % by optimisation of the kinetic parameters, but to the detriment of furfurylrnalcohol conversion. Finally, the presence of the vinyl derivative might be a relevantrnheterogeneous alternative route to the conventional Wittig-Horner reaction.