Catalyst used in preparation of acrylic acid through one-step oxidation of propylene and preparation method thereof

A catalyst and acrylic acid technology, applied in physical/chemical process catalysts, chemical instruments and methods, chemical/physical processes, etc., can solve the problems of large catalyst particles, low solubility, poor catalyst repeatability, etc., to achieve fine and uniform particles and catalytic activity High and stable effect

Active Publication Date: 2013-09-11
SHENYANG INSTITUTE OF CHEMICAL TECHNOLOGY
View PDF7 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Heteropolyacids and their salts have high catalytic activity, but the preparation process of heteropolyacids and their salts is relatively complicated. When the reaction temperature of heteropolyacids and their salts is as high as 400 °C, the material structure collapses, and the catalyst loses its activity, which seriously reduces the catalytic activity of the catalyst. service life
In addition, the composite oxide catalysts used in the one-step oxidation of propylene to acrylic acid are often prepared by coprecipitation method, and the precursor salts of the catalyst need to be prepared into a mixed aqueous solution. Some elements such as Mo and V compounds have high solubility in water. , easy to form an aqueous solution; while other elements such as Te, Nb and other compounds have low solubility in water, "Top Catal" (2008, 50: 66-73), "Catalysis Today" (2010, 157: 33-38) and compounds such as Te and Nb involved in "Catal Lett" (2008, 126: 231-240), in order to make these compounds with low solubility also dissolve in water to form a uniform aqueous solution, a large amount of water needs to be used in the production process to Dissolution, resulting in the need for a large amount of energy to dry the solution or slurry containing the compound in the subsequent process, resulting in a great consumption of energy
In addition, the composite metal oxide catalyst prepared by co-precipitation method has relatively large particles with a specific surface area of ​​1m 2 / g~7 m 2 / g, the catalyst particles are large, and the catalyst is applied to the gas-solid phase reaction, and the gas and the catalyst cannot be in better contact, resulting in poor catalyst activity
European patents EP0608838 and EP0962253 have long reported Mo, V, Te, Nb composite metal oxide catalysts. This catalyst is prepared by co-precipitation method, and it is applied to the reaction of propane oxidation to prepare acrylic acid. The yield of acrylic acid is as high as 42%, but the patent JPA11226408, JPA10230164, and JPA11285636 also adopt the co-precipitation method to prepare composite metal oxide catalysts containing Mo, V, Te, and Nb, and apply it to the reaction of propane oxidation to prepare acrylic acid, but the yield of acrylic acid is between 10% and 21%. It can be seen that Mo, V, Te, Nb composite metal oxide catalysts are prepared by co-precipitation method, because of complex multi-component elements, multi-step preparation process and sensitivity of preparation parameters, the reproducibility of the prepared catalyst is poor. Method not conducive to industrial scale-up

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0017] 1. Preparation of catalyst:

[0018] Weigh 3.74 g of ammonium molybdate and 0.82 g of ammonium metavanadate and dissolve in 200 ml of deionized water at the same time, stir, and heat in a water bath at 70 ° C, the solution turns orange, then add 2.36 g of an aqueous solution of a compound containing tellurium, and continue stirring , heated in a water bath at 75 °C for 0.5 h to obtain a red solution A; weigh 15 g of citric acid and dissolve it in 150 ml of deionized water, stir, and dissolve fully to obtain a solution B; weigh 4 g of oxalic acid and dissolve it in 100 ml Heat and stir in deionized water. After the oxalic acid is completely dissolved, add 0.6 g of niobium hydroxide and continue to stir. After being completely dissolved, a colorless solution C is obtained; in a magnetic stirrer, add solutions B and C to solution A, After mixing evenly, adjust the pH of the solution to 2.2 with dilute nitric acid solution, heat in a water bath at 120 °C, heat and evaporate...

