Catalytic Studies toward Synthesis of 2,6-Dimethylnaphthalene from 1-(p-Tolyl)-2-methylbutane
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- 作者：Kari Vahteristo ; Kari-Matti Sahala ; Salme Koskimies
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2010
- 出版时间：May 5, 2010
- 年：2010
- 卷：49
- 期：9
- 页码：4018-4025
- 全文大小：227K
- 年卷期：v.49,no.9(May 5, 2010)
- ISSN：1520-5045
文摘
In this work experiments have been performed in order to study the synthesis of 2,6-dimethylnaphthalene (DMN) via dehydrocyclizing 1-(p-tolyl)-2-methylbutane over Pt/SiO2, V/Ca/Al2O3, and unimpregnated or potassium-impregnated Cr2O3/Al2O3 catalysts. The obtained liquid product mixture consisted of 1,6-cyclization products (dimethylnaphthalenes) and dealkylated 1,6-cyclization products (2-methylnaphthalene and naphthalene), 1,5-cyclization products (trimethylindanes and -indenes), and fragmentation products (mainly p-xylene and 3-(p-tolyl)-propylenes) and 1-(p-tolyl)-2-methylbutenes. Among 10 possible DMN isomers 1,5-, 1,6-, 2,6-, and 2,7-DMN were identified. Metal catalysts V/Ca/Al2O3 (5 wt % vanadium) and Pt/SiO2 (1 wt % platinum) were slightly more active than unimpregnated commercial Cr2O3/Al2O3. After 1 h on-stream time the conversion of 1-(p-tolyl)-2-methylbutane was 96 mol % when the artificial contact time (1/weight-hourly space velocity (WHSV)) was 5.7 h at 783 K over unimpregnated Cr2O3/Al2O3. Potassium impregnation decreased the conversion into 84 mol % because of the decreased Brunauer−Emmett−Teller surface area (from 97 m2/g unimpregnated to 70 m2/g potassium-impregnated catalyst).