Composite catalyst and preparation method thereof, and method for producing olefins by dehydrating alcohol

Abstract

The present invention relates to the technical field of alcohol dehydration, and in particular to a composite catalyst and a preparation method thereof, as well as a method for preparing olefins by dehydrating alcohol, the composite catalyst comprising a main component ZrO2, an alkaline earth metal oxide, and a transition metal oxide; wherein, in the composite catalyst, a pore volume with a pore size within the range of 1.7-2.6 nm accounts for more than 60% of the total pore volume of the composite catalyst; relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.05-8 parts by weight; and the transition metal oxide is 0.08-10 parts by weight. The present invention, by introducing alkaline earth metal oxide and transition metal oxide into a ZrO2-based catalyst, can form an unbalanced charge site on the surface of the composite oxide while improving the alkalinity of the ZrO2-based catalyst, thereby forming a new catalyst surface acid center, which is conducive to improving the catalytic performance of the composite catalyst and improving the selectivity of alpha-olefins in the alcohol dehydration reaction.

Description

Technical Field

[0001] The present invention relates to the technical field of alcohol dehydration, and in particular to a composite catalyst and a preparation method thereof, as well as a method for preparing olefins by dehydrating alcohol. Background Art

[0002] The alcohol dehydration method for preparing α-olefins offers a competitive synthetic route with a simple process, mild reaction conditions, high product purity and ease of separation, a relatively clean production process, and low energy consumption during the distillation process. Alcohol dehydration catalysts can be divided into two categories. One is redox catalysts, which have metal ions with redox properties on their surfaces. During adsorption and activation, they produce active free radical intermediates, resulting in numerous side reactions, low selectivity for the target product, and difficulty in product separation. The other is acid-base bifunctional catalysts, which possess both acidic and basic sites on their surfaces and act synergistically with the reactants, exhibiting improved activity, selectivity, and a longer service life. They possess unique catalytic properties in dehydration reactions. Solid oxide acid-base bifunctional catalysts are widely used in reactions such as alcohol dehydration, catalytic hydrogenation, olefin isomerization, olefin hydrogenation, polymerization, and oxidation.

[0003] CN 108126704 A discloses a cerium-iron-zirconium composite oxide catalyst, its preparation method, and its application. The cerium-iron-zirconium composite oxide catalyst is a solid solution catalyst composed of cerium oxide, iron oxide, and zirconium oxide, with the molar ratio of the various metals being 1-30:30-70:30-70%. The invention describes the cerium-iron-zirconium composite oxide as a catalyst for the direct synthesis of dimethyl carbonate from CO2 and CH3OH. However, the methanol conversion rate of this catalyst in the methanol-to-dimethyl carbonate reaction is only 0.12-2.88%.

[0004] US20210039077A1 discloses a bimetallic mesoporous silicate catalyst and its application in alcohol dehydration. A first transition metal M and a second transition metal M' are doped into the silicate, wherein M and M' are selected from Zr, Nb and W, so that M and M' replace Si atoms. The pore size of the catalyst is in the range of 7nm to 10nm. The conditions used for the alcohol dehydration reaction in this invention are mild (low temperature and normal pressure), and the bimetallic silicate catalyst is environmentally friendly (non-toxic and non-corrosive); the catalyst is used to study the dehydration of ethanol, propanol, butanol, nonanol, glycerol and sugar alcohols such as sorbitol and xylitol, and the reaction generates a variety of dehydration products, such as olefins, ethers, ketones, enols, etc., that is, the selectivity of α-olefins is low, and there are side reactions such as dehydrogenation during the catalytic reaction.

[0005] In summary, the alcohol dehydration catalysts in the existing technology have many disadvantages, such as short life, low product selectivity, many side reactions, easy carbon deposition and deactivation, and complex preparation methods, which lead to reduced catalytic activity and thus limit their application in industrial production. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problems of alcohol dehydration catalysts in the prior art, such as short life, low product selectivity, multiple side reactions, easy carbon deposition and deactivation, and complicated preparation methods, and to provide a composite catalyst and a preparation method thereof, as well as a method for dehydrating alcohols to produce olefins.

[0007] In order to achieve the above object, the first aspect of the present invention provides a composite catalyst, the composite catalyst comprising a main component ZrO2, an alkaline earth metal oxide and a transition metal oxide, wherein the pore volume of the composite catalyst having a pore diameter in the range of 1.7-2.6 nm accounts for more than 60% of the total pore volume of the composite catalyst;

[0008] Relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.05-8 parts by weight; the transition metal oxide is 0.08-10 parts by weight; wherein the transition metal oxide is selected from one of Group VIB, VIII, IB, and IIB metal oxides.

[0009] A second aspect of the present invention provides a method for preparing a composite catalyst, comprising: mixing a zirconium source, an alkaline earth metal salt, and a transition metal salt in a solvent at a molar ratio of 1:0.0003-0.2:0.0001-0.02 to obtain a mixed solution; then adding a precipitant to the mixed solution to perform a coprecipitation reaction, followed by aging; and then calcining the product obtained by aging.

[0010] The transition metal salt is selected from one of Group VIB metal salts, Group VIII metal salts, Group IB metal salts and Group IIB metal salts.

[0011] The third aspect of the present invention provides a composite catalyst prepared according to the method described in the second aspect.

[0012] A fourth aspect of the present invention provides a method for producing olefins by dehydrating alcohol, comprising: contacting alcohol with the catalyst of the first or second aspect in the presence or absence of a carrier gas to carry out a dehydration reaction.

