Catalyst and method for preparing liquid fuel and light olefins by direct conversion of syngas

Abstract

Direct conversion of syngas produces liquid fuels and light olefins. The catalytic reaction is conducted on a fixed bed or a moving bed. The catalyst comprises A and B components. The component A is composed of active metal oxides, and the active ingredients of the component B are zeolites with a MEL structure. The distance between the geometric centers of catalyst A and catalyst B particles is 2 nm-10 mm; a weight ratio of the catalyst A to the catalyst B is 0.1-20. The pressure of the syngas is 0.1-10 MPa; reaction temperature is 300-600° C.; and space velocity is 300-10000 h.sup.−1. The reaction mainly produces gasoline with high octane number, and co-generates light olefins. Meanwhile, the selectivity for a methane byproduct is low (less than 10%).

Claims

1. A catalyst comprising component A and component B, wherein the component A comprises a metal oxide selected from MnO, Cr.sub.2O.sub.3, ZnO, CeO.sub.2, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4, MnZrO.sub.4, ZnCr.sub.2O.sub.4, ZnAl.sub.2O.sub.4, CoAl.sub.2O.sub.4, FeAl.sub.2O.sub.4, and mixtures thereof, wherein the component B comprises a zeolite having a MEL structure, wherein the metal oxide has oxygen vacancies at an oxygen vacancy concentration of 20-90%, and wherein the oxygen vacancy concentration equals 100% less a percentage of a weight of oxygen atoms in the metal oxide in a weight of a stoichiometric amount of oxygen atoms in the metal oxide.

2. The catalyst according to claim 1, wherein the catalyst component A is one or more metal oxides selected from MnO, Cr.sub.2O.sub.3, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4, MnZrO.sub.4, ZnAl.sub.2O.sub.4, CeO.sub.2, CoAl.sub.2O.sub.4, and FeAl.sub.2O.sub.4, the zeolite having MEL structure is composed of H, O, Si and Al, and the component B optionally comprises one or more dispersing agents selected from Al.sub.2O.sub.3, graphite, SiO.sub.2, ZrO.sub.2, TiO.sub.2, Cr.sub.2O.sub.3, Ga.sub.2O.sub.3, CaO, MgO, CeO.sub.2, In.sub.2O.sub.3, and SnO.sub.2, and wherein a content of the dispersing agents is 0-50% wt of a total weight of the component B.

3. The catalyst according to claim 1, wherein a distance between a geometric center of the metal oxide in the component A and the zeolite particle in the component B is 20 nm-10 mm.

4. The catalyst according to claim 1, wherein a weight ratio of the metal oxide in the component A to the component B is within a range of 0.1-20 times.

5. The catalyst according to claim 1, wherein the metal oxide is in form of crystals having a size of 5-30 nm, and the oxygen vacancies reside within a depth of 0.3 nm from a surface of the crystals.

6. The catalyst according to claim 1, wherein the component A comprises a dispersing agent selected from Al.sub.2O.sub.3, Cr.sub.2O.sub.3, ZrO.sub.2, and TiO.sub.2, and a content of the dispersing agent in the component A is 10-90 wt %.

7. A method for preparing liquid fuels and light olefins by direct conversion of syngas, comprising contacting a syngas with a catalyst of claim 1 comprising component A and component B, wherein the component A comprises a metal oxide selected from MnO, Cr.sub.2O.sub.3, CeO.sub.2, ZnO, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4, MnZrO.sub.4, ZnCr.sub.2O.sub.4, ZnAl.sub.2O.sub.4, CoAl.sub.2O.sub.4, FeAl.sub.2O.sub.4, and mixtures thereof, wherein the component B comprises a zeolite having a MEL structure.

8. The method according to claim 7, wherein a pressure of the syngas is 0.1-10 MPa, a reaction temperature is 300-600° C., and a space velocity of the syngas is 300-10000 h.sup.−1.

