CN115304078A - Preparation method and application of molecular sieve - Google Patents

Preparation method and application of molecular sieve Download PDF

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CN115304078A
CN115304078A CN202210992397.1A CN202210992397A CN115304078A CN 115304078 A CN115304078 A CN 115304078A CN 202210992397 A CN202210992397 A CN 202210992397A CN 115304078 A CN115304078 A CN 115304078A
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molecular sieve
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aluminum
gallium
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姚元根
吴思琪
覃业燕
郭榕
陈建珊
吴翰英
刘洋
刁稚芳
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Fujian Institute of Research on the Structure of Matter of CAS
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    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B39/00—Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination
    • C01B39/02—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof; Direct preparation thereof; Preparation thereof starting from a reaction mixture containing a crystalline zeolite of another type, or from preformed reactants; After-treatment thereof
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    • B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
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Abstract

The application discloses a preparation method and application of a molecular sieve, which comprises the following steps: a) Adding a silicon source into a mixed solution containing an aluminum source, a doped different element source and an alkaline substance dropwise, stirring, standing and aging to obtain a gel-like substance; b) Crystallizing the gel substance in a closed container, filtering, and drying to obtain a NaMY-M type molecular sieve; the doped heteroelement source is selected from a gallium source or a boron source; wherein, in the NaMY type molecular sieve, M is doped different elements of a doped different element source. The method adopts a template-free and guide-free method to synthesize the Y-type molecular sieve with the framework doped with the different elements in one step through hydrothermal synthesis, and is simple, green and environment-friendly, the synthesis time is shortened, the influence factors on the synthesis route are reduced, and the synthesis efficiency is improved. The molecular sieve is used as a catalyst carrier in the indirect and dimethyl carbonate synthesis of methanol gas-phase oxidation carbonylation, so that the conversion rate of carbon monoxide and the yield of dimethyl carbonate in the reaction are improved.

Description

Preparation method and application of molecular sieve
Technical Field
The application relates to a preparation method and application of a molecular sieve, belonging to the technical field of catalysis.
Background
Dimethyl carbonate (DMC) is an environment-friendly and green organic compound, has wide application and good application prospect in the chemical field, and has extremely active chemical properties because DMC molecules have various groups such as methoxy, carbonyl methyl and the like. DMC has lower toxicity, and can be used as carbonylation and methylation reagent to replace poisonous phosgene and dimethyl sulfate. DMC also has a high oxygen content and a rapid biodegradability, which makes it an extremely promising oil additive. Furthermore, DMC can also be used as an electrolyte for lithium ion batteries, which is also a common monomer for the production of polycarbonates. Therefore, the DMC has wide market prospect. Among the many synthesis methods, the methanol gas phase oxidation carbonylation indirect method is considered as one of the most promising process routes by the researchers due to the mild process conditions, low cost and high atom efficiency.
The palladium-based catalyst is a catalyst commonly used in a methanol gas phase oxidation carbonylation indirect method reaction, and can be divided into a chlorine-containing system and a chlorine-free system according to whether the catalyst contains chlorine, the catalyst of the chlorine-containing system has high activity and selectivity in the initial reaction stage, but the reaction activity is reduced due to the loss of chloride ions along with the lapse of time, so that hydrogen chloride gas needs to be supplemented into the system to maintain the stability of the reaction, and the loss of the chloride ions causes corrosion to reaction equipment, thereby increasing the production cost. In recent years, the chlorine-free system has better stability, and the chlorine-free system thoroughly avoids the problem of equipment corrosion, so that the research and study of chlorine-free system catalysts by researchers are attracted, but the reaction activity of the chlorine-free system catalysts is far different from that of a chlorine system, and therefore, for the reaction, the improvement of the activity and the selectivity of the chlorine-free system catalysts is of great importance.
