Alkylation of Isobutane and 2-Butene in Rotating Packed-Bed Reactors: Using Ionic Liquid and Solid Acid as Catalysts

Abstract

The alkylation of isobutane with 2-butene catalyzed by ionic liquid (IL)/solid acid (SA) was studied in this work. To improve the product quality, the rotating packed-bed (RPB) reactor was used to enhance the mass transfer of the alkylation process. Residence time, reaction temperature, the isobutane-to-olefins ratio, and the acid-to-hydrocarbon ratio all markedly affected the quality of alkylates. Under the optimal conditions, the research octane number could reach 99.8, and the amount of trimethylpentanes was 87.1 wt %. Because of the high efficiencies of mass transfer and micromixing, the RPB reactor can greatly improve the reaction efficiency of isobutane alkylation. By observing the droplets in RPB, the relationship between the average droplet diameter and the interfacial area was investigated. The droplet diameter and interfacial area were highly dependent on the physical parameters, such as the acid-to-hydrocarbon ratio, rotational speed, and the interface tension of acid–hydrocarbon. Moreover, a correlation model was proposed to calculate the interfacial area of the RPB reactor. A smaller droplet diameter and larger interfacial area are beneficial to the production of high quality alkylates. RPB is one of the promising industrial reactors for ionic liquid/solid acid alkylation.

H2SO4‐catalyzed isobutane alkylation under low temperatures promoted by long‐alkyl‐chain surfactant additives

“… 4 These disadvantages of conventional catalysts motivate researchers to develop novel candidates for C4 alkylation, such as solid acids and ionic liquids 5–9 . Although solid acids present a good initial activity and selectivity, the rapid deactivation is the inherent drawback to limit the large‐scale industrial application 10–12 . Also, the research about ionic liquids as novel catalysts for C4 alkylation has more rapidly grown owing to the process advantages, and the commercial use of ionic liquid‐based alkylation technology has been reported 9,13 .…”

Effect of Metal Precursors on the Performance of Pt/Y Catalysts for Isobutane-Butene Alkylation Reaction-Regeneration

“…Solid acid alkylation, which is the future growth path of alkylation, has the benefits of intrinsic safety, noncorrosion, and green environmental protection. − Among the various solid acid catalysts, molecular sieve catalysts are particularly advantageous due to their homogeneous pore structure distribution, large specific surface area, and abundant acid sites. Consequently, they have been extensively researched in the isobutane-butene alkylation process. , However, zeolite catalysts deactivate easily, have a short cycle life, and require frequent regenerations. , Metal hydrogen regeneration is a successful option for regeneration.…”

Target high‐efficiency ionic liquids to promote H2SO4‐catalyzed C4 alkylation by machine learning

“…Simultaneously, solid acids and ionic liquids (ILs) are considered as novel catalyst candidates. The current alkylation still strongly relies on the H 2 SO 4 as catalyst, 2–6 because of the potential leakage risks of HF, rapid deactivation of solid acids, and the high operating cost and difficult disposal of spent ILs 7–9 . However, the H 2 SO 4 catalyst also has several fatal drawbacks, including serious equipment corrosion, huge spent acid, and secondary pollution caused by disposal of spent acid.…”