{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/17656"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/17656","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"The oligomerization of propene over nickel synthetic mica-montmorillonite","abstract":"The catalytic oligomerization of propene to liquid fuels using synthetic mica montmorillonite (SMM) as well as the effect of incorporating nickel into the lattice and nickel, cobalt and zinc into the interlayer spaces was investigated. NiSMM is more active for propene oligomerization than SMM, although the product selectivity (60% of the oligomers boiled at above 453 K) is similar. The increase in activity of NiSMM is attributed to an increase in the surface acidity of the catalyst. The maximum activity over the nickel exchanged catalyst occurs at a nickel loading of 0.057 wt %. It is proposed that the bond strength of the acidic hydroxyl groups are perturbed by the polarizing effect of the divalent cation (Co, Zn or Ni) present in the interlayer spaces of SMM. The reduction of nickel, ion exchanged into SMM, removes the induction period associated with SMM and increases the catalyst lifetime. However, reduction of the lattice nickel results in a decrease in catalyst lifetime although the Bronsted acidity has increased. It is proposed that the metallic nickel present in reduced NiSMM may promote dehydrogenation of high molecular weight hydrocarbons thus causing rapid deactivation of the catalyst by increasing the formation of \"graphitic\" coke. The lifetime of NiSMM is greatly reduced by using a wet propene feed and reacting at higher temperatures (443 K) due to the generation of Bronsted sites and increased coke formation rates, respectively. Deactivation of the catalyst is associated with a \"graphitic\" coke build up. The RON of the petrol fraction is 94.5 and the hydrogenated diesel fraction has a cetane number less than 35.","abstract_html":"The catalytic oligomerization of propene to liquid fuels using synthetic mica montmorillonite (SMM) as well as the effect of incorporating nickel into the lattice and nickel, cobalt and zinc into the interlayer spaces was investigated. NiSMM is more active for propene oligomerization than SMM, although the product selectivity (60% of the oligomers boiled at above 453 K) is similar. The increase in activity of NiSMM is attributed to an increase in the surface acidity of the catalyst. The maximum activity over the nickel exchanged catalyst occurs at a nickel loading of 0.057 wt %. It is proposed that the bond strength of the acidic hydroxyl groups are perturbed by the polarizing effect of the divalent cation (Co, Zn or Ni) present in the interlayer spaces of SMM. The reduction of nickel, ion exchanged into SMM, removes the induction period associated with SMM and increases the catalyst lifetime. However, reduction of the lattice nickel results in a decrease in catalyst lifetime although the Bronsted acidity has increased. It is proposed that the metallic nickel present in reduced NiSMM may promote dehydrogenation of high molecular weight hydrocarbons thus causing rapid deactivation of the catalyst by increasing the formation of "graphitic" coke. The lifetime of NiSMM is greatly reduced by using a wet propene feed and reacting at higher temperatures (443 K) due to the generation of Bronsted sites and increased coke formation rates, respectively. Deactivation of the catalyst is associated with a "graphitic" coke build up. The RON of the petrol fraction is 94.5 and the hydrogenated diesel fraction has a cetane number less than 35.","abstract_has_math":false,"creators":["Jacobs, Lester Lance"],"institution":"Department of Chemical Engineering","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["O'Connor, Cyril","Kojima, M"],"committee_chairs":[],"committee_members":[],"year":1987,"date_issued":"1987","date_published":"1987","updated_at":"2026-07-22T22:22:54Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/17656","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["O'Connor, Cyril","Kojima, M"]},{"key":"dc:creator","label":"Author","values":["Jacobs, Lester Lance"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-03-11T14:26:44Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-03-11T14:26:44Z"]},{"key":"dc:date.issued","label":"Date","values":["1987"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Chemical Engineering"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Master Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["MSc"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/17656"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Bibliography: pages 150-156."]