CN1616150A - Methane oxygen-free aromatization catalyst and preparing method and use - Google Patents
Methane oxygen-free aromatization catalyst and preparing method and use Download PDFInfo
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- CN1616150A CN1616150A CNA2003101156216A CN200310115621A CN1616150A CN 1616150 A CN1616150 A CN 1616150A CN A2003101156216 A CNA2003101156216 A CN A2003101156216A CN 200310115621 A CN200310115621 A CN 200310115621A CN 1616150 A CN1616150 A CN 1616150A
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Abstract
The oxygen-free methane aromatizing catalyst with high activity and high stability has zeolite molecular sieve as carrier, active component of VIB transition metal element in the content of 1-10 wt%. The preparation process includes the following steps: exchanging molecular sieve powder into ammonium type molecular sieve, drying and roasting to obtain hydrogen type molecular sieve; soaking the molecular sieve with fluorine containing compound solution to modify and denature, drying and roasting to obtain fluorine modified molecular sieve; and soaking the modified molecular sieve in the solution containing VIB transition metal element, drying and roasting to obtain the catalyst of the present invention.
Description
Technical field
The present invention relates to a kind of catalyzer, relate in particular to a kind of methane non oxidative aromatization catalyzer.
The invention still further relates to above-mentioned Preparation of catalysts method.
The invention still further relates to the application of above-mentioned catalyzer in oxygen-free aromatization reaction of methane.
Background technology
Sweet natural gas is because its abundant reserves, in today that global oil reduces day by day, become and is hopeful to substitute oil and becomes one of energy of the energy of future generation.But Sweet natural gas is a gas at normal temperatures and pressures, and with respect to oil, the energy resource density of Sweet natural gas is lower, and difficult transportation and storage, causes the conversion of present Sweet natural gas and utilization to be very restricted.The challenge that today, energy industry faced is: seek that a kind of production is more favourable, economical to environment, the effective ways of transportable fuel, so the key issue of the conversion of Sweet natural gas and utilization is to be the more liquid petroleum chemical intermediate of high added value that has that easier storage and transportation are arranged with conversion of natural gas.
Natural main component is a methane, conversion of Sweet natural gas and methane at present and utilization mainly can be divided into direct conversion and two kinds of approach of indirect reformer: direct path for transformation such as methane oxidation coupling system ethene, methane selective oxidation making methyl alcohol and formaldehyde, methane non oxidative aromatization system aromatic hydrocarbons and hydrogen etc.: indirect reformer is to be synthetic gas with methane conversion, again by synthetic gas preparing liquid fuel and a series of important chemical productss such as methyl alcohol, acetate.Oxygen-free aromatization reaction of methane as a kind of under the condition of anaerobic, be the approach of useful industrial chemicals such as benzene, naphthalene, ethene and hydrogen directly with methane conversion, since 1993 are found, become methane conversion and the focus that utilizes the field rapidly, caused increasing attention.
Oxygen-free aromatization reaction of methane is under the molecular sieve catalyst that utilizes transition metal oxide to modify under the mobile atmosphere is having the condition of oxygen methane conversion not to be useful industrial chemicals such as benzene, naphthalene, ethene and hydrogen.The catalyzer of initial report is that molybdenum oxide is supported on the dual-function catalyst on the HZSM-5 molecular sieve, by the interaction between transition metal oxide and molecular sieve carrier, reaches activation methane and has obtained having better active catalyzer.Aspect screening of catalyst, done at present a large amount of work, except the good molecular sieve carrier ZSM-5 (CN1167653) of initial discovery, found that also other has the molecular sieve MCM-22 (CN1271622) of good catalytic and stability, ZSM-11 (CN1262968), ZRP-1 (CN1174757) etc.Mo/HZSM-5 is as a kind of molecular sieve supported dual-function catalyst, the interpolation of second component also can produce very big influence to the performance of catalyzer, discover in the Mo/HZSM-5 dual-function catalyst add second component such as Ru, Pt, W, Zr, Co, Fe and Cr can improve activity of such catalysts and (or) stability, but play opposite effect yet add elements such as V, Li, P.