9. The method according to claim 7, wherein a molar ratio of H.sub.2 to CO in the syngas 0.2-3.5.

10. The catalyst according to claim 2, wherein the component A is selected from MnO, Cr.sub.2O.sub.3, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4, MnZrO.sub.4, CeO.sub.2, CoAl.sub.2O.sub.4, FeAl.sub.2O.sub.4, and mixtures thereof.

11. The catalyst according to claim 3, wherein the distance between geometric center of the metal oxide of the component A and the geometric center of the zeolite particle in the component B is 100 nm-0.5 mm.

12. The catalyst according to claim 4, wherein the weight ratio of the metal oxide in the component A to the component B is 0.3-5.

13. The catalyst according to claim 5, wherein the oxygen vacancy concentration is 50-90%.

14. The method according to claim 8, wherein the pressure of the syngas is 2-8 MPa.

15. The method according to claim 8, wherein the reaction temperature is 300° C.-500° C.

16. The method according to claim 9, wherein the molar ratio of H.sub.2 to CO in the syngas 0.3-2.5.

17. The catalyst of claim 1, wherein the component A and the component B are mixed by stirring, ball milling, shaking table mixing, or grinding.

18. A catalyst comprising component A and component B, wherein the component A comprises a metal oxide selected from MnO, Cr.sub.2O.sub.3, CeO.sub.2, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4, MnZrO.sub.4, ZnCr.sub.2O.sub.4, ZnAl.sub.2O.sub.4, CoAl.sub.2O.sub.4, FeAl.sub.2O.sub.4, and mixtures thereof, and the component B comprises a zeolite having a MEL structure, wherein the metal oxide has oxygen vacancies at an oxygen vacancy concentration of 20-90%, and wherein the oxygen vacancy concentration equals 100% less a percentage of a weight of oxygen atoms in the metal oxide in a weight of a stoichiometric amount of oxygen atoms in the metal oxide.

19. The catalyst of claim 18, consisting of the component A and the component B.

Description

DETAILED DESCRIPTION

(1) The present invention is further illustrated below by embodiments, but the scope of claims of the present invention is not limited by the embodiments. Meanwhile, the embodiments only give some conditions for achieving the purpose, but it doesn't mean that the conditions must be satisfied to achieve the purpose.

Embodiment 1

(2) I. Preparation of Catalyst A

(3) (I) Synthesizing ZnO material with polar surface through an etching method:

(4) (1) 0.446 g (1.5 mmol) of Zn(NO.sub.3).sub.2.6H.sub.2O and 0.480 g (12 mmol) of NaOH are weighed; 30 ml of deionized water is weighed and added to the material, and stirred for a time greater than 0.5 h to uniformly mix a solution; the temperature is increased to 160° C. with the reaction time of 20 h; precipitate is decomposed into zinc oxide, and naturally cooled to room temperature; reaction liquid is centrifugally separated to collect the centrifugally separated precipitate; and the precipitate is washed with deionized water twice to obtain ZnO oxide;

(5) (2) an etching agent, such as oleic acid, hexamethylenetetramine, ethylenediamine, ammonia and hydrazine hydrate are ultrasonically mixed with ZnO oxide uniformly under normal temperature; the ZnO oxide is immersed in the solution of the etching agent; and a complexing or direct reduction reaction is formed by the etching agent and the zinc oxide; the above suspended matter is heated; then the suspended matter is taken out for washing and filtering the suspended matter to obtain active nano ZnO material having a large amount of surface oxygen holes.

(6) In Table 1: the mass ratio of the catalyst to the etching agent is 1:3. The mass ratio of the oleic acid to the hexamethylenetetramine is 1:1, without solvent. The mass ratio of the oleic acid (5 wt %) to the hydrazine hydrate is 95:5, without solvent. Specific treatment conditions include the etching agent, temperature, treatment time and atmosphere types as shown in Table 1 below.

