Biomass derived heterogenous catalyst for synthesis of solketal from biodiesel byproduct glycerol

Abstract

Glycerol valorisation is crucial for long-term economic viability due to the rise in biodiesel synthesis on a global scale. Therefore, it is highly desirable to convert bioglycerol into platform chemicals like solketal, a fuel additive which will help sustain the biodiesel industry. Herein, glycerol is transformed into solketal utilising a heterogeneous catalyst derived from SO3H-functionalized derived aromatic carbonaceous material with auxiliary hydrophilic groups and microwave irradiation. An ideal glycerol to acetone molar ratio of 1:5 was found for the acetalization process that produces solketal. A conversion of glycerol 98.1.4% with 100% selectivity to solketal was obtained using an 8 wt% catalyst dose at 70 °C for just 10 min using the method of microwave heating (50 W, 100 pressure). The acetalization reaction's activation energy was found to be 35.8 kJ mol−1. The reusability of the catalyst was studied exhaustively over the course of six cycles, and EDX results revealed that there was only a minor loss of activity in the 6th reaction cycle due to moderate leaching of active sites.