Layered double hydroxides as base catalysts for the synthesis of dimethyl carbonate

In this work, we have prepared two series of layered double hydroxides (LDHs) based on three different divalent cations (Zn2+, Ni2+ and Mg2+), that were ion-exchanged by a trivalent cation (Al3+). The charge was balanced with interlayer anions, either silicate or carbonate. Thus, we have synthetized six different samples and we have studied their physicochemical properties by a wide range of techniques, in order to elucidate their properties. Finally, we have used the prepared materials as catalysts in the transesterification of ethylene carbonate with methanol to produce dimethyl carbonate and ethylene glycol. We have found that materials containing Ni as divalent cation present better catalytic activity due to their basic properties, whereas catalysts containing silicate as interlayer anion yield better selectivity, since they have a lower amount of acid sites.