CN1077809C - Catalyst for preparing dimethyl ether from gas containing carbon monoxide and hydrogen - Google Patents

Catalyst for preparing dimethyl ether from gas containing carbon monoxide and hydrogen Download PDF

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CN1077809C
CN1077809C CN96115507A CN96115507A CN1077809C CN 1077809 C CN1077809 C CN 1077809C CN 96115507 A CN96115507 A CN 96115507A CN 96115507 A CN96115507 A CN 96115507A CN 1077809 C CN1077809 C CN 1077809C
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component
gas
catalyst
catalyzer
reaction
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CN1172694A (en
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石仁敏
蔡光宇
刘中民
孙承林
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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Abstract

A catalyst for preparing dimethyl ether from gas containing CO and H2 is compounded from a modified molecular sieve and a hydrogenated Cu-Zn component added with right quantity of activity assisting components. In the modification treatment, an amount of one or various kinds of IA, IB, IIA, IIB, IIIA, VA and lanthanide is introduced into a zeolite molecular sieve, the activity assisting component added to the Cu-Zn component comprises one of boron, aluminum, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, zirconium, molybdenum, cadmium, tin, tungsten, rhenium and lanthanide, or elementary substances of a plurality of elements or oxides thereof. The catalyst has the advantages of high catalytic activity, dimethyl ether selectivity, and high carbon utilization rate and stability.

