Fluidized bed method for producing p-xylene through shape-selective toluene and methanol alkylation

A p-xylene, alkylation technology, applied in the field of fluidized bed, can solve the problem of low selectivity of xylene, achieve the effect of improving selectivity, uniform temperature distribution, and reducing side reactions

Active Publication Date: 2014-02-19
SHANGHAI HUAYI GRP CO
View PDF5 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is the low selectivity of p-xylene in the prior art, and a new fluidized bed method for producing p-xylene by type-selective alkylation of toluene and methanol is provided

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
  • Fluidized bed method for producing p-xylene through shape-selective toluene and methanol alkylation
  • Fluidized bed method for producing p-xylene through shape-selective toluene and methanol alkylation
  • Fluidized bed method for producing p-xylene through shape-selective toluene and methanol alkylation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] in such as figure 1 In the reaction device shown, water is used as the terminator, the temperature of the terminator is 25°C, the injection position of the terminator is 1 / 10 of the height of the riser in the gas-solid separation area from the bottom of the gas-solid separation area, and the mole of raw material and terminator The ratio is 15:1, the catalyst is ZSM-5, SiO 2 / Al 2 o 3 The molar ratio is 100, the loading metal is 0.5wt%Pd, 8wt%La 2 o 3 , 5wt%P 2 o 5 . The raw materials of toluene and methanol are vaporized and mixed separately, and enter from the bottom of the fluidized bed reactor after heat exchange and preheating, and contact with the alkylation catalyst in the reaction zone to form a mixture rich in p-xylene. The reaction conditions are: reaction temperature 420°C , The reaction pressure is 0.1Mpa in terms of gauge pressure, the weight ratio of catalyst to raw material is 0.5:1, the molar ratio of methanol / toluene is 1:2, and the molar ratio of...

Embodiment 2

[0028] According to the conditions and steps described in Example 1, methanol is used as the terminator, the temperature of the terminator is 20 ° C, the injection position of the terminator is 1 / 5 of the height of the riser from the bottom of the gas-solid separation zone, and the mole of raw material and terminator The ratio is 1000:1, the catalyst is ZSM-5, SiO 2 / Al 2 o 3 The molar ratio is 500, the loading metal is 0.5wt%Pd, 8wt%La 2 o 3 , 5wt%P 2 o 5. The reaction conditions are: reaction temperature 600°C, reaction pressure 5Mpa based on gauge pressure, weight ratio of catalyst to raw material 20:1, methanol / toluene molar ratio=1:2, water vapor / toluene molar ratio=2:1, no impending hydrogen. The regeneration temperature of the regenerator is 560°C. 60% by weight of the catalyst in the toluene pre-contact zone passes through the inclined pipe to be regenerated to the regenerator for regeneration, and 40% returns to the reaction zone through the catalyst external c...

Embodiment 3

[0030] According to the conditions and steps described in Example 1, methanol is used as the terminator, the temperature of the terminator is 25 ° C, the injection position of the terminator is 1 / 5 of the height of the riser from the bottom of the gas-solid separation zone, and the mole of raw material and terminator The ratio is 30:1, the catalyst is ZSM-5, SiO 2 / Al 2 o 3 The molar ratio is 100, the loading metal is 5wt%Pd, 2wt%La 2 o 3 , 15wt%P 2 o 5 . The reaction conditions are: reaction temperature 420°C, reaction pressure 0.5Mpa in gauge pressure, weight ratio of catalyst to raw material 0.5, methanol / toluene molar ratio=1:2, CO / toluene molar ratio=2, no hydrogen. The regeneration temperature of the regenerator is 680°C. 5% by weight of the catalyst in the toluene pre-contact zone goes to the regenerator to regenerate through the inclined tube to be produced, and 95% returns to the reaction zone through the catalyst external circulation pipe after heat exchange. ...

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 relates to a fluidized bed method for producing p-xylene through shape-selective toluene and methanol alkylation, and mainly solves the problem of lower selectivity for p-xylene in the prior art. The fluidized bed method for producing the p-xylene through the shape-selective toluene and methanol alkylation comprises the steps as follows: 1), raw materials enter a reaction zone of a fluidized bed reactor after heated and are contacted with an alkylation catalyst, and a mixture flow of the p-xylene is generated; 2), the mixture flow enters a rapid gas-solid separation zone, a separated gaseous product enters a follow-up separation section, a separated catalyst enters a toluene pre-contact region, at least one part of the catalyst in the toluene pre-contact region enters a regenerator for regeneration after steam stripping by a steam stripping zone, and a regenerated catalyst is formed; and 3), the regenerated catalyst returns to the reaction zone for continuous reaction. With the adoption of the technical scheme, the problem is solved, and the method can be applied to p-xylene production.

Description

technical field [0001] The invention relates to a fluidized bed method for producing p-xylene by type-selective alkylation of toluene and methanol. technical background [0002] As the main raw material for the synthesis of terephthalic acid and dimethyl terephthalate, the demand for xylene, especially p-xylene, continues to grow. At present, the domestic and foreign industrial production processes of p-xylene mainly include toluene disproportionation, aromatics transalkylation, MTA process, etc., all of which have problems such as low raw material utilization rate and poor xylene selectivity. Adopting the toluene-methanol type-selective alkylation process to produce p-xylene, the production of benzene is low or even no benzene, which is in line with the current situation of excess benzene in the domestic market, and effectively improves the utilization rate of toluene raw materials. At the same time, the selectivity of p-xylene in the alkylation process is high, and there ...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C2/86C07C15/08
CPCY02P20/584
Inventor 祝然黄春红蒋福四唐建远蔡清白张新平唐勇张春雷
Owner SHANGHAI HUAYI GRP CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products