[0013] Through the above technical solution, the present invention introduces alkaline earth metal oxides and transition metal oxides into the ZrO2-based catalyst, which can increase the alkalinity of the ZrO2-based catalyst while forming unbalanced charge sites on the surface of the composite oxide, thereby forming new catalyst surface acid centers, which is beneficial to improving the catalytic performance of the composite catalyst and increasing the selectivity of α-olefins in the alcohol dehydration reaction. DETAILED DESCRIPTION

[0014] The endpoints of the ranges and any values disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0015] As mentioned above, the first aspect of the present invention provides a composite catalyst, which comprises a main component of ZrO2, an alkaline earth metal oxide, and a transition metal oxide; wherein, in the composite catalyst, the pore volume with a pore diameter in the range of 1.7-2.6 nm accounts for more than 60% of the total pore volume of the composite catalyst;

[0016] Relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.05-8 parts by weight; the transition metal oxide is 0.08-10 parts by weight;

[0017] Wherein, the transition metal oxide is selected from one of Group VIB, VIII, IB, and IIB metal oxides.

[0018] According to the present invention, under preferred conditions, the alkaline earth metal oxide is selected from at least one of magnesium oxide, calcium oxide, strontium oxide and barium oxide; more preferably, magnesium oxide and / or calcium oxide.

[0019] According to the present invention, under preferred conditions, the transition metal oxide is selected from one of chromium oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide and zinc oxide; preferably nickel oxide or copper oxide.

[0020] In the present invention, in order to further optimize the selectivity of the composite catalyst for α-olefins, under preferred conditions, relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.1-5 parts by weight, more preferably 0.5-1.4 parts by weight, for example, it can be 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, or any value in the range consisting of any two of the above values.

[0021] In the present invention, in order to further optimize the selectivity of the composite catalyst for α-olefins, under preferred conditions, relative to 100 parts by weight of the main component ZrO2, the transition metal oxide is 0.1-4.5 parts by weight, preferably 0.25-1.1 parts by weight, for example, it can be 0.25 part by weight, 0.3 part by weight, 0.35 part by weight, 0.4 part by weight, 0.45 part by weight, 0.5 part by weight, 0.55 part by weight, 0.6 part by weight, 0.65 part by weight, 0.7 part by weight, 0.75 part by weight, 0.8 part by weight, 0.85 part by weight, 0.9 part by weight, 0.95 part by weight, 1.0 part by weight, 1.05 parts by weight, 1.1 parts by weight, or any value in the range composed of any two of the above numerical values.

[0022] According to the present invention, further preferably, the weight ratio of the alkaline earth metal oxide to the transition metal oxide is 0.1-62.5:1, preferably 0.75-14:1.

[0023] In the present invention, under the preferred conditions, the carbon dioxide adsorption capacity of the composite catalyst is 0.17-0.3 mmol·g -1 The amount of the medium-strong basic center of the composite catalyst is 0.09-0.24mmol·g -1 Under the above preferred conditions, the selectivity of the composite catalyst to α-olefins in the alcohol dehydration reaction can be further improved.

[0024] In the present invention, in order to further improve the catalytic performance of the composite catalyst, under preferred conditions, the specific surface area of the composite catalyst is 50-130m 2 ·g -1 ; Further preferably, in the composite catalyst, the pore volume with a pore diameter in the range of 1.7-2.6 nm accounts for 65-90% of the total pore volume of the composite catalyst, preferably 65-70%; the pore volume with a pore diameter less than 1.7 nm accounts for 0-6% of the total pore volume of the composite catalyst, preferably 2-4%.

[0025] The present invention does not particularly limit the composition of the main component and the alkaline earth metal oxide and transition metal oxide. The alkaline earth metal oxide and rare earth metal oxide may be supported on the main component or dispersed within the main component. In the present invention, they are preferably dispersed within the main component, i.e., the catalyst is a composite metal oxide catalyst. In the present invention, the dispersion or support of the alkaline earth metal oxide and transition metal oxide has little effect on the microstructure of the catalyst. Therefore, the resulting catalyst has a pore structure similar to that of the main component.

[0026] In the present invention, the catalyst can be prepared by using an existing method in which the pore size content meets the above range.

[0027] The second aspect of the present invention provides a method for preparing the catalyst, comprising: mixing a zirconium source, an alkaline earth metal salt, and a transition metal salt in a solvent at a molar ratio of 1:0.0003-0.2:0.0001-0.02 to obtain a mixed solution; then adding a precipitant to the mixed solution to perform a coprecipitation reaction, and then aging the mixed solution; and then calcining the product obtained by aging.

[0028] The transition metal salt is selected from one of Group VIB metal salts, Group VIII metal salts, Group IB metal salts and Group IIB metal salts.

[0029] In the above catalyst preparation method, those skilled in the art will understand that: if the zirconium source provided already contains the required amount of alkaline earth metal elements and transition metal elements, then only this raw material (zirconium source) needs to be used for molding; if the raw material providing the main component source does not contain alkaline earth metal elements and transition metal elements or the content of the elements is low (insufficient), then additional alkaline earth metal elements and transition metal elements can be introduced.

[0030] In the present invention, since the alkaline earth metal salt and the transition metal salt are introduced during the preparation of the main component (ZrO2), the alkaline earth metal oxide and the transition metal oxide are mainly dispersed in the main component.

[0031] According to the present invention, under preferred conditions, the zirconium source is selected from at least one of zirconium oxychloride, zirconium nitrate, zirconyl nitrate and zirconyl sulfate.

[0032] According to the present invention, under preferred conditions, the precipitant is selected from at least one of ammonia water, urea, sodium carbonate and sodium hydroxide.