The catalyst carrier of the chlorine-free system is mainly a Y molecular sieve system, the Y molecular sieve is a solid acid material with a twelve-membered ring three-dimensional pore structure and consists of a hexagonal prism cage, a sodalite cage and an ultra cage, and the unique pore structure and the ion exchange characteristic of the Y molecular sieve have important application in the fields of gas separation and catalysis, so that the Y molecular sieve is synthesized by a hydrothermal synthesis method in industry at present. In the process of hydrothermal synthesis, the silicon-aluminum gel is depolymerized under the action of certain temperature, pressure and mineralizer to generate 'nutrient substance' required by the growth of the molecular sieve. After reacting for a certain time, molecular sieve crystals are generated, and the generated molecular sieve is related to the composition of the silicon-aluminum gel and the reaction conditions.
In order to improve the activity and selectivity of the chlorine-free molecular sieve based catalyst, researchers have conducted a great deal of research on the chlorine-free molecular sieve based catalyst in the last decades, and the Japanese UBE company firstly applied the NaY molecular sieve as the carrier in the methanol gas phase oxidation carbonylation indirect method reaction in 1997, the NaY supported catalyst has good stability but low activity, and the DMC has a space-time yield of only 200 g/(L) ("L") cat-1 H). The NaY molecular sieve is doped with potassium in a liquid ion exchange form and is used as a carrier to prepare the catalyst, the NaY molecular sieve is applied to the reaction, the catalytic performance is improved by utilizing the synergistic effect of the potassium and the palladium, and although the catalytic performance is improved to a certain extent, the space-time yield is still low and is 696 g/(L) cat-1 H). At present, the application of the Y molecular sieve is mostly limited to commercial molecular sieves, the process of autonomously synthesizing the framework doped molecular sieve is complicated, a template agent and a guiding agent method are often adopted, the template agent can cause certain pollution to the environment, and the concept of green synthesis is contrary to the concept of environment-friendly synthesis; the synthesis steps of the guide agent method are complicated, the factors influencing the synthesis are quite many, and the carrier acidity is regulated and controlled to be applied to the methanol gas by doping different elements in the frameworkStrategies in phase oxidation carbonylation indirect processes have not been reported.
In conclusion, the development of a Y-type molecular sieve synthetic route with an in-situ framework doped with different elements, a simple synthetic method and adjustable acidity has very important significance and value when the Y-type molecular sieve is used as a carrier to be applied to the methanol gas phase oxidation carbonylation indirect method reaction.
Disclosure of Invention
In order to solve the defects and shortcomings of the existing synthesis route of the in-situ framework doped Y-type molecular sieve, the synthesis route provided by the invention adopts a template-free and guide-agent-free method to synthesize the Y-type molecular sieve with the framework doped with different elements in one step, and the method is simple, green and environment-friendly, shortens the synthesis time, reduces the influence factors on the synthesis route, improves the synthesis efficiency, and is used as a carrier to be applied to a catalyst for methanol gas phase oxidation carbonylation indirect reaction.
According to one aspect of the present application, there is provided a method of preparing a molecular sieve, comprising the steps of:
a) Adding a silicon source into a mixed solution containing an aluminum source, a doped different element source and an alkaline substance dropwise, stirring, standing and aging to obtain a gel-like substance;
b) Crystallizing the gel-like substance in a closed container, filtering, and drying to obtain a NaMY type molecular sieve;
the doped metal source is selected from a gallium source or a boron source;
wherein, in the NaMY type molecular sieve, M is a different element doped with a different element source.
Optionally, the aluminum source is selected from at least one of sodium aluminate, aluminum nitrate, aluminum sulfate.
Optionally, the silicon source is selected from at least one of kaolin, silica sol, sodium silicate, tetraethyl orthosilicate.
Optionally, the gallium source is selected from at least one of gallium nitrate, gallium sulfate, gallium hydroxide.
Optionally, the boron source is selected from sodium metaborate.
Optionally, the alkaline substance is selected from at least one of sodium hydroxide and ammonia water.
