Unraveling the Homologation Reaction Sequence of the Zeolite‐Catalyzed Ethanol‐to‐Hydrocarbons Process. (14th February 2019)

• Record Type: Journal Article
• Authors: Chowdhury, Abhishek Dutta; Lucini Paioni, Alessandra; Whiting, Gareth T.; Fu, Donglong; Baldus, Marc; Weckhuysen, Bert M.
• Is Part Of: Angewandte Chemie. Volume 131:Number 12(2019)
• Page Start: 3948
• Page End: 3952
• Publication Date: 2019-02-14
• Subjects: Ethanol -- Heterogene Katalyse -- Operando-Techniken -- Spektroskopie -- Zeolithe; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201814268
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Although industrialized, the mechanism for catalytic upgrading of bioethanol over solid‐acid catalysts (that is, the ethanol‐to‐hydrocarbons (ETH) reaction) has not yet been fully resolved. Moreover, mechanistic understanding of the ETH reaction relies heavily on its well‐known "sister‐reaction" the methanol‐to‐hydrocarbons (MTH) process. However, the MTH process possesses a C1 ‐entity reactant and cannot, therefore, shed any light on the homologation reaction sequence. The reaction and deactivation mechanism of the zeolite H‐ZSM‐5‐catalyzed ETH process was elucidated using a combination of complementary solid‐state NMR and operando UV/Vis diffuse reflectance spectroscopy, coupled with on‐line mass spectrometry. This approach establishes the existence of a homologation reaction sequence through analysis of the pattern of the identified reactive and deactivated species. Furthermore, and in contrast to the MTH process, the deficiency of any olefinic‐hydrocarbon pool species (that is, the olefin cycle) during the ETH process is also noted. Abstract : Homologation ist der Schlüssel beim zeolithkatalysierten Ethanol‐zu‐Kohlenwasserstoff‐Prozess. Eine Kombination aus Festkörper‐NMR‐Spektroskopie und Operando‐UV/Vis‐Reflexionsspektroskopie gekoppelt mit Online‐Massenspektrometrie zeigt, dass die von einer Homologationsreaktion dominierte C‐C‐Kupplung für die Bildung von Olefinen und höheren Homologen verantwortlich ist.