},{"key":"dc:description.abstract","label":"Abstract","values":["The catalytic oligomerization of propene to liquid fuels using synthetic mica montmorillonite (SMM) as well as the effect of incorporating nickel into the lattice and nickel, cobalt and zinc into the interlayer spaces was investigated. NiSMM is more active for propene oligomerization than SMM, although the product selectivity (60% of the oligomers boiled at above 453 K) is similar. The increase in activity of NiSMM is attributed to an increase in the surface acidity of the catalyst. The maximum activity over the nickel exchanged catalyst occurs at a nickel loading of 0.057 wt %. It is proposed that the bond strength of the acidic hydroxyl groups are perturbed by the polarizing effect of the divalent cation (Co, Zn or Ni) present in the interlayer spaces of SMM. The reduction of nickel, ion exchanged into SMM, removes the induction period associated with SMM and increases the catalyst lifetime. However, reduction of the lattice nickel results in a decrease in catalyst lifetime although the Bronsted acidity has increased. It is proposed that the metallic nickel present in reduced NiSMM may promote dehydrogenation of high molecular weight hydrocarbons thus causing rapid deactivation of the catalyst by increasing the formation of \"graphitic\" coke. The lifetime of NiSMM is greatly reduced by using a wet propene feed and reacting at higher temperatures (443 K) due to the generation of Bronsted sites and increased coke formation rates, respectively. Deactivation of the catalyst is associated with a \"graphitic\" coke build up. The RON of the petrol fraction is 94.5 and the hydrogenated diesel fraction has a cetane number less than 35."]},{"key":"dc:title","label":"Title","values":["The oligomerization of propene over nickel synthetic mica-montmorillonite"]}]}],"canonical_facts":{"dc:contributor.advisor":["O'Connor, Cyril","Kojima, M"],"dc:creator":["Jacobs, Lester Lance"],"dc:date.accessioned":["2016-03-11T14:26:44Z"],"dc:date.available":["2016-03-11T14:26:44Z"],"dc:date.issued":["1987"],"dc:description":["Bibliography: pages 150-156."],"dc:description.abstract":["The catalytic oligomerization of propene to liquid fuels using synthetic mica montmorillonite (SMM) as well as the effect of incorporating nickel into the lattice and nickel, cobalt and zinc into the interlayer spaces was investigated. NiSMM is more active for propene oligomerization than SMM, although the product selectivity (60% of the oligomers boiled at above 453 K) is similar. The increase in activity of NiSMM is attributed to an increase in the surface acidity of the catalyst. The maximum activity over the nickel exchanged catalyst occurs at a nickel loading of 0.057 wt %. It is proposed that the bond strength of the acidic hydroxyl groups are perturbed by the polarizing effect of the divalent cation (Co, Zn or Ni) present in the interlayer spaces of SMM. The reduction of nickel, ion exchanged into SMM, removes the induction period associated with SMM and increases the catalyst lifetime. However, reduction of the lattice nickel results in a decrease in catalyst lifetime although the Bronsted acidity has increased. It is proposed that the metallic nickel present in reduced NiSMM may promote dehydrogenation of high molecular weight hydrocarbons thus causing rapid deactivation of the catalyst by increasing the formation of \"graphitic\" coke. The lifetime of NiSMM is greatly reduced by using a wet propene feed and reacting at higher temperatures (443 K) due to the generation of Bronsted sites and increased coke formation rates, respectively. Deactivation of the catalyst is associated with a \"graphitic\" coke build up. The RON of the petrol fraction is 94.5 and the hydrogenated diesel fraction has a cetane number less than 35."],"dc:identifier.uri":["http://hdl.handle.net/11427/17656"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Chemical Engineering"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["The oligomerization of propene over nickel synthetic mica-montmorillonite"],"dc:type":["Master Thesis"],"dc:type.qualificationlevel":["Masters"],"dc:type.qualificationname":["MSc"]},"updated_at":"2026-07-22T22:22:54Z"}