Problem the most serious of oxygen-free aromatization reaction of methane is that carbon deposit seriously causes rapid catalyst deactivation because reaction is at high temperature carried out.Discover that under 973K and 1atm, nearly 20-40% is converted into the surface that carbon deposit covers catalyzer in the methane of conversion, greatly reduces the selectivity of useful products such as aromatic hydrocarbon.The carbon deposit that generates in the reaction process not only can cover the acidic site of molecular sieve simultaneously, and can stop up the pore passage structure of molecular sieve, so the life of catalyst of oxygen-free aromatization reaction of methane is all shorter.Carbon deposit is the major cause of catalyst deactivation, so the carbon deposit in the inhibited reaction process not only can improve reactive activity, but also can improve the selectivity of useful products such as aromatic hydrocarbons in the reaction product.By in unstripped gas, adding a spot of CO, CO
2Or O: can play the carbon deposit in the inhibited reaction, improve the effect of the stability of catalyzer.Molecular sieve is as the carrier of catalyzer, and its acidity and pore passage structure also have very big influence to reactivity worth.By molecular sieve is carried out the acidity that dealuminzation is regulated molecular sieve under the hydrothermal condition, the molecular sieve after the modification shows better anti-carbon deposition ability as the carrier of catalyzer as a result, and the stability of catalyzer and the yield of aromatic hydrocarbons are improved simultaneously.The HZSM-5 molecular sieve of alkaline purification can generate the central hole structure between brilliant crack, thereby make the stability of molecular sieve be greatly improved substantially not on the basis of saboteur's sieve skeleton shelf structure, has improved the stability of catalyzer simultaneously greatly.
The fluorine modification is a kind of method that caused the enhancing acidic zeolite of a lot of concerns in the last few years, because the strong electrophilic effect of fluorine can strengthen the acidity of molecular sieve B acid greatly, thereby improves the stability of molecular sieve catalyst.Utilize acidity that fluorine modification Song strengthens the ZSM-5 molecular sieve in the reaction of synthesize methyl tert-butyl ether, to obtain application, by dipping and activation step subsequently, can be so that activity be greatly improved.The acidity of utilizing the method for fluorine modification to modify the molecular sieve carrier of oxygen-free aromatization reaction of methane dual-function catalyst, catalyzer after the discovery modification is compared with unmodified catalyzer, not only improved the activity of aromatization greatly, and make the stability of catalyzer also be greatly improved, obtained higher aromatics yield.Thereby improved the utilization ratio of methane.
Summary of the invention
The purpose of this invention is to provide a kind of modification methane non oxidative aromatization catalyzer.
Another object of the present invention provides above-mentioned Preparation of catalysts method.
Methane non oxidative aromatization catalyzer provided by the invention is made of jointly carrier and active ingredient, and carrier is an activated molecular sieve in oxygen-free aromatization reaction of methane, as ZSM-5, MCM-22, ZRP-1, ZSM-11 etc.Active ingredient is the group vib transition metal, as wherein one or more such as chromium, molybdenum, tungsten, and preferred molybdenum, the content of active ingredient is 1～10%.
The method of the above-mentioned catalyzer of preparation provided by the invention, key step is:
A) molecular screen primary powder is exchanged for ammonium type molecular sieve, after the 80-120 ℃ of drying, 200-600 ℃ roasting 2-10 hour hydrogen type molecular sieve;
B) compound (as fluorine-containing compounds such as Neutral ammonium fluoride, hydrofluoric acid, aluminum trifluoride or trifluoromethanes) with fluorine is dissolved in the solution that solvent forms fluorochemicals, and the molecular sieve that step a is made mixes with solution then, and 60-140 ℃ flooded 10-24 hour;
C) molecular sieve that step b is made is in 30-100 ℃ of dry 1-10 hour, and 200-600 ℃ of calcination activation obtains the molecular sieve of fluorine modification;
D) with the molecular sieve of solution impregnation step c gained that contains the group vib transition element, 60-140 ℃ of dipping 10-24 hour, after the 80-120 ℃ of drying, 200-600 ℃ roasting 2-10 hour the methane non oxidative aromatization catalyzer.