[0033] In the present invention, the alkaline earth metal salt is present in the form of a solution of an alkaline earth metal salt (hereinafter referred to as solution A), and the alkaline earth metal salt is selected from at least one of alkaline earth metal nitrates, alkaline earth metal formates, alkaline earth metal oxalates and alkaline earth metal lactates; preferably, alkaline earth metal nitrates; further preferably, the alkaline earth metal nitrate is selected from at least one of magnesium nitrate, calcium nitrate, strontium nitrate and barium nitrate, preferably magnesium nitrate and / or calcium nitrate; the solvent in the solution is selected from water and / or ethanol, preferably water.

[0034] In the present invention, the transition metal salt is present in the form of a solution of a transition metal salt (hereinafter referred to as solution B), and the transition metal salt is selected from at least one of transition metal nitrates, transition metal formates, transition metal oxalates and transition metal lactates; preferably, a transition metal nitrate; further preferably, the transition metal nitrate is selected from one of chromium nitrate, iron nitrate, cobalt nitrate, nickel nitrate, copper nitrate and zinc nitrate, preferably nickel nitrate or copper nitrate; the solvent in the solution is selected from water and / or ethanol, preferably water.

[0035] In the present invention, the solution A and the solution B can be added to the system containing the zirconium source simultaneously or separately. When added separately, there is no particular limitation on the order of adding the solution A and the solution B.

[0036] The present invention can provide an embodiment in which the aging operation can be to place the product of the coprecipitation reaction at a constant temperature. Under preferred conditions, the aging temperature is 60-90°C, preferably 65-85°C, for example, it can be 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, or any value in the range of any two of the above values; more preferably, the aging time is 0.5-9h, for example, it can be 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, or any value in the range of any two of the above values.

[0037] According to the present invention, under preferred conditions, the method further comprises: centrifuging, washing and drying the product obtained by aging. The drying time can be reasonably selected according to the drying temperature, the amount of material and the type of drying equipment, so that the water content of the dried material does not affect the subsequent roasting. Under preferred conditions, the drying temperature is 65-140°C, for example, it can be 65, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C or any value in the range of any two of the above values, preferably 80-130°C; the drying time is 4-18h, for example, it can be 4 h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h, 10h, 10.5h, 11h, 11.5h, 12h, 12.5h, 13h, 13.5h, 14h, 14.5h, 15h, 15.5h, 16h, 16.5h, 17h, 17.5h, 18h or any value in the range consisting of any two of the above values.

[0038] According to the present invention, calcination can remove the crystal water in the salt and decompose the salt to generate oxides. In order to optimize the catalytic activity of the catalyst, under preferred conditions, the calcination conditions include: 1-5 ° C min -1 The temperature is raised to 400-800°C at a heating rate of 100-200°C and calcined at 400-800°C for 1-18h; illustratively, the calcination temperature may be 400°C, 450°C, 500°C, 525°C, 550°C, 600°C, 625°C, 650°C, 675°C, 700°C, 750°C, 800°C or any value in the range of any two of the above values, preferably 400-600°C; the calcination time may be 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 7h, 8h, 9h, 9.5h, 10h, 10.5h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h or any value in the range of any two of the above values, preferably 1-6h.

[0039] The third aspect of the present invention provides a composite catalyst prepared according to the method described in the second aspect.

[0040] Under preferred conditions, the composite catalyst comprises main components ZrO2, alkaline earth metal oxide and transition metal oxide; wherein, in the composite catalyst, the pore volume with a pore diameter in the range of 1.7-2.6 nm accounts for more than 60% of the total pore volume of the composite catalyst.

[0041] Preferably, relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.05-8 parts by weight, preferably 0.1-5 parts by weight, more preferably 0.5-1.4 parts by weight;

[0042] The transition metal oxide is 0.08-10 parts by weight, preferably 0.1-4.5 parts by weight, more preferably 0.25-1.1 parts by weight; wherein the transition metal oxide is selected from one of Group VIB, VIII, IB, and IIB metal oxides.

[0043] Preferably, the carbon dioxide adsorption capacity of the composite catalyst is 0.17-0.3 mmol·g -1 The amount of the medium-strong basic center of the composite catalyst is 0.09-0.24mmol·g -1 .

[0044] Preferably, the specific surface area of the composite catalyst is 50-130m 2 ·g -1; Further preferably, in the composite catalyst, the pore volume with a pore diameter in the range of 1.7-2.6 nm accounts for 65-90% of the total pore volume of the composite catalyst, and the pore volume with a pore diameter less than 1.7 nm accounts for 0-6% of the total pore volume of the composite catalyst.

[0045] A fourth aspect of the present invention provides a method for dehydrating alcohol to produce olefins, the method comprising: contacting alcohol with the catalyst of the first aspect or the third aspect in the presence or absence of a carrier gas to carry out a dehydration reaction;

[0046] Preferably, the dehydration reaction conditions include: temperature of 250-380°C, preferably 260-340°C, more preferably 255-330°C; pressure of 0.08-0.3 MPa; liquid phase volume space velocity of 0.05-0.8h -1 , preferably 0.15-0.55h -1 .

[0047] According to the present invention, under preferred conditions, when a carrier gas is present, the flow rate of the carrier gas is 15-45 mL min -1 , preferably 20-40 mL min -1 .

