Metal composite oxide, method for preparing the same, and use thereof

Abstract

The application provides a metal composite oxide and a preparation method and application thereof, and belongs to the technical field of catalyst preparation.The metal composite oxide provided by the application is composed of CeO2 and gamma-Al2O3; the CeO2 is loaded on the surface of the gamma-Al2O3; the mass ratio of the CeO2 to the gamma-Al2O3 is 1:9-3:7; the specific surface area of the metal composite oxide is greater than or equal to 380 m 2 / g, the pore volume is greater than or equal to 1.4 cm 3 / g, and the pore size is greater than or equal to 14 nm. Through various technical means such as colloid mill, pH value adjustment, gel reaction, aging and calcination, the specific surface area, pore volume and pore size of the metal composite oxide are improved, and the catalytic activity of the metal composite oxide as a catalyst is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of catalyst preparation, and particularly relates to a metal composite oxide and a preparation method and application thereof. BACKGROUND

[0002] Aluminum oxide Al2O3 is a high-hardness inorganic compound, and gamma-Al2O3 is a widely used catalyst carrier, has an acidic surface, and has the characteristics of stable chemical properties and low cost. However, with the rapid development of industrial technology, the specific surface area, pore volume and pore size of the gamma-Al2O3 prepared by the prior art cannot meet the production requirements.

[0003] CeO2 is a rare earth metal oxide, and has a unique 4f electron structure. CeO2 is nontoxic and has a wide application in the field of catalysts.

[0004] A preparation method of CeO2 / γ-Al2O3 multi-level structure composite microspheres is disclosed in Chinese Patent No. CN103433018A. The CeO2 / γ-Al2O3 prepared by the patent is a hollow microsphere constructed by nano-sheets, and the specific surface area, pore volume and pore size of the sample CeO2 / γ-Al2O3 are not characterized in the patent. Song Xiaolan et al. (Song Xiaolan, Wu Xuelan, et al., Research on Synthesis of CeO2 / γ-Al2O3 Composite Nanocrystals by Chemical Coprecipitation Method, Rare Earths, December 2004, Vol. 25, No. 6, pages 10-14) disclose a method for preparing CeO2 / γ-Al2O3 composite nanocrystal powder by chemical coprecipitation method. The specific surface area of the prepared CeO2 / γ-Al2O3 composite nanocrystal powder is only 199.58 m 2 / g. The specific surface area of the CeO2 / γ-Al2O3 products prepared by the above methods is generally less than 300 m 2 / g, the pore volume is not more than 1.1 cm 3 / g, and the pore size is less than 12 nm. The products have the problems of small specific surface area, small pore volume and small pore size. SUMMARY

[0005] In view of the above, the present application aims to provide a metal composite oxide and a preparation method and application thereof. The metal composite oxide provided by the present application has the advantages of large specific surface area, large pore volume and large pore size.

[0006] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0007] A metal composite oxide, which is composed of CeO2 and γ-Al2O3; the CeO2 is loaded on the surface of the γ-Al2O3; and the mass ratio of the CeO2 to the γ-Al2O3 is 1:9-3:7.

[0008] The specific surface area of the metal composite oxide is greater than or equal to 380 m 2 / g, and the pore volume is greater than or equal to 1.4 cm 3 / g, and the pore size is greater than or equal to 14 nm.

[0009] Preferably, the metal composite oxide is obtained by colloid milling, adjusting pH value, gel reaction, aging and calcination of a preparation raw material; the preparation raw material comprises an aluminum salt, an aluminate and a cerium-containing compound.

[0010] The application provides a preparation method of the metal composite oxide, comprising the following steps:

[0011] Mixing an aluminum salt, a cerium-containing compound and water to obtain a mixed solution A;

[0012] Carrying out colloid milling on the mixed solution A and an aluminate solution to obtain a grinding solution A;

[0013] Adjusting the pH value of the grinding solution A to be alkaline, carrying out gel reaction to obtain a gel system A;

[0014] Aging the gel system A to obtain a cerium-containing pseudo-boehmite A;

[0015] Carrying out calcination on the cerium-containing pseudo-boehmite A to obtain a metal composite oxide.

[0016] Preferably, the aluminum salt is one or more of Al2(SO4)3·18H2O, AlCl3·6H2O and Al(NO3)3·9H2O; the aluminate is one or both of NaAlO2 and KAlO2; the cerium-containing compound is one or both of a cerium salt and CeO2, and the cerium salt comprises one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O and (NH4)2Ce(NO3)6.

[0017] Preferably, in the grinding solution A, the molar ratio of the aluminum salt, the aluminate and the cerium-containing compound is 1:2-6:0.01-0.04;

[0018] The rotation speed of the colloid mill is 1000-3000 r / min, the temperature is 20-25 DEG C, and the time is 5-10 min;

[0019] The pH value ranges from 7.92 to 9.68;

[0020] The temperature of the gel reaction is 25-75 DEG C, the time is 1-5 h, and the stirring speed is 100-600 r / min;

[0021] The temperature of the aging is 25-75 DEG C, and the time is 1-5 h;

[0022] The temperature of the gel reaction is lower than the temperature of the aging;

[0023] The temperature of the calcination is 400-600℃, and the calcination time is 2-4h.

