{"id":4841,"date":"2017-09-21T21:28:36","date_gmt":"2017-09-22T01:28:36","guid":{"rendered":"http:\/\/catalysisclubphilly.org\/?p=4841"},"modified":"2017-09-21T21:28:36","modified_gmt":"2017-09-22T01:28:36","slug":"olefin-metathesis-supported-mooxal2o3-catalysts","status":"publish","type":"post","link":"https:\/\/catalysisclubphilly.org\/awe9a91v\/abstracts\/olefin-metathesis-supported-mooxal2o3-catalysts\/","title":{"rendered":"Olefin Metathesis by Supported MoOx<\/sub>\/Al2<\/sub>O3<\/sub> Catalysts"},"content":{"rendered":"

Meeting Program \u2014 October 2017<\/h3>\n

Anisha Chakrabar\u00adti<\/strong> \u2014 Stu\u00addent Speak\u00ader<\/p>\n

\nAdvi\u00adsor: Israel E. Wachs
\nOperan\u00addo Mol\u00ade\u00adc\u00adu\u00adlar Spec\u00adtroscopy &<\/span> Catal\u00ady\u00adsis Lab\u00ado\u00adra\u00adto\u00adry
\nDepart\u00adment of Chem\u00adi\u00adcal and Bio\u00admol\u00ade\u00adc\u00adu\u00adlar Engi\u00adneer\u00ading
\nLehigh Uni\u00adver\u00adsi\u00adty, Beth\u00adle\u00adhem, PA 18015 USA<\/em>\n<\/div>\n
\n  \n<\/div>\n

Abstract<\/strong> \u2014 The olefin metathe\u00adsis reac\u00adtion was com\u00admer\u00adcial\u00adized in the late 1960s to pro\u00adduce eth\u00adyl\u00adene and 2-butene from propy\u00adlene in the Phillips Tri\u00adolefin Process. The reverse reac\u00adtion, how\u00adev\u00ader, is cur\u00adrent\u00adly desired due to a glob\u00adal propy\u00adlene short\u00adage caused by the shift to lighter feed\u00adstocks derived from shale gas frack\u00ading. Het\u00adero\u00adge\u00adneous sup\u00adport\u00aded MoOx<\/sub>\/Al2<\/sub>O3<\/sub> cat\u00ada\u00adlysts are employed for olefin metathe\u00adsis in the Shell High\u00ader Olefin Process (SHOP) that oper\u00adates between room tem\u00adper\u00ada\u00adture and ~200\u00b0C.<\/p>\n