Can be used as carrier through the molecular sieve of the modification of above-mentioned preparation and be used for the methane non oxidative aromatization Preparation of catalysts.
Embodiment
Be described in detail the comparative result of the present invention and original technical result below by embodiment and comparative example, but the present invention is not subjected to the restriction of the following example.
Embodiment 1
The preparation of modified catalyst:
1, the former powder of sodium type NaZSM-5 molecular sieve catalytic agent carrier exchanges 10 hours by the ammonium nitrate solution that utilizes 1M and can be exchanged for ammonium type ZSM-5 molecular sieve under 353K, obtains Hydrogen HZSM-5 molecular sieve carrier in 5 hours 500 ℃ of following roastings then.
2, adding concentration in the 10.0g HZSM-5 molecular sieve is 2.0 * 10
-3Mol
-4The 17ml Neutral ammonium fluoride the aqueous solution and stir, so in 120 ℃ of following dried overnight, dry good molecular sieve obtained the HZSM-5 molecular sieve of activatory fluorine modification earlier in 5 hours then in 4 hours 350 ℃ of roastings 250 ℃ of roastings.
3, the carrier after a certain amount of modification places the dipping bottle, the ammonium molybdate solution and the carrier that prepare the molybdenum that is equivalent to 6%Mo content are stirred, dry under 120 ℃ behind the room temperature dipping certain hour, dried catalyst precursor made the Mo/HZSM-5 catalyzer of fluorine modification in 6 hours 500 ℃ of roastings.
Embodiment 2
The preparation of modified catalyst:
1, the former powder of support of the catalyst is exchanged for ammonium type molecular sieve by ammonium, obtains Hydrogen HZSM-5 molecular sieve carrier in 5 hours 500 ℃ of following roastings then.
2, adding concentration in the 10.0g HZSM-5 molecular sieve is 2.0 * 10
-3Mol
-4The 17ml Neutral ammonium fluoride the aqueous solution and stir, so in 120 ℃ of following dried overnight, dry good molecular sieve obtained the HZSM-5 molecular sieve of activatory fluorine modification earlier in 5 hours then in 4 hours 350 ℃ of roastings 250 ℃ of roastings.
3, the carrier after a certain amount of modification places the dipping bottle, the ammonium molybdate solution and the carrier that prepare the molybdenum that is equivalent to 6%Mo content are stirred, dry under 120 ℃ behind the room temperature dipping certain hour, dried catalyst precursor made the Mo/HZSM-5 catalyzer of fluorine modification in 6 hours 500 ℃ of roastings.
Comparative example 1
Conventional Mo/HZSM-5 Preparation of catalysts process:
The HZSM-5 molecular sieve carrier of a certain amount of routine places the dipping bottle, the ammonium molybdate solution and the carrier that prepare the molybdenum that is equivalent to 6%Mo content are stirred, in 1200 ℃ of dryings, dried catalyst precursor made conventional Mo/HZSM-5 catalyzer in 6 hours 500 ℃ of roastings behind the room temperature dipping certain hour.
Embodiment 3
Oxygen-free aromatization reaction of methane is to carry out in the fixed-bed reactor of continuously feeding, and the internal diameter of quartz reactor is 8mm, and the loading amount of catalyzer is 0.58, and catalyzer is at first handled half an hour with rare gas element He down at 600 ℃, switches to CH then
4-N
2Mixing raw material gas react N at 700 ℃
2Volumn concentration be 9.5%.The air speed of methane is 1500ml/g.h, and pressure is 1atm.Reaction product is carried out on-line analysis in 0V-101 and HayeSep D chromatographic column enter the Varian chromatogram of equipment thermal conductivity detector, adopt N
2The composition that comprises the product of carbon deposit as interior mark analysis.
