Method for producing p-xylene, o-xylene and 1,2,4-trimethylbenzene from coal-based raw materials

A technology of p-xylene and p-trimethylbenzene, which is applied in chemical instruments and methods, bulk chemical production, purification/separation of hydrocarbons, etc., can solve the problems of poor economy and high cost, and achieve coking delay, high activity, The effect of good reaction stability

Inactive Publication Date: 2017-12-15
TONGJI UNIV
View PDF6 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Generally speaking, the cost of alkylation of pet

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
  • Method for producing p-xylene, o-xylene and 1,2,4-trimethylbenzene from coal-based raw materials
  • Method for producing p-xylene, o-xylene and 1,2,4-trimethylbenzene from coal-based raw materials
  • Method for producing p-xylene, o-xylene and 1,2,4-trimethylbenzene from coal-based raw materials

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] figure 1 Shown is a typical process flow of the method for producing p-xylene, o-xylene and mesitylene from coal-based raw materials in the present invention. Using crude methanol (90%) produced from coal synthesis gas and coked crude benzene (containing 91.6% benzene, 7.0 wt% toluene, 1.3 wt% xylene and 0.1 wt% other impurities) as raw materials, the coked crude benzene was washed with sulfuric acid, Hydrogenation pretreatment (NiO-MoO 3 and Co-MoO 3 Catalyst, fixed bed), and the crude methanol enters the alkylation reactor (fluidized bed) for catalytic reaction, and the obtained products are mainly toluene, mixed xylene, trimethylbenzene, a small amount of heavy aromatics and light hydrocarbons. The above products enter the rectification system together, and first pass through the stripping tower to separate light hydrocarbons as fuel for the device; the heavy components flowing out of the stripping tower pass through the benzene tower to separate and obtain unconve...

Embodiment 2

[0038] The differences between this example and Example 1 are: 1) The raw material of coal-based methanol is crude methanol produced from coal coke oven gas (methanol content 93.0 wt%); 2) The raw material of coal-based benzene is obtained by lightening heavy components of coal tar Crude benzene, containing 79.8% benzene, 15.0 wt% toluene, 5.0 wt% xylene and 0.2 wt% other impurities; 3) The alkylation reactor uses a fixed-bed reactor. 4) The catalyst used in the alkylation reaction is 0.02% Ce 2 o 3 Nanoacicular ZSM-5 molecular sieve modified with 0.1% MgO, with an external specific surface area of ​​98m 2 / g, the number of acid sites on the outer surface accounts for 37% of the total number of acid sites, and the number of weak and moderately strong acid sites accounts for 98.1% of the total number of acid sites; the alkylation reaction conditions are: the moles of methanol and aromatics (benzene+toluene) The ratio is 1:1, the reaction pressure is 2.0 MPa, the reaction temp...

Embodiment 3

[0040] The differences between this example and Example 1 are: 1) coal-based benzene is coking benzene (containing 99.79% benzene, 1.0 wt% toluene, 0.2wt% xylene and 0.01 wt% other impurities); 2) coal-based methanol raw material Crude methanol (methanol content: 80.0 wt%) was produced from coal synthesis gas; 3) The alkylation reactor was a moving bed reactor. 4) The catalyst used in the alkylation reaction is a sheet-like MCM-49 / nano-Beta composite molecular sieve modified with 5.0%CdO and 5.0%CuO, with an external specific surface area of ​​91 m 2 / g, the number of acid sites on the outer surface accounts for 32% of the total number of acid sites, and the number of weak and moderately strong acid sites accounts for 95.1% of the total number of acid sites; the alkylation reaction conditions are: the moles of methanol and aromatics (benzene and toluene) The ratio is 1:2, the reaction pressure is 5.0 MPa, the reaction temperature is 700°C, the molar ratio of water to raw mater...

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 method for producing p-xylene, o-xylene and 1,2,4-trimethylbenzene from coal-based raw materials. P-xylene, o-xylene and 1,2,4-trimethylbenzene are produced from raw materials including crude benzene and crude methanol by acid pickling, hydrogenation pretreatment, alkylation reaction, rectification, crystal separation and isomerization reaction by virtue of an alkylation catalyst having large outer specific surface area and mainly adopting weak acid and medium-strong acid as main components as well as an anti-coking alkylation reaction medium; the used catalyst is flake-like MCM-56, nanometer needle-like ZSM-5, flake-like MCM-49 or a nanometer Beta molecular sieve modified by two metal oxides or a compound thereof; and a novel special molecular sieve based catalyst is also used for isomerization, alkyl transfer and shape selective disproportionation reaction which are all carried out in a fixed bed reactor. By using the method, the production costs of p-xylene, o-xylene and 1,2,4-trimethylbenzene can be effectively reduced, and the aim of producing aromatic products according to a non-petroleum raw material route is thoroughly achieved.

Description

technical field [0001] The invention relates to a method for producing p-xylene (PX), o-xylene (OX) and mesitylene with coal-based raw materials. The method uses cheap coal-based crude benzene and coal-based methanol as raw materials, adopts a new type of alkylation catalyst with a large external specific surface area, weak acid and medium strong acid, and an anti-coking alkylation reaction medium. Processes such as hydrogen pretreatment, alkylation reaction, rectification, crystallization separation, isomerization reaction and material circulation, realize the non-petroleum route and low-cost production of the above three chemical products; optionally, the method further includes toluene Shape-selective disproportionation reaction, transalkylation reaction; and the combination of incoming and outgoing materials through each operating unit to flexibly adjust the product structure. Background technique [0002] Para-xylene (PX) is the basic raw material of aromatic hydrocarb...

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): C07C2/86C07C5/27C07C6/12C07C7/00C07C7/04C07C7/14C07C7/10C07C7/163C07C15/08C07C15/02C07C15/04B01J29/40B01J29/70B01J29/76B01J29/80B01J29/85
CPCB01J29/405B01J29/7088B01J29/7276B01J29/7615B01J29/80B01J29/85C07C2/864C07C5/2737C07C6/126C07C7/005C07C7/04C07C7/10C07C7/14C07C7/163C07C2529/40C07C2529/70C07C2529/76C07C2529/80C07C2529/85C07C15/06C07C15/08C07C15/02C07C15/04Y02P20/52
Inventor 朱志荣李军辉赵国庆李明
Owner TONGJI UNIV
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