Description

Be used for producing the catalyzer and the application of dme by containing carbon monoxide and hydrogen
The present invention is a kind of about from synthetic gas, the various H that contain such as water-gas and semi-water gas 2Directly produce the Preparation of catalysts method and the utilisation technology thereof of dme with the gas of CO.
Dme is a kind of traditional chemical industrial product, and the past, output and demand were all less usually as methylating agent or solvent and be used to industries such as chemical industry, dyestuff and medicine.But along with dme constantly being found and expanding of many new purposes of chemical industry, the energy and aspect such as civilian, its market demand is also increasing rapidly, thereby has been subjected to increasing attention.Except in industries such as chemical industry and medicine, being used as methylating agent, also be widely used as various aerosols, propellent, cooling agent and fuel dope etc.Particularly in recent years, based on the mankind for the needs that obtain the energy and petrochemicals from non-petroleum path, what people also explored dme purely or contained dme mixs up thing directly as automobile-used or other domestic fuel, realizing fully and cleanburning, and it is described as " fuel of 21st century ".
Produce the research of the catalyzer of dme and corresponding Technology thereof from middle nineteen seventies by synthetic gas step of setting out.USP 3,894, and 102 grades have proposed to use the result who makes methyl alcohol and dme on the composite catalyst that Cu, Zn, the synthetic component of Cr oxide compound methyl alcohol and acidic components such as aluminum oxide or Hydrogen Y zeolite molecular sieve make.USP 4,536, and 485 have proposed to produce the result of dme on the composite catalyst that the ZSM-5 of nitrogen atom alkaline purification molecular sieve is made as the acidic dehydration component.Present inventors once proposed a series of correlation techniques, as CN 1,067,878 two component catalysts that disclose applicable industry catalst for synthesis of methanol and acidic dehydration catalyst system from synthetic gas make dme and and then make the result of low-carbon alkene, CN 1,085,824A discloses element modified Al such as using boron, titanium, phosphorus 2O 3Processing method and CN 1,087,033 by preparation of dimethyl ether from synthesis gas on the catalyzer that the industry catalst for synthesis of methanol is composited disclose with the result who produces dme on industrial catalst for synthesis of methanol and the compound catalyzer that obtains of mordenite.Can see that from the application example of above-mentioned patent the catalyzer that above patented method is made generally will just show active preferably at 250～280 ℃.Because preparation of dimethyl ether from synthesis gas is a reaction process that low temperature is favourable, and the high-temperature stability of copper containing catalyst is relatively poor.So use above-mentioned patented method, be difficult to obtain very high feed stock conversion and very long catalyzer work-ing life usually.The catalyzer that development has catalytic activity and stability is the key of this technical applicationization.
The present invention is directed to the existing existing deficiency of catalyzer, a kind of catalytic activity, selectivity and the very high synthesizing dimethyl ether one-step with synthesis gas as well catalyzer of stability are provided, and determined to be adapted to the optimum process condition of this catalyzer, make it finally to develop into and be fit to the practical technique that industrial production is used.
Become in the dme reaction process in the direct thing of synthetic gas, comprising three principal reaction steps interrelated, that continue and carry out:
-90.4KJ/mol (1)
-23.4KJ/mol (2)
-41.0KJ/mol (3) is although three reactions all are reversible reaction, because the product of each reactions steps all consumes by next step reaction, makes entire reaction course usually carry out departing under the state of thermodynamic(al)equilibrium.So compare with simple methyl alcohol building-up reactions, the reaction conditions gentleness of direct synthesis of dimethyl ether from synthesis gas process many, and the CO per pass conversion is also much higher.In addition, aforementioned synthetic gas directly produce the dme process through three principal reaction steps after, it reacts metering-type only and can write
During promptly reacting ,-245.2KJ/mol (4) have 1/3 CO to change useless CO into approximately 2, add other side reaction that takes place in the process, make the carbon utilisation rate of this process be lower than and be usually less than 65%, reduced the economy of this process.
The present invention generates from promoting methyl alcohol formation reaction and Dehydration of methanol, inhibition carbonic acid gas, the aspect factors such as surface-active structure of the catalyzer under the stopping reaction state are set out and are selected the appropriate catalyst constituent for use, improved activity of such catalysts, selectivity and stability.The raising of the raising of catalyst activity, particularly low temperature active makes this reaction process to carry out under lower temperature, thereby obtains higher thermodynamic(al)equilibrium transformation efficiency, and to CO 2The restraining effect of formation reaction then makes the intermediate product of reaction have certain concentration distribution, makes clean reaction metering-type different with formula (4) and become
