Catalytic conversion of cellulosic biomass to ethylene glycol: Effects of inorganic impurities in biomass. (January 2015)

• Record Type: Journal Article
• Authors: Pang, Jifeng; Zheng, Mingyuan; Sun, Ruiyan; Song, Lei; Wang, Aiqin; Wang, Xiaodong; Zhang, Tao
• Is Part Of: Bioresource technology. Volume 175(2015)
• Page Start: 424
• Page End: 429
• Publication Date: 2015-01
• Subjects: Lignocellulosic biomass -- Inorganic impurities -- Ethylene glycol -- Tungstenic catalyst -- Deactivation mechanism; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2014.10.076
• Languages: English
• ISSNs: 0960-8524

Abstract

Abstract : Graphical abstract: The effects of inorganic impurities in biomass on the catalytic conversion of cellulose to ethylene glycol (EG) were investigated, and the mechanisms of catalyst deactivation by certain impurities were identified. The impurities in biomass were selectively removed, using suitable pretreatments, and the EG yield reached 50%, even for conversion of an industrial cellulosic feedstock at a high concentration of 10%. Highlights: Effects of 16 impurities on conversion of cellulose to EG were investigated. Some ions changed the solution pH and therefore decreased EG yields. Ca and Fe ions decreased EG yield by reacting with W ion to form insoluble compounds. The pH and the W ion concentration should be 5–6 and >187 ppm for high EG yields. After removal of lignin and most harmful ions, EG yields could reach 50%. Abstract: The effects of typical inorganic impurities on the catalytic conversion of cellulose to ethylene glycol (EG) were investigated, and the mechanism of catalyst deactivation by certain impurities were clarified. It was found that most impurities did not affect the EG yield, but some non-neutral impurities or Ca and Fe ions greatly decreased the EG yield. Conditional experiments and catalyst characterization showed that some impurities changed the pH of the reaction solution and affected the cellulose hydrolysis rate; Ca and Fe cations reacted with tungstate ions and suppressed the retro-aldol condensation. To obtain a high EG yield, the pH of the reaction solution and the concentration of tungstate ions should be respectively adjusted to 5.0–6.0 and higher than 187 ppm. For raw biomass conversion, negative effects were eliminated by suitable pretreatments, and high EG yields comparable to those from pure cellulose were obtained.