Carbon-Based Materials Enhanced Emulsification To Improve Product Distribution in Isobutane/Butene Alkylation Catalyzed by Sulfuric Acid

Abstract

A series of carbon-based materials were illustrated to be efficient additives to improve the product distribution of isobutane/butene alkylation catalyzed by H 2 SO 4 . Among the tested materials, graphene oxide (GO) was shown to be the most efficient additive. With the presence of trace amounts (e.g., 0.1 wt %) of GO sheet, the weight percentage of C8 in the product could increase by ∼11% and research octane number (RON) of the alkylate was enhanced by ∼2. The presence of GO in H 2 SO 4 led to no obvious change of the acidity. The improved product distribution could be attributed to the enhanced emulsification and better dispersion of the reactants in the acid. The lifetime of the catalytic system was extended from 110 times (with no additive) to 140 times, as the formation of acid soluble oil was inhibited when the additive was present. This efficient and environmentally benign emulsifier could be a particularly promising additive for the current alkylation process catalyzed by H 2 SO 4 .

New Insights into the Progress on the Isobutane/Butene Alkylation Reaction and Related Processes for High-Quality Fuel Production. A Critical Review

“…A Most of the research has been evoked to liquid additives for the isobutane alkylation reaction, making the solid additives a significant area for development. In this sense, Meng 49 recently reported on the use of graphene oxide (GO) as solid additive to enhance the alkylate quality by first testing a series of carbonbased materials such as graphene, multiwall carbon nanotubes (MWCNTs), conductive black carbon, and also SiO 2 . The effects of all these solids were compared to those of liquid surfactants (Table 3) from where it is clear that GO reached the best alkylate in terms of TMP composition.…”

“…Effect of Additives on the Alkylate Product Distribution of Alkylate from Isobutane/Butene Alkylation Reactions49 …”

Improved H2SO4‐catalyzed alkylation reaction in a rotating packed bed reactor by adding additives

“…[ 36 ] Because acidity is also regarded as an essential property of an acid solution during the alkylation process, Li et al added caprolactam into H 2 SO 4 to adjust the acidity of the acid and improve the solubility of isobutane in the acid and investigated the optimal operating conditions for the high quality of alkylate. [ 37 ] Besides, graphene oxide [ 38 ] and some fluorine‐containing chemicals, such as trifluoroacetic acid, [ 23 ] thiophene, [ 39 ] [Bmim][SbF 6 ], [ 28,40 ] adamantane‐SbF 6 , [ 41 ] and triflic acid, [ 42 ] have been used as additives in H 2 SO 4 for the alkylation process to promote the yield of C 8 and high RONs. Table 1 shows the different effects on alkylation performance with the above additives.…”

Isobutane Alkylation Catalyzed by H2SO4: Effect of H2SO4 Acid Impurities on Alkylate Distribution

“…The catalysts for alkylation include concentrated H 2 SO 4 , hydrofluoric acid (HF), solid catalyst, ionic liquids, etc. ,,− Concentrated H 2 SO 4 is predominantly used as the catalyst for the industrial alkylation processes. , Nevertheless, H 2 SO 4 catalyst has many major drawbacks, including severe side reactions, high consumption of concentrated H 2 SO 4 (70–100 kg of H 2 SO 4 per metric ton of alkylates produced), and considerable energy consumption for treatment of used acid (regenerated H 2 SO 4 is 2–3 times more expensive than fresh H 2 SO 4 ) . These drawbacks have become increasingly prominent in recent years. − …”