Unlock instant, AI-driven research and patent intelligence for your innovation.

Compound catalyst and method for preparing styrene

A catalyst and styrene technology, applied in chemical instruments and methods, organic compound/hydride/coordination complex catalysts, physical/chemical process catalysts, etc., can solve the loss of catalysts and styrene, the intensification of side reactions of heavy components, High reaction temperature and other problems, to achieve the effect of increased device operation flexibility, reduced residence time, and small reactor volume

Active Publication Date: 2020-02-11
WANHUA CHEM GRP CO LTD
View PDF11 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] At the same time, the acidic catalyst with a large molecular weight is easy to polymerize with styrene, resulting in a large amount of catalyst used, and the side reaction of generating heavy components is intensified
In addition, the traditional tank reactor has a large volume and high reaction temperature, which leads to serious corrosion of the reactor
[0008] In order to solve the above problems, one of the current methods for synthesizing styrene is to use 1-phenylethanol to carry out reactive distillation dehydration under high temperature and reduced pressure conditions, but the reaction and separation are carried out in the same equipment, the dehydration effect is poor, and the reaction residence time is long , the reaction product and catalyst cannot be separated from the heavy component in time, and styrene and the heavy component are further polymerized, which cannot fundamentally avoid the reduction of the overall yield caused by the polymerization of styrene
[0009] At the same time, liquid-phase dehydration uses a catalyst of p-toluenesulfonic acid macromolecule. In order to ensure a high conversion rate of 1-phenylethanol in a traditional reactor, a large amount of catalyst needs to be added, and these catalysts will also participate in the polymerization of styrene, resulting in catalyst and benzene double loss of ethylene

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Compound catalyst and method for preparing styrene
  • Compound catalyst and method for preparing styrene
  • Compound catalyst and method for preparing styrene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1～11

[0056] Control the pressure of the flash tank at 50kPa, the pressure at the top of the separation tower at 30kPa, the temperature of the dehydration reactor at 200°C and the pressure at 50kPa, based on the weight of the freshly added 1-phenylethanol feedstock, the ratio of methanesulfonic acid and p-phenolic acid The compound catalyst is added according to the compound ratio n, and the circulation ratio (the weight of the heavy component of the circulating circulating reaction medium to the feed mass ratio of the freshly added 1-phenylethanol) is 10:1 to 32:1. The obtained styrene-containing material is adsorbed and deacidified by D301 alkaline resin, and the space velocity of the resin adsorption bed is 0.5BV. The results are shown in Table 1 below.

[0057] Table 1

[0058]

[0059]

Embodiment 12～18

[0061] The circulation ratio is 15 and the residence time is 60s. Based on the weight of the freshly added 1-phenylethanol raw material, the methanesulfonic acid and p-phenolic acid catalysts are compounded in a ratio of 1:1, the compounded catalyst is added at 100 ppm, and the flash tank pressure is P 1 kPa, separation tower top pressure P 2 kPa, where the pressure of the dehydration reactor is the same as the pressure of the flash tank, which is P 1 kPa. The obtained styrene-containing material is adsorbed and deacidified by D301 alkaline resin, and the space velocity of the resin adsorption bed is 0.5BV. The results of the reaction are shown in Table 2.

[0062] Table 2

[0063]

[0064]

[0065] The results show that by controlling the temperature of the dehydration reactor R-1 and adjusting the circulation ratio, the conversion rate of 1-phenylethanol can reach more than 98%, and the selectivity can reach more than 98.5%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for preparing styrene. 1-phenethyl alcohol is dehydrated in the presence of a compound catalyst formed by compounding methanesulfonic acid with one or two of p-methoxyphenol and a p-phenolformic acid inhibitor to generate styrene. The compound catalyst and the method for preparing styrene have the advantages of realization of respective circulation of the dehydration catalyst and the side reaction inhibitor, low total dosage of the compound catalyst, reduction of byproducts, increase of the conversion rate, and realization of the styrene selectivity of 98.5% orabove.

Description

Technical field [0001] The invention relates to a compound catalyst and method for preparing styrene, in particular to a method for preparing styrene from raw materials containing 1-phenylethanol through external circulation reaction and rectification. Background technique [0002] Styrene is an important basic organic chemical raw material, mainly used to produce polystyrene resin (PS), acrylonitrile-butadiene-styrene terpolymer (ABS), styrene-acrylonitrile copolymer (SAN) )Wait. In addition, it can also be used in industries such as pharmaceuticals, dyes, pesticides, and mineral processing, with a wide range of uses. [0003] There are mainly two known methods for preparing styrene: (1) Direct thermal dehydrogenation of ethylbenzene catalyzed to prepare styrene; (2) The method used for the joint preparation of styrene and propylene oxide is generally called For the POSM method, a patent describing the method is US No. 3,351,635. Generally speaking, the POSM method includes the ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C07C1/24C07C15/46B01J31/04B01J31/02
CPCC07C1/24C07C15/46B01J31/04B01J31/0225B01J31/0204
Inventor 冷炳文董岩峰叶建初虞根海刘洋洋胡亚东张宏科
Owner WANHUA CHEM GRP CO LTD