Density functional theory study of side-chain alkylation of toluene with formaldehyde over alkali-exchanged zeolite

作者：Wang, Yang; Zhu, Mingyuan; Kang, Lihua^*; Dai, Bin

来源：Microporous and Mesoporous Materials, 2014, 196: 129-135.

DOI：10.1016/j.micromeso.2014.05.007

• Alkylation
• Co-adsorption
• DFT
• Side-chain
• Toluene

The adsorption of the alkali-metal cation (M = Li+, Na+, K+, Rb+, and Cs+) and the reaction mechanism of the side-chain alkylation of toluene with formaldehyde over MY basic zeolite (M = Rb+ and Cs+) were investigated using density functional theory calculations. During co-adsorption, the zeolite adsorbs toluene preferentially and then formaldehyde. The side-chain alkylation in MY zeolite (M = Rb+ and Cs+) consists of the following two steps: toluene reacts with formaldehyde to obtain phenyl ethanol, and then the intramolecular dehydration of phenyl ethanol produces styrene and water. Phenethyl alcohol dehydroxylation is the rate-controlling step. Although the activation energy is similar in Rb+- and Cs+-modified zeolite (63.09 and 62.20 kcal mol(-1)), the products are much easily removed from the system in Cs+-modified zeolite. Scilicet, Cs+-modified zeolite is a suitable catalyst during the side-chain alkylation of toluene.

• 出版日期2014-9-15
• 单位石河子大学