Silicon-rich H-ZSM-5 catalyzed conversion of aqueous ethanol to ethylene

• Published in: Journal of catalysis Vol. 117; no. 1; pp. 19 - 32
• Main Authors: Moser, William R., Thompson, Robert W., Chiang, Chen-Chou, Tong, Hao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.05.1989; Elsevier
• Subjects: 10 SYNTHETIC FUELS; 100200 - Synthetic Fuels- Production- (1990-); ALCOHOLS; ALKENES; ALUMINIUM; CATALYSIS; CATALYTIC EFFECTS; CATALYTIC REFORMING; CHEMICAL REACTION KINETICS; CHEMICAL REACTIONS; Chemistry; ELEMENTS; ENRICHMENT; ETHANOL; ETHYLENE; Exact sciences and technology; General and physical chemistry; HYDROCARBONS; HYDROXY COMPOUNDS; INORGANIC ION EXCHANGERS; ION EXCHANGE MATERIALS; KINETICS; MATERIALS; METALS; MINERALS; ORGANIC COMPOUNDS; QUANTITY RATIO; REACTION KINETICS; REFORMER PROCESSES; SEMIMETALS; SILICON; SYNTHESIS; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; ZEOLITES; Temperature; Hydrocarbon; Selectivity; Zeolite; Experimental study; Molecular sieve; Primary alcohol; Catalytic conversion; Hydrogen Ions; Aqueous solution; Ion exchange; Catalyst activity; Catalyst; Modified material
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/0021-9517(89)90217-0

A study of the H-ZSM-5 catalysis of the conversion of aqueous ethanol solutions to ethylene was carried out using zeolites having Si/Al atom ratios of 35 to 15,000. Rates of ethanol conversion dropped sharply as expected until a Si/Al ratio of about 500; at higher ratios the activity was maintained at a nearly constant level. All of the synthesized zeolites afforded 100% conversion of 20% aqueous ethanol when examined at 400 °C and space velocities (WHSV) of 3.4 hr −1 (based on the ethanol component). The ethylene selectivities steadily increased with the Si/Al ratio and reached a maximum of 99.6% using the silicon-rich H-ZSM-5 zeolites. The unusually high catalytic activity observed for the silicon-rich materials was attributed to especially reactive clusters of hydrogen-bonded silanols and was shown to be independent of the aluminum concentration.