Effect of impurity on thermally self-sustained double reactor coupling hydrogen production from glycerol reforming and methanol production from carbon dioxide and hydrogen

Centre of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand

^* Corresponding author: pattaraporn.k@chula.ac.th

Abstract

Thermally self-sustained double reactor (TSSDR) operating without external heat source consists of dual channels for endothermic and exothermic reactions. Hydrogen (H₂) is produced from wasted glycerol by aqueous-phase glycerol reforming (APGR) at 200-250 ºC and 20-25 bar while carbon dioxide (CO₂) is a by-product. Produced H₂ and CO₂ are used as raw materials for methanol synthesis (MS) at 200-250 ºC and 50-80 bar. Methanol synthesis and glycerol reforming occur at inner and outer channels of TSSDR, respectively. The TSSDR is fully packed with catalyst. Generated heat of exothermic reaction is sufficient for endothermic reaction. Main products of glycerol reforming in gas phase are H₂ and CO₂ while CO and CH₄ are by-products. All products in gas phase are totally recycled as a feed stream for exothermic channel. CO and CH₄ in feed reduce CO₂ conversion and methanol yield in MS. The effect of impurities in glycerol feed stream also influences with hydrogen production in APGR. Especially, methanol, which is an impurity in glycerol feed obtained from biodiesel production, significantly reduces glycerol conversion in TSSDR.