[0048] According to the present invention, under preferred conditions, the alcohol is selected from C3-C 18 alcohol; further preferably, preferably, the alcohol is selected from 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-heptadecanol, 1-octadecanol, 2-propanol, 2-butanol, 2-pentanol, 2-hexanol, 2-heptanol, 2-octanol, 2-nonanol, 2-decanol, 2-undecanol, 2-dodecanol, At least one of 2-tridecyl alcohol, 2-tetradecanol, 2-hexadecanol, 2-heptadecanol, 2-octadecanol, methyl isobutyl carbinol, diacetone alcohol, phenylethyl alcohol, 1-phenyl-2-propanol, 4-phenyl-2-butanol, 5-phenyl-2-pentanol, phenylpropyl alcohol, 4-phenylbutanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 2-methyl-2-hexanol, 2-methyl-2-heptanol, 2-methyl-2-octanol, 2-methyl-2-nonanol, and 5-methyl-2-hexanol.

[0049] In the present invention, room temperature refers to a temperature of 25±5°C.

[0050] In the following examples, the elemental composition of the catalysts was analyzed by plasma emission spectrometry;

[0051] The specific surface area and pore volume of the catalyst were measured by nitrogen adsorption-desorption method (BET). The test conditions were as follows: experimental gas: N2 (purity 99.999%); degassing conditions: 10°C min -1 The temperature was raised to 350°C and vacuumed for 4 h. Instrument name: Automatic Micropore & Chemisorption Analyzer; Instrument model: ASAP2420, MICROMERITICS (USA);

[0052] The CO2 adsorption capacity of the catalyst was tested by CO2-TPD, with a desorption temperature of 100-600℃. The test conditions were: accurately weigh about 0.1g of sample and put it into the sample tube, and then purge it with He gas at 10℃min. -1 Raise to 600℃, stay for 1h, then reduce to 120℃, change the gas to 10% CO2-He mixture, adsorb for 60min, then change to He gas purge for 1h, start counting after the baseline is stable, and use 10℃ min -1 The temperature was raised to 600°C and maintained for 30 minutes. The recording was stopped, and the experiment was completed. The peak area was integrated to calculate the CO2 desorption amount (the basicity of the catalyst). The instrument used was an Automated Catalyst Characterization System (Autochem 2920, manufactured by MICROMERITICS, USA).

[0053] The amount of medium-strong basic centers of the catalyst is tested by CO2-TPD with a desorption temperature of 230-600°C. The specific test method is the same as the basic site test method.

[0054] The carbon deposits on the catalyst were measured using an O2-TPO test. The test conditions were as follows: 0.2 g of sample was accurately weighed, and argon was used as the carrier gas at a flow rate of 40 mL / min. The sample was pretreated at 150°C for 60 minutes, then cooled to 100°C. A mixture of oxygen and argon (20% oxygen by volume) was used as the analytical gas at a flow rate of 40 mL / min. The sample was then subjected to a temperature-programmed oxidation process at a rate of 10°C / min to 900°C. The CO2 and CO gas signals were detected during the temperature-programmed oxidation process. The test instrument was a fully automatic temperature-programmed chemical adsorption instrument (AutoChem II 2920, manufactured by Micromeritics, USA).

[0055] Example 1

[0056] Dissolve 1.59 mol zirconium oxynitrate, 0.045 mol calcium nitrate tetrahydrate, and 0.0009 mol chromium nitrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 , Ca 2+ The concentration is 0.015 mol L -1 Cr 3+ The concentration is 0.0003 mol L -1 a mixed solution; in a water bath at 82°C with vigorous stirring, an aqueous ammonia solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 10.2 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.5 h; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 75°C for 2 h and then at 130°C for 2 h; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 400°C and calcined at this temperature for 2h to obtain a sample ZrO2 / CaO / Cr2O3, which was recorded as catalyst A-1. The test results are shown in Table 1.

[0057] Example 2

[0058] Dissolve 1.59 mol zirconium oxynitrate, 0.036 mol calcium nitrate tetrahydrate, and 0.0042 mol ferric nitrate nonahydrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 , Ca 2+ The concentration is 0.012 mol L -1 、Fe 3+ The concentration is 0.014 mol L -1 a mixed solution; in an 85°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.9 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.6 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 85°C for 2 hours and then at 115°C for 2 hours; finally, the dried product was precipitated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 600°C and calcined at this temperature for 2h to obtain a sample of ZrO2 / CaO / Fe2O3, which was designated as catalyst A-2. The test results are shown in Table 1.

[0059] Example 3

[0060] Dissolve 1.62 mol zirconium oxynitrate, 0.177 mol calcium nitrate tetrahydrate, and 0.018 mol cobalt nitrate hexahydrate in 3 L of deionized water to prepare a zirconium concentration of 0.54 mol L -1 , Ca2+ The concentration is 0.059 mol L -1 、Co 2+ The concentration is 0.006 mol / L -1 a mixed solution; in a 60°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 10.2 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.4 h; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 76°C for 2 h and then at 130°C for 2 h; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 700°C and calcined at this temperature for 2h to obtain a sample ZrO2 / CaO / CoO, which was designated as catalyst A-3.

[0061] Example 4

[0062] Dissolve 1.59 mol zirconium oxynitrate, 0.039 mol calcium nitrate tetrahydrate, and 0.003 mol nickel nitrate hexahydrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 , Ca 2+ The concentration is 0.013 mol L -1 、Ni 2+ The concentration is 0.0011 mol L -1 a mixed solution; in a 78°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.8 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.7 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 74°C for 2 hours and then at 128°C for 2 hours; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 550°C and calcined at this temperature for 2 h to obtain a sample of ZrO2 / CaO / NiO, which was designated as catalyst A-4.

[0063] Example 5

[0064] Dissolve 1.62 mol zirconium oxynitrate, 0.018 mol calcium nitrate tetrahydrate, and 0.009 mol copper nitrate trihydrate in 3 L of deionized water to prepare a zirconium concentration of 0.54 mol L -1 , Ca 2+ The concentration is 0.006 mol L -1 、Cu 2+ The concentration is 0.003 mol / L -1a mixed solution; in a 75°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 10.0 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.6 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 82°C for 2 hours and then at 124°C for 2 hours; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 500°C and calcined at this temperature for 2h to obtain a sample ZrO2 / CaO / CuO, which was designated as catalyst A-5.

