Skip to main content
main-content

Über dieses Buch

This book provides a comprehensive description of the catalytic technologies for selective hydrogenation of benzene to cyclohexene. Focusing on selective hydrogenation of benzene to prepare cyclohexene and its downstream products, such as cyclohexanone, bulk chemicals and high-value fine chemicals, it also discusses the objective laws, reaction mechanisms and scientific significance based on experimental data, analysis and characterization results. Given its scope, the book will appeal to a broad readership, particularly professionals at universities and scientific research institutes, senior undergraduates, master's and doctoral graduate students as well as practitioners in industry.

Inhaltsverzeichnis

Frontmatter

Chapter 1. An Overview of the Catalytic Selective Hydrogenation Technologies of Benzene into Cyclohexene

Abstract
Selective hydrogenation of benzene from the fossil and coal companies into cyclohexene and its downstream products including bulk chemicals of cyclohexanone, adipic acid, hexanolactam, nylon 6, nylon 66, and high value fine chemicals of medicine, pesticide, and perfumes are of great significance for the economic development. Compared with the traditional process of benzene, hydrogenation into cyclohexane is safe, resource saving, environmentally friendly, and has giant economic and social benefits for the selective hydrogenation of benzene into cyclohexene.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 2. Benzene Selective Hydrogenation Thermodynamics, Heterogeneous Catalytic Kinetics Catalysis Mechanism and Scientific Essence

Abstract
It is disadvantageous in thermodynamics for benzene selective hydrogenation to cyclohexene. The reaction route and rate-controlling step could be changed through multiphase catalysis and the high selectivity of cyclohexene under the high conversion of benzene. The thermodynamic results reveal that the selective hydrogenation of benzene should proceed under suitable temperature and pressure.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 3. The First-Generation Catalyst for Selective Hydrogenation of Benzene to Cyclohexene-Ru–M–B/ZrO2(M=Fe, La) Amorphous Alloys

Abstract
In 1989, Japan, firstly industrialized the selective hydrogenation of benzene to cyclohexene and the downstream products catalytic technology. Their technologies were transferred to our country in 1995 and 2005, respectively. The main technical indexes of the first-generation catalyst were as follows: the conversion of benzene was 40%, the selectivity of cyclohexene was 80%, and the yield of cyclohexene was 32%. For the second-generation catalyst: benzene conversion was 51%, cyclohexene selectivity was 77.7%, and cyclohexene yield was 40%. However, due to the lack of technology for catalyst preparation, the autonomic and sustainable development of domestic enterprise has been restricted seriously.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 4. The Second-Generation Catalyst for Selective Hydrogenation of Benzene to Cyclohexene-Ru-Zn-Na2SiO3-PEG-10000

Abstract
The main technical indexes of the second-generation of catalysts, Ru-Zn-Na2SiO3-PEG-10000, are as follows: conversion of benzene was 50%, selectivity of cyclohexene was over 80%, yield of cyclohexene was more than 42%, reached the second-generation of similar catalyst level abroad. Compared with the first generation amorphous alloy Ru-M-B/ZrO2, the second-generation catalyst belongs to the crystalline structure with better thermal stability and longer service life. Because of the modification of Na2SiO3-PEG-10000 on the surface of the catalyst, it has better catalytic activity and cyclohexene selectivity, the conversion rate of benzene increased by 10 percentage points, and the cyclohexene yield increased by 8 percentage points.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 5. Third-Generation Catalyst of Benzene Selective Hydrogenation to Cyclohexene—Ru–M (Zn, Mn, Fe, La, Ce) Nano-bimetallic System

Abstract
The third-generation catalyst of benzene selective hydrogenation, i.e., the Ru–M (Zn, Mn, Fe, La, Ce) nano-bimetallic system belongs to the nanocrystallite, compared with the first-generation amorphous alloy of Ru–M–B/ZrO2. Additionally, the promoters are extended to other transition elements and rare earth elements, without Na2SiO3-PEG-10000 modifier, when compared with the second-generation Ru–Zn–Na2SiO3-PEG-10000 catalyst. The main technical indexes of the third-generation catalyst are as follows: benzene conversion of 60%, cyclohexene selectivity of more than 80%, cyclohexene yield of more than 48%, compared with that of the second-generation catalyst, benzene conversion increases by 10 percentage points, cyclohexene yield increases by 8 percentage points.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 6. Fourth-Generation Catalyst of Benzene-Selective Hydrogenation to Cyclohexene—Ru–Zn@BZSS Core-Shell Catalyst

Abstract
Compared with the preparation technology of the third-generation catalyst for benzene-selective hydrogenation, the fourth-generation Ru–Zn@BZSS core-shell catalyst overcomes the technical bottleneck of in situ preparation method of the BZSS salt. The surface modification of the catalyst by using the non-in situ prepared BZSS improves the selectivity and yield of cyclohexene, and the controllable preparation of the catalyst can be achieved. The main technical indicators of the catalyst are as follows: benzene conversion of 70%, cyclohexene selectivity of more than 80%, cyclohexene yield of more than 56%. Compared with the third-generation catalysts, the benzene conversion of the fourth-generation catalysts increased by 10% points, and the cyclohexene yield increased by 8% points.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 7. Modulation of Activity and Selectivity of the Catalyst for Benzene Selective Hydrogenation

Abstract
Benzene selective hydrogenation catalysts were applied in the industrial process. With the prolonging of reaction time and the fluctuations of reaction conditions, the activity and selectivity of catalysts may deviate from the normal value. Timely measures to restore the main technical indicators of the catalysts to the normal level are known as activity and selectivity modulation.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 8. Catalyst Deactivation and Regeneration in Benzene Selective Hydrogenation

Abstract
For a set of 100,000–200,000 t/a industrial plant for benzene selective hydrogenation to produce cyclohexene and its downstream products, the initial loading of Ru catalyst is 200–400 kg for benzene selective hydrogenation, the life expectancy of the catalyst is about 2 years. During the operation of the device, the loss will be significant when the catalyst is inactivated due to improper operation or the introduction of impurities. If the deactivated catalyst cannot be regenerated in situ, it not only needs tens of millions of dollars to replace the catalyst, but also needs to discharge the mother liquor causing pollution. Therefore, it is very important to study the deactivation mechanism of catalyst for benzene selective hydrogenation and the regeneration method to ensure the normal production of industrial production.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 9. The Catalytic Technologies and Key Facilities for Benzene Selective Hydrogenation

Abstract
In foreign countries, the agitated high-pressure reaction kettle is used in industrial devices for selective hydrogenation of benzene, however, only a few countries could produce the key components all over the world. Moreover, this large-scale autoclave manufacturing technology is monopolized by several multinational corporations, limiting China’s industrialization process for selective hydrogenation of benzene.
Zhongyi Liu, Shouchang Liu, Zhongjun Li

Chapter 10. Selective Hydrogenation of Benzene to Cyclohexene and Incorporate Device of Its Downstream Products

Abstract
In 2010, the selective hydrogenation of benzene to cyclohexene and the catalytic technology of its downstream products were industrialized in China. In the patented invention patent, “A device of benzene selective hydrogenation” is conducive to control the reaction temperature and improve the reaction rate, and thus the catalyst has high selectivity and cyclohexene yield.
Zhongyi Liu, Shouchang Liu, Zhongjun Li
Weitere Informationen