(5) x represents to be converted into the CO molecule number of methyl alcohol and dme in the formula, and y represents to be transformed to CO 2The CO molecule number.Because x＞1 and y＜1, the carbon utilisation rate of entire reaction is improved.
Catalyzer involved in the present invention adds H by being used for CO 2Catalyst component and solid acid catalyst dehydration component are composited.Be about to above-mentioned CO and add H 2Component and acidic dehydration component mix by suitable proportion, and compacting gets in flakes again.Co hydrogenation catalyst component in the catalyzer of making accounts for 50～80%, and the acidic dehydration catalyst component concentration is 20～50%.
In the co hydrogenation active ingredient that the present invention adopts, based on the oxide compound of copper, zinc, add the simple substance of in small amount of boron, aluminium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, zirconium, molybdenum, silver, cadmium, tin, tungsten, rhenium and the lanthanon one and several elements or its oxide compound as auxiliary agent.It consists of plumbous oxide 34～75%, zinc oxide 24～65%, auxiliary agent 1～25%, hydrogenation activity components matching such as the auxiliary agent of these introducings and copper zinc, improved the catalytic activity to co hydrogenation, particularly low-temperature catalytic activity, and certain separation and restraining function have been played in the surfactivity center of catalyzer, stablize the surface-active structure of catalyzer, improved the stability of catalyzer.Adopt Na in the preparation 2CO 3Or NaOH, or (NH 3) 2CO 3Or NP 4OH is a precipitation agent, and nitrate or acetate alkaline hydrolysis with copper and zinc make the mixed copper zinc oxide, and then to the nitrate that wherein adds an amount of aforementioned auxiliary element, acetate or oxide compound, drying and roasting decomposition forms again.Also can adopt dipping or solid blended method to introduce an amount of aforementioned auxiliary agent in the commercially available methanol catalyzer, the method for drying and roasting decomposition is made again.Above-mentioned roasting was carried out under 300～500 ℃ 1～10 hour.
The present invention adopts the zeolite molecular sieve of the pore structure that has stronger dehydration of alcohols catalytic activity and be fit to as the acidic dehydration component, and particularly those ZSM-5, ZSM-11, Y type and zeolite betas with stronger acid and slower knot carbon speed are proved to be more effective acidic dehydration component.In order further to delay the knot carbon stall degree of acidic components, introduce in an amount of IA, IB, IIA, IIB, IIIA, VA and the lanthanon one or more oxide compound or ion as modification agent, acidity is adjusted to suitable intensity, make it corresponding to NH 3Desorption peaks temperature in the-TPD spectrogram is 180～450≤scope in, thereby make catalyzer have longer stable life cycle.The content of properties-correcting agent is 0.5～10% of acidic dehydration catalyst component, can adopt ion-exchange, impregnating method to introduce, and decomposes through 450～650 ℃ of roastings to form again.
Use the catalyzer that aforesaid method makes and have very high co hydrogenation catalytic activity, the generation of the carbonic acid gas in the reaction is had the obvious suppression effect, what can be applicable to multiple composition contains CO and H 2The raw material source of the gas can obtain the high product productive rate under the reaction conditions of gentleness, and can be in prolonged operation maintenance stable catalytic performance in service.
The suitable temperature of reaction of this kind catalyzer is 180～320 ℃, and optimum temperature range is 200～280 ℃; Suitable working pressure is 1.0～10.0MPa, and best luxurious power scope is 2.0～6.0MPa; Suitable charging air speed is 500～5000 (v/v.h), and best air speed scope is 1000～3000 (v/v.h); The suitable proportion of the hydrogen/carbon ratio in the reaction raw materials is 0.8: 1 to 4: 1, and the optimum proportion scope is 1: 1 to 3: 1, and can contain portion C O 2With other inert component.Oxygen in the raw material, sulphur and chlorine can seriously reduce activity of such catalysts, even cause catalyst deactivation, need strict the processing, and its content is lower than below the 0.5ppm.
The present invention will be able to more full and accurate description by following application example.
Embodiment 1
Get Cu (NO 3) 23H 2O 242 gram and Zn (NO 3) 26H 2O 150 grams are dissolved in the 435ml deionized water Dropwise 5 %Na 2CO 3Solution 320ml filters, and leaches thing to there not being NO with deionized water wash 3-Be detected, the gained solid is designated as A.Place baking oven dry under 110 ℃ A,, obtain solid 118.8 grams, be called B in 350 ℃ of following roastings 2 hours.
Embodiment 2
With 8.8 grams, AgNO 3Be dissolved in the 35.4ml water, add A, 60 ℃ are stirred down hour, evaporation as for, in 350 ℃ of following roastings 2 hours, obtain solid 124.2 grams, be designated as C.