Optionally, in the gel-like substance (Al) 2 O 3 +Ga 2 O 3 /B 2 O 3 )：Na 2 O：SiO 2 ：H 2 The molar ratio of O is 1: (10-14): (8-16): (300-600), wherein the mol numbers of the aluminum source, the doped different element source, the alkaline substance and the silicon source are respectively calculated by the mol number of the oxide of the metal element, and the (Al) is 2 O 3 +Ga 2 O 3 /B 2 O 3 ) Expressed as Al 2 O 3 And Ga 2 O 3 Total number of moles of (A) or Al 2 O 3 And B 2 O 3 Total moles of (a).
Optionally, the molar ratio of the aluminum source to the doped dissimilar element source is 1: (0.25-5) based on the molar amount of the aluminum element and the doping foreign element.
Alternatively, the molar ratio of the aluminum source to the doping heteroelement source is selected from any ratio or a range of values between 1.25, 1.
Optionally, the molar ratio of the aluminum source to the doped dissimilar element source is 1: (0.25-3).
Optionally, the stirring time is 30-180 min.
Optionally, the stirring time is selected from any value of 30min, 60min, 90min, 120min, 180min or a range value between the two values.
Optionally, the stirring time is 60-120 min.
Optionally, the temperature of the standing and aging is 20-65 ℃, and the time of the standing and aging is 8-48 h.
Optionally, the temperature of the standing aging is selected from any value of 20 ℃, 30 ℃, 45 ℃, 50 ℃, 65 ℃ or a range value between the two values.
Optionally, the standing and aging time is selected from any value of 8h, 15h, 24h, 28h and 48h or a range value between the two values.
Optionally, the standing and aging time is 12-28 h.
Optionally, the crystallization temperature is 80-120 ℃, and the crystallization time is 8-48 h.
Optionally, the crystallization temperature is selected from any value or a range between two values of 80 ℃, 90 ℃, 100 ℃, 110 ℃ and 120 ℃.
Optionally, the crystallization time is selected from any value or a range between any two values of 8h, 12h, 24h, 30h and 48h.
Optionally, the crystallization time is 12 to 30 hours.
Optionally, the drying temperature is 80-120 ℃, and the drying time is 6-18 h.
Optionally, the drying temperature is selected from any value or a range value between 80 ℃, 90 ℃, 100 ℃, 110 ℃ and 120 ℃.
Optionally, the drying time is selected from any value or a range value between 6h, 8h, 12h, 16h and 18h.
According to the application, the application of the molecular sieve obtained based on the preparation method in the indirect synthesis of dimethyl carbonate through gas-phase oxidative carbonylation is provided.
The specific application mode of the molecular sieve is as follows: the catalyst is used as a carrier in a catalyst for indirectly synthesizing dimethyl carbonate through gas-phase oxidation carbonylation;
the catalyst comprises a molecular sieve, an active component and an auxiliary component, wherein the active component and the auxiliary component are loaded on the molecular sieve;
the active component is active metal element palladium, and the auxiliary agent component is auxiliary agent metal element copper.
Optionally, the active component accounts for 0.5-5 wt% of the mass percentage of the catalyst.
Optionally, the active component accounts for any value or a range between two values of 0.5wt%, 1wt%, 3wt%, 4wt% and 5wt% of the mass percentage of the catalyst.
Optionally, the active component accounts for 0.5-3% of the mass of the catalyst.
Optionally, the auxiliary agent component accounts for 0.5-5 wt% of the mass of the catalyst.
Optionally, the auxiliary component accounts for any value or a range between two values of 0.5wt%, 1wt%, 3wt%, 4wt% and 5wt% of the mass percentage of the catalyst.
Optionally, the auxiliary agent component accounts for 0.5-3% of the mass of the catalyst.
