Reaction performance of isobutane alkylation catalyzed by a composite ionic liquid at a short contact time

Abstract

Alkylate is an important clean blending component of gasoline due to the increased statutory reduction of the content of aromatics and olefins in commercial gasoline. The alkylation of isobutane with 2‐butene catalyzed by a composite ionic liquid was investigated. The composite ionic liquid showed efficient catalytic performance at a short contact time (10–60 s). The optimal conditions were: reaction temperature 15°C, contact time 20 s, ionic liquid to hydrocarbon volume ratio 1:1, and isobutane to olefin mole ratio 54:1. Under these optimal reaction conditions, the butene conversion was 100%, the yields of C8 and trimethylpentanes were 88.9 and 82.0%, respectively, the ratio of trimethylpentane to dimethylhexane was 11.9, and the alkylate research octane number (RON) was 97.3. A correlation model is developed to predict the product yields and the alkylate RON. The correlation model shows a low calculation error. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2244–2253, 2014

Alkylation of isobutane/isobutene using Brønsted–Lewis acidic ionic liquids as catalysts

“…This was attributed to the cracking of TMP occurring under longer reaction times and the cracking process tends to form C 5-7 products. Therefore, the optimal reaction time was 2.0 h. It has been reported in the literature that the alkylation of isobutane/2-butene can be carried out in the temperature range of À5°C to 15°C with a short contact time [1,28] because of the differences in the catalysts used leading to the different results of the alkylation reaction. The catalysts used in the literature were chloroaluminate ILs, which are super acidic catalysts.…”

“…Alkylate is a mixture of highly branched alkanes and has many advantages, such as high octane number, low Reid vapor pressure and octane sensitivity, and no aromatic compound and sulfur formation [1]. Therefore, alkylate is regarded as one of the few best choices to replace methyl tert-butyl ether, which is an excellent high octane number additive and anti-knock additive for gasoline.…”

Alkylation in Petroleum Processing

“…Researchers at China University of Petroleum (Liu et al 2014) have developed an alkylation process around a composite ionic liquid consisting of triethylamine hydrochloride chloroaluminate and CuCl. Various additives were tested as modifiers for the Et 3 NHCl-AlCl 3 , and CuCl gave the highest C 8 and TMP selectivities (Huang et al 2004).…”

Intensification of the Sulfuric Acid Alkylation Process with Trifluoroacetic Acid

“…However, the industrial application of solid catalysts is difficult because of their intrinsic defects, easy deactivation, and difficult regeneration. In addition, ionic liquids are considered to be promising catalysts for alkylation . The selectivity of trimethylpentane (TMP) can be as high as 85% when using ionic liquids as catalysts .…”