Abstract
Regulating the acid property of zeolite is an effective strategy to improve dehydration of intermediate alcohol, which is the rate-determining step in hydrodeoxygenation of lignin-based phenolic compounds. Herein, a commercial Hβ (SiO2/Al2O3 = 25) was modified by phosphoric acid, and evaluated in the catalytic performance of guaiacol to cyclohexane, combined with Ni/SiO2 prepared by the ammonia evaporation hydrothermal (AEH) method. Incorporating a small amount of phosphorus had little impact on the morphology, texture properties of Hβ, but led to dramatic variations in acid property, including the amount of acid sites and the ratio of Brønsted acid sites to Lewis acid sites, as confirmed by NH3-TPD, Py-IR, FT-IR and 27Al MAS NMR. Phosphorus modification on Hβ could effectively balance competitive adsorption of guaiacol on Lewis acid sites and intermediate alcohol dehydration on Brønsted acid sites, and then enhanced the catalytic performance of guaiacol hydrodeoxygenation to cyclohexane. By comparison, Hβ containing 2 wt.% phosphorus reached the highest activity and cyclohexane selectivity.
Highlights
Introduction and Andrey ChistyakovBio-oil from biomass depolymerization is an ideal substitute for conventional fossil fuels due to the increase of crude oil price and environmental pollution
We found that the selectivity of cyclohexane was closely associated with the acid properties of Hβ zeolite
The physiochemical properties of parent and P-modified Hβ zeolites are shown in Catalysts 2021, 11, 962 on zeolite, phosphorus was reported to sublimate during roasting
Summary
Introduction and Andrey ChistyakovBio-oil from biomass depolymerization is an ideal substitute for conventional fossil fuels due to the increase of crude oil price and environmental pollution. Lercher’s group [7] found that a bifunctional combination of Raney Ni and Nafion/SiO2 could effectively convert bio-derived aromatic monomers into hydrocarbons. In this process, phenolic compound was firstly hydrogenated by Ni species to form intermediate alcohol, and subsequently hydrodeoxygenated to generate cycloalkane by the synergistic effect of Brønsted acid sites and active Ni sites. It was demonstrated that further dehydration of intermediate alcohol over Brønsted acid sites was the rate-determining step in this cascade reaction This group [8] reported that the dehydration rate of intermediate alcohol on HZSM-5 was far greater than that on Nafion/SiO2. The high performance of HZSM-5 zeolite in alcohol dehydration was ascribed to its large adsorption capacity of alcohol, closely related to the crystalline structure, pore size and acid property
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
