Valorisation of glycerol through catalytic hydrogenolysis routes for sustainable production of value-added C3 chemicals: current and future trends

The search for sustainable routes for the production of C3 chemicals by using renewable feedstocks has attracted significant interest from academic and industrial communities to alleviate the shortage of fossil fuels. Glycerol, a by-product of biodiesel production, is an attractive and inexpensive renewable feedstock for chemical production through steam reforming, hydrogenolysis, dehydration, and carboxylation. Glycerol is also classified as one of the top 12 building block chemicals and has consolidated its position in the world energy matrix due to its continuous growth in the market. However, less effort has been dedicated to assessing the performance and commercial feasibility of the catalytic routes, notably, the hydrogenolysis for the manufacture of high-value products from glycerol. In this review, we focus on (i) the global market of chemical production from glycerol such as 1,2-propanediol and 1,3-propanediol, (ii) recent literature on the catalysts, reaction conditions, and proposed mechanism of hydrogenolysis of glycerol, (iii) new trends in the catalytic hydrogenolysis of glycerol, and (iv) the expected challenges associated with the scale-up and future outlook of their implications for commercial production.