The methane non oxidative aromatization performance of Mo/HZSM-5 catalyzer after table 1 modification
| Reaction times methane conversion aromatics yield (min) is (mol%) (mol%) |
| ????90??????????15.0??????????11.4 ????150?????????12.9??????????10.8 ????210?????????12.3??????????10.5 ????270?????????11.7??????????10.2 ????330?????????11.5??????????9.9 ????390?????????11.2??????????9.8 ????450?????????10.9??????????9.5 ????510?????????10.7??????????9.4 ????570?????????10.4??????????9.2 |
Embodiment 4
Oxygen-free aromatization reaction of methane is to carry out in the fixed-bed reactor of continuously feeding, and the internal diameter of quartz reactor is 8mm, and the loading amount of catalyzer is 0.5g, and catalyzer is at first handled half an hour with rare gas element He down at 600 ℃, switches to CH then
4-N
2Mixing raw material gas under 700 ℃, react N
2Volumn concentration be 9.5%.The air speed of methane is 1500ml/g.h, and pressure is 1atm.Reaction product is carried out on-line analysis in 0V-101 and HayeSep D chromatographic column enter the Varian chromatogram of equipment thermal conductivity detector, adopt N
2The composition that comprises the product of carbon deposit as interior mark analysis.
The methane non oxidative aromatization performance of Mo/HZSM-5 catalyzer after table 2 modification
| Reaction times methane conversion aromatics yield (min) is (mol%) (mol%) |
| ????90??????????13.6???????????11.1 ????150?????????12.6???????????10.6 ????210?????????11.9???????????10.2 ????270?????????11.4???????????10.0 ????330?????????11.3???????????9.7 ????390?????????10.9???????????9.5 ????450?????????10.5???????????9.3 ????510?????????10.4???????????9.2 ????570?????????10.2???????????9.0 |
Comparative example 2
Oxygen-free aromatization reaction of methane is to carry out in the fixed-bed reactor of continuously feeding, and the internal diameter of quartz reactor is 8mm, and the loading amount of catalyzer is 0.5g, and catalyzer is at first handled half an hour with rare gas element He down at 600 ℃, switches to CH then
4-N
2Mixing raw material gas under 700 ℃, react N
2Volumn concentration be 9.5%.The air speed of methane is 1500ml/g.h, and pressure is 1atm.Reaction product is carried out on-line analysis in OV-101 and HayeSep D chromatographic column enter the Varian chromatogram of equipment thermal conductivity detector, adopt N
2The composition that comprises the product of carbon deposit as interior mark analysis.
The methane non oxidative aromatization performance of the conventional Mo/HZSM-5 catalyzer of table 3
| Reaction times methane conversion aromatics yield (min) is (mol%) (mol%) |
| ????90???????????13.5??????????10.6 ????150??????????12.2??????????9.9 ????210??????????11.4??????????9.6 ????270??????????10.4??????????9.2 ????330??????????10.4??????????8.8 ????390??????????10.2??????????8.6 ????450??????????10.0??????????8.2 ????510??????????9.5???????????8.1 ????570??????????9.1???????????7.8 |
Claims (5)
1, a kind of methane non oxidative aromatization catalyzer is made of jointly carrier and active ingredient, and carrier is an activated molecular sieve in oxygen-free aromatization reaction of methane, and active ingredient is one or more in the group vib transition metal, and the content of active ingredient is 1～10%;
Described molecular sieve is ZSM-5, MCM-22, ZRP-1, ZSM-11;
Described transition metal is that chromium, molybdenum are or/and tungsten.
2, by the described catalyzer of claim 1, it is characterized in that: activeconstituents is a molybdenum.