[0065] Example 6

[0066] Dissolve 1.59 mol zirconium oxynitrate, 0.048 mol calcium nitrate hexahydrate, and 0.0024 mol zinc nitrate hexahydrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 , Ca 2+ The concentration is 0.016 mol L -1 、Zn 2+ The concentration is 0.0008 mol L -1 a mixed solution; in an 80°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.9 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.9 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 71°C for 2 hours and then at 129°C for 2 hours; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 600°C and calcined at this temperature for 2h to obtain a sample ZrO2 / CaO / ZnO, which was designated as catalyst A-6.

[0067] Example 7

[0068] Dissolve 1.59 mol zirconium oxynitrate, 0.063 mol magnesium nitrate, and 0.027 mol copper nitrate trihydrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 Mg 2+ The concentration is 0.021 mol L -1 、Cu 2+ The concentration is 0.009 mol L -1a mixed solution; in a 78°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 10.1 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.4 h; then centrifuged, and the obtained precipitate was washed with deionized water to pH = 6.5, followed by drying at 65°C for 2 h and then at 130°C for 2 h; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 500°C and calcined at this temperature for 2h to obtain a sample ZrO2 / MgO / CuO, which was recorded as catalyst A-7.

[0069] Example 8

[0070] Dissolve 1.62 mol zirconium oxynitrate, 0.0006 mol barium nitrate, and 0.246 mol copper nitrate trihydrate in 3 L of deionized water to prepare a zirconium concentration of 0.54 mol L -1 、Ba 2+ The concentration is 0.0002 mol L -1 、Cu 2+ The concentration is 0.082 mol L -1 a mixed solution; in a water bath at 83°C with vigorous stirring, an aqueous ammonia solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 10.2 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.6 h; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 75°C for 2 h and then at 125°C for 2 h; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The heating rate was increased from 25°C to 800°C and calcined at this temperature for 2h to obtain a sample ZrO2 / BaO / CuO, which was designated as catalyst A-8.

[0071] Example 9

[0072] Dissolve 1.59 mol zirconium oxynitrate, 0.153 mol strontium nitrate, and 0.0012 mol copper nitrate trihydrate in 3 L of deionized water to prepare a zirconium concentration of 0.53 mol L -1 、Sr 2+ The concentration is 0.051 mol L -1 、Cu 2+ The concentration is 0.0004 mol L -1a mixed solution; in a 75°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.8 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.4 h; then centrifuged, and the obtained precipitate was washed with deionized water to pH = 6.5, followed by drying at 80°C for 2 h and then at 120°C for 2 h; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 550°C and calcined at this temperature for 2 h to obtain a sample of ZrO2 / SrO / CuO, which was designated as catalyst A-9.

[0073] Comparative Example 1

[0074] The catalyst was prepared according to the method of Example 5, except that zirconium oxide powder was used as the main component source, as shown in Table 1, and the calcination temperature during the preparation of the catalyst was 550°C, to obtain a sample ZrO2 (powder) / CaO / CuO, and obtain catalyst B-1.

[0075] Comparative Example 2

[0076] The catalyst was prepared according to the method of Example 5, except that zirconium oxide powder was used as the main component source, as shown in Table 1, and the calcination temperature during the preparation of the catalyst was 900°C, to obtain a sample ZrO2 (powder) / CaO / CuO, and obtain catalyst B-2.

[0077] Comparative Example 3

[0078] Weigh 1.59 mol of zirconium oxynitrate and dissolve it in 3 L of deionized water to prepare a zirconium element concentration of 0.53 mol L -1 Then, in a 70°C water bath with vigorous stirring, an aqueous ammonia solution (25 wt%) was added dropwise to the solution to adjust the pH of the solution to 10.0 to obtain a mixed system, and then the mixed system was allowed to stand in a beaker for 2.5 hours; then, the mixture was centrifuged and the obtained precipitate was washed with deionized water to a pH of 6.5, and then dried at 70°C for 2 hours and then at 130°C for 2 hours; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 500°C and calcined at this temperature for 2 h to obtain a ZrO2 sample, which was designated as catalyst B-3. The test results are shown in Table 1.

[0079] Comparative Example 4

[0080] Weigh 1.62 mol zirconium oxynitrate and 0.036 mol calcium nitrate tetrahydrate and dissolve them in 3 L deionized water to prepare a zirconium concentration of 0.53 mol L -1 , Ca 2+ The concentration is 0.012 mol L-1 a mixed solution; in a 90°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.9 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.6 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 65°C for 2 hours and then at 140°C for 2 hours; finally, the dried product was precipitated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 450°C and calcined at this temperature for 2 h to obtain a sample ZrO2 / CaO, which was designated as catalyst B-4. The test results are shown in Table 1.

[0081] Comparative Example 5

[0082] Weigh 1.60 mol zirconium oxynitrate and 0.0009 mol chromium nitrate and dissolve them in 3 L deionized water to prepare a zirconium concentration of 0.53 mol L -1 Cr 3+ The concentration is 0.0003 mol L -1 a mixed solution; in an 80°C water bath with vigorous stirring, an ammonia aqueous solution (25 wt%) was added dropwise to the mixed solution to adjust the pH to 9.8 to obtain a precipitate system; the precipitate system was allowed to stand in a beaker for 2.6 hours; then centrifuged, and the obtained precipitate was washed with deionized water to a pH of 6.5, followed by drying at 75°C for 2 hours and then at 130°C for 2 hours; finally, the dried product was refrigerated in a muffle furnace at 3°C min -1 The temperature was raised from 25°C to 500°C and calcined at this temperature for 2 h to obtain a sample ZrO2 / Cr2O3, which was designated as catalyst B-5. The test results are shown in Table 1.