[0024] Preferably, the preparation method of the CeO2 comprises the following steps:

[0025] The cerium salt, water and inorganic base are mixed to perform a precipitation reaction to obtain Ce(OH)3;

[0026] The Ce(OH)3 is subjected to first calcination to obtain CeO2.

[0027] The inorganic base comprises one or more of NaOH, KOH and Ca(OH)2; the molar ratio of the cerium salt to OH - in the inorganic base is 1:3-6;

[0028] The temperature of the first calcination is 400-600℃, and the time is 2-4h.

[0029] The application further provides another preparation method of the metal composite oxide, comprising the following steps:

[0030] The aluminum salt solution and the aluminate solution are subjected to colloidal milling to obtain a milling liquid B;

[0031] The pH value of the milling liquid B is adjusted to be alkaline, a gel reaction is performed, and a gel system B is obtained;

[0032] The gel system B is subjected to aging to obtain pseudo-boehmite B;

[0033] The pseudo-boehmite B is subjected to first calcination to obtain γ-Al2O3;

[0034] The γ-Al2O3, the cerium salt and water are mixed by milling, and second calcination is performed to obtain the metal composite oxide.

[0035] Preferably, the aluminum salt is one or more of Al2(SO4)3·18H2O, AlCl3·6H2O and Al(NO3)3·9H2O; the aluminate is one or both of NaAlO2 and KAlO2; and the cerium salt comprises one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O and (NH4)2Ce(NO3)6.

[0036] Preferably, in the milling liquid B, the molar ratio of the aluminum salt to the aluminate is 1:2-6;

[0037] The rotation speed of the colloidal mill is 1000-3000r / min, the temperature is 20-25℃, and the time is 5-10min.

[0038] The pH value range is 7.92-9.68;

[0039] The temperature of the gel reaction is 25-75 DEG C, the time is 1-5h, and the stirring speed is 100-600r / min;

[0040] The temperature of the aging is 25-75 DEG C, and the time is 1-5h;

[0041] The temperature of the gel reaction is lower than that of the aging;

[0042] The temperature of the first calcination is 400-600 DEG C, and the time is 2-4h;

[0043] The ratio of the gamma-Al2O3 to water is 1g:(1.4-1.6)mL; and the molar ratio of the gamma-Al2O3 to cerium salt is 40:1-4;

[0044] The temperature of the second calcination is 400-600 DEG C, and the time is 2-4h.

[0045] The application provides application of the metal composite oxide as the catalyst in catalytic cracking of heavy oil.

[0046] The application provides a metal composite oxide, which is composed of CeO2 and gamma-Al2O3; the CeO2 is loaded on the surface of the gamma-Al2O3; the mass ratio of the CeO2 to the gamma-Al2O3 is 1:9-3:7; the specific surface area of the metal composite oxide is greater than or equal to 380m 2 / g, the pore volume is greater than or equal to 1.4cm 3 / g, and the pore size is greater than or equal to 14nm. The metal composite oxide provided by the application contains the CeO2 and the gamma-Al2O3 with a specific mass ratio, the CeO2 loaded on the surface of the gamma-Al2O3 can change the electronic distribution of the whole metal composite oxide CeO2-gamma-Al2O3 system, the metal composite oxide provided by the application has the advantages of large specific surface area, large pore volume and large pore size, and the catalytic activity of the metal composite oxide as the catalyst is improved.

[0047] The application provides two preparation methods of the metal composite oxide, wherein the first preparation method directly mixes and reacts an aluminum salt, an aluminate and a cerium-containing compound to obtain the metal composite oxide, the mixing degree of the aluminum salt, the aluminate and the cerium-containing compound can be controlled in the preparation method, the prepared catalyst is uniformly mixed, the dispersion degree of an active center CeO2 on the surface of γ-Al2O3 is good, and the prepared metal composite oxide has moderate particle size.

[0048] The application provides the preparation method of the metal composite oxide, adopts an aluminum salt, an aluminate and a cerium-containing compound, and obtains the metal composite oxide through colloid milling, pH value adjustment, gel reaction, aging and calcination.

[0049] The test results of the examples show that the metal composite oxide prepared in the application has typical CeO2 and γ-Al2O3 structures, CeO2 is loaded on the surface of γ-Al2O3, has large pore volume and large pore size, and has loose and layered and hole-shaped structures and a large specific surface area.

[0050] The present invention also provides the application of the aforementioned metal composite oxide as a catalyst in heavy oil catalytic cracking. The metal composite oxide provided by the present invention has the advantages of large specific surface area, large pore volume and large pore size, which effectively avoids pore blockage caused by the deposition of large molecules in heavy oil residue, improves catalyst activity and efficiency, and can be recycled and reused, thus having considerable industrial application value. Attached Figure Description

[0051] Figure 1 The XRD pattern of the metal composite oxide CeO2-γAl2O3 in Example 1;

[0052] Figure 2 The attached diagram shows the nitrogen adsorption and desorption of the metal composite oxide CeO2-γAl2O3 in Example 1.

[0053] Figure 3 This is a pore volume and pore size distribution diagram of the metal composite oxide CeO2-γAl2O3 in Example 1;

[0054] Figure 4 This is a SEM image of the metal composite oxide CeO2-γAl2O3 in Example 1;

[0055] Figure 5 The XRD pattern of the metal composite oxide CeO2-γAl2O3 in Example 2;

[0056] Figure 6 The attached diagram shows the nitrogen adsorption and desorption of the metal composite oxide CeO2-γAl2O3 in Example 2.

