Abstract
H-ZSM-5-based catalyst is a recognized catalyst which is particularly selective towards the formations of light olefins in the methanol reaction. A series of H-ZSM-5 (SiO2/Al2O3 = 38) modified with different amounts of magnesium have been investigated. All the samples were characterized by X-ray diffraction instrument (XRD), temperature-programmed desorption of NH3 (NH3-TPD) and Fourier Transform Infrared Spectoscopy (FT-IR). The results indicated that the impregnation of H-ZSM-5 (SiO2/Al2O3 = 38) zeolite with various magnesium loading amount significantly affected the strength of acid sites and decreased the concentration of both weak and strong acid sites. As a result of modification, magnesium mainly interacted with strong Bronsted acid sites, thus generated new medium strong acid sites and enhanced the yield of propylene. The optimum acid property for methanol to propylene (MTP) reaction was gotten over 4.0 Mg-ZSM-5 (4.0 wt% Mg) zeolite catalyst. The maximum yield of propylene was 10.62 wt% over 4.0 Mg-ZSM-5 zeolite catalyst by the 30 min on stream. Coke which was mostly formed on strong Bronsted acid sites, would cause the catalysts deactivation, so the reduction of strong Bronsted acid sites could enhance the catalytic stability.
Highlights
Propylene is one of the most important organic raw materials for the synthesis of a variety of important downstream chemical materials, such as polypropylene, acrylonitrile, epoxy propane, etc
The results indicated that the impregnation of H-ZSM5 (SiO2/Al2O3 = 38) zeolite with various magnesium loading amount significantly affected the strength of acid sites and decreased the concentration of both weak and strong acid sites
In order to explore the role of acid character in methanol to propylene (MTP) reaction and to enhance propylene selectivity, we imported Mg onto H-ZSM-5(SiO2/Al2O3 = 38) to adjust the acid property and find optimum acidity for MTP reaction
Summary
Propylene is one of the most important organic raw materials for the synthesis of a variety of important downstream chemical materials, such as polypropylene, acrylonitrile, epoxy propane, etc. The results indicated that the impregnation of H-ZSM5 (SiO2/Al2O3 = 38) zeolite with various magnesium loading amount significantly affected the strength of acid sites and decreased the concentration of both weak and strong acid sites. The optimum acid property for methanol to propylene (MTP) reaction was gotten over 4.0 Mg-ZSM-5 (4.0 wt% Mg) zeolite catalyst.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.