CN107413348B - Catalyst, preparation method thereof and method for synthesizing isobutanol - Google Patents
Catalyst, preparation method thereof and method for synthesizing isobutanol Download PDFInfo
- Publication number
- CN107413348B CN107413348B CN201710232604.2A CN201710232604A CN107413348B CN 107413348 B CN107413348 B CN 107413348B CN 201710232604 A CN201710232604 A CN 201710232604A CN 107413348 B CN107413348 B CN 107413348B
- Authority
- CN
- China
- Prior art keywords
- catalyst
- carbon material
- graphitized carbon
- isobutanol
- solution
- 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.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/80—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/18—Carbon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/002—Mixed oxides other than spinels, e.g. perovskite
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/15—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively
- C07C29/151—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases
- C07C29/153—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases characterised by the catalyst used
- C07C29/154—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases characterised by the catalyst used containing copper, silver, gold, or compounds thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a preparation method of a catalyst, which comprises the following steps: providing a graphitized carbon material, and performing activation treatment to obtain an activated graphitized carbon material; providing a copper zinc aluminum salt solution and an alkaline solution; dispersing the active graphitized carbon material in water, and simultaneously adding the copper-zinc-aluminum salt solution and an alkaline solution into the water for coprecipitation to obtain a precursor; and carrying out heat treatment on the precursor to obtain the required catalyst. The preparation method of the catalyst has low preparation cost and is suitable for industrial production; the prepared catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and has high CO conversion rate and isobutanol selectivity. The invention also provides a catalyst which is a compound containing copper, zinc oxide and aluminum oxide and formed by taking the activated graphitized carbon material as a carrier. The invention also provides a method for synthesizing isobutanol, which takes hydrogen and carbon monoxide as synthesis gas and utilizes the catalyst to synthesize the isobutanol.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of chemical materials, in particular to a catalyst, a preparation method thereof and a method for synthesizing isobutanol.
[ background of the invention ]
Since the two oil crisis in the 70 s and the importance of environmental protection in countries around the world, it was recognized that the energy and organic synthesis industry could not rely too much on oil, but that the raw material routes and product structures should be adjusted to develop towards diversification of raw materials and products: i.e. oil, coal, gas, and efforts are made to optimize the utilization of these three combustible mineral resources to produce different chemicals and clean fuels.
After many years of exploration, the process for preparing hydrocarbon, alcohol and ether products by using synthesis gas gradually comes into the sight of people. The synthesis gas is a raw material gas with hydrogen and carbon monoxide as main components, has wide sources, can be generated by gasifying solid fuels such as coal or coke and the like, and can also be prepared from light hydrocarbons such as natural gas, naphtha and the like. At present, the process is moving to large-scale industrialization, and a precondition is created for promoting the industrial application of synthesis gas, wherein the research on the preparation of low carbon alcohol is concerned.
The low-carbon mixed alcohol refers to an alcohol mixture of C1-C6. Of the many products of mixed alcohols, isobutanol has a wide range of uses. Such as being used as high-quality power fuel; moreover, the gasoline additive MTBE (methyl tert-butyl Ether) threatening human health can be replaced by utilizing the advantages of high octane number, superior explosion-proof and shock-proof performance and the like; in addition, isobutanol is also a basic organic chemical raw material and can be used for synthesizing rubber, plastics and the like; in addition, isobutanol can also be used as an excellent extracting agent for extracting rare earth metals.
Catalysts are required in the process of preparing isobutanol by synthesis gas, and the currently adopted catalysts comprise modified high-temperature methanol synthesis catalysts, modified low-temperature methanol synthesis catalysts, zirconium-based catalysts and the like. The modified high-temperature methanol synthesis catalyst products mainly comprise methanol, ethanol, normal propyl alcohol and isobutanol, wherein the methanol and the isobutanol are main components, but the reaction conditions are harsh: the temperature is 400-600 ℃, and the pressure is 12-16 Mpa. Compared with a high-temperature methanol synthesis catalyst, the modified low-temperature methanol synthesis catalyst has mild reaction conditions: the temperature is 270-300 ℃, the pressure is 6-8 MPa, the products mainly comprise methanol and isobutanol, but the conversion rate of carbon monoxide is not high, and the selectivity of isobutanol is low. The zirconium-based catalyst has high selectivity of isobutanol, but the preparation raw material is expensive and is not easy to realize industrialization.
[ summary of the invention ]
In order to overcome the technical problems in the prior art, the invention provides a catalyst, a preparation method thereof and a method for synthesizing isobutanol.
The present invention provides a method for preparing a catalyst to solve the above technical problems, which comprises: providing a graphitized carbon material, and performing activation treatment to obtain an activated graphitized carbon material, wherein the carbon content of the graphitized carbon material is more than 99%, and the graphitized carbon content is more than 90%; providing a copper zinc aluminum salt solution and an alkaline solution; dispersing the activated graphitized carbon material in water, taking an aqueous solution in which the activated graphitized carbon material is dispersed as a carrier, simultaneously adding the copper-zinc-aluminum salt solution and an alkaline solution into the carrier for coprecipitation to obtain a precursor, and controlling the adding speeds of the copper-zinc-aluminum salt solution and the alkaline solution to ensure that the coprecipitation is carried out under the condition that the pH value is 5.5-6; wherein the specific surface area of the graphitized carbon material is more than 80m2/g, the particle size is 6-32 μm, the pore volume is 0.4-0.6cm3 g-1, and the pore diameter is 10-15 nm; the mole number of the graphitized carbon material is n1, and the mole numbers of copper, zinc and aluminum in the copper-zinc-aluminum salt solution are n2, n3 and n4, n1: n2: n3: n 4: 10-20: 1-3: 0.5-1.5: 0.4-1.2, respectively; and carrying out heat treatment on the precursor to obtain the required catalyst; the method specifically comprises the following steps: drying the precursor at 60-100 ℃ for 10-20h to obtain a dried product; and roasting the dried product at 400-500 ℃ for 3-5h to obtain the required catalyst.
Preferably, the adding speed of the copper zinc aluminum salt solution and the alkaline solution is controlled, so that the coprecipitation is carried out under the condition that the pH value is 5.0-7.0.
Preferably, the graphitized carbon material is one or a combination of several of mesoporous carbon, graphite, carbon fiber and carbon black. Preferably, the above heat treatment of the precursor to obtain the desired catalyst specifically comprises: drying the precursor at 60-100 ℃ for 10-20h to obtain a dried product; and roasting the dried product at the temperature of 300-500 ℃ for 3-5h to obtain the required catalyst.
Preferably, the activation treatment is to activate the graphitized carbon material by using an acidic solution, and the molar concentration of the acidic solution is 10-20 mol/L; or the activation treatment is to activate the graphitized carbon material by using an alkaline solution, wherein the molar concentration of the alkaline solution is 2-8 mol/L.
Preferably, the activation treatment is specifically: providing an acid solution with the molar concentration of 10-20 mol/L; immersing the graphitized carbon material in an acid solution, and refluxing for 2-4h at 50-90 ℃ to obtain an activated product; and washing the activated product, and drying at 80-120 ℃ for 16-24h to obtain the activated graphitized carbon material.
