Isomerization of n-C5/C6 Bioparaffins to Gasoline Components with High Octane Number

Abstract

The thermal and catalytic conversion processes of alternative feedstocks (e.g., waste and biomass) to different engine fuels can result in the formation of a significant amount of light hydrocarbons as by-products in the boiling range of gasoline. The properties of these C5/C6 hydrocarbons need to be improved due to many reasons, e.g., their benzene content, and/or poor oxidation stability (high olefin content) and low octane number (<60). The aim of the research work was to increase the octane number of benzene containing C5/C6 bioparaffin fractions by catalytic isomerization. These by-products were obtained from special hydrocracking of waste cooking oil to hydrocarbons in the boiling range of aviation turbine fuels (JET fuels)/diesel fuels. Experiments were carried out in a reactor system containing down-flow tubular reactors over Pt/Al2O3/Cl and Pt/H-Mordenite/Al2O3 catalysts at 115–145 °C and 230–270 °C, respectively. Based on the results obtained at different process parameter combinations, it was concluded that the hydrogenation of benzene was complete over both catalysts, and the liquid yields were higher (ca. 98% > ca. 93 %) in the case of Pt/Al2O3/Cl. In addition, the octane number was also enhanced (ca. 32 > ca. 27 unit) in the products compared to the feedstock. This was because a higher isoparaffin content can be obtained at a lower operating temperature. Moreover, cracking side reactions take place to a lesser extent. The utilization of these isomerized bio-origin light fractions can contribute to the competitiveness of second-generation biofuels.

Catalytic Activity of Pt Loaded Zeolites for Hydroisomerization of n-Hexane Using Supercritical CO2

“…The total weight losses were observed as 7.41 and 5.58% for Pt/H-ZSM-5 and Pt/H-MOR, respectively. Our results are correlated with the previously reported studies, Tamizhdurai et al3 stated that a maximum weight loss of about 7.92, 9.67, and 6.96% were observed for ZSM-5(10), ZSM-5(50), and ZSM-5(5.4) zeolites, respectively at 320−530 °C. The weight loss occurred…”

“…n -Hexane isomerization reaction results in four major different types of iso -C 6 isomers including 3-methylpentane (3-MP), 2,2-dimethylbutane (2,2-DMB), 2-methylpentane (2-MP), and 2,3-dimethylbutane (2,3-DMB). 2-MP and 3-MP are the most required compounds for upgrading of motor gasoline due to their sufficient volatility and high-octane number . Therefore, it was worth examining the effectiveness of Pt loaded H-ZSM-5 and H-MOR catalysts toward the yield of these compounds.…”

“…2-MP and 3-MP are the most required compounds for upgrading of motor gasoline due to their sufficient volatility and high-octane number. 50 Therefore, it was worth examining HC ratio of 9. Findings also revealed that temperature impact on the production of C 1 −C 5 hydrocarbons produced interesting results.…”

Emerging Tools for Energy System Design Increasing Economic and Environmental Sustainability

“…The next paper, "Isomerisation of n-C5/C6 Bioparaffins to Gasoline Components with High Octane Number", authored by Hancsók et al [87], addresses the challenges of producing fuels from alternative sources such as waste and biomass. These fuels often contain by-products, e.g., light hydrocarbons, especially n-alkanes C5-C7, which reduce the quality and negatively affect the safety properties of the fuel.…”

Mobility and separation of linear and branched C5 alkanes in UiO-66 (Zr) probed by 2H NMR and MD simulations

“…After isomerization, nalkanes that have not been converted to branched alkanes are returned to the reactor. [1][2][3] Therefore, a mixture of branched and linear alkanes has to be separated. For light hydrocarbons, the typical boiling points of their isomers are relatively close which makes basic separation methods like cryo-distillation extremely energy consuming.…”