CN1146370A - Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere - Google Patents
Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere Download PDFInfo
- Publication number
- CN1146370A CN1146370A CN 95112027 CN95112027A CN1146370A CN 1146370 A CN1146370 A CN 1146370A CN 95112027 CN95112027 CN 95112027 CN 95112027 A CN95112027 A CN 95112027A CN 1146370 A CN1146370 A CN 1146370A
- Authority
- CN
- China
- Prior art keywords
- catalyst
- molecular sieve
- methane
- indium
- reducing nitrogen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02C20/00—Capture or disposal of greenhouse gases
- Y02C20/20—Capture or disposal of greenhouse gases of methane
Landscapes
- Catalysts (AREA)
Abstract
The characteristic lies in that the active component of said catalyst is indium carried on the natural or artificially synthesized molecular sieve, the Si an Al ratio of the molecular sieve is no less than 10, the weight percentage of indium carried by the molecular sieve is 0.5-20%. Said invention uses only methane as reductant, indium as active component of the catalyst, the reactivity is excellent in very wide range of temperature, the percent conversion of nitrogen oxygen compound can reach to above 90%.
Description
The present invention relates to oxynitrides (NO in the oxygen-enriched combusting product
x) the catalytic eliminating technology, particularly with methane (CH
4) employed catalyst, preparation method and catalytic process during as reducing agent.
Oxynitrides (NO
x, i.e. NO and NO
2, wherein mainly be NO) and be considered to relevant with some other to the environmental problem that the mankind are harmful to city fog, acid rain, at the NO of all dischargings
xIn 55% product from the fuel combustion of gas fired-boiler, Industrial Boiler, steam turbine and stationary source engine is arranged approximately.NH under the oxidizing atmosphere
3Select Reduction of NO
x(SCR) be acknowledged as now and from industrial waste gas, remove NO
xEffective method is in Japan and the industrialization of some western countries.But NH
3Leak easily and cause secondary pollution, course of reaction also is attended by SO
2By V
2O
5Be oxidized to SO
3Then generate NH
4HSO
4(NH
4)
2S
2O
7Thereby cause pipe reactor corrosion and obstruction and catalysqt deactivation.Because the problems referred to above and NH
3Expensive equipment and operating cost such as storage, transportation and use, be necessary to explore one without NH
3Make the processing method of reducing agent.Nineteen nineties such as Iwamoto, the molecular sieve with Cu ion-exchange was catalyst, used H
2, CO
2, ethene, propylene, propane are the reducing agent reductive NO, find along with oxygen content increases N
2Generating rate increases.But Iwamoto avowed once that under the situation that aerobic exists, when making catalyst with Cu-ZSM-5, methane was not NO
xEffective reducing agent.U. S. application number has been pointed out an effectively catalyst system for the patent of No.5149112, is reducing agent with an amount of methane under oxygen-containing atmosphere, with the sieve peg-raking catalyst of metal ion exchanged, these metals are Co, Ni.Fe.Cr, Rh and Mn, wherein active best with Co-ZSM-5.Because the extensive use of natural gas in industrial production, so the oxynitrides that combustion process gave off of selecting catalytic reduction plant gas, Industrial Boiler, steam turbine etc. with methane is a practicality and cheap approach.JP06,262,039 proposes under indium (In) catalyst action that ZSM5 molecular sieve or ferrierite support, and when aerobic existed, reducing agent methane and carbon monoxide acted on simultaneously, can remove oxynitrides effectively, JP06,132,139 propose ZSM5 molecular sieve supported be under the indium catalyst action of auxiliary agent with alkali metal, when aerobic existed, reducing agent methane can remove oxynitrides effectively.
The object of the present invention is to provide a kind of alkali metal containing or alkaline-earth metal, the preparation method is simple, under a large amount of oxygen existence conditions, only comes the catalyst of selective reduction oxynitrides with methane.
The invention provides a kind of catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere, it is characterized in that: this activity of such catalysts component is an indium, be supported on the natural or artificial synthesis of molecular sieve, the silica alumina ratio of molecular sieve is more than or equal to 10, and the weight percentage of molecular sieve supported indium is 0.5-20%.
