Toluene ethylation with ethanol on cadmium-promoted high-silica zeolite

Influence of modification on acidic and catalytic proper-ties of high-silica zeolites in the reaction of alkylation of toluene with isopropanol

“…The alkylation of aromatic hydrocarbons with different type of alcohols are applied on a large scale in the chemical industry 1 . Among para-dialkylated aromatics p-xylene, p-diizoprophylbenzene, pdiethylbenzene, p-and m-cymenes and p-izopropyltoluene are very important in tine chemical and petrochemical industries [2][3][4][5][6][7] and the above products are alkylated-aromatic products. Traditionally, it was manufactured by alkylation of aromatic hydrocarbons with alcohols using AlCl3 or phosphoric acid supported on silica 5,8 .…”

“…In recent years, high-silica zeolites such as mordenite 14,15 and pentasil are widely used as promising catalysts for the production of para-substituted alkylaromatic hydrocarbons [16][17][18][19] . One possible way to change the catalytic and molecular-sieve properties is directional pore regulation and modification of acid sites by removing the strongest acid centres and changing their nature 6,7,16 . It was shown that the modification of HS-zeolites with cadmium, phosphorus, lantan, magnesium and silica compounds exerts a para-orienting effect on its activity in the methylation and ethylation reactions of alkylaromatic hydrocarbons 6,7,17,20, .…”

Shape-Selective Alkylation of Toluene with Ethanol over a Twin Intergrowth Structured ZSM-5: Modulation of Acidity and Diffusivity via Interface Engineering

“…2−5 ZSM-5 zeolite, with tunable acidity, unique three-dimensional pore structure, and high hydrothermal stability, is a commonly used catalyst for the alkylation of toluene with ethanol. 6,7 However, on the conventional ZSM-5 catalyst, the three ET isomers are thermodynamically distributed (p-ET (25.9%), meta-ethyltoluene (m-ET, 59.3%), and ortho-ethyltoluene (o-ET, 14.8%)), 6 which requires a costly and energy-intensive process to separate p-ET from the isomers with near boiling points. Therefore, improving the para-selectivity is a cost-effective and relatively simplified process.…”

“…Ethyltoluene (ET) is a crucial raw material in the chemical industries, especially para -ethyltoluene ( p -ET), which is used for producing poly­( p -methylstyrene) to meet the rapidly growing demand . Recently, in light of the overcapacity of toluene and the inexpensive ethanol produced from biomass fermentation, the alkylation of toluene with ethanol has emerged as a promising route to produce ET and balance the supply-demand of aromatics. − ZSM-5 zeolite, with tunable acidity, unique three-dimensional pore structure, and high hydrothermal stability, is a commonly used catalyst for the alkylation of toluene with ethanol. , However, on the conventional ZSM-5 catalyst, the three ET isomers are thermodynamically distributed ( p -ET (25.9%), meta -ethyltoluene ( m -ET, 59.3%), and ortho -ethyltoluene ( o -ET, 14.8%)), which requires a costly and energy-intensive process to separate p -ET from the isomers with near boiling points. Therefore, improving the para -selectivity is a cost-effective and relatively simplified process.…”

Alkylation of Ethylbenzene by Ethanole on H-Ultrasil Zeolite Catalyst, Modified by Lantanum

“…H-ultrasil zeolite could be the best catalyst for the reaction of ethylbenzene ethylation by ethanol to p-DEB because of its special shape selectivity and surface acidity. Many processes have been developed to modify its surface property in order to promote para-selectivity for alkylation and prevent coking deposition: for example, loading with oxide of P, Mg or B [6][7][8][9][10][11][12], coking by methanol [11][12][13], silylation by silicon alkoxide [14,15] using Hultrasil zeolites of different crystal sizes [16,17] and use of metallosilicate zeolites with the MFI structure [18][19][20]. Modified H-ultrasil zeolites exhibit high para-selectivity than the parent zeolite.…”