Investigate structure an‎d performance catalysts for the reaction of ethylene to 1-butene dimerization

1/1/1900 12:00:00 AM

The enhancement of the Titanium tetrabutoxide/Tetrahydrofuran/Triethylaluminium complex for ethylene dimerization to 1-butene (an important alphaolefin) was investigated. Following the synthesis of the complex an‎d extensive dimerization testing, dichloromethane (DCM) was identified as the superior promoter among halohydrocarbon can‎didates (DCM an‎d 1,2-dibromopropane (1,2-DBP)), while dicyclopentyldimethoxysilane (DCPDS) was selec‎ted as the optimal modifier among ester an‎d silane compounds. Experiments were conducted in a high-pressure/temperature stirred Büchi reactor, with gas chromatography used to analyze liquid an‎d gas phases. After selec‎ting the optimal promoter (DCM) an‎d modifier (DCPDS), both components were simultaneously incorporated into the Titanium tetrabutoxide/Tetrahydrofuran/Triethylaluminium catalyst complex at varying ratios. The Box Behnken Design (BBD) technique based on Response Surface Methodology (RSM) was employed, eva‎luating four key factors: catalyst, co-catalyst, modifier, promoter concentration an‎d temperature. Analysis of variance confirmed the statistical significance of the model for response variables (ethylene conversion, selec‎tivity, polymer content an‎d yield), demonstrating strong agreement between experimental an‎d predicted values. Optimization using Design Expert software showed values of 85.6%, 88.5%, 2.43 mg, an‎d 75.78% for ethylene conversion rate, selec‎tivity, polymer content an‎d yield, respectively, which showed an error of less than one percent compared to the laboratory results. Comparative analysis of catalyst performance with/without DCPDS an‎d DCM revealed that their inclusion increased conversion, selec‎tivity, an‎d efficiency by up to 85.3%, 88.2%, an‎d 75.2%, respectively, while simultaneously reducing undesirable polymer production from 185 mg to 2.4 mg.

بوتن-1، كاتاليست همگن، ديمريزاسيون، بهبوددهنده، ارتقادهنده، طراحي Box-Behnken

Butene-1, Homogeneous catalyst, Dimerization, modifier, promotor, Box-Behnken design,

Sajjad Bahrami Reyhan

Seyed Mahdi Alavi