The invention also provides a catalyst prepared by the preparation method of the catalyst, wherein the catalyst is a compound containing copper, zinc oxide and aluminum oxide and is formed by taking an active graphitized carbon material as a carrier, and is expressed as Cu/ZnO/Al2O3/x％C。
Preferably, the mass fraction of the activated graphitized carbon material in the catalyst is 10 to 50%.
The invention also provides a method for synthesizing isobutanol, which takes hydrogen and carbon monoxide as synthesis gas and utilizes the catalyst to synthesize the isobutanol under the conditions that the reaction temperature is 250-360 ℃ and the pressure is 3-5 Mpa.
Compared with the prior art, the preparation method of the catalyst provided by the invention has the advantages that firstly, the graphitized carbon material and the copper-zinc-aluminum salt solution are used as raw materials, the preparation cost is low, and the preparation method is suitable for industrial production; secondly, the prepared catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and the CO conversion rate and isobutanol selectivity are high; in addition, the prepared catalyst is used for synthesizing isobutanol, and the reaction conditions are mild.
The invention also provides a catalyst, which is a compound containing copper, zinc oxide and aluminum oxide and formed by taking the activated graphitized carbon material as a carrier, and the catalyst is particularly suitable for preparing isobutanol by preparing synthesis gas, and has high CO conversion rate and isobutanol selectivity; and the prepared catalyst is used for synthesizing isobutanol, and the reaction condition is mild.
The invention also provides a method for synthesizing isobutanol, which takes hydrogen and carbon monoxide as synthesis gas and utilizes the catalyst to synthesize the isobutanol under the conditions that the reaction temperature is 250-360 ℃ and the pressure is 3-5 Mpa. Firstly, the reaction conditions are mild, and the CO conversion and isobutanol selectivity are high.
[ description of the drawings ]
FIG. 1 is a schematic flow diagram of a process for preparing a catalyst according to the present invention.
Fig. 2 is a schematic flow chart of step S1 in the method for preparing the catalyst provided by the present invention.
Fig. 3 is a schematic flow chart of step S4 in the method for preparing the catalyst provided by the present invention.
Figure 4 is a schematic flow diagram of a method for synthesizing isobutanol provided by the present invention.
[ detailed description ] embodiments
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example one
As shown in fig. 1, a method for preparing a catalyst includes:
step S1: providing a graphitized carbon material, and performing activation treatment to obtain an activated graphitized carbon material;
step S2: providing a copper zinc aluminum salt solution and an alkaline solution;
step S3: dispersing the active graphitized carbon material in water, and simultaneously adding the copper-zinc-aluminum salt solution and an alkaline solution into the water for coprecipitation to obtain a precursor;
step S4: and carrying out heat treatment on the precursor to obtain the required catalyst.
The steps S1 and S2 may be performed simultaneously or separately, and the order is not limited.
In step S3, the aqueous solution in which the active graphitized carbon material is dispersed is used as a carrier, and the copper zinc aluminum salt solution and the alkaline solution are added at the same time, copper ions, zinc ions, and aluminum ions contained in the copper zinc aluminum salt solution are combined with hydroxide ions in the alkaline solution to form a precipitate, and the precipitate is further combined with the active graphitized carbon material dispersed in water to form a composite.
Then, in step S4, that is, after heat treatment, a catalyst is obtained, which is a composite containing copper, zinc oxide and alumina, and is formed by using an activated graphitized carbon material as a carrier, and may be expressed as Cu/ZnO/Al2O3X% C. Wherein Cu/ZnO/Al2O3As an active material, an activated graphitized carbon material (i.e., C) is used as a carrier, and x% represents the mass fraction of the activated graphitized carbon material in the catalyst. In the present invention, x% is preferably 10 to 50%.
The preparation method of the catalyst provided by the invention has the following advantages:
(1) the graphitized carbon material and the copper-zinc-aluminum salt solution are adopted as raw materials, so that the preparation cost is low, and the method is suitable for industrial production.
(2) The prepared catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and has high CO conversion rate and isobutanol selectivity.
(3) The prepared catalyst is used for synthesizing isobutanol, and the reaction condition is mild.
As further explained herein, Cu/ZnO/Al in the catalyst2O3The active material is easy to agglomerate, so that the activity of the active material is influenced, and the performance of the catalyst is further influenced; the active graphitized carbon material is used as a carrier, so that Cu/ZnO/Al can be effectively relieved2O3The phenomenon of easy agglomeration promotes the dispersion of active components, ensures the activity of active substances to be reflected in the catalyst, and further ensures the performance of the catalyst. The catalyst performance as referred to herein includes conversion, selectivity, and whether or not the reaction conditions are mild.
And the required catalyst is obtained by in-situ compounding in a coprecipitation mode, namely step S3, on the premise that the active graphitized carbon material and the active substance can be well combined, the active substance can be further ensured to be uniformly dispersed. In addition, the prepared catalyst contains the graphitized carbon material, and can promote electron transfer under the action of delocalized large pi bonds of the graphitized carbon material, so that when the catalyst prepared by the preparation method of the catalyst is used for preparing isobutanol by synthesis gas, the CO conversion rate and the isobutanol selectivity can be effectively improved.
In some embodiments, referring to fig. 2, step S1 includes:
step S11: graphitized carbon materials are provided.
Preferably, the carbon content of the graphitized carbon material is greater than 99% and the graphitized carbon content is greater than 90%. The graphitized carbon material can be one or a combination of more of mesoporous carbon, graphite, carbon fiber and carbon black. The graphitized carbon material is preferably graphite, and the conductivity of the graphite is better, so that the CO conversion rate and the isobutanol selectivity can be better ensured. Further, the graphitized carbon material has a specific surface area of more than 80m2Per g, the particle size is 6-32 μm, and the pore volume is 0.4-0.6cm3·g-1The aperture is 10-15 nm. By determining the parameters, the performance of the prepared catalyst can be further ensured.
Step S12: activating the graphitized carbon material with an acidic solution or an alkaline solution.
The activation treatment can destroy the tube wall of the graphitized carbon material to increase the functional groups on the surface of the graphitized carbon material, thereby being favorable for being used as a carrier to load metals.
In some embodiments, the activation treatment is activating the graphitized carbon material by using an alkaline solution, and the molar concentration of the alkaline solution is 2-8 mol/L; among them, potassium hydroxide is commonly used.
In some preferred embodiments, the activation treatment is to activate the graphitized carbon material by using an acidic solution, and the molar concentration of the acidic solution is 10-20 mol/L. Compared with the method for activating the graphitized carbon material by using an alkaline solution, the method for activating the graphitized carbon material by using an acidic solution has the advantages that the surface defects of the activated graphitized carbon material are overcome, the activated graphitized carbon material can be combined with precipitates, the electron transfer of active components in the catalyst is promoted, and the CO conversion rate and the isobutanol selectivity are further ensured. More preferably, the acidic solution is a strong acid, preferably nitric acid or a mixed acid of nitric acid and sulfuric acid. Nitric acid and sulfuric acid have good corrosivity, so that more surface functional groups can be obtained. Wherein, the nitric acid can adopt concentrated nitric acid with the mass fraction of 65%, and the sulfuric acid can adopt concentrated sulfuric acid with the mass fraction of 98%. When a mixed acid of nitric acid and sulfuric acid is used, the volume ratio of the nitric acid to the sulfuric acid is preferably 1 (2-5).
