Hydrogen production from aqueous‐phase reforming of glycerol, sorbitol, and glycine over Pt/Al 2 O 3 catalyst in a fixed‐bed reactor

• Published in: International journal of chemical kinetics 2024-07
• Main Authors: Kalekar, Vinayak N., Vaidya, Prakash D.
• Format: Article
• Language: English
• ISSN: 0538-8066; 1097-4601
• DOI: 10.1002/kin.21752

Aqueous‐phase reforming (APR) is an interesting technique for generating hydrogen (H 2 ) from biofeeds. In this work, APR of model compounds of wet biomass for H 2 production was investigated. Glycerol, sorbitol, and glycine were the chosen model compounds. They represent polyols and amino acids in wet biomass such as waste sludge and microalgal biomass. The Pt/Al 2 O 3 catalyst was preferred and it was characterized using nitrogen adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), x‐ray diffraction (XRD), and x‐ray photoelectron spectroscopy (XPS) techniques. APR trials were performed in a continuous fixed‐bed reactor. The reaction conditions chosen for this work were: temperature ( T ) 453–498 K, pressure ( P ) 1.2–2.4 MPa, feed concentration 5–15 wt%, and weight hourly space velocity (WHSV) 0.15–0.6 g reactant/(g catalyst h). The best conditions for H 2 production by the APR process were found to be T  = 498 K, P  = 2.4 MPa, and feed concentration = 15 wt%. Among the chosen model compounds, glycerol exhibited the highest H 2 selectivity (82.7%) and H 2 yield (21.6%) at 498 K. The analysis of kinetic data suggested first‐order reaction kinetics for all the model compounds. The values of activation energy for the reactions with glycerol (55.4 kJ/mol), sorbitol (51.6 kJ/mol), and glycine (45.7 kJ/mol) were determined. Thus, APR is a promising route for effectively producing H 2 ‐bearing gaseous products with high heating value from wet biomass.