[0057] Figure 7 This is a pore volume and pore size distribution diagram of the metal composite oxide CeO2-γAl2O3 in Example 2;

[0058] Figure 8 This is a SEM image of the metal composite oxide CeO2-γAl2O3 in Example 2;

[0059] Figure 9 The XRD pattern of the metal composite oxide CeO2-γAl2O3 in Example 3;

[0060] Figure 10 The attached diagram shows the nitrogen adsorption and desorption of the metal composite oxide CeO2-γAl2O3 in Example 3;

[0061] Figure 11 This is a pore volume and pore size distribution diagram of the metal composite oxide CeO2-γAl2O3 in Example 3;

[0062] Figure 12 This is a SEM image of the metal composite oxide CeO2-γAl2O3 composite catalyst in Example 3;

[0063] Figure 13 XRD pattern of the γ-Al2O3 in Comparative Example 1;

[0064] Figure 14 Nitrogen adsorption-desorption pattern of the γ-Al2O3 in Comparative Example 1;

[0065] Figure 15 Pore volume-pore size distribution pattern of the γ-Al2O3 in Comparative Example 1;

[0066] Figure 16 SEM pattern of the γ-Al2O3 in Comparative Example 1. DETAILED DESCRIPTION

[0067] The present application provides a metal composite oxide, which is composed of CeO2 and γ-Al2O3; the CeO2 is loaded on the surface of the γ-Al2O3; the mass ratio of the CeO2 and γ-Al2O3 is 1:9-3:7;

[0068] The specific surface area of the metal composite oxide is ≥380m 2 / g, the pore volume is ≥1.4cm 3 / g, and the pore size is ≥14nm.

[0069] In the present application, the mass ratio of the CeO2 and γ-Al2O3 is 1:9-3:7, preferably 1:9.

[0070] In the present application, the specific surface area of the metal composite oxide is preferably 380-480m 2 / g, the pore volume is preferably 1.4-1.8cm 3 / g, and the pore size is preferably 14-18nm.

[0071] In the present application, the metal composite oxide is obtained from the preparation raw materials through colloid mill, pH value adjustment, gel reaction, aging and calcination; in the present application, the preparation raw materials of the metal composite oxide preferably include aluminum salt, aluminate and cerium-containing compound. In the present application, the preparation raw materials preferably further include water, more preferably pure water or deionized water.

[0072] In the present application, the usage ratio of the preparation raw materials of the metal composite oxide is preferably described in the preparation method, which will not be repeated here.

[0073] The present application provides a preparation method of the metal composite oxide, which comprises the following steps:

[0074] Mixing aluminum salt, cerium-containing compound and water to obtain a mixed solution A;

[0075] The mixed solution A and the aluminate solution are subjected to colloidal mill to obtain a grinding liquid A;

[0076] The pH value of the grinding liquid A is adjusted to be alkaline, and a gel reaction is performed to obtain a gel system A;

[0077] The gel system A is aged to obtain a cerium-containing pseudoboehmite A;

[0078] The cerium-containing pseudoboehmite A is calcined to obtain a metal composite oxide.

[0079] The present application mixes an aluminum salt, a cerium-containing compound and water to obtain a mixed solution A.

[0080] In the present application, the aluminum salt is one or more of Al2(SO4)3·18H2O, AlCl3·6H2O and Al(NO3)3·9H2O; the aluminate is one or both of NaAlO2 and KAlO2; the cerium-containing compound is one or both of a cerium salt and CeO2, and the cerium salt includes one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O and (NH4)2Ce(NO3)6.

[0081] In the present application, the preparation method of the CeO2 preferably comprises the following steps: mixing a cerium salt, water and an inorganic base to perform a precipitation reaction to obtain Ce(OH)3; and performing first calcination on the Ce(OH)3 to obtain CeO2.

[0082] In the present application, the cerium salt, water and inorganic base are mixed to perform a precipitation reaction to obtain Ce(OH)3. In the present application, the inorganic base preferably includes one or more of NaOH, KOH and Ca(OH)2. In the present application, the molar ratio of the cerium salt to OH - in the inorganic base is preferably 1:3-6. In the present application, the mixing of the cerium salt, water and inorganic base preferably comprises: dissolving the cerium salt in water to obtain a cerium salt solution; dissolving the inorganic base in water to obtain an inorganic base solution; and mixing the cerium salt solution and the inorganic base solution. After the precipitation reaction, the present application preferably further comprises centrifugation, washing and drying.

[0083] After obtaining the Ce(OH)3, the present application performs first calcination on the Ce(OH)3 to obtain CeO2. In the present application, the temperature of the first calcination is preferably 400-600°C, and the time is preferably 2-4h. In the present application, the first calcination is preferably performed in a muffle furnace.

[0084] In the present application, in the mixed solution A, the concentration of the aluminum salt is preferably 0.2mol / L, and the concentration of the cerium-containing compound is preferably 0.01-0.04mol / L.

[0085] In the present application, the mixing of the aluminum salt, the cerium-containing compound and water preferably comprises: adding the aluminum salt into water, stirring to dissolve, then adding the cerium-containing compound, and stirring to dissolve.

[0086] After obtaining the mixed solution A, the present application subjects the mixed solution A and the aluminate solution to a colloidal mill to obtain a milled solution A.