Further, the activation treatment specifically comprises: providing an acid solution with the molar concentration of 10-20 mol/L; immersing the graphitized carbon material in an acid solution, and refluxing for 2-4h at 50-90 ℃ to obtain an activated product; and washing the activated product, and drying at 80-120 ℃ for 16-24h to obtain the activated graphitized carbon material. The activation effect of the graphitized carbon material is ensured by refluxing the acidic solution and further determining the temperature and time.
Step S13: and washing the activated product, and drying at 80-120 ℃ for 16-24h to obtain the activated graphitized carbon material. The washing may be suction filtration or centrifugal filtration, and the like, and is mainly to remove the residual acidic solution, and the obtained activated graphitized carbon material is approximately neutral.
As described earlier, Cu/ZnO/Al in the catalyst2O3As active material, in the active material Cu/ZnO/Al2O3In (1), Cu/ZnO is a bifunctional component. Cu is the main active center and plays a role in activating, dissociating and adsorbing H2The function of (1); ZnO promotes the dispersion of Cu, and has the effects of resisting sulfur poisoning, prolonging the service life of the catalyst and the like; al (Al)2O3Is a structural assistant and plays a role in dispersing active components, preventing the active components from sintering and the like.
In some preferred embodiments, the mole numbers of copper, zinc and aluminum in the copper-zinc-aluminum salt solution are respectively n2、n3、n4，n2:n3:n4(1-3): (0.5-1.5): (0.4-1.2). The molar ratio of copper, zinc and aluminum in the copper-zinc-aluminum salt solution is determined, and the active substance Cu/ZnO/Al in the obtained catalyst is determined2O3Thereby better ensuring the activity of the catalyst. Preferably, n is2:n3:n4(1.5-2.5): 0.8-1.2): 0.6-1); more preferably, n2:n3:n42:1: 0.8. The copper zinc aluminium salt solution may be obtained by dissolving the corresponding soluble salts in water and preferably using the same anion, such as copper nitrate, zinc nitrate and aluminium nitrate, or copper sulphate, zinc sulphate or aluminium sulphate, or copper chloride, zinc chloride and aluminium chloride.
The active graphitized carbon material in the prepared catalyst is used as a carrier, and if the content is too low, the effects of uniformly dispersing active substances, promoting electron transfer and the like cannot be well achieved; if the content is too high, the content of active material is correspondingly low, which affects the activity of the catalyst obtained. Therefore, the catalyst with better catalytic performance can be better ensured to be obtained by determining the mass fraction of the active graphitized carbon material in the catalyst. Wherein, the mass fraction of the activated graphitized carbon material in the catalyst is preferably 10-50%. It will be understood that when the number of moles of copper, zinc and aluminium in the copper-zinc-aluminium salt solution is determined, the catalyst active material Cu/ZnO/Al can be determined2O3The mass of the active graphitized carbon material in the catalyst can be further determined by adjusting the mass of the graphitized carbon material. Therefore, it is preferable that the graphitized carbon material has a molar number n1Then n is1:n2:n3:n4(10-20): (1-3): (0.5-1.5): 0.4-1.2). Preferably, n is1:n2:n3:n4(12-18): (1.5-2.5): (0.8-1.2): 0.6-1). It will be appreciated that the catalyst provided by the present invention is prepared by physical reactions without loss of the components (i.e. carbon, copper, zinc and aluminium) and therefore the number of moles of components in the final catalyst prepared.
In some preferred embodiments, in step S3, the adding speed of the copper zinc aluminum salt solution and the alkaline solution is controlled so that the coprecipitation is performed at a pH of 5.0 to 7.0. It will be appreciated that the copper zinc aluminium salt solution is acidic due to hydrolysis of the metal ions and the alkaline solution is alkaline, both being determined by monitoring the pH during additionThe addition rate and the addition amount of the catalyst are controlled, so that the smooth operation of coprecipitation is ensured and the required reaction product is obtained. Wherein the alkaline solution may be NaOH, KOH, Na2CO3、K2CO3One or more of NaOH solution, KOH solution, NaOH and Na2CO3Mixed solution of (3), KOH and K2CO3The mixed solution of (1). Preferably, the precursor is stirred and washed to neutrality before heat treatment, and generally stirring is needed for 0.5-2h to obtain a uniformly dispersed precursor; the washing may be performed by centrifugal filtration, suction filtration or the like.
Preferably, referring to fig. 3, step S4, namely, performing a heat treatment on the precursor to obtain the desired catalyst, further includes:
step S41: drying the precursor at 60-100 ℃ for 10-20h to obtain a dried product; and
step S42: the dried product is calcined at the temperature of 300-500 ℃ for 3-5h to obtain the required catalyst.
Example two
The invention also provides a catalyst, which is a compound containing copper, zinc oxide and aluminum oxide and formed by taking the activated graphitized carbon material as a carrier, and can be prepared by adopting the preparation method of the catalyst provided in the first embodiment. The catalyst can be expressed as Cu/ZnO/Al2O3X% C. Wherein Cu/ZnO/Al2O3As an active material, an activated graphitized carbon material (i.e., C) is used as a carrier, and x% represents the mass fraction of the activated graphitized carbon material in the catalyst. The catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and has high CO conversion rate and isobutanol selectivity; and the prepared catalyst is used for synthesizing isobutanol, and the reaction condition is mild.
The active graphitized carbon material in the catalyst is used as a carrier, and if the content is too low, the effects of uniformly dispersing active substances, promoting electron transfer and the like cannot be well achieved; if the content is too high, the content of active material is correspondingly low, which affects the activity of the catalyst obtained. Therefore, the catalyst with better catalytic performance can be better ensured to be obtained by determining the mass fraction of the graphitized carbon material in the catalyst. Wherein, the mass fraction of the activated graphitized carbon material in the catalyst is preferably 10-50%. More preferably, the mass fraction of the graphitized carbon material in the catalyst is 20-40%; specifically, the mass fraction of the graphitized carbon material in the catalyst may be 20%, 25%, 30%, 35%, 40%.
Preferably, Cu, ZnO and Al in the catalyst2O3The mole ratio of (1-3) to (0.5-1.5) to (0.4-1.2); thus, the active material Cu/ZnO/Al was determined2O3Thereby better ensuring the activity of the catalyst. More preferably, Cu, ZnO and Al are contained in the catalyst2O3The mole ratio of (1.5-2.5) to (0.8-1.2) to (0.6-1); most preferably Cu, ZnO and Al in the catalyst2O3The ratio of the number of moles of (a) to (b) is 2:1: 0.8.
EXAMPLE III
The invention also provides a method for synthesizing isobutanol, which takes hydrogen and carbon monoxide as synthesis gas and utilizes the catalyst to synthesize the isobutanol, namely utilizes the catalyst provided in the second embodiment to synthesize the isobutanol. Firstly, the catalyst has mild reaction conditions and high CO conversion rate and isobutanol selectivity. The reaction conditions required are: the reaction temperature is 250 ℃ and 360 ℃, and the pressure is 3-5 Mpa. The CO conversion rate can reach 61.14%, and the isobutanol selectivity can reach 17.0%.
