Unsymmetrical alkylation of benzene over large pore zeolites
- 作者：Sundaresan Sudha ; Muthaiahpillai Palanichamy ; Banumathi Arabindoo ; Velayutham Murugesan
- 关键词：Unsymmetrical alkylation ; Benzene ; Diethyl carbonate ; Isopropyl alcohol ; Zeolites
- 刊名：Catalysis Communications
- 出版年：2007
- 期刊代码：12_15667367
- 类别：ce
- 出版时间：July 2007
- 卷：8
- 期：7
- 页码：1137-1144
- 文件大小：166 K
摘要
One pot unsymmetrical alkylation of benzene with different alkylating agents is an interesting reaction, as the alkylated products have important commercial applications. Keeping this in view, one pot ethylation and isopropylation of benzene with diethyl carbonate and isopropyl alcohol were carried out over Hβ (Si/Al = 15), HY (Si/Al = 3) and HM (Si/Al = 10) zeolites in the vapour phase. In addition to homo-alkylated products, unsymmetrical dialkylated products were also obtained with significant selectivity. Nearly similar trend in selectivity was obtained over all the catalysts with increase in temperature. The zeolites with high density of acid sites are suggested to be beneficial for unsymmetrical alkylation, as they could provide more probability for the formation of both the alkyl cations together. The proper control of concentration of alkylating agents based on their formation and reactivity also appears to be important in enhancing unsymmetrical alkylation. The effect of temperature, feed ratio, WHSV and time-on-stream on the selectivity to unsymmetrical alkylation was studied and the results are presented in the manuscript.