Investigation of toluene alkylation with hept-1-ene over fresh and modified h-beta catalysts according to apparent activation energy values

This work has demonstrated improved conversion and selectivity and reduced coking in the alkylation of toluene with hept‑1-ene to linear alkyl methyl benzenes over onto H-beta (Si/Al = 367), desilicated H-beta (Si/Al = 231) and dealuminated H-beta (Si/Al = 563) zeolite catalysts. Additionally, kinetic modelling provided support for the proposed reaction mechanism, facilitating the design of improved catalysts for this reaction. The production of linear alkyl methyl benzenes is of critical import in the manufacture of detergents, a rapidly growing sector globally, however currently processes are limited by catalyst deactivation as a result of coke deposition. The properties of the parent and modified catalysts were analysed using XRD, FTIR, SEM, ICP-AES, TGA, and BET surface area. The results indicate that both types of catalysts whose structural framework was modified via acid or base leaching treatment techniques had improved catalytic activity, leading to an enhancement in the conversion and selectivity towards double-bond isomerisation and alkylation products. In addition, the experimental results were fitted using a reaction scheme consisting of seven components and thirteen reactions. Nonlinear optimization (genetic algorithm technique) with numerical integration (4th order Runge-Kutta) was utilized to predict the kinetic parameters, while Matlab 2021a software was used to perform all computation. The mean relative errors (MRE) values ​​estimated from comparing experimental and model-predicted outcome data showed remarkable agreement.