(7) (3) Drying or Drying and Reducing:

(8) After centrifuging or filtering the above obtained products and washing the products with deionized water, the products are dried, or dried and restored in an atmosphere which is inert gas or a gas mixture of inert gas and a reducing atmosphere, wherein the inert gas is one or more than one of N.sub.2, He and Ar, the reducing atmosphere is one or more than one of H.sub.2 and CO; a volume ratio of the inert gas to the reducing gas in the dried and restored gas mixture is 100/10-0/100, the temperature of drying and restoring is 350° C., and time is 4 h. ZnO material with abundant oxygen vacancies on the surface is obtained. Specific samples and preparation conditions thereof are shown in Table 1 below. The surface oxygen vacancy concentration is defined as: (100%-percent of the molar weight of oxygen atoms in theoretical stoichiometric ratio of oxygen molar content).

(9) TABLE-US-00001 TABLE 1 Preparation of ZnO Material and Parameter Performance Drying or Drying and Surface Temperature (° C.) Reducing Oxygen Sample and Carrier Gas Temperature/° C. Vacancy Number Etching Agent (V/V) Time/Minute and Atmosphere Concentration ZnO 1 oleic 100, N.sub.2 30  30, N.sub.2 21% acid-hexamethylenetetramine ZnO 2 oleic acid 100, 5% H.sub.2/N.sub.2 30 300, 5% H.sub.2/N.sub.2 45% ZnO 3 oleic acid 120, 5% CO/Ar 60 350, 5% CO/Ar 73% ZnO 4 oleic acid-5 wt % hydrazine 140, 5% H.sub.2/Ar 60 310, 5% H.sub.2/Ar 67% hydrate ZnO 5 ethylenediamine 100, 5% NH.sub.3/Ar 30 250, 5% NH.sub.3/Ar 30% ZnO 6 ethylenediamine 140, 5% NO/Ar 90 150, 5% NO/Ar 52% ZnO 7 20 wt % ammonium 100, Ar 30 120, 5% CO/Ar 22% hydroxide ZnO 8 20 wt % ammonium 140, 5% NH.sub.3/5% NO/Ar 90 400, He 29% hydroxide

(10) The surface oxygen vacancies are the percent of the molar weight of oxygen atoms in theoretical stoichiometric ratio of oxygen molar content within a distance range of depth 0.3 nm from the surfaces of the crystals to the internal direction of the crystals.

(11) As a reference example, ZnO 9 which is not etched in step (2) and has no oxygen vacancy on the surface; and metal Zn 10 by completely reducing Zn.

(12) (II) Synthesizing MnO material with polar surface through an etching method: the preparation process is the same as that of the above (I). The difference is that, the precursor of Zn is changed for the corresponding precursor of Mn, which is one of manganous nitrate, manganese chloride and manganese acetate.

(13) The etching process is the same as the preparation processes of products ZnO 3, ZnO 5 and ZnO 8 in step (2) in above (I). The catalyst having a great number of surface oxygen vacancies is synthesized. The surface oxygen vacancies are 56%, 36% and 27%.

(14) Corresponding products are defined as MnO 1-3.

(15) (III) Synthesizing CeO.sub.2 material with polar surface through an etching method: the preparation process is the same as that of the above (I). The difference is that, the precursor of Zn is changed for the corresponding precursor of Ce, which is one of cerium nitrate, cerium chloride and cerous acetate.

(16) The etching process is the same as the preparation processes of products ZnO 3, ZnO 4 and ZnO 8 in step (2) in above (I). The catalyst having a great number of surface oxygen vacancies is synthesized. The surface oxygen vacancies are 67%, 38% and 25%.

(17) Corresponding products are defined as CeO 1-3.

(18) (IV) Synthesizing Cr.sub.2O.sub.3 material with polar surface through an etching method:

(19) the preparation process is the same as that of the above (I). The difference is that, the precursor of Zn is changed for the corresponding precursor of Cr, which is one of chromic nitrate, chromium chloride and chromic acetate.

(20) The etching process is the same as the preparation processes of products ZnO 3, ZnO 4 and ZnO 8 in step (2) in above (I). The catalyst having a great number of surface oxygen vacancies is synthesized. The surface oxygen vacancies are 45%, 29% and 20%.