[0087] In the present application, the concentration of the aluminate solution is preferably 0.4-1.2 mol / L. In the present application, the molar ratio of the aluminum salt, the aluminate and the cerium-containing compound in the milled solution A is preferably 1:2-6:0.01-0.04, and further preferably 1:3-4:0.01-0.02.

[0088] In the present application, the colloidal milling is preferably performed in a colloidal mill device. In the present application, the rotation speed of the colloidal mill is preferably 1000-3000 r / min, and more preferably 2500-3000 r / min, the temperature is preferably 20-25℃, and the time is preferably 5-10 min, and more preferably 5-7 min.

[0089] After obtaining the milled solution A, the present application adjusts the pH value of the milled solution A to be alkaline, performs a gel reaction, and obtains a gel system A.

[0090] In the present application, the pH value range of the milled solution A is preferably 7.92-9.68. In the present application, dilute nitric acid or NaOH solution is preferably used to adjust the pH value of the milled solution A; the concentration of the dilute nitric acid and the NaOH solution is preferably 0.1-0.3 mol / L. In the present application, the temperature of the gel reaction is preferably 25-75℃, and more preferably 25-45℃, the time is preferably 1-5 h, and more preferably 2-3 h, and the stirring speed is preferably 100-600 r / min. In the present application, the stirring is preferably performed using a magnetic stirrer.

[0091] After obtaining the gel system A, the present application subjects the gel system A to aging to obtain a cerium-containing pseudoboehmite A.

[0092] In the present application, the temperature of the aging is preferably 25-75℃, and more preferably 45-55℃, and the time is 1-5 h, and more preferably 2-3 h.

[0093] In the present application, the temperature of the gel reaction is < the temperature of the aging.

[0094] After the aging, the present application preferably further comprises centrifugation, washing, precipitation and drying.

[0095] After obtaining the cerium-containing pseudoboehmite A, the present application subjects the cerium-containing pseudoboehmite A to calcination to obtain a metal composite oxide.

[0096] In the present application, the temperature of the calcination is preferably 400-600℃, more preferably 400-500℃, the calcination time is 2-4h, more preferably 2.5-3.5h, and the temperature rising rate to the temperature of the calcination is preferably 3-8℃ / min. In the present application, the calcination is preferably performed in a muffle furnace.

[0097] After the calcination, the present application preferably further comprises cooling and grinding.

[0098] The present application further provides another preparation method of the metal composite oxide, comprising the following steps:

[0099] The aluminum salt solution and the aluminate solution are subjected to colloidal milling to obtain a grinding liquid B;

[0100] The pH value of the grinding liquid B is adjusted to be alkaline, a gel reaction is performed, and a gel system B is obtained;

[0101] The gel system B is subjected to aging to obtain pseudo-boehmite B;

[0102] The pseudo-boehmite B is subjected to first calcination to obtain γ-Al2O3;

[0103] The γ-Al2O3, cerium salt and water are subjected to grinding mixing, and second calcination is performed to obtain the metal composite oxide.

[0104] In the present application, the aluminum salt solution and the aluminate solution are subjected to colloidal milling to obtain a grinding liquid B.

[0105] In the present application, the aluminum salt is preferably one or more of Al2(SO4)3·18H2O, AlCl3·6H2O and Al(NO3)3·9H2O; and the aluminate is preferably one or both of NaAlO2 and KAlO2.

[0106] In the present application, the concentration of the aluminum salt solution is preferably 0.2mol / L. In the present application, the concentration of the aluminate solution is preferably 0.4-1.2mol / L. In the present application, in the grinding liquid B, the molar ratio of the aluminum salt to the aluminate is preferably 1:2-6.

[0107] In the present application, the colloidal milling is preferably performed in a colloidal milling device. In the present application, the rotation speed of the colloidal milling is preferably 1000-3000r / min, more preferably 2500-3000r / min, the temperature is preferably 20-25℃, and the time is preferably 5-10min, more preferably 5-7min.

[0108] After the grinding liquid B is obtained, the pH value of the grinding liquid B is adjusted to be alkaline, a gel reaction is performed, and a gel system B is obtained.

[0109] In the present application, the pH value of the grinding liquid B is preferably in the range of 7.92-9.68. In the present application, dilute nitric acid or NaOH solution is preferably used to adjust the pH value of the grinding liquid B; the concentration of the dilute nitric acid and the NaOH solution is preferably in the range of 0.1-0.3 mol / L. In the present application, the temperature of the gel reaction is preferably in the range of 25-75℃, more preferably in the range of 25-45℃, the time is preferably in the range of 1-5h, more preferably in the range of 2-3h, and the stirring speed is preferably in the range of 100-600r / min. In the present application, the stirring is preferably performed by using a magnetic stirrer.

[0110] After obtaining the gel system B, the gel system B is aged in the present application to obtain a pseudo-boehmite B.

[0111] In the present application, the temperature of the aging is preferably in the range of 25-75℃, more preferably in the range of 45-55℃, and the time is preferably in the range of 1-5h, more preferably in the range of 2-3h.

[0112] In the present application, the temperature of the gel reaction is lower than the temperature of the aging.

[0113] After the aging, the present application preferably further comprises centrifugation, washing, precipitation and drying.

[0114] After obtaining the pseudo-boehmite B, the pseudo-boehmite B is first calcined in the present application to obtain γ-Al2O3.