Catalyst provided by the invention can be by the indium salt (In (NO with solubility
3) or InCl
3) adopt immersion process for preparing with molecular sieve, perhaps pass through In
2O
3Prepare (with In with the molecular sieve mechanical mixture
2O
3+ HZSM5 represents); Bake out temperature 60-100 ℃, sintering temperature 500-1000 ℃.Catalyst provided by the present invention removes in the reaction at oxynitrides and uses, and is reducing agent with methane only, [CH
4]/[NO] concentration ratio is 0.2-8.0, reaction temperature is between 300-700 ℃, the unstripped gas air speed is 1000h
-1-100000h
-1Reaction temperature the best is between 350-550 ℃.The present invention is a reducing agent with methane only, is the activity of such catalysts component with the indium only, and good in very wide temperature range internal reaction activity, the oxynitrides conversion ratio can reach more than 90%.Method for preparing catalyst provided by the present invention is simple, and reaction has the good high-temperature reactivity to selectively reducing nitrogen oxides by methane, helps technology and amplifies, and the commercial Application that removes reaction for oxynitrides has bigger Practical significance.Below by example in detail the present invention is described in detail.
Example 1. Preparation of catalysts: be the preparation that example is described catalyst system therefor among the present invention prevailingly only here with the In/HZSM5 (silica alumina ratio is 25) that contains indium 10% (weight percentage).The HZSM5 molecular sieve is provided by Catalyst Factory, Nankai Univ, with 0.7391 gram indium nitrate crystal (In (NO
3)
34.5H
2O) be dissolved in 2 ml deionized water, add 2.0 gram HZSM5 (silica alumina ratio is 25) again, left standstill 24 hours after fully stirring, 80 ℃ were dried by the fire 2 hours, place 700 ℃ of roastings of Muffle furnace 4 hours, before the reaction, with the catalyst compressing tablet, break that to sieve out 30-60 purpose particle standby into pieces.
Methane selective reduction nitric oxide under example 2. oxidizing atmospheres: be that example is described activity of such catalysts test among the present invention prevailingly only here with the In/HZSM5 (silica alumina ratio is 25) that contains indium 10% (weight percentage).Active testing carries out in fixed bed reactors.Before advancing reactor, nitric oxide, methane, oxygen and helium fully mix in blender, catalyst amount 0.5 gram in the active testing, and unstripped gas air speed (GHSV) is 3600h
-1, reaction pressure is a normal pressure, and reactor places in the temperature control electric furnace, and reaction temperature 300-700 ℃, with online chromatography analysis product, catalyst activity is a standard with the conversion ratio (%) that nitric oxide is converted into nitrogen.
The reactivity catalyst of example 3 different catalysts
*Reaction temperature/℃
300 350 400 450 500 550 600 650 700H-ZSM5 9.8 17.2 26.2 31.7 27.9 30.1 32.1Co/HZSM5 12.5 30.4 51.3 65.3 49.1 35.9Ni/HZSM5 9.5 20.7 32.0 49.9 60.8 52.8 46.2 40.1 26.8Cu/HZSM5 0 10.0 15.9 14.9 13.3 17.2 16.2 16.2 19.5Zn/HZSM5 11.8 16.6 25.9 37.5 47.4 49.4 44.2 20.9 29.2Ga/HZSM5 0 16.9 33.1 49.0 63.0 64.1 62.0 58.3 49.8In/HZSM5 20.8 51.8 77.8 84.9 77.1 63.3 54.8 47.7In/HY
*9.8 9.7 6.6 7.6 11.7 12.0 13.5 20.4 22.8In
2O
5+ 11.6 33.4 49.2 57.3 63.1 64.6 47.3 30.2 29.3HZSM5
* *The metal ion weight percentage is 3.0%
*In%=10%, GHSV=3600h
-1, NO=2500ppm, CH
4=2000ppm, O
2=2%, He is a balance gas, catalyst loading amount 1.0ml, and reaction pressure is a normal pressure.