Embodiment 3
With 63.6 gram Cr (NO 3) 39H 2O is dissolved in the 50ml water, adds the B121 gram, and 60 ℃ were stirred 1 hour down, is evaporated to driedly, in 350 ℃ of following roastings 2 hours, obtains solid 129.6 grams, is designated as D.
Embodiment 4
With 14.9 gram Ce (NO 3) 39H 2O is dissolved in the 40ml water, adds commodity catalst for synthesis of methanol 95 grams, and 60 ℃ were stirred 1 hour down, evaporation as for, in 350 ℃ of following roastings 2 hours, obtain solid 99.6 grams, be designated as E.
Embodiment 5
With 10.2 gram Ca (NO 3) 2Be dissolved in the 60ml water, add 47.5 gram HZSM-5 molecular sieves, 80 ℃ were soaked 1 hour down, filter, and drying, 500 ℃ of following roastings 2 hours obtain solid 49.8 grams, are designated as F.
Embodiment 6
With 9.2 gram Mg (NO 3) 2Be dissolved in the 60ml deionized water, add 48.5 gram HZSM-5 molecular sieves, 80 ℃ of dippings 1 hour down filter, drying, and 500 ℃ of following roastings 2 hours obtain solid 49.9 grams, are designated as G.
Embodiment 7
Respectively 10 gram B, C, D, E are pulverized, mix with 5 gram F, film-making is pulverized, and the gained catalyzer is called H, I, J, K.
Embodiment 8
Brokenly mix 10 gram E are crooked with 5 gram G, film-making, pulverizing, the gained catalyzer is L.
Embodiment 9～13
Get catalyzer H, I, J, K, L2ml respectively, in the internal diameter 8mm stainless steel fixed-bed reactor of packing into, under 260 ℃, with 5%H2 hydrogen/nitrogen mixed gas reductase 12 hour, with H 2/ CO-2: 1 synthetic gas is a raw material, carries out catalyzed reaction, the results are shown in table 1
Embodiment 14
Get catalyzer J2ml, in the internal diameter 8mm stainless steel fixed-bed reactor of packing into, under 260 ℃, with containing 5%H 2Hydrogen/nitrogen mixed gas reductase 12 hour, with H 2/ CO=2: 1 synthetic gas is a raw material, is 210～320 ℃ in temperature of reaction, working pressure 3.0MPa, charging air speed 1000h -1Under the condition, continuous online reaction 2200 hours, the CO transformation efficiency keeps more than 75%.
Embodiment 15
Get catalyzer K3375 gram, put Φ 4000 * 40 * 4 solid fixed bed reactors, with containing 5%H 2Hydrogen nitrogen mixed gas reductase 12 0 hour (260 ℃ of the highest reduction temperatures), be that raw material (consists of H with industrial semi-water gas 244.6%, CO22.7%, N 220.1%, CH 41.1%, CO 211.5%), 220 ℃ of temperature, pressure 3.5MPa and air speed 1000h -1Carry out catalyzed reaction under the condition, CO transformation efficiency 80.2%, the dme selectivity is near 100%, carbon utilisation rate 70.7%.
Embodiment 16
The catalyzer identical with example 15 arranged, the same reaction device, identical reducing program and reaction raw materials are at 235 ℃ of temperature, pressure 3.5～4.5MPa and air speed 1000h -1Under the condition, successive reaction test 1000 hours, the CO transformation efficiency remains on more than 75%, and the dme selectivity is near 100%, and carbon utilisation rate reaches 70%.
Comparative example 1～4
Press document [1] [CN1,067,878 (1993)], document [2] [Catatysist today, 8 (1991)], document [3] (I.E.C.Proid.Res.Dev., 25,2,262 (1980)] and document [4]] USP.4,536,485 (1985)] technology that is provided is carried out CO and H by the real embodiment 9 described conditions of answering 2The synthetic dme of producing reacts, and it the results are shown in table 1
The catalytic perfomance of several catalyzer of table 1.
Catalyzer Temperature (℃) Pressure (MPa) Air speed (h -1) CO transformation efficiency (mol%) Dme selectivity (mol%) Carbon utilisation rate (mol%)
Embodiment 9 H 240 3.0 1000 85.5 93.6 63.2
Embodiment 10 I 240 3.0 1000 96.1 91.4 70.6
Embodiment 11 J 210 3.0 1000 93.0 92.1 66.4
Embodiment 12 K 240 3.0 3000 90.1 94.0 64.5
Embodiment 13 L 240 3.0 1000 90.0 95.8 64.9
Comparative example 1 Document [1] 260 3.0 1000 84.4 92.1 —
Comparative example 2 Document [2] 250 5.6 3000 65 76.0 —
Comparative example 3 Document [3] 280 2.1 1000 78 － －
Comparative example 4 Document [4] 280 6.0 － 71.3 － －
Can be found out that by the listed data result of table 1 under identical reaction condition, feed stock conversion is much higher on catalyst of the present invention; If thereby wish to get identical result, required reaction condition is also much gentle. Particularly, the present invention has the following advantages;
1. can adopt lower reaction temperature, thereby obtain higher equilibrium conversion, and be conducive to the prolongation of stable life cycle of the copper zinc component of poor high temperature stability;
2. can adopt lower operating pressure, improve the flowing velocity of reaction logistics, be conducive to the derivation of reaction heat, thereby be conducive to the prolongation of the stable life cycle of catalyst;
3. higher purpose selectivity of product and raw material availability can obviously reduce the consumption of raw materials of unit product, thereby reduce cost, increase the benefit;
Higher conversion ratio so that the recycle ratio of unreacting material greatly reduce, thereby reduce unit scale and energy consumption, further reduce the production cost of product;
5. can under the prerequisite of the higher feed stock conversion of maintenance, adopt higher charging air speed, improve product yield, obtain higher device efficiency and the economic benefit of overall process.

