Catalytic performance of Cu-and Zr-modified beta zeolite catalysts in the methylation of 2-methylnaphthalene

• 来源期刊: 石油科学（英文版）
• 年，卷（期）: 2019,（1）
• 页码范围: 161-172
• 页数: 12页
• 语种: 英文

摘要

2,6-Dimethylnaphthalene (2,6-DMN) is a commercially important chemical for the production of polyethylenenaphthalate and polybutylene naphthalate.However,its complex synthesis procedure and high production cost significantly reduce the use of 2,6-DMN.In this study,the synthesis of 2,6-DMN was investigated with methylation of 2-methylnaphthalene (2-MN) over metal-loaded beta zeolite catalysts including beta zeolite,Cu-impregnated beta zeolite and Zr-impregnated beta zeolite.The experiments were performed in a fixed-bed reactor at atmospheric pressure under a nitrogen atmosphere.The reactor was operated at a temperature range of 400-500 ℃ and varying weight hourly space velocity between 1 and 3 h-1.The results demonstrated that 2,6-DMN can be synthesized by methylation of 2-MN over beta type zeolite catalysts.Besides 2,6-DMN,the product stream also contained other DMN isomers such as 2,7-DMN,1,3-DMN,1,2-DMN and 2,3-DMN.The activity and selectivity of beta zeolite catalyst were remarkably enhanced by Zr impregnation,whereas Cu modification of beta zeolite catalyst had an insignificant effect on its selectivity.The highest conversion of 2-MN reached 81％,the highest ratio of 2,6-DMN/2,7-DMN reached 2.6 and the highest selectivity of 2,6-DMN was found to be 20％ by using Zr-modified beta zeolite catalyst.