The content of example 4. indium metal to the reactivity of In/HZSM5 catalyst influence catalyst reaction temperatures/℃
300 350 400 450 500 550 600 650HZSM5,9.8 17.2 26.2 31.7 27.9 30.1 32.11%In/HZSM5,19.2 38.1 70.2 77.1 66.2 55.0 41.4 31.13%In/HZSM5,20.8 51.8 77.8 84.9 77.1 63.3 54.8 47.75%In/HZSM5,38.4 71.3 84.3 92.1 87.9 77.2 62.810%In/HZSM5,26.4 70.1 92.1 92.3 89.8 79.7 67.020%In/HZSM5,0 42.9 71.5 81.6 81.0 78.4 78.1 55.7 catalyst loading amount 1.0ml; Reaction pressure is normal pressure, GHSV=3600h-1NO=2500ppm, CH
4=2000ppm, O
2=2%, He is a balance gas
Silica alumina ratio (the SiO of example 5 molecular sieves
2/ Al
2O
3) to 10%In/HZSM5
The reactivity of catalyst influence catalyst reaction temperatures/℃
300 350 400 450 500 550 600 650In/HZSM5 (25)
*26.4 70.1 92.1 92.3 89.8 79.9 67.0In/HZSM5 (38) 9.3 32.1 69.1 79.3 73.6 73.6 68.7 55.5In/HZSM5 (50) 5.9 48.5 79.1 85.2 88.7 73.1 68.6 53.7In/HZSM5 (58) 11.5 32.7 68.3 72.2 77.0 73.4 65.2 47.7
*Numerical table in the bracket shows silica alumina ratio.Catalyst loading amount 1.0ml, reaction pressure is normal pressure .GHSV=3600h
-1NO=2500ppm, CH
4=2000ppm, O
2=2%, He is that balance gas example 6 reaction temperatures are to NO+CH
4+ O
210%In/HZSM5 (silica alumina ratio is 25)
The catalyst reaction activity influence reaction temperature/℃ 375 400 425 450 475 500NO conversion ratios (%), 80.5 83.7 92.0 96.1 96.5 89.2 catalyst loading amount 1.0ml, reaction pressure is a normal pressure, GHSV=3600h
-1, NO=2500ppm, CH
4=2000ppm, O
2=2%, He is a balance gas.Example 7 unstripped gas air speeds are to 10%In/HZSM5 (Si/Al=25) catalyst
Reactivity influence air speed GHSV (h
-1) 300 350 400 450 500 550 600 6503600 (a) 26.4 70.1 92.1 92.3 89.8 79.9 67.07200 (b) 15.4 62.7 77.7 77.6 72.9 62.1 47.228800 (c), 0 21.5 39.0 61.0 58.6 55.8 56.2 34.8 catalyst loading amounts: (a) (b) 1.0ml, (c) 0.5ml, reaction pressure is a normal pressure, NO=2500ppm, CH
4=2000ppm, O
2=2%, He is a balance gas, example 8[CH
4]/[NO] comparison 5%In/HZSM5 goes up the influence [CH that NO transforms
4] (ppm) [NO] (ppm) [CH
4]/[NO] NO conversion ratio (%)
1000 2500 0.4 80.5
2000 2500 0.8 ks?96.1
2000 2000 1.0 98.6
3,000 1,500 2.0 100 catalyst: 5%In/HZSM5,450 ℃ of reaction temperatures, reaction pressure are normal pressure, catalyst loading amount 1.0ml, GHSV=3600h
-1, [O
2]=2.0%, He are balance gas example 9[O
2]/[CH
4] comparison 5%In/HZSM5 goes up the influence [O of NO conversion ratio
2] (%) [CH
4] (%) [NO] (%) [O
2]/[CH4] [CH
4]/[NO] 450 ℃ of NO conversion ratio (%) 4.0 0.1 0.125 40 0.8 100 2.0 0.2 0.25 10 0.8 96.1 1.0 0.2 0.25 5 0.8 85.4 0.5 0.2 0.25 2 0.8 84.9 0 0.2 0.25 0 0.8 49.0 reaction temperatures, reaction pressure is a normal pressure, catalyst loading amount 1.0ml, He is a balance gas, GHSV=3600h
-1
Claims (4)
1. catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere, it is characterized in that: this activity of such catalysts component is an indium, be supported on the natural or artificial synthesis of molecular sieve, the silica alumina ratio of molecular sieve is more than or equal to 10, and the weight percentage of molecular sieve supported indium is 0.5-20%.
