Catalytic Cracking of Crude Oil: Mini Review of Catalyst Formulations for Enhanced Selectivity to Light Olefins

The direct conversion of crude oil to light olefins is consideredone the cheapest and most reliable sources of petrochemical primaryfeedstocks. Unlike in the past when refineries operated to produce mainlytransportation fuels, such as gasoline and diesel, many refineries worldwide areconsidering tandem production of both fuels and chemicals (particularly, lightolefins). To achieve this, refining technology, process optimization, andcatalyst formulations may have to be reconfigured. Developing active andselective catalysts for crude oil cracking thatfit into the current refinery systemwill go a long way in saving cost and time. In this review, catalyst formulationsfor the conversion of crude oil to light olefins have been discussed under theclassifications: zeolite components, tuning of zeolite porosity, and matrixmaterials. USY has been the common zeolite that is used in the cracking ofhydrocarbons to gasoline fractions, and ZSM-5 has the desired shapeselectivity for cracking of paraffins in gasoline fractions to light olefins. At thesame time, its low hydrogen transfer activity does not consume a large amountof generated light olefin, resulting in improvement of light olefin production.Various modifications of ZSM-5 composition have shown improvement in thelight olefin yield. The wide range of hydrocarbons in crude oil makes pore size tuning of the zeolite especially important. Matrixmaterials generally increase the attrition resistance, hydrothermal and chemical stability, metal entrapment ability, coke resistivity,andfluidizable catalyst formation. However, they can also affect (positively or negatively) catalyst arrangement and active siteproperties, which makes careful selection very important.

Automated summary

The direct conversion of crude oil to light olefins is considered a cost-effective and reliable method for obtaining petrochemical feedstocks. Refineries are shifting towards producing both fuels and chemicals, which requires reconfiguration of refining technology, process optimization, and catalyst formulations.