As a specific implementation method, the preparation process of the catalyst applied to the indirect synthesis of dimethyl carbonate by methanol gas phase oxidation carbonylation comprises the following steps:
A. dissolving an aluminum source, a gallium source or a boron source in deionized water, adding an alkaline substance into the deionized water, slowly dropwise adding a silicon source into the solution under the stirring condition after the alkaline substance is completely dissolved, then continuously stirring for 30-180min, preferably 60-120min, standing and aging for 8-48h, preferably 12-28h, the aging temperature is 20-65 ℃, preferably 30-40 ℃, forming gel, transferring the gel into a hydrothermal kettle, and crystallizing for 8-48h, preferably 12-30h, wherein the crystallization temperature is 80-120 ℃.
In the gel, na is replaced by Na 2 Expressed in the form of O, al element is Al 2 O 3 Expressed in terms of the form of (1), the Si element is SiO 2 In the form of (1), the Ga and B elements are Ga 2 O 3 And B 2 O 3 Expressed in terms of the form of (Al) in the gel 2 O 3 +Ga 2 O 3 /B 2 O 3 )、Na 2 O、SiO 2 、H 2 Molar ratio of O1-14.
Wherein the aluminum source can be one or more of sodium aluminate, aluminum nitrate and aluminum sulfate; the silicon source can be one or more of kaolin, silica sol, sodium silicate and tetraethyl orthosilicate; the gallium source can be one or more of gallium nitrate, gallium sulfate and gallium hydroxide; the boron source may be sodium metaborate; the alkaline substance can be one or more of sodium hydroxide and ammonia water.
B. And (3) carrying out suction filtration, washing and drying on the crystallized substance for 6-15h, preferably 8-12h, and drying to obtain the NaMY-x type molecular sieve (x is the molar ratio of the doped elements to aluminum; and M is other doped elements: B and Ga).
C. Carrying out active component loading on the obtained NaMY-x molecular sieve, and preparing the catalyst applied to the methanol gas-phase oxidation carbonylation reaction by adopting an ion exchange ammonia distillation method, wherein the preparation method comprises the following steps:
c-1: soaking the NaMY-x molecular sieve in a sodium hydroxide solution for 12-48 h, and drying for later use;
c-2: adjusting the pH value of the mixed solution containing palladium salt and copper salt to 8-13 by using ammonia water and dilute hydrochloric acid;
c-3: adding the molecular sieve prepared by C-1 into the mixed solution prepared by C-2 at the temperature of 30 ℃, and magnetically stirring for 3-5 hours at the rotating speed of 200-500 r/min to ensure that metal cations in the mixed solution are fully exchanged with cations in the carrier;
c-4: and (3) evaporating ammonia in the solution subjected to ion exchange in the C-3 at a constant temperature of 70-90 ℃ until the pH value is neutral, performing suction filtration and water washing, and drying at 100-110 ℃ for 5-7 h to obtain the palladium-based catalyst. The chemical formula of the palladium-based catalyst is PdCuNaMY-x (M is other doped elements, B and Ga, and x is the molar ratio of the doped elements to aluminum), wherein Pd is an active metal, cu is an auxiliary agent, and NaMY-x is a carrier; wherein Pd accounts for 0.5-5 wt% of the mass of the catalyst, and preferably 0.5-3%; cu accounts for 0.5-5 wt% of the mass percentage of the catalyst, and is preferably 0.5-3%. The catalyst using the invention as the carrier not only improves the conversion rate of carbon monoxide, but also obviously improves the space-time yield.
The beneficial effects that this application can produce include:
1) According to the preparation method provided by the application, the Y-type molecular sieve with the framework doped with the different elements is synthesized by a one-step method by adopting a template-free and guide-agent-free method, the method is simple, green and environment-friendly, the synthesis time is shortened, and the influence factors on the synthesis route are reduced.