(21) Corresponding products are defined as Cr.sub.2O.sub.3 1-3.

(22) (V) Synthesizing nano ZnCr.sub.2O.sub.4, ZnAl.sub.2O.sub.4, MnCr.sub.2O.sub.4, MnAl.sub.2O.sub.4 and MnZrO.sub.4 spinel with high specific surface area and high surface energy:

(23) zinc nitrate, aluminum nitrate, chromic nitrate, manganous nitrate and zirconium nitrate are adopted as precursors, and mixed with urea at room temperature in water; the above mixed liquid is aged; then the mixed liquid is taken out for washing, filtering and drying; and the obtained solid is roasted under an air atmosphere to obtain spinel oxide which grows along the (110) crystal plane direction. The sample is also treated by the etching method to synthesize the catalyst with a great number of surface oxygen vacancies. The etching process and aftertreatment process are the same as step (2) and step (3) in above (I). The sample has large specific surface area and many surface defects, and can be applied to catalyzing the conversion of syngas.

(24) Specific samples and preparation conditions thereof are shown in Table 2 below. Similarly, the surface oxygen vacancies are defined as: (1-percent of the molar weight of oxygen atoms in theoretical stoichiometric ratio of oxygen molar content).

(25) TABLE-US-00002 TABLE 2 Preparation of Spinel Material and Performance Parameters Stoichiometric Ratio of Metal Elements in Spinel and Final Molar Etching Agent, Concentration Aging Roasting Temperature/° C., Surface Sample of Metal in Water Temperature ° C. Temperature ° C. Atmosphere and Oxygen Number (mmol/L) and Time h and Time h Time/min Vacancy spinel 1 ZnCr = 1:2, 120, 24 600, 48 oleic acid, 120, 41% Zn is 50 mM 5% H.sub.2/Ar, 60 spinel 2 ZnAl = 1:2, 130, 20 700, 24 oleic acid, 120, 72% Zn is 50 mM 5% H.sub.2/Ar, 60 spinel 3 MnCr = 1:2, 140, 18 750, 16 oleic acid, 120, 83% Mn is 50 mM 5% H.sub.2/Ar, 60 spinel 4 MnAl = 1:2, 145, 16 800, 10 oleic acid, 120, 20% Mn is 50 mM 5% H.sub.2/Ar, 60 spinel 5 MnZr = 1:2, 150, 12 900, 3  oleic acid, 120, 24% Mn is 50 mM 5% H.sub.2/Ar, 60

(26) (V) Synthesizing nano FeAl.sub.2O.sub.4, CoAl.sub.2O.sub.4 and spinel with high specific surface area and high surface energy: the preparation process is the same as (2) of the above (IV). The difference is that, the precursor of Zn is changed for the corresponding precursor of Fe or Co, which is one of ferric nitrate, ferric chloride and ferric citrate or one of cobalt nitrate, cobalt chloride and cobalt acetate.

(27) The etching process is the same as the preparation processes of products ZnO 3 and ZnO 5 in step (2) in above (I). The catalyst having a great number of surface oxygen vacancies is synthesized. The surface oxygen vacancies are 77% and 51%.

(28) Corresponding products are defined as spinel 6 and spinel 7.

(29) (VI) Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 dispersed active metal oxide

(30) Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 dispersed active metal oxide is prepared through a precipitate deposition method by taking Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 as carriers. Taking preparation of oxide by dispersed ZnO as an example, commercial Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 carrier is dispersed in a base solution in advance, and then mixed and precipitated at room temperature with a sodium hydroxide precipitant by taking zinc nitrate as raw material. The molar concentration of Zn.sup.2+ is 0.067M; and the ratio of molar fractions of Zn.sup.2+ and the precipitant is 1:8; and then aging is conducted at 160° C. for 24 hours to obtain carrier Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 dispersed ZnO oxide (the contents of the dispersing agents in catalyst A are 0.1 wt %, 10 wt % and 90 wt %).