Specifically, as shown in fig. 4, the method for synthesizing isobutanol includes:
step T1: reducing the catalyst; placing the catalyst in N2:H21 in an atmosphere of 250-350 ℃ for 2-10 h;
step T2: the isobutanol is obtained by the reaction of the reduced catalyst and the synthesis gas at the temperature of 250 ℃ and 360 ℃ and under the pressure of 3-5 Mpa. The synthesis gas comprises hydrogen and carbon monoxide, and the volume ratio of the hydrogen to the carbon monoxide is (0.5-2.5): 1.
Specific experimental groups are further provided below:
experimental groups 1-1
2g of graphitized mesoporous carbon is weighed, and a proper amount of concentrated nitric acid is taken to immerse the mesoporous carbon, and the mixture is refluxed for 3 hours at the temperature of 60 ℃. And then carrying out suction filtration and washing, drying at 80 ℃ for 12h to obtain active graphitized mesoporous carbon, and dispersing the active graphitized mesoporous carbon in distilled water to obtain a solution A.
Weigh 9.6g Cu (NO)3)2·3H2O、6g Zn(NO3)2·6H2O and 6gAl (NO)3)3·9H2And preparing the O into a mixed solution to obtain a solution B.
Taking 0.5mol/L NaOH solution or preparing 0.5mol/L NaOH solution, and providing or obtaining solution C.
And simultaneously adding the solution B and the solution C into the solution A, carrying out coprecipitation under the conditions that the pH value is 5.0 and the temperature is 25 ℃, and obtaining a precursor after precipitation is finished. Stirring for 0.5h, and washing to be neutral; then drying at 60 ℃ for 10h, and roasting at 300 ℃ for 3h to obtain the catalyst.
It is understood that 9.6g of Cu (NO) is weighed3)2·3H2O、6gZn(NO3)2·6H2O and 6g Al (NO)3)3·9H2Active material Cu/ZnO/Al finally formed in O2O3About 4.98g, the mass fraction of mesoporous carbon in the catalyst is therefore about 2/(2+4.98) ═ 29%.
Synthesis of isobutanol using the prepared catalyst
And (3) catalyst reduction: the catalyst is placed in a fixed bed, N2:H2Under the atmosphere of 3:1, the temperature rise rate of 5 ℃/min is increased to 250 ℃ for reduction for 2 h.
Carrying out reaction by using the reduced catalyst and synthesis gas to obtain isobutanol: the reaction temperature is 250 ℃, the pressure is 3Mpa, and the reaction temperature is H2The synthesis reaction was carried out under the condition that CO was 0.5: 1.
The on-line test of GC9560 gas chromatography shows that the CO conversion is 42.55%, the hydrocarbon content is 12.05%, and the CO content is 12210.56 percent and the selectivity of the total alcohol is 77.39 percent, and the alcohol distribution of methanol, ethanol, isopropanol, normal propyl alcohol, isobutanol and normal butanol in the total alcohol is respectively71.32%, 3.44%, 1.52%, 3.67%, 18.24%, 1.81%, i.e. the selectivity for isobutanol was 14.2%.
Experimental groups 1-2
The differences between experimental groups 1-2 and 1-1 are: weighing 2.5g of graphitized mesoporous carbon to prepare the catalyst; the mass fraction of mesoporous carbon in the catalyst was about 33%.
Finally, the online test is carried out by adopting GC9560 gas chromatography, the conversion rate of CO is 42.36 percent, the hydrocarbon content is 10.85 percent, and the CO content is 10.85 percent29.51% and 74.02% of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 70.69%, 3.51%, 1.41%, 3.56%, 19.05% and 1.78%, respectively, i.e. the selectivity of isobutanol is 14.1%.
Experimental groups 1 to 3
The differences between experimental groups 1-3 and experimental groups 1-1 are: weighing 3g of graphitized mesoporous carbon to prepare the catalyst; the mass fraction of mesoporous carbon in the catalyst was about 38%.
Finally, the online test is carried out by adopting GC9560 gas chromatography, the conversion rate of CO is 40.79 percent, the hydrocarbon content is 12.85 percent, and the CO content is 12.85 percent210.78% and 76.37% of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 71.01%, 3.75%, 1.47%, 3.76%, 18.32% and 1.69%, respectively, i.e. the selectivity of isobutanol is 13.9%.
Experimental groups 1 to 4
The differences between experimental groups 1-4 and experimental groups 1-1 are: weighing 1.5g of graphitized mesoporous carbon to prepare the catalyst; the mass fraction of mesoporous carbon in the catalyst was about 23%.
Finally, the online test is carried out by adopting GC9560 gas chromatography, the conversion rate of CO is 39.16 percent, the hydrocarbon content is 13.47 percent, and the CO content is 13.47 percent211.85 percent and total alcohol selectivity of 74.68 percent, and the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 72.25 percent, 3.68 percent, 1.69 percent, 3.91 percent, 16.72 percent and 1.75 percent respectively, namely the selectivity of the isobutanol is 12.5 percent.
The experimental conditions and experimental results of experimental groups 1-1, 1-2, 1-3, 1-4 are shown in Table 1. As shown in table 1, in each of the experimental groups 1-1, 1-2, 1-3, and 1-4, the catalyst was prepared using mesoporous carbon, but the amount of mesoporous carbon was different, and it was found from the experimental results that when the mass fraction of mesoporous carbon in the experimental group 1-1, that is, the catalyst was 29%, the CO conversion rate and the isobutanol selectivity were high, 42.55% and 14.2%, respectively.
TABLE 1
Experimental group 2-1
Weighing 2.5g of graphite, taking a proper amount of mixed acid of concentrated nitric acid and concentrated sulfuric acid (the volume ratio is 1:3), immersing the graphite properly, refluxing for 2h at 80 ℃, filtering, washing, drying for 10h at 80 ℃ to obtain active graphite, and dispersing the active graphite in distilled water to obtain a solution A.
Weigh 9.0g Cu (NO)3)2·3H2O、6.5g Zn(NO3)2·6H2O and 6.5g Al (NO)3)3·9H2And preparing the O into a mixed solution to obtain a solution B.
Taking 1mol/L NaOH/Na2CO3Mixing alkali solution, or preparing 1mol/L NaOH/Na2CO3And mixing the alkali solution to provide or obtain a solution C.
And simultaneously adding the solution B and the solution C into the solution A, carrying out coprecipitation under the conditions that the pH value is 5.5 and the temperature is 30 ℃, and obtaining a precursor after precipitation is finished. Stirring for 1h, and washing to be neutral; then drying at 80 ℃ for 12h, and roasting at 400 ℃ for 3h to obtain the catalyst.
It is understood that 9.0g of Cu (NO) is weighed3)2·3H2O、6.5gZn(NO3)2·6H2O and 6.5gAl (NO)3)3·9H2Active material Cu/ZnO/Al finally formed in O2O3About 5.02g, the mass fraction of graphite in the catalyst was about 2.5/(2.5+5.02) — 33%.