[0115] In the present application, the temperature of the first calcination is preferably in the range of 400-600℃, more preferably in the range of 400-500℃, and the calcination time is preferably in the range of 2-4h, more preferably in the range of 2.5-3.5h. In the present application, the first calcination is preferably performed in a muffle furnace.

[0116] After the first calcination, the present application preferably further comprises cooling and grinding.

[0117] After obtaining the γ-Al2O3, the γ-Al2O3, a cerium salt and water are ground and mixed in the present application, and then second calcination is performed to obtain a metal composite oxide.

[0118] In the present application, the cerium salt preferably comprises one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O and (NH4)2Ce(NO3)6.

[0119] In the present application, the ratio of the γ-Al2O3 to water is preferably 1 g : (1.4-1.6) mL; the molar ratio of the γ-Al2O3 to the cerium salt is preferably 40:1-4. In the present application, the grinding mixing of the γ-Al2O3, the cerium salt and water is preferably carried out under stirring, and the stirring time is preferably 4-6 h to make the γ-Al2O3 and the cerium salt uniformly mixed. In the present application, it is preferred to further include drying the uniformly mixed mixture of the γ-Al2O3 and the cerium salt and then carrying out the second calcination, the drying temperature is preferably 55-65℃, and the drying time is preferably 2-4 h.

[0120] In the present application, the temperature of the second calcination is preferably 400-600℃, more preferably 400-500℃, the time is preferably 2-4 h, more preferably 2.5-3.5 h, and the temperature rising rate to the temperature of the second calcination is preferably 3-8℃ / min. In the present application, the second calcination is preferably carried out in a muffle furnace.

[0121] After the second calcination, the present application preferably further includes cooling and grinding.

[0122] The present application further provides the use of the metal composite oxide prepared by the above technical solution or the preparation method as a catalyst in catalytic cracking of heavy oil.

[0123] The technical solution of the present application is further illustrated by specific embodiments, and those skilled in the art should understand that the embodiments are only used to understand the present application and should not be regarded as a specific limitation of the present application.

[0124] Example 1

[0125] 4.9182 g of NaAlO2 was weighed in a beaker, 100 mL of deionized water was added, and it was fully stirred to dissolve, and the concentration was 0.6 mol / L. 7.5026 g of Al(NO3)3.6H2O was weighed in a beaker, 100 mL of deionized water was added, and it was stirred to dissolve, and the concentration was 0.2 mol / L, then 0.4530 g of Ce(NO3)3.6H2O was added, and it was fully stirred to dissolve, and the concentration was 0.01 mol / L. The colloid mill was started, the rotating speed was 3000 r / min, the above prepared NaAlO2 solution and the Al(NO3)3.6H2O solution containing Ce(NO3)3.6H2O were quickly and concurrently added to the colloid mill, and the grinding time was about 5 min, the pH value of the grinding liquid was adjusted to 8.77, it was placed in a magnetic stirrer, the rotating speed was 350 r / min, and the gel reaction was carried out at 25℃ for 2 h, then it was aged at 45℃ for 2 h, centrifuged, the precipitate was washed, and the precipitate was dried in a 60℃ oven. The precipitate was a cerium-containing pseudoboehmite.

[0126] The above Ce-containing pseudo-boehmite is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, the metal composite oxide CeO2-γAl2O3 is obtained after cooling, wherein the mass ratio of CeO2 and γ-Al2O3 is 1:9.

[0127] Example 2

[0128] Ce(NO3)3.6H2O solid 8.6844g is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.1mol / L; 2.4g of NaOH solid is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.3mol / L; the above two solutions are mixed and stirred for about 15min, and then left to settle for 30min, the precipitate is centrifuged and washed, and then placed in a 60°C oven to dry, and the dried precipitate is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, the CeO2 is obtained after cooling.

[0129] NaAlO2 4.9190g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.6mol / L; Al(NO3)3.6H2O 7.4993g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration of the Al(NO3)3.6H2O solution is 0.2mol / L; the colloid mill is started, the speed is 3000r / min, the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution are quickly and continuously added to the colloid mill, and 0.1795g of the above CeO2 powder is added, and the grinding is carried out for about 5min, the pH value of the grinding liquid is adjusted to 8.65, it is placed in a magnetic stirrer, the speed is 350r / min, and the gel reaction is carried out at 25°C for 2h, and after aging at 45°C for 2h, it is centrifuged, the precipitate is washed, and the precipitate is dried in a 60°C oven, and the precipitate is a Ce-containing pseudo-boehmite.

[0130] The above CeO2-containing pseudo-boehmite is placed in a 400°C muffle furnace and calcined for 3h, and after cooling, the metal composite oxide CeO2-γAl2O3 is obtained, wherein the mass ratio of CeO2 and γ-Al2O3 is 1:9.

[0131] Example 3

[0132] Take 4.9195 g NaAlO2 in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration is 0.6 mol / L; respectively take 7.4972 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.80, place it in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0133] Put the above pseudoboehmite in a 400℃ muffle furnace and calcine for 3 h, then cool down to obtain γ-Al2O3.

[0134] Take 4.0784 g of the above γ-Al2O3 in a beaker, add 0.4548 g of Ce(NO3)3.6H2O solid, add 6 mL of deionized water to grind and mix, place it in a magnetic stirrer and stir at 25℃ for 6 h, then dry it in a 60℃ oven, place the dried sample in a muffle furnace, heat it to 400℃ at a rate of 5℃ / min, keep it at 400℃ for 3 h, then cool down to obtain the metal composite oxide CeO2-γAl2O3, wherein the mass ratio of CeO2 to γ-Al2O3 is 1:9.