(31) The etching process is the same as the preparation processes of products ZnO 3, ZnO 5 and ZnO 8 in step (2) in above (I). The catalyst having a great number of surface oxygen vacancies is synthesized. The surface oxygen vacancies are 65%, 30% and 25%. The aftertreatment process is the same as step (3) in above (I).

(32) Corresponding products from top to bottom are defined as dispersed oxides 1-3.

(33) The same method is used to obtain carrier Cr.sub.2O.sub.3, Al.sub.2O.sub.3 or ZrO.sub.2 dispersed MnO oxide (the contents of the dispersing agents in catalyst A are 5 wt %, 30 wt % and 60 wt %). The surface oxygen vacancies are 62%, 27% and 28%. Corresponding products from top to bottom are defined as dispersed oxides 4-6.

(34) II. Preparation of Zeolite Having MEL Topology, i.e., Component B:

(35) 1) The specific preparation process is as follows:

(36) The preparation of the MEL zeolite:

(37) NaOH, NaAlO.sub.2, silica sol, TBABr and water are weighed successively in the proportion of 2.9Na.sub.2O:1Al.sub.2O.sub.3: 9TBABr:30SiO.sub.2:1260H.sub.2O, stirred for 3 h, then transferred into a hydrothermal reactor and sealed in 90 rpm selection oven at 150° C. for 3 days.

(38) Then, the materials are centrifugally washed, dried and roasted, subjected to ion exchange with IM ammonium nitrate solution at 70° C. for 8 h, washed with water, filtered, dried, and roasted at 540° C. for 6 h to obtain an MEL zeolite product.

(39) III. Catalyst Preparation

(40) The component A and the component B in the required ratio are added to the container to achieve the purposes of separation, crushing, uniform mixing and the like through one or more than two of extrusion force, impact force, shear force and friction force generated by high-speed motion of the material and/or the container, so as to realize conversion of mechanical energy, thermal energy and chemical energy by regulating the temperature and the atmosphere of carrier gas, thereby further enhancing the interaction between different components.

(41) In the mechanical mixing process, the mixing temperature can be set as 20-100° C., and the mechanical mixing process can be conducted in an atmosphere or directly in the air. The atmosphere is one or more than one of: a) nitrogen and/or inert gas; b) mixed gas of hydrogen, nitrogen and/or inert gas, with the volume ratio of hydrogen in the mixed gas being 5-50%; c) mixed gas of carbon monoxide, nitrogen and/or inert gas, with the volume ratio of carbon monoxide in the mixed gas being 5-20%; and d) mixed gas of oxygen, nitrogen and/or inert gas, with the volume ratio of oxygen in the mixed gas being 5-20%. The inert gas is one or more than one of helium, argon and neon.

(42) Mechanical stirring: mixing the component A and the component B with a stirring rod in a stirring tank; and regulating the mixing degree and the relative distance of the component A and the component B by controlling stirring time (5 min-120 min) and rate (30-300 r/min).

(43) Ball milling: Rolling at high speed in a grinding tank by using abrasive and the catalysts; and producing strong impact and milling on the catalysts to achieve the effects of dispersing and mixing the component A and the component B. The ratio of the abrasive (which is stainless steel, agate and quartz; and the size range is 5 mm-15 mm) to the catalysts (the mass ratio scope is 20-100:1) is controlled to regulate the particle size and the relative distance of the catalysts.

(44) Shaking table mixing: premixing the component A and the component B and placing the catalysts into the container; realizing the mixing of the component A and the component B by controlling the reciprocating oscillation or circumferential oscillation of a shaking table; and realizing uniform mixing and regulating the relative distance by regulating oscillation speed (range: 1-70 r/min) and time (range: 5 min-120 min).

(45) Mechanical grinding: premixing the component A and the component B and placing the catalysts into the container; and under certain pressure (range: 5 kg-20 kg), making relative motion (speed range: 30-300 r/min) by the ground and mixed catalysts to achieve the effects of regulating the particle size and the relative distance of the catalysts and realizing uniform mixing.

