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

Zirconium-molybdenum oxide catalyst for methane oxidation to synthesize formaldehyde and its preparation method

A methane oxidation and catalyst technology, applied in the chemical industry, can solve the problems of insufficient activity of lattice oxygen and high reaction temperature, and achieve the effects of good mechanical strength, simple preparation method, high selectivity and yield of formaldehyde

Inactive Publication Date: 2003-02-05
TSINGHUA UNIV
View PDF0 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This may be due to the fact that the active oxygen species of the catalyst, that is, lattice oxygen, is not active enough, and the catalyst needs a higher reaction temperature to activate methane, which easily leads to the deep oxidation of the reaction product formaldehyde to form carbon dioxide and carbon monoxide.

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] Calculate the required raw material ammonium molybdate ((NH 4 ) 6 Mo 7 o 24 4H 2 O, Tianjin Chemical Reagent Factory, the amount of analytically pure), be made into the ammonium molybdate aqueous solution that concentration is 0.13g / mL. Add 10.0mL of ammonium molybdate aqueous solution with a concentration of 0.13g / mL to 2.7g of zirconia powder with a particle size of 18nm, dry at 110°C for 8 hours, and bake at 600°C for 10 hours to make a catalyst (ZrO 2 ) 0.63 (Zr(MoO 4 ) 2 ) 0.36 (MoO 3 ) 0 . Zr(MoO 4 ) 2 The particle size is 35nm. Then, the catalyst was ground for 4 hours, pressed under 1.5MPa pressure, and sieved into 40-mesh particles for future use. The prepared catalyst is used in the selective oxidation of methane to formaldehyde. The reaction is carried out in a reaction gas ratio of CH 4 / O 2 / N 2 =10 / 1 / 3, space velocity 12000ml / (g.cat).h -1 , under the conditions of 5.0MPa pressure and 400°C reaction temperature. The catalyst consumption ...

Embodiment 2

[0019] Ammonium molybdate ((NH 4 ) 6 Mo 7 o 24 4H 2 O, Tianjin Chemical Reagent Factory, analytically pure) aqueous solution was added to 3.0 g of zirconia powders with a particle size of 16 nm, dried at 120° C. for 6 hours, and calcined at 550° C. for 11 hours to make a catalyst (ZrO 2 ) 0.74 (Zr(MoO 4 ) 2 ) 0.25 (MoO 3 ) 0.01 . Zr(MoO 4 ) 2 The particle size is 30nm. Then, the catalyst was ground for 4 hours, 180Kg / cm 2 Press to form and screen 30-mesh granules for future use. The prepared catalyst is used in the selective oxidation of methane to formaldehyde. The reaction is carried out in a reaction gas ratio of CH 4 / O 2 / N 2 =10 / 1 / 3, space velocity 12000ml / (g.cat).h -1 , a pressure of 5.0MPa, and a reaction temperature of 380°C. The catalyst consumption is 0.5g. Analysis of the reaction tail gas showed that the methane conversion rate was 3.3%, the formaldehyde selectivity was 53.8%, and the formaldehyde yield was 1.8%.

Embodiment 3

[0021] Ammonium molybdate ((NH 4 ) 6 Mo 7 o 24 4H 2 O, Tianjin Chemical Reagent Factory, analytically pure) aqueous solution joins 1.3g superfine zirconium dioxide (ZrO 2 ) powder, dried at 100°C for 9 hours, and calcined at 650°C for 9 hours to make a catalyst (ZrO 2 ) 0.38 (Zr(MoO 4 ) 2 ) 0.20 (MoO 3 ) 0.42 . Zr(MoO 4 ) 2 The particle size is 44nm. Then, the catalyst was ground for 5 hours, 190Kg / cm 2 Press to form and screen 20-mesh granules for future use. The prepared catalyst is used in the selective oxidation of methane to formaldehyde. The reaction is carried out in a reaction gas ratio of CH 4 / O 2 / N 2=10 / 1 / 3, space velocity 12000ml / (g.cat).h -1 , under the conditions of 5.0MPa pressure and 400°C reaction temperature. Catalyst consumption 0.5g. Analysis of the reaction tail gas showed that the methane conversion rate was 7.0%, the formaldehyde selectivity was 36.0%, and the formaldehyde yield was 2.5%.

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

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Login to View More

Abstract

The molecular formula of zirconium-molybdenum oxide catalyst for synthesizing formaldehyde by means of methane oxidation is (ZrO2)x(Zr(MoO4)2)y (MoO3)z, and its preparalcon method includes the following steps: using zirconium dioxide powder ammonium molbdate powder as raw material, metering and weighing ammonium molybdate powder according to the above-mentioned molecular formula, using deionized water to prepare ammonium modybdate aqueous solution with a certain concentration, adding said aqueous solution into zirconium dioxide powder, drying the mixture, high-temp. roasting, mechanical grinding, press-forming, screening granules so as to obtain the catalyst.

Description

technical field [0001] The invention relates to a zirconium molybdenum oxide catalyst for methane oxidation to formaldehyde and a preparation method thereof, belonging to the chemical industry [0002] technology field. Background technique [0003] Natural gas contains a large amount of methane (about 90-100%). On a global scale, the proven reserves of natural gas are greater than those of oil; compared with coal, natural gas is less polluted. Therefore, natural gas is a clean fuel and chemical raw material. Using natural gas as raw material to produce formaldehyde and other basic chemical products can bring huge economic benefits. This is one of the most attractive potential applications for natural gas (methane). [0004] For decades, research work on catalysts for the selective oxidation of methane to formaldehyde has been extensively carried out worldwide. A.de.Lucas et al. reported on Applied Catalysis A General.172 (1998) 165 that W / HZSM-5 was used as catalyst at...

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): B01J23/28
Inventor 张昕贺德华张启俭朱起明
Owner TSINGHUA UNIV