Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

›› 2009, Vol. 17 ›› Issue (5): 761-766.

• CATALYSIS, KINETICS AND REACTORS • Previous Articles Next Articles

Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

XU Zehui^1,2, XIA Ronghui¹, GUO Shizhuo¹, FAN Cunliang¹, FANG Dingye²

1. SINOPEC Shanghai Petrochemical Company Limited, Chemical Research Institute, Shanghai 200540, China;
2. Department of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China

Received:2008-12-02 Revised:2009-08-09 Online:2009-10-28 Published:2009-10-28

Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

徐泽辉^1,2, 夏蓉晖¹, 郭世卓¹, 范存良¹, 房鼎业²

1. SINOPEC Shanghai Petrochemical Company Limited, Chemical Research Institute, Shanghai 200540, China;
2. Department of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China

通讯作者: XU Zehui,E-mail:spcxzh@163.com

Abstract

Abstract: The present work contributed to a new developed production method for enhancing the quality of isoamylene (IA) by adding a small amount of tertiary amyl alcohol (TAA) to the catalyst of strong acid cation exchange resin.TAA improved the selectivity of 2-methyl-2-butene (2M2B) at a high conversion level for the isomerization of IA.Compared with the other results from the current IA units,the conversion of 2-methyl-1-butene (2M1B),the mass ratio of 2M2B to 2M1B and the selectivity of 2M2B were increased from 0.5474,7.32 and 0.6864 to 0.72,12 and 0.95,respectively,while the dimers content in the products decreased from 4.38% to below 1.0%.Optimized conditions for IA isomerization consisted of temperature between 28 and 33℃ and system pressure of 0.5 MPa,weight hourly space velocity of 8.0 h^-1 with TAA mass fraction of 0.7%-0.9% in raw material.The results in lab supported bases for the developed process in industrial application which was later proved to be successful.In addition,a possible mechanism of the isomerization process was speculated to propose a key step of water formation in the TAA-added isomerization process and a verified experiment was conducted to support this speculation.

Key words: isoamylene, 2-methyl-1-butene, 2-methyl-2-butene, isomerization process, tertiary amyl alcohol

摘要： The present work contributed to a new developed production method for enhancing the quality of isoamylene (IA) by adding a small amount of tertiary amyl alcohol (TAA) to the catalyst of strong acid cation exchange resin.TAA improved the selectivity of 2-methyl-2-butene (2M2B) at a high conversion level for the isomerization of IA.Compared with the other results from the current IA units,the conversion of 2-methyl-1-butene (2M1B),the mass ratio of 2M2B to 2M1B and the selectivity of 2M2B were increased from 0.5474,7.32 and 0.6864 to 0.72,12 and 0.95,respectively,while the dimers content in the products decreased from 4.38% to below 1.0%.Optimized conditions for IA isomerization consisted of temperature between 28 and 33℃ and system pressure of 0.5 MPa,weight hourly space velocity of 8.0 h^-1 with TAA mass fraction of 0.7%-0.9% in raw material.The results in lab supported bases for the developed process in industrial application which was later proved to be successful.In addition,a possible mechanism of the isomerization process was speculated to propose a key step of water formation in the TAA-added isomerization process and a verified experiment was conducted to support this speculation.

关键词: isoamylene, 2-methyl-1-butene, 2-methyl-2-butene, isomerization process, tertiary amyl alcohol

XU Zehui, XIA Ronghui, GUO Shizhuo, FAN Cunliang, FANG Dingye. Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition[J]. , 2009, 17(5): 761-766.

徐泽辉, 夏蓉晖, 郭世卓, 范存良, 房鼎业. Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition[J]. , 2009, 17(5): 761-766.

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Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

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