Synthesis of isobutanol using the prepared catalyst
And (3) catalyst reduction: the catalyst is placed in the solidIn fixed bed, N2:H2Under the atmosphere of 3.5:1, the temperature rise rate of 5 ℃/min is increased to 280 ℃ for reduction for 5 h.
Carrying out reaction by using the reduced catalyst and synthesis gas to obtain isobutanol: the reaction temperature is 280 ℃, the pressure is 4Mpa, and the reaction temperature is H2The synthesis reaction is carried out under the condition that CO is 1: 1.
The on-line test of GC9560 gas chromatography shows that the CO conversion rate is 55.25%, the hydrocarbon content is 11.23%, and the CO content is28.72 percent and 80.05 percent of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is respectively 68.26 percent, 3.98 percent, 1.74 percent, 3.24 percent, 21.22 percent and 1.56 percent, namely the selectivity of the isobutanol is 17.0 percent.
Experimental groups 2-2
The difference between the experimental group 2-2 and the experimental group 2-1 is: weighing 3g of graphite to prepare a catalyst; the mass fraction of graphite in the catalyst was about 37%.
The on-line test of GC9560 gas chromatography shows that the CO conversion rate is 54.28%, the hydrocarbon content is 11.50%, and the CO content is28.96 percent and 79.54 percent of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 69.13 percent, 3.94 percent, 1.68 percent, 3.16 percent, 21.04 percent and 1.05 percent respectively, namely the selectivity of the isobutanol is 16.7 percent.
Experimental groups 2 to 3
The differences between the experimental groups 2-3 and 2-1 are: weighing 3.5g of graphite for preparing the catalyst; the mass fraction of graphite in the catalyst was about 41%.
The on-line test of GC9560 gas chromatography shows that the CO conversion rate is 52.14%, the hydrocarbon content is 12.52%, and the CO content is 12.52%29.45 percent and the selectivity of the total alcohol is 78.03 percent, and the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 69.41 percent, 3.87 percent, 1.75 percent, 3.45 percent, 20.42 percent and 1.10 percent respectively, namely the selectivity of the isobutanol is 15.9 percent.
Experimental groups 2 to 4
The differences between experimental groups 2-4 and 2-1 are: weighing 2g of graphite to prepare a catalyst; the mass fraction of graphite in the catalyst was about 28%.
On-line testing was performed by GC9560 gas chromatography with a CO conversion of 53.68%, hydrocarbons of 11.61%, CO29.13 percent and 79.26 percent of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 70.02 percent, 4.12 percent, 1.62 percent, 3.18 percent, 20.75 percent and 1.11 percent respectively, namely the selectivity of the isobutanol is 16.4 percent.
The experimental conditions and experimental results of experimental groups 2-1, 2-2, 2-3, and 2-4 are shown in Table 2. As shown in table 2, in each of the experimental groups 2-1, 2-2, 2-3, and 2-4, the catalyst was prepared using graphite, but the amount of graphite used was different, and it was found from the experimental results that when the mass fraction of graphite in the experimental group 2-1, that is, the catalyst was 33%, the CO conversion rate and the isobutanol selectivity were high, 55.25% and 17.0%, respectively.
TABLE 2
Experimental group 3-1
Weighing 2g of carbon fiber, taking a proper amount of mixed acid of concentrated nitric acid and concentrated sulfuric acid (the volume ratio is 1:4), immersing the carbon fiber, refluxing for 2h at 100 ℃, filtering, washing, drying for 12h at 90 ℃ to obtain activated carbon fiber, and dispersing the activated carbon fiber in distilled water to obtain a solution A.
Weigh 10g of Cu (NO)3)2·3H2O、7.8g Zn(NO3)2·6H2O and 7.8gAl (NO)3)3·9H2And preparing the O into a mixed solution to obtain a solution B.
Taking 1mol/L KOH solution, or preparing 1mol/L KOH solution, namely providing or obtaining solution C.
And simultaneously adding the solution B and the solution C into the solution A, carrying out coprecipitation under the conditions that the pH value is 6 and the temperature is 35 ℃, and obtaining a precursor after the precipitation is finished. Stirring for 1.5h, and washing to be neutral; then drying at 80 ℃ for 18h, and roasting at 500 ℃ for 3h to obtain the catalyst.
It is understood that 10g of Cu (NO) is weighed3)2·3H2O、7.8gZn(NO3)2·6H2O and 7.8g Al (NO)3)3·9H2Active material Cu/ZnO/Al finally formed in O2O3About 5.82g, the mass fraction of carbon fibres in the catalyst is therefore about 2/(2+5.82) ═ 26%.
Synthesis of isobutanol using the prepared catalyst
And (3) catalyst reduction: the catalyst is placed in a fixed bed, N2:H2Under the atmosphere of 4:1, the temperature rise rate of 5 ℃/min is increased to 300 ℃ for reduction for 8 h.
Carrying out reaction by using the reduced catalyst and synthesis gas to obtain isobutanol: the reaction temperature is 300 ℃, the pressure is 5Mpa, and the reaction temperature is H2The synthesis reaction is carried out under the condition that CO is 2: 1.
The on-line test of GC9560 gas chromatography shows that the CO conversion is 52.11%, the hydrocarbon content is 13.54%, and the CO content is 13213.21 percent and the selectivity of the total alcohol is 73.25 percent, and the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 72.41 percent, 2.55 percent, 2.04 percent, 3.21 percent, 18.01 percent and 1.78 percent respectively, namely the selectivity of the isobutanol is 13.2 percent.
Experimental group 3-2
The difference between the experimental group 3-2 and the experimental group 3-1 is: weighing 1.5g of carbon fiber to prepare a catalyst; the mass fraction of carbon fibers in the catalyst is about 20%.
The on-line test of GC9560 gas chromatography shows that the CO conversion is 50.67%, the hydrocarbon content is 13.76%, and the CO content is 13214.04 percent and total alcohol selectivity 72.20 percent, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 71.78 percent, 2.77 percent, 2.25 percent, 3.29 percent, 17.97 percent and 1.94 percent respectively, namely the selectivity of the isobutanol is 13.0 percent.
Experimental groups 3 to 3
The differences between the experimental group 3-3 and the experimental group 3-1 are: weighing 2.5g of carbon fiber to prepare a catalyst; the mass fraction of carbon fibers in the catalyst is about 30%.
On-line testing was performed using GC9560 gas chromatography with a CO conversion of 51.45% and hydrocarbons of 13.23％、CO213.99 percent and total alcohol selectivity of 72.78 percent, and the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 71.97 percent, 2.71 percent, 1.98 percent, 3.34 percent, 18.03 percent and 1.97 percent respectively, namely the selectivity of isobutanol is 13.1 percent.
Experimental groups 3 to 4
The differences between the experimental groups 3-4 and 3-1 are: weighing 3g of carbon fiber to prepare a catalyst; the mass fraction of carbon fibers in the catalyst was about 34%.
The on-line test of GC9560 gas chromatography shows that the CO conversion rate is 49.94%, the hydrocarbon content is 14.05%, and the CO content is 14.05%214.27% and total alcohol selectivity 71.68%, and the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol, and n-butanol in the total alcohol is 72.12%, 2.69%, 2.31%, 3.48%, 17.44%, and 1.96%, respectively, i.e., the selectivity of isobutanol is 12.5%.