(46) Specific catalyst preparation and parameter features are shown in Table 6.

(47) TABLE-US-00003 TABLE 5 Preparation of Catalysts and Parameter Features Compounding Mode and Condition Ball Milling Mechanical Mechanical Abrasive Rocking Bed Polishing Geometrical Agitation Material, Size Oscillation Pressure (kg) Center Mass Rate (r/min) Range and Speed (r/min) and Relative Distance of Catalyst Catalyst Catalyst Ratio of and Time Catalyst Mass and Time Movement Rate A and B Number Component A Component B A to B (min) Ratio (min) (r/min) Particles A ZnO1 MEL 0.33 5, 3 10 mm B ZnO 2 MEL 0.5 100, 250 200 μm C spinel 3 MEL 2 5 mm stainless 52 μm steel ball, 80:1 D ZnO4 MEL 1 6 mm stainless 30 nm steel ball, 90:1 E ZnO 5 MEL 1 5, 4 8 mm F ZnO 6 MEL 3  60, 100 300 μm G ZnO7 MEL 3 5, 30 100 μm H ZnO8 MEL 1 200, 300 200 nm I spinel 1 MEL 5 6 mm agate ball, 30 μm 100:1 J spinel 2 MEL 1 150, 100 500 nm K spinel 3 MEL 3 15, 200 150 μm L spinel 4 MEL 0.33 20, 300 70 μm M spinel 5 MEL 1 100, 300 200 μm N spinel 6 MEL 3 6 mm quartz, 800 μm 50:1 O spinel 7 MEL 0.33 6 mm quartz, 40 nm 300:1 P MnO 1 MEL 1 10, 100 100 μm Q MnO 2 MEL 1  5, 10 1 mm R MnO 3 MEL 3  60, 100 3 mm S CeO1 MEL 3 50, 30  200 nm T CeO2 MEL 1 100, 300 300 μm U CeO3 MEL 0.33 6 mm quartz, 10 μm 100:1 V Cr2O3-1 MEL 2 5, 30 100 μm W Cr2O3-2 MEL 1 100, 300 400 μm X Cr2O3-3 MEL 0.5 6 mm quartz, 15 μm 100:1 Y dispersed MEL 1 10, 20 6 mm oxide 1 Z dispersed MEL 3 5 mm stainless 20 nm oxide 2 steel ball, 200:1 Z1 dispersed MEL 1 10, 100 60 μm oxide 3 Z2 dispersed MEL 4 30, 60 700 μm oxide 4 Z3 dispersed MEL 3 10, 100 70 μm oxide 5 Z4 dispersed MEL 20 5 mm stainless 5 μm oxide 6 steel ball, 100:1 Z5 MnO 1 MEL 16 100, 200 100 μm Z6 ZnO 1 MEL 0.1 20, 100 200 μm Z7 dispersed MEL 1 20, 300 60 μm oxide 1 Z8 spinel 1 MEL 1.5  60, 100 2 mm Z9 ZnO1 MEL 4 5 mm stainless 5 μm steel ball, 50:1 Z10 MnO 1 MEL 4.5  50, 120 200 μm Z11 dispersed MEL 2.5 100, 200  100 nm oxide 1 Z12 spinel 1 MEL 3 20, 200 50 μm Comparison 1 ZnO 9 MEL 3 20, 30 10 mm Comparison 2 Zn 10 MEL 2  60, 100 200 μm

(48) Example of Catalytic Reactions

(49) A fixed bed reaction is taken as an example, but the catalyst is also applicable to a fluidized bed reactor. The apparatus is equipped with gas mass flow meters and online product analysis chromatography (the tail gas of the reactor is directly connected with the metering valve of chromatography, and thus periodic and real-time sampling and analysis will be achieved).