Claims (2)

1. one kind is used for by containing CO and H 2Gas is produced the catalyzer of dme, and it is to add H by CO 2Catalyst component and acidic dehydration catalyst component are composited, and it is characterized in that CO adds H 2Component contains the copper zinc element as main active ingredient, and introduces and to help active ingredient, i.e. aluminium, and titanium, vanadium, chromium, manganese, iron, cobalt, nickel, zirconium, molybdenum, cadmium, tin, tungsten, a kind of simple substance or its oxide compound of or several elements in rhenium and the lanthanum element, and CO adds H 2Contain cupric oxide 34～75% in the component, zinc oxide 24～65% helps active ingredient 1～25%; The acidic dehydration component is meant to be handled through the modification agent modification; A kind of in β-type molecular sieve, Y zeolite, type ZSM 5 molecular sieve and the ZSM-11 type molecular sieve or several; Modification agent is meant the oxide compound or the ion of a kind of or several elements in IA, IB, IIA, IIB, IIIA, VA and the lanthanon; Modification agent content is 0.5～10% in the acidic dehydration component; Catalyst weight consists of CO and adds H 2Component 50～75%, acidic dehydration component are 25～50%.
2. a method of carrying out carbon dioxide hydrogenation reaction in the presence of the described catalyzer of claim 1 is characterized in that temperature of reaction is 200～300 ℃, and working pressure is 2.0～6.0MPa, and the charging air speed is 1000～3000h -1Unstripped gas is selected from synthetic gas, water-gas, various CO and the H of containing of semi-water gas 2Gas mixture, its hydrogen/carbon ratio is 1.0～3.0.
CN96115507A 1996-08-02 1996-08-02 Catalyst for preparing dimethyl ether from gas containing carbon monoxide and hydrogen Expired - Fee Related CN1077809C (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100374203C (en) * 2006-04-13 2008-03-12 中国科学院大连化学物理研究所 Homogeneous temperature type catalyst for preparing dimethyl ether from methanol and use
KR100812099B1 (en) * 2006-11-28 2008-03-12 한국가스공사 Method of preparing catalyst for making dimethylether from syngas with carbon dioxide
CN103084203A (en) * 2011-10-31 2013-05-08 东北大学 Method for preparing CuZnAlFe system catalyst for catalyzing preparation of dimethyl ether through reacting CO2 with H2
CN108727194B (en) * 2018-05-18 2021-03-26 中国科学院青岛生物能源与过程研究所 Method for synthesizing dialkyl carbonate from biomass-based synthesis gas
CN117720954B (en) * 2024-01-25 2024-05-28 青岛康洁聚能科技有限公司 Non-noble metal carbon monoxide combustion improver and preparation method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4536485A (en) * 1984-01-10 1985-08-20 Haldor Topsoe A/S Process for the preparation of catalysts for use in ether synthesis
CN1085824A (en) * 1993-08-31 1994-04-27 中国科学院大连化学物理研究所 A kind of by preparation of dimethyl ether from synthesis gas reaction catalyst and preparation dimethyl ether technology thereof
CN1087033A (en) * 1992-11-17 1994-05-25 中国科学院大连化学物理研究所 Be converted into the dme metallic zeolite catalyst for reaction by synthetic gas
US5466720A (en) * 1991-11-11 1995-11-14 Kaoru Fujimoto Method of producing dimethyl ether

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4536485A (en) * 1984-01-10 1985-08-20 Haldor Topsoe A/S Process for the preparation of catalysts for use in ether synthesis
US5466720A (en) * 1991-11-11 1995-11-14 Kaoru Fujimoto Method of producing dimethyl ether
CN1087033A (en) * 1992-11-17 1994-05-25 中国科学院大连化学物理研究所 Be converted into the dme metallic zeolite catalyst for reaction by synthetic gas
CN1085824A (en) * 1993-08-31 1994-04-27 中国科学院大连化学物理研究所 A kind of by preparation of dimethyl ether from synthesis gas reaction catalyst and preparation dimethyl ether technology thereof

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