The experimental conditions and experimental results of experimental groups 3-1, 3-2, 3-3, and 3-4 are shown in Table 3. As shown in table 3, in each of the experimental groups 3-1, 3-2, 3-3, and 3-4, the catalyst was prepared using carbon fibers, but the amount of the carbon fibers was different, and it was found from the experimental results that the CO conversion and the isobutanol selectivity were high at 52.11% and 13.2% when the mass fraction of the carbon fibers in the catalyst of the experimental group 3-1 was 25%.
TABLE 3
Experimental group 4-1
Weighing 2.5g of graphitized carbon black, taking a proper amount of concentrated nitric acid to immerse the carbon black, refluxing for 3h at 70 ℃, performing suction filtration and washing, drying for 20h at 100 ℃ to obtain active carbon black, and dispersing the active carbon black in distilled water to obtain a solution A.
Weigh 9.2g Cu (NO)3)2·3H2O、5.9g Zn(NO3)2·6H2O and 5.5g Al (NO)3)3·9H2And preparing the O into a mixed solution to obtain a solution B.
2mol/L of KO is takenH/K2CO3Mixed alkali solution, or 2mol/L KOH/K2CO3And mixing the alkali solution to provide or obtain a solution C.
And simultaneously adding the solution B and the solution C into the solution A, carrying out coprecipitation under the conditions that the pH value is 7.0 and the temperature is 40 ℃, and obtaining a precursor after precipitation is finished. Stirring for 2h, and washing to be neutral; then drying the catalyst at 90 ℃ for 24h, and roasting the catalyst at 300 ℃ for 3h to obtain the catalyst.
It is understood that 9.2g of Cu (NO) is weighed3)2·3H2O、5.9gZn(NO3)2·6H2O and 5.5g Al (NO)3)3·9H2Active material Cu/ZnO/Al finally formed in O2O3About 4.78g, the mass fraction of carbon black in the catalyst was therefore about 2.5/(2.5+4.78) — 34%.
Synthesis of isobutanol using the prepared catalyst
And (3) catalyst reduction: the catalyst is placed in a fixed bed, N2:H2Under the atmosphere of 4.5:1, the temperature rise rate of 5 ℃/min is increased to 360 ℃ for reduction for 10 h.
Carrying out reaction by using the reduced catalyst and synthesis gas to obtain isobutanol: the reaction temperature is 360 ℃, the pressure is 3Mpa, and H is2The synthesis reaction is carried out under the condition that CO is 2.5: 1.
The on-line test of GC9560 gas chromatography shows that the CO conversion is 61.14%, the hydrocarbon content is 18.05%, and the CO content is 18.05%210.15% and 71.80% of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is 69.99%, 3.17%, 1.82%, 2.79%, 20.56% and 1.67%, respectively, i.e. the selectivity of isobutanol is 14.8%.
Experimental group 4-2
The difference between the experimental group 4-2 and the experimental group 4-1 is: 3g of carbon black is weighed for preparation of the catalyst; the mass fraction of carbon black in the catalyst was about 39%.
The on-line test of GC9560 gas chromatography shows that the CO conversion is 60.53%, the hydrocarbon content is 18.75%, and the CO content is 18.75%211.12 percent of total alcohol selectivity 70.13 percent, methanol, ethanol in the total alcohol,The alcohol distribution of isopropanol, n-propanol, isobutanol and n-butanol was 70.41%, 3.54%, 1.96%, 2.93%, 19.25% and 1.91%, respectively, i.e., the selectivity for isobutanol was 13.5%.
Experimental groups 4 to 3
The differences between the experimental group 4-3 and the experimental group 4-1 are: 3.5g of carbon black is weighed for the preparation of the catalyst; the mass fraction of carbon black in the catalyst was about 42%.
The on-line test of GC9560 gas chromatography shows that the CO conversion rate is 59.42 percent, the hydrocarbon content is 20.12 percent, and the CO content is 20.12 percent212.76 percent and the selectivity of the total alcohol is 67.12 percent, and the alcohol distribution of the methanol, the ethanol, the isopropanol, the n-propanol, the isobutanol and the n-butanol in the total alcohol is 70.52 percent, 3.71 percent, 1.94 percent, 3.04 percent, 18.77 percent and 2.02 percent respectively, namely the selectivity of the isobutanol is 12.6 percent.
Experimental groups 4 to 4
The differences between the experimental group 4-4 and the experimental group 4-1 are: weighing 2g of carbon black to prepare a catalyst; the mass fraction of carbon black in the catalyst was about 29%.
On-line testing was performed by GC9560 gas chromatography with a CO conversion of 59.13%, hydrocarbons of 20.71%, CO212.88 percent and 66.41 percent of total alcohol selectivity, wherein the alcohol distribution of methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol in the total alcohol is respectively 70.48 percent, 3.83 percent, 2.10 percent, 3.24 percent, 18.37 percent and 1.98 percent, namely the selectivity of the isobutanol is 12.2 percent.
The experimental conditions and the experimental results of the experimental groups 4-1, 4-2, 4-3, and 4-4 are shown in Table 4. As shown in Table 4, in each of the experimental groups 4-1, 4-2, 4-3, and 4-4, the catalyst was prepared using carbon black, but the amount of carbon black used was different, and it was found from the experimental results that the CO conversion and the isobutanol selectivity were high at 61.14% and 14.8% when the mass fraction of carbon black in the experimental group 4-1, that is, the catalyst was 34%.
TABLE 4
In addition, comparative analysis was performed on experimental groups that were experimented with different graphitized carbon materials. Here, only one group with the best test results was compared, i.e., the experimental groups 1-1, 2-1, 3-1, and 4-1. The experimental conditions and the experimental results of the experimental groups 1-1, 2-1, 3-1, 4-1 are shown in Table 5.
TABLE 5
Comparing all experimental groups, the catalyst prepared by using graphite has the highest selectivity of isobutanol, which can reach 17.0 percent when being used for synthesizing isobutanol; when the catalyst prepared by using the carbon black is used for synthesizing isobutanol, the CO conversion rate is highest and can reach 61.14%. Moreover, when the catalysts prepared from different types of graphitized carbon materials are used for synthesizing isobutanol, the preferable reduction conditions and synthesis conditions of the catalysts are different, and specifically, the conditions are shown in table 5.
Compared with the prior art, the preparation method of the catalyst provided by the invention comprises the following steps: providing a graphitized carbon material, and performing activation treatment to obtain an activated graphitized carbon material; providing a copper zinc aluminum salt solution and an alkaline solution; dispersing the active graphitized carbon material in water, and simultaneously adding the copper-zinc-aluminum salt solution and an alkaline solution into the water for coprecipitation to obtain a precursor; and carrying out heat treatment on the precursor to obtain the required catalyst. Firstly, the graphitized carbon material and the copper-zinc-aluminum salt solution are adopted as raw materials, so that the preparation cost is low, and the method is suitable for industrial production; secondly, the prepared catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and the CO conversion rate and isobutanol selectivity are high; in addition, the prepared catalyst is used for synthesizing isobutanol, and the reaction conditions are mild.