2) The Y-type molecular sieve provided by the application is applied to a catalyst for indirectly synthesizing dimethyl carbonate through methanol gas-phase oxidation carbonylation, and the acidity of a carrier is adjusted by introducing the difference between electronegativity of a doping element and aluminum into the Y-type molecular sieve, so that Pd is more easily in an oxidation state, the activation of CO is promoted, the CO conversion rate and the yield of dimethyl carbonate in the reaction are improved, and the reaction gas is not easily reduced to form zero-valent palladium so as to inactivate and reduce the activity.
Drawings
FIG. 1 is an XRD spectrum of the molecular sieves of examples 1-4 of the present application and comparative example 1;
FIG. 2 is an XRD spectrum of the molecular sieves of examples 5 to 8 of the present application and comparative example 1;
FIG. 3 is an infrared spectrum of a framework doped gallium and boron molecular sieve and a comparative molecular sieve of the present application.
Detailed Description
The present application will be described in detail with reference to examples, but the present application is not limited to these examples.
The raw materials in the examples of the present application were purchased commercially, unless otherwise specified.
The analysis method in the examples of the present application is as follows:
obtaining an XRD spectrogram of the molecular sieve by using a Rigaku MiniFlexII type X-ray powder diffractometer;
the infrared spectrum of the molecular sieve was obtained using Bruker Vertex70 FT-IR.
The CO conversion and the space-time yield of dimethyl carbonate in the examples of the present application were calculated as follows:
Figure BDA0003804312050000061
Figure BDA0003804312050000062
in the examples of the present application, the CO conversion and the dimethyl carbonate space-time yield were calculated on the basis of carbon moles.
Example 1
Weighing 13.61g of sodium hydroxide, 1.40g of sodium metaaluminate and 2.18g of gallium nitrate, dissolving into 76.53g of deionized water, after completely dissolving, dropwise adding 55.54g of silica sol while stirring, after dropwise adding, stirring for 2h, standing and aging at 35 ℃ for 28h, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating at 100 ℃ for 12h, carrying out suction filtration, washing and drying at 120 ℃ for 6h to obtain the molecular sieve NaGaY-0.5 (the theoretical molar ratio of gallium to aluminum in the molecular sieve is 0.5).
Example 2
Weighing 13.78g of sodium hydroxide, 1.05g of sodium metaaluminate and 5.48g of gallium sulfate, dissolving the sodium hydroxide, the sodium metaaluminate and the gallium sulfate into 76.50g of deionized water, adding 51.89g of sodium silicate after the sodium silicate is completely dissolved, stirring the mixture for 2 hours after the sodium silicate and the sodium silicate are uniformly mixed, standing and aging the mixture for 24 hours at 36 ℃, transferring the mixed gelatinous liquid obtained at the moment into a hydrothermal kettle, heating the mixture for 12 hours at 100 ℃, filtering, washing and drying the mixture for 8 hours at 100 ℃ to obtain the molecular sieve NaGaY-1.0 (the theoretical molar ratio of gallium to aluminum in the molecular sieve is 1.0).
Example 3
Weighing 12.15g of ammonia water, 3.51g of aluminum sulfate and 3.93g of gallium nitrate, dissolving into 76.47g of deionized water, dropwise adding 48.85g of tetraethyl orthosilicate while stirring after the ammonia water is completely dissolved, stirring for 2 hours after the dropwise adding is finished, standing and aging for 24 hours at 30 ℃, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating for 12 hours at 100 ℃, carrying out suction filtration, washing and drying for 9 hours at 80 ℃, and obtaining the molecular sieve NaGaY-1.5 (the theoretical molar ratio of gallium to aluminum in the molecular sieve is 1.5).
Example 4
Weighing 13.95g of sodium hydroxide, 1.82g of aluminum nitrate and 2.06g of gallium hydroxide, dissolving the sodium hydroxide, the aluminum nitrate and the gallium hydroxide into 76.45g of deionized water, dropwise adding 55.54g of silica sol while stirring after the sodium hydroxide, stirring for 2h after the dropwise adding is finished, standing and aging for 20h at 36 ℃, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating for 12h at 100 ℃, carrying out suction filtration, washing and drying for 14h at 120 ℃, and obtaining the molecular sieve NaGaY-2.0 (the theoretical molar ratio of gallium to aluminum in the molecular sieve is 2.0).
Example 5
Weighing 11.23g of sodium hydroxide, 1.68g of sodium metaaluminate and 0.56g of sodium metaborate, dissolving the sodium metaaluminate and the sodium metaborate into 76.23g of deionized water, dropwise adding 55.54g of silica sol while stirring after the sodium metaborate is completely dissolved, stirring for 2h after the dropwise adding is finished, standing and aging at 34 ℃ for 15h, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating at 100 ℃ for 12h, carrying out suction filtration, washing and drying at 120 ℃ for 6h to obtain the molecular sieve NaBY-0.25 (the theoretical molar ratio of boron to aluminum in the molecular sieve is 0.25).
Example 6
Weighing 11.23g of sodium hydroxide, 5.84g of aluminum sulfate and 0.87g of sodium metaborate, dissolving the sodium hydroxide, the aluminum sulfate and the sodium metaborate into 76.77g of deionized water, dropwise adding 48.85g of tetraethyl orthosilicate while stirring after the sodium metaborate is completely dissolved, stirring for 2h after the dropwise adding is finished, standing and aging for 12h at 32 ℃, transferring the mixed gel liquid obtained at the moment into a hydrothermal kettle, heating for 12h at 100 ℃, performing suction filtration, washing and drying for 9h at 100 ℃ to obtain the molecular sieve NaBY-0.5 (the theoretical molar ratio of boron to aluminum in the molecular sieve is 0.5).
Example 7
Weighing 11.23g of sodium hydroxide, 3.12g of aluminum nitrate and 1.20g of sodium metaborate, dissolving the sodium hydroxide, the aluminum nitrate and the sodium metaborate into 76.68g of deionized water, dropwise adding 55.54g of silica sol while stirring after the sodium metaborate is completely dissolved, stirring for 2h after the dropwise adding is finished, standing and aging at 30 ℃ for 24h, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating at 100 ℃ for 12h, performing suction filtration, washing and drying at 120 ℃ for 6h to obtain the molecular sieve NaBY-0.75 (the theoretical molar ratio of boron to aluminum in the molecular sieve is 0.75).
Example 8
Weighing 11.23g of sodium hydroxide, 1.04g of sodium metaaluminate and 1.30g of sodium metaborate, dissolving the sodium metaborate into 76.63g of deionized water, dropwise adding 55.54g of silica sol while stirring after the sodium metaborate is completely dissolved, stirring for 2h after the dropwise adding is finished, standing and aging at 30 ℃ for 24h, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating at 100 ℃ for 12h, performing suction filtration, washing and drying at 80 ℃ for 10h to obtain the molecular sieve NaBY-1.0 (the theoretical molar ratio of boron to aluminum in the molecular sieve is 1.0).
Comparative example 1
Weighing 11.60g of ammonia water and 2.09g of sodium metaaluminate, dissolving the ammonia water and the sodium metaaluminate into 76.52g of deionized water, dropwise adding 55.54g of silica sol while stirring after the ammonia water and the sodium metaaluminate are completely dissolved, stirring for 2 hours after the dropwise adding is finished, standing and aging for 24 hours at 30 ℃, transferring the obtained mixed gel liquid into a hydrothermal kettle, heating for 12 hours at 100 ℃, carrying out suction filtration, washing and drying for 7 hours at 100 ℃, and obtaining the molecular sieve NaY.
Comparative example 2
Weighing 13.61g of sodium hydroxide, 2.18g of sodium metaaluminate, 3.98g of gallium nitrate and 55.54g of silica sol, dissolving the sodium hydroxide, the sodium metaaluminate, the gallium nitrate and the silica sol into 76.53g of deionized water, stirring for 2 hours, standing and aging at 35 ℃ for 28 hours, transferring the mixed sol liquid obtained at the moment into a hydrothermal kettle, heating at 100 ℃ for 12 hours, carrying out suction filtration, washing and drying at 120 ℃ for 6 hours to obtain the molecular sieve NaGaY-0.5.
Application example
Ten samples of examples 1 to 8 and comparative examples 1 and 2 are used as carriers, and active metal Pd is loaded by an ion exchange method 2+ Assistant Cu 2+ The catalyst for the methanol gas phase oxidation carbonylation indirect method reaction is prepared by the specific operation that 0.0385g of copper nitrate is dissolved in 10ml of deionized water, 102 microliter of palladium nitrate solution is dripped into the copper nitrate solution after the copper nitrate solution is dissolved, 1ml of 28 percent strong ammonia water is dripped into the palladium nitrate solution after the palladium nitrate solution and the palladium nitrate solution are mixed evenly, and the palladium, the copper and the ammonia mixed solution is obtained after the palladium, the copper and the ammonia mixed solution are continuously stirred for 0.5 h; and weighing 1g of the carrier, placing the carrier in a palladium-copper-ammonia mixed solution, stirring for 6 hours at room temperature, carrying out suction filtration, and drying in an oven at 100 ℃ overnight to obtain a catalyst precursor.
And (3) calcining the catalyst precursor in a muffle furnace at 200 ℃ for 4h to obtain the corresponding catalyst. ICP was used to measure the contents of active palladium and auxiliary copper in the catalyst, and the results are shown in Table 1.
The calcined catalyst was crushed and sieved to obtain 20 mesh catalyst particles for the following activity characterization experiment.
Catalyst activity test experiment: in a gas-solid phase fixed bed reactor, 200mg of the catalyst particles are filled in the middle of a reaction tube, the reaction temperature is 120 ℃, and the space velocity is 3600h -1 Reacting under normal pressure; the raw materials respectively comprise 1.5ml/min of CO; CH (CH) 3 ONO is 5.0ml/min; n is a radical of 2 5.5ml/min; the reactants reacted on the catalyst surface to form a reactant containing dimethyl carbonate, and the evaluation results are shown in table 1.
TABLE 1
Figure BDA0003804312050000091
Figure BDA0003804312050000101
As can be seen from Table 1, the conversion of CO was 57% to 70%, and the space-time yield of dimethyl carbonate was 1065 g.kg to 1500 g.kg -1 cat h -1 . Meanwhile, the molecular sieve doped with the dissimilar metal elements can be used for effectively improving the conversion rate of CO and the space-time yield of dimethyl carbonate.
As can be seen from fig. 1 and fig. 2, in the spectrum, the peaks of the molecular sieve synthesized by the present invention and the standard card are compared, and after the positions of gallium and boron substituting for framework aluminum are introduced, the framework structure of NaY molecular sieve is not destroyed, and the crystal form of NaY molecular sieve is maintained. And the sequence of silica gel addition can be found to play a very important role in the synthesis of the molecular sieve by the aid of the graph shown in figure 1.
As can be seen from the infrared spectrogram of FIG. 3, the shift of the infrared vibration peak proves that gallium and boron are introduced into the molecular sieve framework.
Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.

Claims (10)

1. A preparation method of a molecular sieve is characterized by comprising the following steps:
a) Adding a silicon source into a mixed solution containing an aluminum source, a doped dissimilar element source and an alkaline substance dropwise, stirring, standing and aging to obtain a gel substance;
b) Crystallizing the gel-like substance obtained in the step a) in a closed container, filtering, and drying to obtain a NaMY type molecular sieve;
the doped heteroelement source is selected from a gallium source or a boron source;
wherein, in the NaMY type molecular sieve, M is a different element doped with a different element source.
2. The preparation method according to claim 1, wherein the aluminum source is at least one selected from the group consisting of sodium aluminate, aluminum nitrate and aluminum sulfate;
preferably, the silicon source is selected from at least one of kaolin, silica sol, sodium silicate and tetraethyl orthosilicate.
3. The production method according to claim 1, wherein the gallium source is selected from at least one of gallium nitrate, gallium sulfate, and gallium hydroxide;
preferably, the boron source is selected from sodium metaborate;
preferably, the alkaline substance is selected from at least one of sodium hydroxide and ammonia water.
4. The method according to claim 1, wherein (Al) is contained in the gel-like substance 2 O 3 +Ga 2 O 3 /B 2 O 3 )：Na 2 O：SiO 2 ：H 2 The molar ratio of O is 1: (10-14): (8-16): (300-600), wherein the mol numbers of the aluminum source, the doped different element source, the alkaline substance and the silicon source are respectively calculated by the mol number of the oxide of the metal element.
5. The method of claim 1, wherein the molar ratio of the aluminum source to the doped heteroelement source is 1: (0.25-5) based on the molar amount of the aluminum element and the doped heteroelement;
preferably, the molar ratio of the aluminum element to the doping foreign element source is 1: (0.25-3).
6. The method according to claim 1, wherein the stirring time is 30 to 180min;
preferably, the stirring time is 60 to 120min.
7. The preparation method according to claim 1, wherein the temperature of the standing and aging is 20 to 65 ℃, and the time of the standing and aging is 8 to 48 hours;
preferably, the standing and aging time is 12 to 28 hours.
8. The preparation method according to claim 1, wherein the crystallization temperature is 80-120 ℃, and the crystallization time is 8-48 h;
preferably, the crystallization time is 12 to 30 hours.
9. The preparation method according to claim 1, wherein the drying temperature is 80-120 ℃ and the drying time is 6-18 h.
10. Use of the molecular sieve obtained by the preparation method according to claims 1 to 9 as a catalyst support in the indirect synthesis of dimethyl carbonate by methanol gas phase oxidative carbonylation.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0820561A (en) * 1994-07-05 1996-01-23 Ube Ind Ltd Production of carbonic acid ester
CN103204517A (en) * 2012-01-16 2013-07-17 湖北大学 Method for synthesizing microporous molecular sieve with methylene doped in skeleton without template
CN107934985A (en) * 2017-10-25 2018-04-20 陕西聚洁瀚化工有限公司 The preparation method of high silica alumina ratio boron sodium Y type molecular sieve
CN112939013A (en) * 2021-03-10 2021-06-11 中国石油大学(北京) High-silicon small-grain Y-type molecular sieve and preparation method and application of template-free molecular sieve
CN114684831A (en) * 2020-12-31 2022-07-01 中海油天津化工研究设计院有限公司 High-silica-alumina-ratio Y molecular sieve with high relative crystallinity and preparation method thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0820561A (en) * 1994-07-05 1996-01-23 Ube Ind Ltd Production of carbonic acid ester
CN103204517A (en) * 2012-01-16 2013-07-17 湖北大学 Method for synthesizing microporous molecular sieve with methylene doped in skeleton without template
CN107934985A (en) * 2017-10-25 2018-04-20 陕西聚洁瀚化工有限公司 The preparation method of high silica alumina ratio boron sodium Y type molecular sieve
CN114684831A (en) * 2020-12-31 2022-07-01 中海油天津化工研究设计院有限公司 High-silica-alumina-ratio Y molecular sieve with high relative crystallinity and preparation method thereof
CN112939013A (en) * 2021-03-10 2021-06-11 中国石油大学(北京) High-silicon small-grain Y-type molecular sieve and preparation method and application of template-free molecular sieve

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王瑞婷;孙详?于丽娟;张培青;: "无导向剂法合成高结晶度NaY分子筛", 烟台大学学报(自然科学与工程版), no. 02, pages 126 *

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