2. the described selectively reducing nitrogen oxides by methane Preparation of catalysts of claim 1 method is characterized in that: catalyst can be by with indium salt and molecular sieve employing immersion process for preparing, and indium salt is In (NO
3)
3Or InCl
3, also can pass through In
2O
3Prepare with the molecular sieve mechanical mixture; Sintering temperature 500-1000 ℃.
3. the method for a methane selective reducing nitrogen-oxygen compound under oxidation atmosphere is characterized in that: using the described catalyst of claim 1, is reducing agent with methane only, [CH
4]/[NO] concentration ratio is 0.2-8.0, reaction temperature is between 300-700 ℃, the unstripped gas air speed is 1000h
-1-100000h
-1
4. by the method for the described methane selective reducing nitrogen-oxygen compound under oxidation atmosphere of claim 3, it is characterized in that: optimal reaction temperature is at 350-550 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 95112027 CN1146370A (en) | 1995-09-27 | 1995-09-27 | Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 95112027 CN1146370A (en) | 1995-09-27 | 1995-09-27 | Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1146370A true CN1146370A (en) | 1997-04-02 |
Family
ID=5079251
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 95112027 Pending CN1146370A (en) | 1995-09-27 | 1995-09-27 | Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1146370A (en) |
-
1995
- 1995-09-27 CN CN 95112027 patent/CN1146370A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5580534A (en) | Zeolite-spinel catalyst for the reduction of nitrogen oxides and the process thereof | |
| Iwamoto et al. | Selective catalytic reduction of NO by hydrocarbon in oxidizing atmosphere | |
| EP0709129A1 (en) | Method of reducing NOx emissions from lean-burn combustion engines | |
| EP0738179A1 (en) | A process for treating nitrogen oxide-containing gas using a cerium zeolite | |
| EP0499286B1 (en) | Catalyst for and method of purifying exhaust gas | |
| EP0781592A1 (en) | Exhaust gas purification method by reduction of nitrogen oxides | |
| US3032387A (en) | Selective removal of nitrogen oxides from gas streams | |
| CN1146370A (en) | Catalyst for methane selective reducing nitrogen-oxygen compound under oxidation atmosphere | |
| US5364606A (en) | NOx reduction through the use of methane | |
| CN100391580C (en) | Catalyst capable of reducing nitric oxides and eliminating soot particle simultaneously and application thereof | |
| CN1142025C (en) | Methane selective reducing nitrogen oxide catalyst under oxygen-enriched condition | |
| CN115999543A (en) | Multi-shell structure CO-SCR denitration catalyst and preparation method thereof | |
| CN1095402C (en) | Catalyst for eliminating nitrogen oxide by means of microwave catalysis | |
| CN1246070C (en) | Rarefied-burning automobile exhaust gas catalyzing and purifying method and apparatus | |
| JP2851444B2 (en) | Exhaust gas purification method | |
| JP3143936B2 (en) | Exhaust gas purification catalyst and exhaust gas purification method | |
| CN111921556A (en) | Composite molecular sieve catalyst for NO decomposition and denitration, and preparation method and application thereof | |
| CN1413765A (en) | Catalyst of ammonia selective reducing nitrogen oxide | |
| CN110694470A (en) | System and method for flue gas desulfurization and denitration by using methane | |
| KR100486069B1 (en) | Catalyst for removal of nitrogen oxide and carbon monooxide and purifying method using ethanol as a reductant over the same | |
| KR100408511B1 (en) | Catalyst for purifying exhaust gas of automobile and method for manufacturing the same | |
| CN1062240C (en) | Method for preparing synthetic gas by catalyze and oxidize | |
| CN107349952A (en) | A kind of preparation method of N doping ternary metal oxide catalyst | |
| JP3579745B2 (en) | Exhaust gas purification method | |
| CN1223902A (en) | Catalyst for selective catalytic reduction of nitrogen oxide using methane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C01 | Deemed withdrawal of patent application (patent law 1993) | ||
| WD01 | Invention patent application deemed withdrawn after publication |