Further, the adding speed of the copper zinc aluminum salt solution and the alkaline solution is controlled, so that the coprecipitation is carried out under the condition that the pH value is 5.0-7.0. The adding speed and the adding amount of the pH value and the pH value can be determined by monitoring the pH value in the adding process, so that the smooth proceeding of the coprecipitation is ensured and the required reaction product is obtained.
Further, the carbon content of the graphitized carbon material is more than 99%, and the graphitized carbon content is more than 90%. Therefore, the graphitization degree and the effective quality of the graphitized carbon material can be well ensured, and the performance of the catalyst is ensured.
Preferably, the graphitized carbon material has a mole number n1The mole numbers of copper, zinc and aluminum in the copper-zinc-aluminum salt solution are respectively n2、n3、n4，n1:n2:n3:n4(10-20): (1-3): (0.5-1.5): 0.4-1.2). The molar ratio of copper, zinc and aluminum in the copper-zinc-aluminum salt solution is determined, and the active substance Cu/ZnO/Al in the obtained catalyst is determined2O3Thereby better ensuring the activity of the catalyst. The mass fraction of the active graphitized carbon material in the catalyst can be determined by determining the mole number of the graphitized carbon material, so that the catalyst with better catalytic performance can be better ensured to be obtained.
Preferably, the activation treatment is to activate the graphitized carbon material by using an acidic solution, and the molar concentration of the acidic solution is 10-20 mol/L; or the activation treatment is to activate the graphitized carbon material by using an alkaline solution, wherein the molar concentration of the alkaline solution is 2-8 mol/L. Thus, the activation degree can be ensured, wherein preferably, the graphitized carbon material is activated by utilizing an acid solution, the obtained activated graphitized carbon material has defects on the surface, and can be combined with precipitates to promote the electron transfer of active components in the catalyst, so that the CO conversion rate and the isobutanol selectivity are ensured.
Preferably, the activation treatment is specifically: providing an acid solution with the molar concentration of 10-20 mol/L; immersing the graphitized carbon material in an acid solution, and refluxing for 2-4h at 50-90 ℃ to obtain an activated product; and washing the activated product, and drying at 80-120 ℃ for 16-24h to obtain the activated graphitized carbon material. The activation effect of the graphitized carbon material is ensured by refluxing the acidic solution and further determining the temperature and time.
The invention also provides a catalyst which is a compound containing copper, zinc oxide and aluminum oxide and formed by taking the activated graphitized carbon material as a carrier, and a surfaceShown as Cu/ZnO/Al2O3X% C. The catalyst is particularly suitable for preparing synthesis gas to prepare isobutanol, and has high CO conversion rate and isobutanol selectivity; and the prepared catalyst is used for synthesizing isobutanol, and the reaction condition is mild.
Further, the mass fraction of the active graphitized carbon material in the catalyst is 10-50%. The active graphitized carbon material in the prepared catalyst is used as a carrier, and if the content is too low, the effects of uniformly dispersing active substances, promoting electron transfer and the like cannot be well achieved; if the content is too high, the content of active material is correspondingly low, which affects the activity of the catalyst obtained. Therefore, the catalyst with better catalytic performance can be better ensured to be obtained by determining the mass fraction of the active graphitized carbon material in the catalyst.
The invention also provides a method for synthesizing isobutanol, which takes hydrogen and carbon monoxide as synthesis gas and utilizes the catalyst to synthesize the isobutanol under the conditions that the reaction temperature is 250-360 ℃ and the pressure is 3-5 Mpa. Firstly, the reaction conditions are mild, and the CO conversion and isobutanol selectivity are high.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit of the present invention are intended to be included within the scope of the present invention.
Claims (6)
1. A method for preparing a catalyst, which is characterized by comprising the following steps: the method comprises the following steps: providing a graphitized carbon material, and performing activation treatment to obtain an activated graphitized carbon material, wherein the carbon content of the graphitized carbon material is more than 99%, and the graphitized carbon content is more than 90%; providing a copper zinc aluminum salt solution and an alkaline solution; dispersing the active graphitized carbon material in water, taking an aqueous solution in which the active graphitized carbon material is dispersed as a carrier, simultaneously adding the copper-zinc-aluminum salt solution and an alkaline solution into the carrier for coprecipitation to obtain a precursor, and controlling the adding speeds of the copper-zinc-aluminum salt solution and the alkaline solution to ensure that the coprecipitation is carried out under the condition that the pH value is 5.5-6; wherein the graphitized carbon material has a specific surface area of more than 80m2Per g, the particle size is 6-32 μm, and the pore volume is 0.4-0.6cm3·g-1The aperture is 10-15 nm; the graphitized carbon material has a molar number n1The mole numbers of copper, zinc and aluminum in the copper-zinc-aluminum salt solution are respectively n2、n3、n4，n1∶n2∶n3∶n4(10-20) to (1-3) to (0.5-1.5) to (0.4-1.2); and
carrying out heat treatment on the precursor to obtain a required catalyst; the method specifically comprises the following steps:
drying the precursor at 60-100 ℃ for 10-20h to obtain a dried product; and
roasting the dried product at 400-500 ℃ for 3-5h to obtain the required catalyst; the activation treatment is to activate the graphitized carbon material by utilizing an acid solution, wherein the molar concentration of the acid solution is 10-20 mol/L; the activation treatment specifically comprises the following steps: providing an acid solution with the molar concentration of 10-20 mol/L; immersing the graphitized carbon material in an acid solution, and refluxing for 2-4h at 50-90 ℃ to obtain an activated product; and washing the activated product, and drying at 80-120 ℃ for 16-24h to obtain the activated graphitized carbon material.
2. A process for preparing a catalyst as claimed in claim 1, characterized in that: the graphitized carbon material is one or a combination of several of mesoporous carbon, graphite, carbon fiber and carbon black.
3. A process for preparing a catalyst as claimed in claim 1, characterized in that: the acid solution is nitric acid or mixed acid of nitric acid and sulfuric acid.
4. A catalyst obtained by the method for producing a catalyst according to any one of claims 1 to 3, wherein: the catalyst is a compound containing copper, zinc oxide and aluminum oxide and formed by taking an active graphitized carbon material as a carrier, and is expressed as Cu/ZnO/Al2O3/x％C。
5. The catalyst of claim 4, wherein: the mass fraction of the active graphitized carbon material in the catalyst is 10-50%.