[0083] Comparative Example 6

[0084] The catalyst was prepared according to the method of Example 5, except that 0.00072 mol of calcium nitrate tetrahydrate was weighed and dissolved in 3 L of deionized water, as shown in Table 1, to obtain a sample ZrO2 / CaO / CuO, which was recorded as catalyst B-6.

[0085] Comparative Example 7

[0086] The catalyst was prepared according to the method of Example 5, except that 0.54 mol of calcium nitrate tetrahydrate was weighed and dissolved in 3 L of deionized water, as shown in Table 1, to obtain a sample ZrO2 / CaO / CuO, which was recorded as catalyst B-7.

[0087] Comparative Example 8

[0088] The catalyst was prepared according to the method of Example 5, except that 0.0011 mol of copper nitrate trihydrate was weighed and dissolved in 3 L of deionized water, as shown in Table 1, to obtain a sample ZrO2 / CaO / CuO, which was recorded as catalyst B-8.

[0089] Comparative Example 9

[0090] The catalyst was prepared according to the method of Example 5, except that 0.4 mol of copper nitrate trihydrate was weighed and dissolved in 3 L of deionized water, as shown in Table 1, to obtain a sample ZrO2 / CaO / CuO, which was recorded as catalyst B-9.

[0091] Comparative Example 10

[0092] The catalyst was prepared according to the method of Example 5, except that the calcination temperature during the preparation of the catalyst was 250°C. As shown in Table 1, a sample ZrO2 / CaO / CuO (250°C) was obtained, which was recorded as catalyst B-10.

[0093] Comparative Example 11

[0094] The catalyst was prepared according to the method of Example 5, except that the calcination temperature during the preparation of the catalyst was 1000°C. As shown in Table 1, a sample ZrO2 / CaO / CuO (1000°C) was obtained, which was recorded as catalyst B-11.

[0095] Table 1

[0096]

[0097]

[0098] Note: 1-IIA refers to the weight of alkaline earth metal oxide relative to 100g of the main component ZrO2;

[0099] 2-Transition refers to the weight of transition metal oxide relative to 100g of the main component ZrO2;

[0100] 3-1.7-2.6nm is the percentage of pore volume with pore diameter in the range of 1.7-2.6nm to the total pore volume of the composite catalyst;

[0101] 4-<1.7nm The percentage of pore volume with pore diameter less than 1.7nm in the total pore volume of the composite catalyst.

[0102] Test Example 1

[0103] This test example is used to illustrate the method for preparing 4-methyl-1-pentene by dehydrating methyl isobutyl carbinol (MIBC).

[0104] 50 mL of catalyst was weighed and loaded into a fixed bed reactor. Before the reaction, it was preheated at 310 ° C for 1 h in a nitrogen atmosphere. Methyl isobutyl carbinol was metered at 0.3 h. -1 The liquid phase volume space velocity enters the reaction system, the dehydration reaction temperature is 320℃, the reaction pressure is 0.1MPa, and after the reaction stabilizes (that is, when the reaction time is 200h), the reaction liquid is sampled and analyzed. The analysis results are listed in Table 2.

[0105] The sampling and analysis method is gas chromatography, which is calibrated by preparing correction factors of standard samples;

[0106] The conversion rate and selectivity were calculated based on the molar content of each component in the reaction solution (methyl isobutyl carbinol is abbreviated as MIBC, 4-methyl-1-pentene is abbreviated as 4MP1, 4-methyl-2-pentene is abbreviated as 4MP2, and methyl isobutyl ketone is abbreviated as MIBK).

[0107] MIBC conversion rate = 100% - n1 / [(n1+n2+n3+n4)+2×n5]×100%

[0108] 4MP1 selectivity = n2 / [(n2+n3+n4)+2×n5]×100%

[0109] 4MP2 selectivity = n3 / [(n2+n3+n4)+2×n5]×100%

[0110] Wherein, n1 is the molar content of MIBC in the reaction solution; n2 is the molar content of 4MP1 in the reaction solution; n3 is the molar content of 4MP2 in the reaction solution; n4 is the molar content of MIBK in the reaction solution; and n5 is the molar content of oligomers in the reaction solution.

[0111] 4MP1 ratio = 4MP1 / (4MP2+4MP1)×100%

[0112] The 4MP1 ratio is the ratio of 4MP1 selectivity to the sum of 4MP1 and 4MP2 selectivities, that is, the ratio of α-olefin to the sum of α-olefin and β-olefin, indicating that the product generated by the reaction contains more α-olefin, that is, the selectivity of α-olefin is high.

[0113] Table 2

[0114]

[0115] As can be seen from the data in Table 2, in the reaction of dehydrating methyl isobutyl carbinol (MIBC) to prepare 4-methyl-1-pentene, the conversion rate of methyl isobutyl carbinol of the composite catalyst provided by the present invention is as high as 95%, and the proportion of 4MP1 is as high as 91%, indicating that the composite catalyst provided by the present invention has higher activity.