[0135] Example 4

[0136] Take 4.9224 g NaAlO2 in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration is 0.6 mol / L. Take 7.4855 g Al(NO3)3·6H2O in a beaker, add 100 mL of deionized water, stir to dissolve, the concentration is 0.2 mol / L, then add 1.0214 g Ce(NO3)3.6H2O, stir well to dissolve, the concentration is 0.02 mol / L. Open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution containing Ce(NO3)3.6H2O to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.70, place it in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is cerium-containing pseudoboehmite.

[0137] The above cerium-containing pseudo-boehmite is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, the metal composite oxide CeO2-γAl2O3 is obtained after cooling, wherein the mass ratio of CeO2 and γ-Al2O3 is 2:8.

[0138] Example 5

[0139] Ce(NO3)3.6H2O solid 8.6802g is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.1mol / L; 2.4g of NaOH solid is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.3mol / L; the above two solutions are mixed and stirred for about 15min, and then left to settle for 30min, the precipitate is centrifuged and washed, and then placed in a 60°C oven to dry, and the dried precipitate is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, CeO2 is obtained after cooling.

[0140] NaAlO2 4.9203g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.6mol / L; Al(NO3)3.6H2O 7.4762g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration of the Al(NO3)3.6H2O solution is 0.2mol / L; the colloid mill is started, the speed is 3000r / min, the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution are quickly and concurrently added to the colloid mill, and 0.3518g of the above CeO2 powder is added, and the grinding is carried out for about 5min, the pH value of the grinding liquid is adjusted to 8.76, it is placed in a magnetic stirrer, the speed is 350r / min, and the gel reaction is carried out at 25°C for 2h, and after aging at 45°C for 2h, it is centrifuged, the precipitate is washed, and the precipitate is dried in a 60°C oven, and this precipitate is a cerium-containing pseudo-boehmite.

[0141] The above cerium-containing pseudo-boehmite is placed in a 400°C muffle furnace and calcined for 3h, and after cooling, the metal composite oxide CeO2-γAl2O3 is obtained, wherein the mass ratio of CeO2 and γ-Al2O3 is 2:8.

[0142] Example 6

[0143] Take 4.9215 g NaAlO2 in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration is 0.6 mol / L; respectively take 7.4887 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.78, place in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0144] Put the above pseudoboehmite in a 400℃ muffle furnace and calcine for 3 h, then cool down to obtain γ-Al2O3.

[0145] Take 4.9215 g NaAlO2 in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration is 0.6 mol / L. Take 7.4887 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.78, place in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0146] Example 7

[0147] Take 4.9215 g NaAlO2 in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration is 0.6 mol / L. Take 7.4887 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, fully stir to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.78, place in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0148] The above cerium-containing pseudo-boehmite is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, the metal composite oxide CeO2-γAl2O3 is obtained after cooling, wherein the mass ratio of CeO2 and γ-Al2O3 is 3:7.

[0149] Example 8

[0150] Ce(NO3)3.6H2O solid 8.6818g is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.1mol / L; 2.4g of NaOH solid is weighed into a beaker, 200mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.3mol / L; the above two solutions are mixed and stirred for about 15min, and then left to settle for 30min, the precipitate is centrifuged and washed, and then placed in a 60°C oven to dry, and the dried precipitate is placed in a muffle furnace and calcined at a temperature rising rate of 5°C / min to 400°C, and after 3h of heat preservation, the CeO2 is obtained after cooling.

[0151] NaAlO2 4.9175g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration is 0.6mol / L; Al(NO3)3.6H2O 7.4836g is weighed into a beaker, 100mL of deionized water is added, and it is stirred to dissolve, and the concentration of the Al(NO3)3.6H2O solution is 0.2mol / L; the colloid mill is started, the speed is 3000r / min, the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution are quickly and continuously added to the colloid mill, and 0.7205g of the above CeO2 powder is added, and the grinding is carried out for about 5min, the pH value of the grinding liquid is adjusted to 8.75, it is placed in a magnetic stirrer, the speed is 350r / min, and the gel reaction is carried out at 25°C for 2h, and after aging at 45°C for 2h, it is centrifuged, the precipitate is washed, and the precipitate is dried in a 60°C oven, and this precipitate is a cerium-containing pseudo-boehmite.

[0152] The above cerium-containing pseudo-boehmite is placed in a 400°C muffle furnace and calcined for 3h, and after cooling, the metal composite oxide CeO2-γAl2O3 is obtained, wherein the mass ratio of CeO2 and γ-Al2O3 is 3:7.

[0153] Example 9

[0154] Take 4.9208 g NaAlO2 in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration is 0.6 mol / L; respectively take 7.4933 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.82, place it in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0155] Put the above pseudoboehmite in a 400℃ muffle furnace and calcine for 3 h, then cool down to obtain γ-Al2O3.