To probe the mol\u00ade\u00adc\u00adu\u00adlar details of the sup\u00adport\u00aded MoOx<\/sub>\/Al2<\/sub>O3<\/sub> cat\u00ada\u00adlysts, a mod\u00adern in situ spec\u00adtroscopy approach was under\u00adtak\u00aden. In situ UV-vis mea\u00adsure\u00adments (Eg val\u00adues) con\u00adfirmed the pres\u00adence of iso\u00adlat\u00aded and oligomer\u00adic MoOx<\/sub> sur\u00adface sites, with the lat\u00adter increas\u00ading with molyb\u00adde\u00adna load\u00ading. In situ Raman spec\u00adtroscopy revealed that at low load\u00adings of molyb\u00adde\u00adna (1 Mo atoms\/nm2<\/sup>), only iso\u00adlat\u00aded dioxo (O=)2<\/sub>MoO2<\/sub> sur\u00adface sites are present. As the molyb\u00adde\u00adna load\u00ading is increased (1\u20134.6 Mo atoms\/nm2<\/sup>), oligomer\u00adic mono-oxo O=MoO4<\/sub> sur\u00adface sites co-exist with the iso\u00adlat\u00aded dioxo (O=)2<\/sub>MoO2<\/sub> sur\u00adface sites. Above mono\u00adlay\u00ader load\u00adings (>4.6 Mo atoms\/nm2<\/sup>), crys\u00adtalline MoO3<\/sub> nanopar\u00adti\u00adcles are also present. In situ IR indi\u00adcates that the iso\u00adlat\u00aded dioxo MoO4<\/sub> sites are anchored at more basic HO-\u03bc1<\/sub>-AlIV<\/sub> sur\u00adface hydrox\u00adyls, while the sur\u00adface oligomer\u00adic mono-oxo sites are anchored to more acidic HO-\u03bc1\/3<\/sub>-AlV\/VI<\/sub> sur\u00adface hydrox\u00adyls. Propy\u00adlene metathe\u00adsis at reac\u00adtion con\u00addi\u00adtions sug\u00adgest that the iso\u00adlat\u00aded dioxo (O=)2<\/sub>MoO2<\/sub> sur\u00adface site may still be present after acti\u00adva\u00adtion of the mono-oxo sur\u00adface sites with propy\u00adlene. In situ UV-vis dur\u00ading propy\u00adlene metathe\u00adsis indi\u00adcates that Mo+6<\/sup> sites are dom\u00adi\u00adnant dur\u00ading propy\u00adlene metathe\u00adsis due to the pres\u00adence of unre\u00adduced sur\u00adface dioxo Mo+6<\/sup>O4<\/sub> sites and re-oxi\u00adda\u00adtion of reduced Mo+4<\/sup> sites by propy\u00adlene back to Mo+6<\/sup>=CH2<\/sub> and Mo+6<\/sup>=CHCH3<\/sub> reac\u00adtion inter\u00adme\u00addi\u00adates. The sur\u00adface chem\u00adistry was chem\u00adi\u00adcal\u00adly probed by C3<\/sub>H6<\/sub>-TPSR that ini\u00adtial\u00adly formed oxy\u00adgenat\u00aded prod\u00aducts (CH3<\/sub>CHO, H2<\/sub>CO, CH3<\/sub>COCH3<\/sub>, H2<\/sub>O and CO\/CO2<\/sub>) dur\u00ading cat\u00ada\u00adlyst acti\u00adva\u00adtion. The reac\u00adtiv\u00adi\u00adty of the acti\u00advat\u00aded cat\u00ada\u00adlysts to butene pro\u00adgres\u00adsive\u00adly increased with molyb\u00adde\u00adna load\u00ading, indi\u00adcat\u00ading that the oligomer\u00adic mono-oxo MoOx<\/sub> sites are much more active than iso\u00adlat\u00aded dioxo MoO4<\/sub> sites for olefin metathe\u00adsis. The crys\u00adtalline MoO3<\/sub> nanopar\u00adti\u00adcles, how\u00adev\u00ader, were found to be inac\u00adtive for metathe\u00adsis. This pre\u00adsen\u00adta\u00adtion will address the fun\u00adda\u00admen\u00adtal mol\u00ade\u00adc\u00adu\u00adlar and struc\u00adtur\u00adal details of the sup\u00adport\u00aded MoOx<\/sub>\/Al2<\/sub>O3<\/sub> cat\u00ada\u00adlysts dur\u00ading propy\u00adlene metathe\u00adsis and estab\u00adlish their struc\u00adture-activ\u00adi\u00adty rela\u00adtion\u00adships.<\/p>\n","protected":false},"excerpt":{"rendered":"

Meet\u00ading Pro\u00adgram \u2014 Octo\u00adber 2017 Anisha Chakrabar\u00adti \u2014 Stu\u00addent Speak\u00ader Advi\u00adsor: Israel E. Wachs Operan\u00addo Mol\u00ade\u00adc\u00adu\u00adlar Spec\u00adtroscopy &<\/span> Catal\u00ady\u00adsis Lab\u00ado\u00adra\u00adto\u00adry Depart\u00adment of Chem\u00adi\u00adcal and Bio\u00admol\u00ade\u00adc\u00adu\u00adlar Engi\u00adneer\u00ading Lehigh Uni\u00adver\u00adsi\u00adty, Beth\u00adle\u00adhem, PA 18015 USA   Abstract \u2014 The olefin metathe\u00adsis reac\u00adtion was com\u00admer\u00adcial\u00adized in the late 1960s to pro\u00adduce eth\u00adyl\u00adene and 2-butene from propy\u00adlene in the Phillips [\u2026]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[15,8],"tags":[],"class_list":["post-4841","post","type-post","status-publish","format-standard","hentry","category-abstracts","category-news"],"_links":{"self":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4841","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/comments?post=4841"}],"version-history":[{"count":12,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4841\/revisions"}],"predecessor-version":[{"id":4853,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4841\/revisions\/4853"}],"wp:attachment":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/media?parent=4841"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/categories?post=4841"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/tags?post=4841"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}