Kinetic study of C4 polyol hydrogenolysis on Rh promoted catalyst

EMANUEL VIRGILIO; CRISTINA L. PADRÓ; MARIA EUGENIA SAD

San Diego

Congreso; 17th International Congress on Catalysis; 2020

The International Association of Catalysis Societies and North American Catalysis Society

Erythritol (ERY, C4H10O4) is a promising intermediate produced by fermentation ofsugars that can be obtained from non-edible biomass derives. By C-O hydrogenolysis, valuablebutanediols (BDOs) can be obtained but their consecutive C-O hydrogenolysis producesbutanols and butane, while C-C cleavage leads to lower carbon products (C2-C3), which areless valuable compounds and therefore should be avoided. Butanediols, have manyapplications such as food flavorings, inks, perfumes, fumigants and production of resins.Polyol hydrogenolysis has been previously studied, particularly using glycerol as reactants inaqueous solution to produce 1,2-propanediol and 1,3-propanediol [1]. Typically, noblemetal/support catalysts are used for hydrogenolysis reactions. Pt, Ru, Rh, and Ir have beeninvestigated but Pt was less active, while Ru, often promotes excessive C–C cleavage. Toprevent the break of the carbon chain, an oxophilic promoter (Re, Mo or W) is added to thenoble metal resulting in an improvement of the selectivity to the C-O hydrogenolysis [2].Rh/ReOx bimetallic catalysts supported on TiO2 or ZrO2 were studied to promote the ERYhydrogenolysis to BDOs and the highest selectivity obtained to butanetriol and butanediol was37% and 29% respectively, at 80% ERY conversion (200°C, 120 bar H2) when using3.7wt%Rh-3.5wt.%ReOx/ZrO2 [3]. The effect H2 partial pressure on ERY initial rate waspreviously discussed while the effect of ERY initial concentration and kinetic studies for BDOformation from ERY is still lacking. Therefore, in this work we focused on the C-Ohydrogenolysis of ERY using Rh/ReOx/TiO2 with ̴ 1.8wt% metal contents and 15-35 bar ofhydrogen in order to selectively produce BDO. Also, we compared the catalytic behavior ofmono and bimetallic catalysts and estimated the reaction orders for ERY and H2 as well asactivation energy from kinetic experiments.