[0156] Take 4.9208 g NaAlO2 in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration is 0.6 mol / L; respectively take 7.4933 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.82, place it in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0157] Comparative Example 1

[0158] Take 4.9208 g NaAlO2 in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration is 0.6 mol / L; respectively take 7.4933 g Al(NO3)3.6H2O in a beaker, add 100 mL of deionized water, stir well to dissolve, the concentration of Al(NO3)3.6H2O solution is 0.2 mol / L; open the colloid mill, the speed is 3000 r / min, quickly and flow add the above prepared NaAlO2 solution and Al(NO3)3.6H2O solution to the colloid mill, grind for about 5 min, adjust the pH value of the grinding liquid to 8.82, place it in a magnetic stirrer, the speed is 350 r / min, gelation reaction at 25℃ for 2 h, aging at 45℃ for 2 h, then centrifugal, wash the precipitate, dry the precipitate in a 60℃ oven, the precipitate is pseudoboehmite.

[0159] Put the above pseudoboehmite in a muffle furnace and calcine, the temperature is raised to 400℃ at a rate of 5℃ / min, keep for 3 h, then cool down to obtain γ-Al2O3.

[0160] The prepared sample is subjected to mesopore full analysis by using 4-station specific surface and porosity adsorber (ASAP-2640-4N), and the test items include specific surface area, pore volume and pore size. The specific test results are shown in Table 1.

[0161] Table 1: Test data of the prepared sample of Examples 1-9 and Comparative Example 1

[0162] Serial No. Product Specific surface area (m 2 / g) Pore volume (cm 3 / g) Pore size (nm) Example 1 CeO2-γAl2O3 413.7725 1.6583 16.153 Example 2 CeO2-γAl2O3 446.6745 1.7417 15.597 Example 3 CeO2-γAl2O3 392.5617 1.4391 15.4518 Example 4 CeO2-γAl2O3 410.4382 1.6518 16.0946 Example 5 CeO2-γAl2O3 442.8295 1.7392 15.5733 Example 6 CeO2-γAl2O3 391.7154 1.4325 15.4978 Example 7 CeO2-γAl2O3 411.2539 1.6475 16.0776 Example 8 CeO2-γAl2O3 443.7208 1.7267 15.5649 Example 9 CeO2-γAl2O3 390.6855 1.4278 15.4493 Comparative Example 1 gamma-Al2O3 303.0521 0.6839 9.1663

[0163] The XRD of the sample prepared in the examples and the comparative example is determined by using an X-ray diffractometer, and the test conditions include: working voltage 40 kV, tube current 30 mA, step measurement, starting angle 5°, ending angle 75°, step angle 0.02°, Kα radiation source, Cu target, and the test results are shown in the drawings.

[0164] Figure 1 、 Figure 5 and Figure 9 The XRD of the metal composite oxide CeO2-γAl2O3 prepared in Examples 1-3 is shown in Figures Figure 1 、 Figure 5 and Figure 9 It can be seen from Figures

[0165] Figure 2 、 Figure 6 and Figure 10 The nitrogen adsorption and desorption of the metal composite oxide CeO2-γAl2O3 prepared in Examples 1-3 is shown in Figures Figure 2 、 Figure 6 and Figure 10 The nitrogen adsorption and desorption isotherm in Figures

[0166] Figure 3 、 Figure 7 and Figure 11 The pore volume and pore size distribution of the metal composite oxide CeO2-γAl2O3 prepared in Examples 1-3 is shown in Figures Figure 3 、 Figure 7 and Figure 11 It can be seen from Figures 3The pore volume of greater than or equal to 1 cm3 / g corresponds to a pore diameter of greater than or equal to 14 nm, which indicates that the metal composite oxide prepared in the present application has the characteristics of large pore volume and large pore diameter.

[0167] Figure 4 、 Figure 8 and Figure 12 The SEM image of the metal composite oxide CeO2-γAl2O3 prepared in Examples 1-3 is shown in Figure 1. Figure 4 、 Figure 8 and Figure 12 As can be seen from Figures 1, 2 and 3, the metal composite oxide sample has a layered and hole-like morphology, which indicates that the loading of CeO2 onto γ-Al2O3 not only increases the pore volume and pore diameter of the sample, but also makes the sample present a loose layered and hole-like morphology, thereby increasing the specific surface area of the sample.

[0168] Figure 13 The XRD image of the γ-Al2O3 prepared in Comparative Example 1 is shown in Figure 4. Figure 13 As can be seen from Figure 4, the γ-Al2O3 has characteristic peaks at 2θ = 34.9°, 36.5°, 46.3° and 67°, which is a typical γ-Al2O3 crystal form.

[0169] Figure 14 The nitrogen adsorption / desorption graph of the γ-Al2O3 prepared in Comparative Example 1 is shown in Figure 5. Figure 14 The nitrogen adsorption / desorption isotherm is of type IV in the physical adsorption isotherm types proposed by IUPAC, with a H2 type hysteresis loop, and the adsorption / desorption line occurs in the middle pressure region (P / P0 = 0.45-0.9), with a capillary condensation phenomenon and a clear hysteresis loop, which indicates that there is a mesoporous structure in the sample.

[0170] Figure 15 The pore volume and pore diameter distribution graph of the γ-Al2O3 prepared in Comparative Example 1 is shown in Figure 6. Figure 15 As can be seen from Figure 6, the pore volume of the γ-Al2O3 is less than 1 cm3 / g, which is significantly smaller than the pore volume and pore diameter of the metal composite oxide prepared in Examples 1-3. 3

[0171] Figure 16 The SEM image of the γ-Al2O3 prepared in Comparative Example 1 is shown in Figure 7. Figure 16 As can be seen from Figure 7, the γ-Al2O3 particles are compact and present a block structure, with agglomeration phenomenon.