[0116] When the catalytic reaction was continued for 1200 h, the conversion rate and selectivity of the composite catalysts A-1 to A-9 did not change significantly compared with those at 200 h. The conversion rate of MIBC decreased by no more than 1.3%, and the reduction in the proportion of 4MP1 was no more than 1%. However, the conversion rate and the proportion of 4MP1 of the composite catalysts B-1 to B-11 were significantly reduced after 1200 h of the catalytic reaction compared with those at 200 h. The conversion rate decreased by 22-34%, and the proportion of 4MP1 decreased by 19%-38%. Moreover, the carbon deposit amounts of the composite catalysts A-1 to A-9 after 1200 h of the catalytic reaction were all less than 2 wt%. The carbon deposit amounts of the catalysts B-1 to B-11 reached 3.9-8.6 wt%, which indicates that the catalysts prepared in the embodiments of the present invention have a longer service life.

[0117] Test Example 2

[0118] This test example is used to illustrate the method for preparing 1-hexene by dehydrating 2-hexanol.

[0119] 50 mL of catalyst A-5 was placed in a fixed bed reactor and preheated at 310 °C for 1 h in a nitrogen atmosphere before the reaction. 2-hexanol was added via a metering pump at a rate of 0.3 h -1 The liquid phase volume space velocity enters the reaction system, the dehydration reaction temperature is 310℃, the reaction pressure is 0.1MPa, and after the reaction stabilizes, the reaction liquid is sampled and analyzed. The analysis results are shown in Table 3:

[0120] The sampling and analysis method is gas chromatography, which is calibrated by preparing correction factors of standard samples;

[0121] The conversion rate and selectivity were calculated based on the molar content of each component in the reaction solution.

[0122] 2-Hexanol conversion = 100% - m1 / [(m1+m2+m3)+2×m4]×100%

[0123] 1-Hexene selectivity = m2 / [(m2+m3)+2×m4]×100%

[0124] 2-Hexene selectivity = m3 / [(m2+m3)+2×m4]×100%

[0125] Wherein, m1 is the molar content of 2-hexanol in the reaction solution; m2 is the molar content of 1-hexene in the reaction solution; m3 is the molar content of 2-hexene in the reaction solution; and m4 is the molar content of oligomers in the reaction solution.

[0126] 1-hexene ratio = 1-hexene / (2-hexene + 1-hexene) × 100%

[0127] The 1-hexene ratio is the ratio of 1-hexene selectivity to the sum of 1-hexene and 2-hexene selectivities, that is, the ratio of α-olefins to the sum of α-olefins and β-olefins, indicating that the product generated by the reaction has more α-olefins, that is, the selectivity of α-olefins is high.

[0128] Table 3

[0129]

[0130]

[0131] As can be seen from Table 3, in the reaction of catalyzing the dehydration of 2-hexanol to produce 1-hexene by catalyst A-5, the conversion rate of 2-hexanol is as high as 92.52%, and the proportion of 1-hexene is as high as 90.3%. After 1200 hours of catalytic reaction, the conversion rate of 2-hexanol and the proportion of 1-hexene do not change significantly compared with those at 200 hours. The decrease in conversion rate is no more than 0.1%, and the decrease in 1-hexene proportion is no more than 0.1%, indicating that the catalyst obtained in this embodiment of the present invention has a long service life.

[0132] Test Example 3

[0133] This test example is used to illustrate the method for preparing 1-butene by dehydrating 2-butanol in the present invention.

[0134] 50 mL of catalyst A-5 was placed in a fixed bed reactor and preheated at 310 °C for 1 h in a nitrogen atmosphere before the reaction. 2-Butanol was added via a metering pump at a rate of 0.3 h. -1 The liquid phase volume space velocity enters the reaction system, the dehydration reaction temperature is 310 ° C, the reaction pressure is 0.1 MPa, and after the reaction stabilizes, the reaction liquid is sampled and analyzed. The analysis results are shown in Table 4:

[0135] The sampling and analysis method is gas chromatography, which is calibrated by preparing correction factors of standard samples;

[0136] The conversion rate and selectivity were calculated based on the molar content of each component in the reaction solution.

[0137] 2-Butanol conversion rate = 100% - w1 / [(w1+w2+w3)+2×w4]×100%

[0138] 1-Butene selectivity = w2 / [(w2+w3)+2×w4]×100%

[0139] 2-Butene selectivity = w3 / [(w2+w3)+2×w4]×100%

[0140] Wherein, w1 is the molar content of 2-butanol in the reaction solution; w2 is the molar content of 1-butene in the reaction solution; w3 is the molar content of 2-butene in the reaction solution; and w4 is the molar content of oligomers in the reaction solution.

[0141] 1-Butene ratio = 1-Butene / (2-Butene+1-Butene)×100%

[0142] The 1-butene ratio is the ratio of 1-butene selectivity to the sum of 1-butene and 2-butene selectivities, that is, the ratio of α-olefins to the sum of α-olefins and β-olefins, indicating that the product generated by the reaction contains more α-olefins, that is, the selectivity of α-olefins is high.

[0143] Table 4

[0144]

[0145] As can be seen from Table 3, in the reaction of catalyzing the dehydration of 2-butanol to prepare 1-butene by catalyst A-5, the conversion rate of 2-hexanol is as high as 91.08%, and the proportion of 1-butene is as high as 88.6%. After 1200 hours of catalytic reaction, the conversion rate of 2-hexanol and the proportion of 1-butene do not change significantly compared with 200 hours, and the reduction in conversion rate is no more than 0.1%, and the reduction in 1-butene proportion is no more than 0.1%, indicating that the catalyst obtained in this embodiment of the present invention has a long service life.

