Kinetic studies for processes of liquid-phase alkylation of aromatics over solid acid catalysts

Abstract

The liquid-phase alkylation of aromatics has been effected traditionally with catalysis by inorganic acids or AlCl 3 and similar compounds. However the increasing importance of solid acid catalysts is changing the procedures in this field. One of the prerequisites for the development of relevant processes, and the design of reactors, is knowledge of the kinetic data in reactions catalyzed by solid acids. This review examines the information available on the kinetics of alkylations catalyzed by solid acids, mainly zeolites, supported metal chlorides and oxides, mesoporous (MCM) materials, and heteropolyacids, but also other less studied materials.

High-silica nanocrystalline Beta zeolites: efficient synthesis and catalytic application

“…The catalytic activity of these nanosized Beta zeolites has been studied for the alkylation of benzene with propylene to produce cumene, which is an important industrial intermediate product to obtain phenol and acetone. 16 This industrial process is mainly operated in the liquid phase using large pore zeolites as heterogeneous acid catalysts. 16 However, the design of large pore acid zeolites presenting nanosized crystals is convenient for this catalytic process, to reduce the restriction of cumene diffusion and to decrease the catalyst deactivation by olefin oligomerization and pore occlusion by multi-alkylated subproducts.…”

Kinetics of the reaction of toluene with benzyl alcohol over a Nafion–silica composite

“…As studies had already been carried out on the conversion of BzOH to BzOBz, and its reaction kinetics measured as a function of temperature [2], using the same solvent (cyclohexane) and the same catalyst, we were able, in the P. Beltrame, G. Zuretti / Applied Catalysis A: General 283 (2005) 33-38 34 Nomenclature C i molar concentration of i (mol/l) C cat weight concentration of catalyst (g/l) E act activation energy, from k 0 coefficients (kJ/mol) F objective function in the optimization procedure DH ads adsorption enthalpy, from K coefficients (kJ/mol) k o empirical rate coefficient (l/ (min g)) k am , k ad apparent rate coefficients (l 2 / (mol min g)) k ef apparent rate coefficient (l/ (min g)) k 0 am , k 0 ad , k 0 ef surface reaction rate coefficients (mol/(min g)) K BzA , K TOL , K NA , K M adsorption coefficients (l/mol) t time (min) y BzOH fractional conversion of benzyl alcohol Superscript 0 at time zero present work, to use these results with regard to reaction (3). Note that the Langmuir-Hinshelwood mechanism suggested for the etherification of benzyl alcohol [2] has, in a similar form, also been proposed for the analogous reaction of 1-octanol over zeolite BEA [21].…”

“…Within the same area of research, i.e. the alkylation of aromatics in liquid phase over solid acid catalysts [3], we are now directing our interest to benzyltoluenes. Mixtures of benzyl-and dibenzyltoluene have long been used as impregnants for power capacitors, being liquids of low viscosity and very low conductivity [4][5][6][7].…”

Nafion-Silica Nanocomposites: A New Generation of Water-Tolerant Solid Acids of High Efficiency

“…Detailed studies with respect to the kinetics of Friedel-Crafts alkylations with benzyl alcohols are available [55][56][57]. Important conclusions and general considerations including results acquired on other solid acids have been summarized in a review paper [58]. Nafion-SiO 2 catalysts prepared by ball milling were also evaluated in Friedel-Crafts alkylation [52].…”