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dc.contributor.authorConsoli, Daniel Francis.en_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Chemical Engineering.en_US
dc.date.accessioned2021-10-15T15:23:31Z
dc.date.available2021-10-15T15:23:31Z
dc.date.copyright2019en_US
dc.date.issued2019en_US
dc.identifier.urihttps://hdl.handle.net/1721.1/132981
dc.descriptionThesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, June, 2019en_US
dc.descriptionCataloged from PDF version of thesis. "Due to the condition of the original material, there are unavoidable flaws in this reproduction. We have made every effort possible to provide you with the best copy available"--Disclaimer page.en_US
dc.descriptionIncludes bibliographical references.en_US
dc.description.abstractOlefin metathesis offers a promising technology for on-purpose production of propylene and has been implemented in several industrial processes including the Lummus Olefin Conversion Technology. However, current metathesis technology cannot produce propylene cheaply and efficiently due to reliance on decades-old catalyst technology like tungsten oxide on silica. This poor performance can be attributed to a lack of understanding of heterogeneous metathesis reaction mechanisms and the catalysts involved. Current understanding proposes that olefin metathesis follows the Chauvin mechanism in which olefins coordinate with catalytic metal carbenes to form metallacyclobutanes that then rearrange into metathesis products. While this mechanism has been proven for homogenous metathesis catalysts, for which the 2005 Nobel Prize was awarded, the mechanism over heterogeneous catalysts may be more complicated as metal carbenes do not necessarily exist over freshly prepared material. In this thesis, we present a complete mechanistic cycle for heterogeneous olefin metathesis that comprises carbene site formation, stable metathesis, and active site decay. We demonstrate why this expanded mechanism is necessary to explain reaction order behavior for propylene on WO₃/SiO₂ and the presence of site formation byproducts during isobutene self-metathesis. Furthermore, we leverage our knowledge of the complete mechanism to introduce a secondary olefin to promote active site formation and, consequently, overall metathesis rate. Finally, we utilize our understanding of the importance of site formation to synthesize catalysts supported on tunable zeolite and metal organic framework materials that optimize metal-support interaction and metathesis rates. In sum, an improved understanding of the heterogeneous olefin metathesis mechanism has led to improvements in catalytic design, material characterization, and reactor operation.en_US
dc.description.statementofresponsibilityby Daniel Francis Consoli.en_US
dc.format.extent186 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsMIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectChemical Engineering.en_US
dc.titleMechanisms and catalyst design for heterogeneous Olefin metathesisen_US
dc.typeThesisen_US
dc.description.degreePh. D.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Chemical Engineeringen_US
dc.identifier.oclc1263575086en_US
dc.description.collectionPh.D. Massachusetts Institute of Technology, Department of Chemical Engineeringen_US
dspace.imported2021-10-15T15:23:31Zen_US
mit.thesis.degreeDoctoralen_US
mit.thesis.departmentChemEngen_US


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