(50) The above catalyst in the present invention is placed in a fixed bed reactor. The air in the reactor is replaced with Ar; and then the temperature is raised to 300° C. in the H.sub.2 atmosphere, and then the syngas (H.sub.2/CO molar ratio=0.2-3.5) is switched. The pressure of the syngas is 0.5-10 MPa. The temperature is raised to reaction temperature of 300-600° C., and the air velocity of the reaction raw gas is regulated to 500-8000 ml/g/h. On-line chromatography is used to detect and analyze the product.

(51) 1. The reaction performance can be changed by changing the temperature, pressure and space velocity. The selectivity of the gasoline fraction in the product is high and can reach 50-80%. The other products are mainly light olefins with high added value, and the selectivity of the light olefins can reach 10-30%.

(52) Compared with the traditional Fischer-Tropsch synthesis technology, the selectivity of the methane byproduct is low, which is less than 10%. The gasoline composition comprises a large amount of iso-hydrocarbons with high octane value and aromatic hydrocarbons; and the linear hydrocarbons have low selectivity and high oil quality.

(53) TABLE-US-00004 TABLE 6 Application and Effect of Catalysts Hydrocarbon Space Time Oxygen H.sub.2/CO Yield g Hole GHSV Temperature Molar Pressure Olefin/hg Gasoline CH.sub.4 Light Olefin 40 Embodiments Catalyst (h.sup.−1) (° C.) Ratio (MPa) Catalyst Selectivity % Selectivity % Selectivity % 50 1 A 1000 360 2.5 2 0.2 51 9 28 21% 2 B 1000 360 3 4 0.7 67 5 14 45% 3 C 600 370 2.5 3.5 1.5 73 3 18 73% 4 D 1600 350 1 10 1.3 78 2 11 67% 5 E 1400 370 3 1 0.6 55 10 25 30% 6 F 2500 390 0.5 3 1.3 70 4 15 52% 7 G 3000 375 2.5 2.5 0.6 60 7 25 22% 8 H 500 380 2 3.5 0.7 67 7 18 29% 9 I 1100 340 2.5 3.5 0.5 63 6 20 41% 10 J 500 330 1 8 1.5 77 2 11 72% 11 K 3100 430 0.5 3 1.9 71 2 11 83% 12 L 7000 520 1.5 3.5 0.3 65 5 15 20% 13 M 1000 450 0.3 9 0.6 65 6 21 24% 14 N 1000 310 1 3.5 0.6 67 4 20 77 15 O 800 350 1 4.5 0.5 65 5 18 51 16 P 2000 470 1.5 3.5 1.9 74 3 11 56 17 Q 3600 450 2 4 0.8 52 10 24 36 18 R 5500 470 2 3 0.3 52 10 25 27 19 S 700 330 1 5.5 1.9 76 2 11 67 20 T 6000 440 1.5 5 0.6 61 5 22 38 21 U 1800 330 1 6.5 0.3 67 7 27 25 22 V 1500 450 1.5 7 0.9 64 7 22 45 23 W 1500 400 0.5 4 0.4 66 6 24 29 24 X 3000 400 1 5 0.4 60 7 25 20 25 Y 500 360 0.5 5 0.8 61 7 25 65 26 Z 1500 350 1.5 5 0.4 50 10 27 30 27 Z1 2500 410 2.5 6 0.7 67 6 25 25 28 Z2 4000 420 3 2 1.3 63 5 24 62 29 Z3 3000 430 3.5 8 0.4 65 7 19 27 30 Z4 5000 390 3 2.5 0.5 53 8 26 28 31 Z5 2000 410 3.5 1.5 1.4 57 5 28 56 32 Z6 2000 470 0.3 10 0.4 54 8 27 21 33 Z7 2000 340 3.5 1 1.7 78 5 10 65 34 Z8 1000 410 3 3 0.7 51 8 25 41 35 Z9 500 360 3.5 4 0.5 66 7 24 21 36 Z10 4200 410 2 3 1.7 78 5 10 56 37 Z11 1000 350 3.5 2 1.9 79 4 10 65 38 Z12 2000 420 3 4 0.8 59 6 29 41 39 Reference 3000 320 0.5 1 0.07 19 11 18 example 1 40 Reference 2000 450 1 2 1.0 27 31 12 example 2 41 Reference 4000 450 3 3 1.0 37 47 13 example 3 42 Reference 3000 350 2.5 3 0.06 2 64 27 example 4 43 Reference 5000 450 1 4 0.7 ~ 9 50 example 5 44 Reference 2000 410 2 3.5 0.15 ~ 80 11 example 6 45 Reference 3000 410 2.5 4 0.3 5 51 22 example 7 46 Reference 3200 410 3 2 2 41 42 11 example 8 47 Reference 20000 290 2 5.1 1.0 29 12 15 example 9

