Catalytic cracking of Arabian Light VGO over novel zeolites as FCC catalyst additives for maximizing propylene yield. (1st March 2016)

• Record Type: Journal Article
• Authors: Hussain, A.I.; Aitani, A.M.; Kubů, Martin; Čejka, Jiří; Al-Khattaf, S.
• Is Part Of: Fuel. Volume 167(2016)
• Page Start: 226
• Page End: 239
• Publication Date: 2016-03-01
• Subjects: Catalytic cracking -- FCC additives -- 10-ring zeolites -- MCM-36 -- Propylene -- Light olefins; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2015.11.065
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Different structural types of zeolites (mostly 10-ring) were tested as additives increased VGO conversion. Increased rate of hydrogen transfer reactions decreased the yield of propylene. Maximum propylene yield of 10.9 wt.%, was achieved over ferrierite. Higher rate of cracking of iso-paraffins and olefins decreased gasoline yield. Kinetic parameters obtained over zeolite SSZ-74 showed lower activation energy. Abstract: Catalytic cracking of vacuum gas oil (VGO) was carried out in a microactivity test (MAT) unit. Commercial FCC USY catalyst (E-Cat) is used and modified by various zeolites with different pore structures, namely SSZ-74, SSZ-33, MCM-22, MCM-36, ZSM-5, TNU-9, IM-5, and ferrierite to enhance propylene yield. Adding zeolite additives to E-Cat increased catalyst activity. The highest propylene yield of ∼11 wt.% was achieved over ferrierite and MCM-36 compared with 7 wt.% over E-Cat. An increase in light olefins yield over all additives was associated with a decrease in gasoline yield due to the cracking of gasoline-range reactive species (mainly olefins and iso-paraffins). Zeolite SSZ-74 showed a good enhancement in light olefins yield up to 21.3 wt.% compared with 16.1 wt.% over E-Cat. It is found that additives with lower ability to carry bimolecular reactions are more selective to light olefins. Gasoline quality was improved as the octane number increased over E-Cat with all additives except MCM-36.