[0172] By comparing the pore volume and pore diameter distribution graph and the SEM image of the samples prepared in Examples 1-3 and Comparative Example 1, it is clear that the metal composite oxide prepared in Examples 1-3 has CeO2 loaded onto the surface of γ-Al2O3, has large pore volume and large pore diameter, and has a loose layered and hole-like structure with a large specific surface area.

[0173] ​The above merely describes the preferred embodiments of the present application, and does not limit the present application in any form. It should be noted that, for those skilled in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method for preparing a metal composite oxide, characterized in that, Includes the following steps: Aluminum salt, cerium-containing compound and water are mixed to obtain mixture A; The mixture A and the aluminate solution are subjected to colloid milling to obtain grinding fluid A; The pH of the grinding slurry A was adjusted to alkaline, and a gel reaction was carried out to obtain gel system A; The gel system A was aged to obtain cerium-containing pseudoboehmite A; The cerium-containing pseudoboehmite A was calcined to obtain a metal composite oxide; The metal composite oxide is composed of CeO2 and γ-Al2O3; the CeO2 is supported on the surface of the γ-Al2O3; the mass ratio of CeO2 to γ-Al2O3 is 1:9 to 3:

7. The specific surface area of ​​the metal composite oxide is ≥380m². 2 / g, pore volume ≥1.4cm 3 / g, pore size ≥14nm; the morphology of the metal composite oxide is layered and porous; The cerium-containing compound is one or both of cerium salts and CeO2, wherein the cerium salts include one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O, and (NH4)2Ce(NO3)6; The rotation speed of the colloid mill is 1000~3000 r / min, the temperature is 20~25℃, and the time is 5~10 min; The pH value range is 7.92 to 9.

68.

2. The preparation method according to claim 1, characterized in that, The aluminum salt is one or more of Al2(SO4)3∙18H2O, AlCl3∙6H2O, and Al(NO3)3·9H2O; the aluminate is one or two of NaAlO2 and KAlO2.

3. The preparation method according to claim 1 or 2, characterized in that, The gelation reaction was carried out at a temperature of 25-75°C for 1-5 hours, with a stirring speed of 100-600 r / min. The aging temperature is 25~75℃, and the time is 1~5h; The temperature of the gelation reaction is less than the aging temperature; The roasting temperature is 400~600℃, and the roasting time is 2~4h.

4. The preparation method according to claim 1, characterized in that, The method for preparing CeO2 includes the following steps: A cerium salt, water, and inorganic base are mixed and a precipitation reaction is carried out to obtain Ce(OH)3; The Ce(OH)3 was subjected to a first calcination to obtain CeO2; The inorganic base includes one or more of NaOH, KOH, and Ca(OH)₂; the cerium salt reacts with the OH in the inorganic base. - The molar ratio is 1:(3~6); The first roasting temperature is 400~600℃ and the time is 2~4h.

5. A method for preparing a metal composite oxide, characterized in that, Includes the following steps: Aluminum salt solution and aluminate solution are subjected to colloid milling to obtain grinding fluid B; The pH of the grinding slurry B was adjusted to alkaline, and a gelation reaction was carried out to obtain gel system B; The gel system B was aged to obtain boehmite B; The pseudoboehmite B was subjected to a first calcination to obtain γ-Al2O3; The γ-Al2O3, cerium salt and water were ground and mixed, and then subjected to a second calcination to obtain a metal composite oxide. The metal composite oxide is composed of CeO2 and γ-Al2O3; the CeO2 is supported on the surface of the γ-Al2O3; the mass ratio of CeO2 to γ-Al2O3 is 1:9 to 3:

7. The specific surface area of ​​the metal composite oxide is ≥380m². 2 / g, pore volume ≥1.4cm 3 / g, pore size ≥14nm; the morphology of the metal composite oxide is layered and porous; The cerium salt includes one or more of Ce(NO3)3·6H2O, CeCl3·7H2O, Ce2(SO4)3·8H2O, and (NH4)2Ce(NO3)6; In the grinding slurry B, the molar ratio of aluminum salt to aluminate is 1:(2~6). The rotation speed of the colloid mill is 1000~3000 r / min, the temperature is 20~25℃, and the time is 5~10 min; The pH value range is 7.92 to 9.

68.

6. The preparation method according to claim 5, characterized in that, The aluminum salt is one or more of Al2(SO4)3∙18H2O, AlCl3∙6H2O, and Al(NO3)3·9H2O; the aluminate is one or two of NaAlO2 and KAlO2.

7. The preparation method according to claim 5, characterized in that, The gelation reaction was carried out at a temperature of 25-75°C for 1-5 hours, with a stirring speed of 100-600 r / min. The aging temperature is 25~75℃, and the time is 1~5h; The temperature of the gelation reaction is less than the aging temperature; The first roasting temperature is 400~600℃, and the time is 2~4h; The ratio of γ-Al2O3 to water is 1g:(1.4~1.6)mL; The second roasting temperature is 400~600℃, and the time is 2~4h.

8. The application of the metal composite oxide prepared by the preparation method according to any one of claims 1 to 7 as a catalyst in heavy oil catalytic cracking.

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