3, a kind of method for preparing the described catalyzer of claim 1, preparation process is:
A) molecular screen primary powder is exchanged for ammonium type molecular sieve, after the 80-120 ℃ of drying, 200-600 ℃ roasting 2-10 hour hydrogen type molecular sieve;
B) compound with fluorine is dissolved in the solution that solvent forms fluorochemicals, and the molecular sieve that step a is made mixes with solution then, and 60-140 ℃ flooded 10-24 hour;
C) molecular sieve that step b is made is in 30-100 ℃ of dry 1-10 hour, and 200-600 ℃ of calcination activation obtains the molecular sieve of fluorine modification;
D) with the molecular sieve of solution impregnation step c gained that contains the group vib transition element, 60-140 ℃ of dipping 10-24 hour, after the 80-120 ℃ of drying, 200-600 ℃ roasting 2-10 hour the methane non oxidative aromatization catalyzer.
4, by the described preparation method of claim 3, it is characterized in that: the compound of described fluorine is fluorine-containing compounds such as Neutral ammonium fluoride, hydrofluoric acid, aluminum trifluoride or trifluoromethane.
5, as the application of the described catalyzer of above-mentioned each claim in oxygen-free aromatization reaction of methane.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103418429A (en) * | 2012-05-16 | 2013-12-04 | 中国石油化工股份有限公司 | Methane oxygen-free dehydrogenation aromatization catalyst and preparation method thereof |
| CN107500312A (en) * | 2017-08-10 | 2017-12-22 | 河南师范大学 | A kind of fluorine richness molecular sieve H ZSM 35 and preparation method thereof |
| CN109420517A (en) * | 2017-08-30 | 2019-03-05 | 北京化工大学 | A kind of method that methane low temperature conversion prepares higher hydrocarbon |
| CN111298829A (en) * | 2020-04-03 | 2020-06-19 | 大连理工大学 | Preparation method and application of catalyst with strong anti-carbon performance in reaction for preparing aromatic hydrocarbon from methane in oxygen-free mode |
| CN112044457A (en) * | 2020-08-14 | 2020-12-08 | 北京航天试验技术研究所 | Supported orthohydrogen conversion catalyst and preparation method thereof |
| CN112221538A (en) * | 2020-10-12 | 2021-01-15 | 南京理工大学 | Preparation method of fluoroalkyl modified cellulose supported palladium catalyst |
-
2003
- 2003-11-10 CN CNA2003101156216A patent/CN1616150A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103418429A (en) * | 2012-05-16 | 2013-12-04 | 中国石油化工股份有限公司 | Methane oxygen-free dehydrogenation aromatization catalyst and preparation method thereof |
| CN103418429B (en) * | 2012-05-16 | 2016-02-10 | 中国石油化工股份有限公司 | Oxygen-free dehydrogenating aromatization of methane Catalysts and its preparation method |
| CN107500312A (en) * | 2017-08-10 | 2017-12-22 | 河南师范大学 | A kind of fluorine richness molecular sieve H ZSM 35 and preparation method thereof |
| CN109420517A (en) * | 2017-08-30 | 2019-03-05 | 北京化工大学 | A kind of method that methane low temperature conversion prepares higher hydrocarbon |
| CN109420517B (en) * | 2017-08-30 | 2020-09-04 | 北京化工大学 | Method for preparing higher hydrocarbon by methane low-temperature conversion |
| CN111298829A (en) * | 2020-04-03 | 2020-06-19 | 大连理工大学 | Preparation method and application of catalyst with strong anti-carbon performance in reaction for preparing aromatic hydrocarbon from methane in oxygen-free mode |
| CN112044457A (en) * | 2020-08-14 | 2020-12-08 | 北京航天试验技术研究所 | Supported orthohydrogen conversion catalyst and preparation method thereof |
| CN112044457B (en) * | 2020-08-14 | 2023-06-16 | 北京航天试验技术研究所 | Supported normal-para-hydrogen conversion catalyst and preparation method thereof |
| CN112221538A (en) * | 2020-10-12 | 2021-01-15 | 南京理工大学 | Preparation method of fluoroalkyl modified cellulose supported palladium catalyst |
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