[0146] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A composite catalyst, characterized in that The composite catalyst comprises a main component of ZrO2, an alkaline earth metal oxide, and a transition metal oxide; wherein, in the composite catalyst, the pore volume with a pore diameter in the range of 1.7-2.6 nm accounts for 65-90% of the total pore volume of the composite catalyst; the pore volume with a pore diameter less than 1.7 nm accounts for 0-6% of the total pore volume of the composite catalyst; The specific surface area of the composite catalyst is 50-130m 2 ·g -1 ; Relative to 100 parts by weight of the main component ZrO2, the alkaline earth metal oxide is 0.1-5 parts by weight, and the transition metal oxide is 0.1-4.5 parts by weight; Wherein, the transition metal oxide is selected from one of Group VIB, VIII, IB, and IIB metal oxides; The amount of medium-strong basic center of the composite catalyst is 0.13-0.24 mmol·g -1 .

2. The composite catalyst according to claim 1, wherein The alkaline earth metal oxide is selected from at least one of magnesium oxide, calcium oxide, strontium oxide and barium oxide.

3. The composite catalyst according to claim 2, wherein The alkaline earth metal oxide is magnesium oxide and / or calcium oxide.

4. The composite catalyst according to any one of claims 1 to 3, wherein The transition metal oxide is selected from one of chromium oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide and zinc oxide.

5. The composite catalyst according to claim 4, wherein The transition metal oxide is nickel oxide or copper oxide.

6. The composite catalyst according to any one of claims 1 to 3 and 5, wherein The weight ratio of the alkaline earth metal oxide to the transition metal oxide is 0.1-62.5:

1.

7. The composite catalyst according to claim 6, wherein The weight ratio of the alkaline earth metal oxide to the transition metal oxide is 0.75-14:

1.

8. The composite catalyst according to any one of claims 1 to 3, 5 and 7, wherein The carbon dioxide adsorption capacity of the composite catalyst is 0.17-0.3 mmol·g -1 .

9. A method for preparing the composite catalyst according to any one of claims 1 to 8, characterized in that: The method comprises: mixing a zirconium source, an alkaline earth metal salt and a transition metal salt in a solvent at a molar ratio of 1:0.0003-0.2:0.0001-0.02 to obtain a mixed solution; then adding a precipitant to the mixed solution to perform a coprecipitation reaction, and then performing aging; and then calcining the product obtained by the aging; The transition metal salt is selected from one of Group VIB metal salts, Group VIII metal salts, Group IB metal salts and Group IIB metal salts.

10. The method according to claim 9, wherein: The zirconium source is selected from at least one of zirconium oxychloride, zirconium nitrate, zirconyl nitrate and zirconyl sulfate; The precipitant is selected from at least one of ammonia water, urea, sodium carbonate and sodium hydroxide.

11. The method according to claim 9 or 10, wherein: The alkaline earth metal salt exists in the form of an alkaline earth metal salt solution, and the alkaline earth metal salt is selected from at least one of alkaline earth metal nitrates, alkaline earth metal formates, alkaline earth metal oxalates and alkaline earth metal lactates.

12. The method according to claim 11, wherein The alkaline earth metal salt is selected from at least one of magnesium nitrate, calcium nitrate, strontium nitrate and barium nitrate.

13. The method according to claim 12, wherein: The alkaline earth metal salt is magnesium nitrate and / or calcium nitrate.

14. The method according to claim 9, wherein The transition metal salt is selected from at least one of transition metal nitrates, transition metal formates, transition metal oxalates and transition metal lactates.

15. The method according to claim 14, wherein The transition metal salt is selected from one of chromium nitrate, iron nitrate, cobalt nitrate, nickel nitrate, copper nitrate and zinc nitrate.

16. The method according to claim 15, wherein The transition metal salt is nickel nitrate and / or copper nitrate.

17. The method according to claim 9, wherein The aging conditions include: temperature of 60-90° C. and time of 0.5-9 h.

18. The method according to claim 9, wherein The calcination conditions include: 1-5℃‧min -1 The heating rate is from room temperature to 400-800°C, and calcined at 400-800°C for 1-18h.

19. The composite catalyst prepared by the method according to any one of claims 9 to 18.

20. A method for preparing olefins by dehydrating alcohols, characterized in that: The method comprises: contacting alcohol with the catalyst according to any one of claims 1 to 8 and 19 in the presence or absence of a carrier gas to carry out a dehydration reaction.

21. The method according to claim 20, wherein The dehydration reaction conditions include: temperature of 250-380°C; pressure of 0.08-0.3 MPa; liquid phase volume space velocity of 0.05-0.8 h -1 .

22. The method according to claim 21, wherein The dehydration reaction conditions include: temperature of 260-340°C; liquid phase volume space velocity of 0.15-0.55 h -1 .

23. The method according to any one of claims 20 to 22, wherein: When carrier gas is present, the flow rate of the carrier gas is 15-45 mL‧min -1 .

24. The method according to claim 23, wherein The flow rate of the carrier gas is 20-40 mL‧min -1 .

25. The method according to claim 20, wherein The alcohol is selected from C3-C 18 of alcohol.

26. The method according to claim 25, wherein The alcohol is selected from 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-heptadecanol, 1-octadecanol, 2-propanol, 2-butanol, 2-pentanol, 2-hexanol, 2-heptanol, 2-octanol, 2-nonanol, 2-decanol, 2-undecanol, 2-dodecanol, 2-tridecanol, At least one of 2-tetradecanol, 2-hexadecanol, 2-heptadecanol, 2-octadecanol, methyl isobutyl carbinol, diacetone alcohol, phenylethyl alcohol, 1-phenyl-2-propanol, 4-phenyl-2-butanol, 5-phenyl-2-pentanol, phenylpropyl alcohol, 4-phenylbutanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 2-methyl-2-hexanol, 2-methyl-2-heptanol, 2-methyl-2-octanol, 2-methyl-2-nonanol, and 5-methyl-2-hexanol.

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