(54) ZnO in the catalyst in reference example 1 has no oxygen vacancy, and thus the activity is low.

(55) ZnO in the catalyst in reference example 2 is completely reduced into a metallic state, resulting in high selectivity of the methane in the product.

(56) The catalyst adopted in reference example 3 comprises metal ZnCo of the component A and MEL of the component B. The molar ratio of ZnCo is 1:1. The mass ratio of ZnCo to MEL is 1:1. Other parameters and the mixing process are the same as those of catalyst A.

(57) The component A of the catalyst adopted in reference example 4 is MgO without surface oxygen vacancy, and the component B is MEL. Other parameters and the mixing process are the same as those of catalyst A.

(58) The zeolite in the catalyst adopted in reference example 5 is a commodity SAPO-34 purchased from Nankai University Catalyst Factory.

(59) The zeolite in the catalyst adopted in reference example 6 is a small pore zeolite having LEV structure.

(60) The distance between the metal oxide and the zeolite in the catalyst adopted in reference example 7 is 30 mm. Other parameters and the mixing process are the same as those of catalyst A.

(61) The metal oxide in the catalyst adopted in reference example 8 is located in porous channels of the zeolite and is in close contact with the porous channels. Other parameters and the like are the same as those of catalyst A.

(62) A carbon nanotube-limited iron catalyst is adopted in reference example 9, wherein iron load is 10%, and the selectivity of the C.sub.5+ product in the hydrocarbon is 29%.

(63) Explanation of Reaction Results:

(64) Explanation I:

(65) Reaction results of reference examples 5 and 6 show that, the topology is crucial to the selective modulation of the products; SAPO34 structure is suitable for production of C.sub.2-C.sub.4 hydrocarbons; C.sub.3 hydrocarbon products are the most; LEV structure is suitable for production of the methane.

(66) The MEL zeolite used by the present invention has ten-membered ring orifices and a three-dimensional porous channel structure shows the special benefits not owned by zeolites of other structures. The product mainly comprises the gasoline fraction, and the content of iso-paraffins is high. At the same time, light olefins are cogenerated.

(67) Explanation II:

(68) The distance between the metal oxide and the zeolite in the catalyst adopted in reference example 7 is 30 mm. Other parameters and the mixing process are the same as those of catalyst A.

(69) The metal oxide in the catalyst adopted in reference example 8 is located in porous channels of the zeolite and is in close contact with the porous channels. Other parameters and the like are the same as those of catalyst A.

(70) Reaction results of reference examples 7 and 8 show that, long distance and short distance lead to high selectivity of the methane, and are not conducive to the production of the gasoline fraction.

(71) It is observed from the above table that the structure of the zeolite including the topologies, and the matching of the distance between the metal oxide and the zeolite are crucial and directly affect the selectivity of the gasoline fraction and the light olefins.

(72) Reaction results of reference examples 7 and 8 show that, long distance and short distance lead to high selectivity of the methane, and are not conducive to the production of the gasoline fraction.

(73) It is observed from the above table that the structure of the zeolite including the topologies of MEL, and the matching of the distance between the metal oxide and the zeolite are crucial and directly affect the selectivity of the gasoline fraction and the light olefins.