Embodiment 2

[0024] Weigh 5.62 g of ammonium molybdate, 1.23 g of ammonium metavanadate were dissolved in 300 ml of deionized water at the same time, stirred, heated in a water bath to 70 ° C, the solution turned orange, then added 2.45 g of an aqueous solution of a compound containing tellurium, at 75 Heat and stir at ℃ for 0.5 h to obtain a red solution A; add 0.4 mol / L niobium oxalate solution, an aqueous solution containing 10 g citric acid and 4.8 g silica sol with a mass fraction of 25% to the red solution, and mix well Use dilute nitric acid solution to adjust the pH of the solution to 1.8, heat in a water bath at 100 °C, heat and evaporate to form a sol, then move to 40 °C for aging to form a gel, and dry the obtained gel in a vacuum oven at 90 °C for 12 h. Then calcination was carried out. First, the temperature was raised to 260 °C at a heating rate of 10 °C / min, and the temperature was kept at 260 °C for 2 h, and then the temperature was raised to 500 °C at a heating rate of 10 °...

Embodiment 3

[0027] Weigh 3.74 g of ammonium molybdate and 0.64 g of ammonium metavanadate and dissolve in 100 ml of deionized water at the same time, stir, and heat in a water bath at 80 °C, the solution turns orange yellow, then add 2.45 g of an aqueous solution of a compound containing tellurium, at 75 Heat and stir at ℃ for 0.5 h to obtain red solution A; add 0.3 mol / L niobium oxalate solution, aqueous solution containing 10 g tartaric acid and 5.2 g aluminum sol with a mass fraction of 25% to the red solution, mix well and use Ammonia solution was used to adjust the pH of the solution to 3.6, heated in a water bath at 120 °C, heated to evaporate to form a sol, and then moved to 40 °C for aging to form a gel, and the obtained gel was dried in a vacuum oven at 90 °C for 12 h, and then Roasting, in a nitrogen atmosphere, the temperature was raised to 500 °C at a rate of 10 °C / min, and the temperature was kept at 500 °C for 2 h. The roasted catalyst was ground, pressed into tablets, and si...

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 provides a catalyst used in preparation of acrylic acid through one-step oxidation of propylene and a preparation method thereof, which relates to a catalyst and a preparation method thereof. A basic general formula of the catalyst is Mo1VaTebNbcAeBfO/yZ, wherein Mo is molybdenum, V is vanadium, Te is tellurium, Nb is niobium, A is at least one selected from the group consisting of phosphorus, boron, iron, tungsten and the like, B is at least one selected from the group consisting of potassium, cerium, caesium and the like, Z is SiO2 or Al2O3, a, b, c, d, e, f and y respectively represent mol ratios of every element, a is in a range of 0.2 to 0.6, b is in a range of 0.1 to 0.6, c is in a range of 0.01 to 0.2, d is in a range of 0.01 to 0.2, e is in a range of 0 to 0.05, f is in a range of 0 to 0.08, and y is in a range of 0 to 3. When the catalyst is applied to preparation of acrylic acid through one-step oxidation of propylene, the conversion rate of propylene is 78 to 92%, and selectivity of acrylic acid is 79 to 90%. The catalyst prepared by using the method has high activity, good selectivity and stable performance.

Description

technical field [0001] The invention relates to a catalyst and a preparation method thereof, in particular to a catalyst for the one-step oxidation of propylene to prepare acrylic acid and a preparation method thereof. Background technique [0002] Acrylic acid is an important organic chemical product. At present, it is usually produced by a two-step oxidation reaction of propylene, that is, propylene is first selectively oxidized to acrolein, and then oxidized to obtain acrylic acid. The two-step reaction of propylene to prepare acrylic acid is a mature process. The conversion rate of propylene and the yield of acrylic acid are also quite high, but the two-step process requires two different catalysts, two reactors and control systems, and the equipment investment is relatively high. However, the one-step oxidation of propylene to prepare acrylic acid has a simple process route and relatively low investment in equipment systems. In this reaction, the development of high-eff...

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): B01J27/057
Inventor 于三三李双明邵慧陈灿李文秀
Owner SHENYANG INSTITUTE OF CHEMICAL TECHNOLOGY
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap