Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Improved acetic acid purifying method

A purification method and acetic acid technology, which are applied in the purification field of low-pressure methanol oxo synthesis of acetic acid, can solve the problems of pollutant flow, heavy phase removal step pollution, high energy consumption, etc., and achieve increased reaction yield, reduced energy consumption, and less by-products Effect

Active Publication Date: 2007-04-11
SHANGHAI HUAYI ENERGY CHEM
View PDF2 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The methyl iodide phase in which many impurities are dissolved is taken out as a low-boiling circulating liquid stream, but when the separation is stopped, a part of the liquid containing these impurities is added to the light removal tower as a reflux liquid, so these impurities are easily mixed into acetic acid
[0009] In addition, in the current purification process, in the delight phase step, I in the solution - The concentration is relatively high, and the conversion into methyl iodide is insufficient, which will pollute the logistics entering the dehydration tower, pollute the subsequent dehydration steps and heavy phase removal steps, and affect the purification effect
[0010] In addition, the current purification process is to discharge the material from the side line of the de-weighting tower, and the temperature of the discharge is 140°C, while the storage temperature of acetic acid is below 38°C, so the energy consumption required for cooling the product extracted from the side line is very high

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
  • Improved acetic acid purifying method
  • Improved acetic acid purifying method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment    Embodiment 1

[0066] Keep the composition in Table 1 in initial acetic acid 19, carry out experiment according to the flow process described in literature ("Acetic acid and its derivatives" in "Encyclopedia of Chemical Industry" (4th edition in 1991, second volume, page 719)) Fig. 1, measure The composition of each logistics.

[0067] Implementation steps: Methanol and CO are generated in a reactor under the action of a carbonylation catalyst to generate acetic acid. The reaction liquid containing catalyst and product is flash evaporated. The tail gas generated in the reaction zone is washed in the scrubbing system 6 to recover the catalyst. The initial acetic acid 19 produced by flash evaporation passes through the light removal tower 2 shown in "Fig. 1 process" to remove light components, and then draws wet acetic acid 21 from the side line of light removal tower 2, and wet acetic acid 21 removes water and other impurities in the dehydration tower 3 . Dried acetic acid is extracted fro...

Embodiment 2

[0071] Keep the composition in table 2 at initial acetic acid 19, technological process of the present invention and implementation step are tested, and absorbing liquid is from the shunting of the wet acetic acid 21 of light removal tower 2 bottom outlets, is about 3.5% of initial acetic acid 19. The composition of each stream was determined.

[0072] Implementation steps: Methanol and CO are generated in a reactor under the action of a carbonylation catalyst to generate acetic acid. The reaction liquid containing catalyst and product is flash evaporated. The tail gas generated in the reaction zone is washed in the scrubbing system 6 to recover the catalyst. The initial acetic acid 19 that flashing produces enters the bottom of multifunctional tower 8, keeps a certain amount of absorption liquid 41 at the top of tower, has a tower bottom reboiler 9 at the bottom of tower, keeps the part liquid vaporization of heating tower kettle, by controlling Heat is used to control the ...

Embodiment 3

[0076] The initial acetic acid 19 maintains the composition in Table 3, which is a flash product with lower water content compared with Table 1. The test is carried out according to the technical process of the present invention, see flow chart 2, and the absorption liquid comes from the bottom of light removal tower 2 The split flow of the wet acetic acid 21 of the outlet is about 4%wt of the initial acetic acid 19. The composition of each stream was determined.

[0077] composition

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 improved acetic acid purifying method includes available technological steps of eliminating light component, dewatering, and eliminating heavy component as well as increased absorption and steam stripping step before the step of eliminating light component. In the absorption and steam stripping step, the initial acetic acid product from flash evaporation and the added absorbing liquid are absorbed and steam stripped to form the gaseous material entering to the light component eliminating tower and liquid material returned to the reaction system. The corresponding apparatus includes one refining system comprising light component eliminating tower, dewatering tower, heavy component eliminating tower and waste acid tower; one gas scrubbing system; one decanter set in the top of the light component eliminating tower; and one increased multifunctional tower. The present invention has high acetic acid synthesizing reaction rate, less side products and lowered power consumption.

Description

technical field [0001] The present invention relates to a method for purifying acetic acid by carbonylation of methanol at low pressure, in particular to the improvement of the catalyst composition in the technology of carbonylation of low-pressure methanol to acetic acid towards high main catalyst concentration, high methyl iodide concentration, high methyl acetate concentration and low water concentration. acetic acid purification method. technical background [0002] Acetic acid is an important chemical intermediate and solvent for chemical reactions. Carbon monoxide and methanol are used as raw materials to produce acetic acid by oxo synthesis. Since Monsanto Corporation of the United States developed the production process of low-pressure methanol carbonylation of acetic acid, low-pressure methanol carbonylation of acetic acid technology has become the main method of producing acetic acid in the world. [0003] At present, the production process equipment of low-press...

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): C07C53/08C07C51/44
Inventor 陈大胜曹智龙刘艳吴文晶
Owner SHANGHAI HUAYI ENERGY CHEM
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com