6. A method for synthesizing isobutanol, which is characterized by comprising the following steps: the isobutanol is synthesized by using hydrogen and carbon monoxide as synthesis gas and the catalyst in the claim 4 under the conditions that the reaction temperature is 250-360 ℃ and the pressure is 3-5 Mpa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710232604.2A CN107413348B (en) | 2017-04-11 | 2017-04-11 | Catalyst, preparation method thereof and method for synthesizing isobutanol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710232604.2A CN107413348B (en) | 2017-04-11 | 2017-04-11 | Catalyst, preparation method thereof and method for synthesizing isobutanol |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107413348A CN107413348A (en) | 2017-12-01 |
| CN107413348B true CN107413348B (en) | 2020-11-03 |
Family
ID=60423459
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710232604.2A Active CN107413348B (en) | 2017-04-11 | 2017-04-11 | Catalyst, preparation method thereof and method for synthesizing isobutanol |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107413348B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112452332A (en) * | 2020-10-27 | 2021-03-09 | 安徽华塑股份有限公司 | Micro-nano copper-based high-activity catalyst and preparation method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102814160A (en) * | 2012-08-20 | 2012-12-12 | 西南化工研究设计院有限公司 | Cleaning agent for removing iron carbonyl and nickel carbonyl in synthesis gas and preparation method and application of cleaning agent |
| CN103691442A (en) * | 2013-12-03 | 2014-04-02 | 辽宁石油化工大学 | Catalyst for synthesis of isobutanol from synthesis gas and preparation method of catalyst |
| CN104056629A (en) * | 2014-06-17 | 2014-09-24 | 中国天辰工程有限公司 | Catalyst used in preparation of low-carbon alcohol by synthesis gas, as well as preparation method and application of catalyst |
| CN104069863A (en) * | 2014-07-09 | 2014-10-01 | 太原理工大学 | Aluminum-copper-zinc catalyst for preparing pentane from slurry bed syngas and preparation and application method of aluminum-copper-zinc catalyst |
| CN104549283A (en) * | 2014-12-15 | 2015-04-29 | 天津大学 | Carbon fiber compound nano copper cobalt alloy catalyst for low-carbon alcohol synthesis and preparation method of catalyst |
| CN105772000A (en) * | 2014-12-16 | 2016-07-20 | 中国科学院兰州化学物理研究所 | Graphene oxide promoted copper-based methanol synthesis catalyst and preparation method thereof |
| CN106179356A (en) * | 2015-05-07 | 2016-12-07 | 中国石油化工股份有限公司 | A kind of for CO2cuZnAl catalyst of preparing methanol by hydrogenation and preparation method thereof |
-
2017
- 2017-04-11 CN CN201710232604.2A patent/CN107413348B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102814160A (en) * | 2012-08-20 | 2012-12-12 | 西南化工研究设计院有限公司 | Cleaning agent for removing iron carbonyl and nickel carbonyl in synthesis gas and preparation method and application of cleaning agent |
| CN103691442A (en) * | 2013-12-03 | 2014-04-02 | 辽宁石油化工大学 | Catalyst for synthesis of isobutanol from synthesis gas and preparation method of catalyst |
| CN104056629A (en) * | 2014-06-17 | 2014-09-24 | 中国天辰工程有限公司 | Catalyst used in preparation of low-carbon alcohol by synthesis gas, as well as preparation method and application of catalyst |
| CN104069863A (en) * | 2014-07-09 | 2014-10-01 | 太原理工大学 | Aluminum-copper-zinc catalyst for preparing pentane from slurry bed syngas and preparation and application method of aluminum-copper-zinc catalyst |
| CN104549283A (en) * | 2014-12-15 | 2015-04-29 | 天津大学 | Carbon fiber compound nano copper cobalt alloy catalyst for low-carbon alcohol synthesis and preparation method of catalyst |
| CN105772000A (en) * | 2014-12-16 | 2016-07-20 | 中国科学院兰州化学物理研究所 | Graphene oxide promoted copper-based methanol synthesis catalyst and preparation method thereof |
| CN106179356A (en) * | 2015-05-07 | 2016-12-07 | 中国石油化工股份有限公司 | A kind of for CO2cuZnAl catalyst of preparing methanol by hydrogenation and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| "Highly active CNT-promoted Cu–ZnO–Al2O3 catalyst for methanol synthesis from H2/CO/CO2";Xin Dong et al.;《Catalysis Letters》;20030228;第85卷(第3-4期);第238页第2.1节、第241页表1 * |
| "高性能纳米碳材料改性Cu/ZnO/Al2O3甲醇水蒸汽重整制氢催化剂";张新荣 等;《高等学校化学学报》;20041115;第25卷(第11期);第2125、2127页 * |
| 张新荣 等."高性能纳米碳材料改性Cu/ZnO/Al2O3甲醇水蒸汽重整制氢催化剂".《高等学校化学学报》.2004,第25卷(第11期),第2125、2127页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107413348A (en) | 2017-12-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103007985B (en) | Catalyst for converting alcohols and ethers into aromatic hydrocarbons as well as preparation method and use method thereof | |
| CN103084178B (en) | Copper-contained hydrotalcite-based catalyst for preparing mixed alcohol by using synthesis gas as well as preparation method and application thereof | |
| CN102921426B (en) | Catalyst for catalytic conversion of biological cellulose and preparation method and applications of catalyst | |
| CN109360993A (en) | A kind of synthetic method for the Fe-N/C-20 adulterating iron atom using ZIF-8 as substrate | |
| CN113145155A (en) | Nitrogen-doped carbon-coated nickel catalyst applied to assembly of bioethanol to synthesize high-carbon alcohol and preparation method thereof | |
| CN112403526B (en) | Ce-MOF/Bi2MoO6Heterojunction photocatalyst and preparation method and application thereof | |
| CN103599788B (en) | A kind of cobalt-base catalyst for CO hydrogenation and its preparation method and application | |
| CN108404918A (en) | Tumer ester through hydrogenation produces the copper zinc SiO 2 catalyst and preparation method thereof of ethyl alcohol | |
| CN103611540B (en) | A kind of Catalysts and its preparation method for CO hydrogenation and application | |
| CN102441386B (en) | Novel Fischer Tropsch synthesis method | |
| CN105013486A (en) | Preparation method and applications of core-shell structured Fe3O4@C catalyst used for Fischer-Tropsch synthesis | |
| CN110215927A (en) | A kind of preparation method of the support type catalyst of phosphatizing nickel of high dispersive | |
| CN103589446B (en) | A kind of method of iron-based liquid hydrocarbon | |
| CN108097332B (en) | Low-metamorphic coal-zirconium-based catalyst and preparation method and application thereof | |
| CN107413348B (en) | Catalyst, preparation method thereof and method for synthesizing isobutanol | |
| CN108816227A (en) | Derivative carried copper-base catalyst of metal framework and preparation method thereof | |
| CN103143352A (en) | Preparation method of supported rhodium catalyst taking TiO2 as carrier and CeO2 as cocatalyst and application thereof | |
| CN104128186B (en) | For being prepared the Catalysts and its preparation method of low-carbon alcohols by synthesis gas | |
| CN103623828B (en) | A kind of synthesizing liquid hydrocarbon cobalt-base catalyst and its preparation method and application | |
| CN105642289A (en) | Preparation method of catalyst for complete methanation of syngas | |
| CN104248953A (en) | Catalyst for preparation of ethanol by acetate hydrogenation and preparation method thereof | |
| CN103611574A (en) | Preparation method of catalyst containing benzotriazole and derivatives thereof | |
| CN104148078A (en) | Catalyst for preparing low-carbon alcohol from biomass synthesis gas and preparation method of catalyst | |
| CN113292519A (en) | Magnetic gold-cobalt composite catalyst and preparation method and application thereof | |
| CN109908908A (en) | A kind of base metal preparing hydrogen by reforming methanol catalyst and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |