CN115106122A - Preparation method and application of molecular sieve catalyst - Google Patents

Abstract

The application discloses a preparation method and application of a molecular sieve catalyst, wherein the method comprises the following steps: (1) heating a material containing a mordenite molecular sieve and an organic alkali source to obtain an intermediate product; (2) and roasting the intermediate product to obtain the molecular sieve based catalyst. The catalyst prepared by the invention is used for carbonylation reaction of small molecular compound dimethyl ether, methanol or halogenated methane, and has high activity and stable performance.

Description

A kind of preparation method and application of molecular sieve catalyst

technical field

The present application relates to a preparation method and application of a molecular sieve catalyst, belonging to the field of catalysis.

Background technique

The continuous growth of energy demand and the urgent desire to improve environmental quality make my country's energy development face unprecedented challenges. Based on the requirements of energy security and the characteristics of my country's energy structure of "rich coal, lean oil, and little gas", "efficient conversion and clean utilization of energy" is an inevitable choice for my country's energy development. Small molecule compounds such as methanol, dimethyl ether and halomethane are important platform compounds that can be based on carbon dioxide and natural gas. The directional conversion of small molecular compounds to prepare high value-added compounds such as light olefins, gasoline, aromatic hydrocarbons, paraxylene and oxygenated compounds such as acetic acid, methyl acetate, ethanol, etc. is an effective way to efficiently and cleanly utilize energy.

Directional synthesis of C2 compounds by carbonylation of small molecular compounds (methanol, dimethyl ether and halomethane) and CO - acetic acid and methyl acetate is one of the important research directions of C1 chemical conversion, with extremely important application background and good market prospects . MOR, FER and OFF with eight-membered ring pore structure have catalytic activity for the carbonylation of ethers. Using mordenite as a catalyst, 0.163-MeOAc (g-Cat.h) can be obtained at a reaction pressure of 1 MPa and a temperature of 165 °C. )-1 for the space-time yield. After the introduction of metal Cu and Ag on the MOR catalyst, its carbonylation performance under the reaction conditions (hydrogen atmosphere, 250-300 ℃) is better than that of the unmodified MOR sample. Pre-adsorption of pyridine organic amines is used to improve the properties of mordenite. Due to the size limitation of pyridines, they can only adsorb and poison the acidic sites in the 12-membered ring pores, thereby inhibiting the formation of carbon deposits and improving the carbonylation stability of the catalyst. The activity of the catalyst remained stable within 48 hours of the reaction. The silicon tetrachloride vapor-modified mordenite molecular sieve catalyst can greatly improve the stability of the catalyst in the carbonylation of dimethyl ether by selectively removing the framework aluminum sites in the 12-membered ring pores. An in-situ synthesis method for regulating the placement and distribution of acid centers of mordenite. By regulating the placement of acid centers, a mordenite molecular sieve catalyst with excellent dimethyl ether carbonylation activity was successfully prepared. The above content mainly involves the research of mordenite catalyzed dimethyl ether carbonylation. It is of great application value to carry out researches that are not only suitable for the carbonylation of dimethyl ether, but also for the development of catalysts for the carbonylation of methanol and halomethane.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned problems, the present invention provides a method for preparing a molecular sieve catalyst. The molecular sieve catalyst is obtained by mixing the mordenite molecular sieve with an organic base, heating and calcining the catalyst. The method is simple and convenient, and has strong operability. The regulation of the acid placement of the molecular sieve catalyst can be realized, so that the catalyst has high activity and target product selectivity.

According to one aspect of the present invention, a method for preparing a molecular sieve catalyst is provided, the method comprising: (1) heating a material containing a mordenite molecular sieve and an organic alkali source to obtain an intermediate product; (2) heating the intermediate product; The product is calcined to obtain the molecular sieve catalyst.

Optionally, the organic alkali source is selected from organic amines; the organic amines are selected from at least one of monovalent organic amines, divalent organic amines, and trivalent organic amines.

Optionally, the monovalent organic amine is selected from at least one of the compounds having the chemical formula shown in formula I:

Wherein, R ¹ , R ² and R ³ are independently selected from any one of H and C ₁ -C ₁₀ alkyl groups; R ¹ , R ² and R ³ cannot be H at the same time.

Optionally, in formula I, R ¹ , R ² , and R ³ are independently selected from any one of H and alkyl groups of C ₁ to C ₇ ; R ¹ , R ² , and R ³ cannot be H at the same time.

Optionally, in formula I, R ¹ , R ² , R ³ are independently selected from H, CH ₃ -, CH ₃ CH ₂ -, CH ₃ CH ₂ CH ₂ -, CH ₃ (CH ₂ ) ₂ CH ₂ -, CH ₃ (CH ₂ ) ₃ CH ₂ -, CH ₃ (CH ₂ ) ₄ CH ₂ -, CH ₃ (CH ₂ ) ₅ CH ₂ -, (CH ₃ ) ₂ CH-, (CH ₃ ) ₂ CHCH ₂ - or CH ₃ CH ₂ (CH ₃ )CH-.

Optionally, in formula I, R ¹ , R ² , R ³ are independently selected from H, CH ₃ , CH ₃ CH ₂ -, CH ₃ CH ₂ CH ₂ -, CH ₃ (CH ₂ ) ₂ CH ₂ - one of the.

Optionally, in formula I, R ¹ , R ² , and R ³ are independently selected from one of H, CH ₃ , and CH ₃ CH ₂ —.

Optionally, R ¹ , R ² , R ³ are the same, but different H.

Optionally, R ¹ , R ² , R ³ are not the same.

Preferably, the monobasic organic amine is selected from at least one of triethylamine and n-butylamine.

Preferably, the divalent organic amine is selected from diethylamine.

Optionally, the monovalent organic amine is selected from alkyl ammonium hydroxide; the alkyl ammonium hydroxide is selected from at least one of the compounds having the chemical formula shown in formula II:

Wherein, R ⁴ , R ⁵ , R ⁶ , and R ⁷ are independently selected from any one of C ₁ -C ₁₀ alkyl groups.

Optionally, in formula II, R ⁴ , R ⁵ , R ⁶ , R ⁷ are independently selected from any one of C ₁ -C ₇ alkyl groups.

Alternatively, in formula II, R ⁴ , R ⁵ , R ⁶ , R ⁷ are independently selected from CH ₃ -, CH ₃ CH ₂ -, CH ₃ CH ₂ CH ₂ -, CH ₃ (CH ₂ ) ₂ CH ₂ -, CH ₃ (CH ₂ ) ₃ CH ₂ -, CH ₃ (CH ₂ ) ₄ CH ₂ -, CH ₃ (CH ₂ ) ₅ CH ₂ -, (CH ₃ ) ₂ CH-, (CH ₃ ) ₂ CHCH Any one of _2- , CH ₃ CH ₂ (CH ₃ )CH-.

Alternatively, in formula II, R ⁴ , R ⁵ , R ⁶ , R ⁷ are independently selected from CH ₃ -, CH ₃ CH ₂ -, CH ₃ CH ₂ CH ₂ -CH ₃ (CH ₂ ) ₂ CH ₂ One of -, CH ₃ (CH ₂ ) ₃ CH ₂ -, CH ₃ (CH ₂ ) ₄ CH ₂ -, and CH ₃ (CH ₂ ) ₅ CH ₂ -.

Optionally, R ⁴ , R ⁵ , R ⁶ , R ⁷ are different.

Optionally, R ⁴ , R ⁵ , R ⁶ , R ⁷ are the same.

Preferably, the alkylammonium hydroxide is selected from at least one of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.

Optionally, the preparation method includes: (1) mixing the mordenite molecular sieve and an organic alkali source, and heating under airtight conditions to obtain an intermediate; (2) calcining the intermediate to obtain the molecular sieve catalyst .

Optionally, the heating conditions are as follows: the temperature is 50-220° C. and the time is 5-100 hours.

Optionally, the upper temperature limit of the heating is selected from 60°C, 70°C, 80°C, 90°C, 100°C, 120°C, 140°C, 150°C, 160°C, 170°C, 180°C, 200°C, 210°C or 220°C; the lower limit is selected from 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 120°C, 140°C, 150°C, 160°C, 170°C, 180°C, 200°C or 210°C.

Optionally, the upper limit of the heating time is selected from 6 hours, 12 hours, 18 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 80 hours, 90 hours or 100 hours; the lower limit is selected from 5 hours , 6 hours, 12 hours, 18 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 80 hours, 90 hours, or 99 hours.

Optionally, in step (1), the mordenite molecular sieve and the organic alkali source are mixed, and treated in a closed reactor at a temperature of 50-220° C. for 5-100 hours.

Optionally, the heating conditions are as follows: the temperature is 80-200° C. and the time is 12-72 hours.

Preferably, the heating conditions are as follows: the temperature is 100-200° C. and the time is 18-60 hours.

Optionally, the roasting conditions are as follows: the temperature is 450-650° C., and the time is 1.5-10 hours.

Optionally, the upper limit of the roasting temperature is 480°C, 500°C, 520°C, 550°C, 580°C, 600°C or 650°C; the lower limit is selected from 450°C, 480°C, 500°C, 520°C, 550°C or 600°C.

Optionally, the upper limit of the roasting time is selected from 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours , 8.5 hours, 9 hours, 9.5 hours or 10 hours; the lower limit is selected from 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours hours, 7.5 hours, 8 hours, 8.5 hours, 9 hours or 9.5 hours.

Optionally, the roasting conditions are as follows: the temperature is 450-600° C. and the time is 2-8 hours.

Optionally, the roasting conditions are as follows: the temperature is 450-550° C., and the time is 3-7 hours.

Preferably, the roasting conditions are as follows: the temperature is 500-580° C. and the time is 3-6 hours.

Optionally, the silicon-aluminum atomic ratio of the mordenite molecular sieve is: Si/Al=6-50.

Optionally, the upper limit of the silicon-aluminum atomic ratio of the mordenite molecular sieve is selected from 8, 10, 15, 20, 25, 30, 35, 40, 50; the lower limit is selected from 6, 8, 10, 15, 20, 25 , 30, 35, 40 or 49.

Optionally, the mordenite molecular sieve is selected from at least one of Na-MOR, _NH4 -MOR, and H-MOR molecular sieves.

Optionally, the organic alkali source further includes a solvent; the solvent is selected from water.

Optionally, the mass content of the organic base in the organic base solution is 0.5% to 99.9%.

Optionally, the upper limit of the mass content of the organic base in the organic base solution is selected from 0.8%, 1.0%, 1.5%, 2.0%, 5.0%, 10.0%, 20.0%, 25.0%, 30.0%, 40.0%, 50.0% %, 60.0%, 70.0%, 75.0%, 80.0%, 90.0% or 99.9%; the lower limit is selected from 0.5%, 0.8%, 1.0%, 1.5%, 2.0%, 5.0%, 10.0%, 20.0%, 25.0%, 30.0%, 40.0%, 50.0%, 60.0%, 70.0%, 75.0%, 80.0% or 90.0%.

Optionally, the ratio of the added amount of the mordenite molecular sieve and the organic alkali source is 1 g: 2 ml to 1 g: 20 ml.

Optionally, the upper limit of the ratio of the added amount of the mordenite molecular sieve and the organic alkali source is selected from 1g: 4ml, 1g: 6ml, 1g: 8ml, 1g: 10ml, 1g: 12ml, 1g: 14ml, 1g : 15ml, 1g: 16ml, 1g: 18ml or 1g: 2ml; the lower limit is selected from 1g: 2ml, 1g: 4ml, 1g: 6ml, 1g: 8ml, 1g: 10ml, 1g: 12ml, 1g: 14ml, 1g: 15ml, 1g: 16ml or 1g: 18ml.

According to another aspect of the present application, a molecular sieve catalyst is provided, the molecular sieve catalyst comprising the molecular sieve catalyst obtained according to any one of the above preparation methods.

According to yet another aspect of the present application, a method for preparing acetic acid and methyl acetate is provided. In the presence of a catalyst, compound I is contacted and reacted with a mixed gas containing carbon monoxide to obtain methyl acetate or acetic acid; Catalyst At least one of the molecular sieve catalysts described above and the molecular sieve catalysts prepared according to any of the above methods; the compound I is selected from at least one of methanol, halomethane, and dimethyl ether.

Optionally, the reaction conditions are as follows: the temperature is 150-320° C., the pressure is 0.5-25.0 MPa, and the time is 10-24 h.

Optionally, the upper limit of the pressure of the reaction is selected from 1 MPa, 1.5 MPa, 2 MPa, 3 MPa, 3.5 MPa, 5 MPa, 8 MPa, 10 MPa, 12 MPa, 15 MPa, 18 MPa, 20 MPa, 22 MPa or 25 MPa; 1.5MPa, 2MPa, 3MPa, 3.5MPa, 8MPa, 10MPa, 12MPa, 15MPa, 18MPa, 20MPa or 22MPa.

Optionally, the upper temperature limit of the reaction is selected from 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 250°C, 260°C, 280°C, 300°C or 320°C ; the lower limit is selected from 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 250°C, 260°C, 280°C or 300°C.

Optionally, the upper limit of the reaction time is selected from 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h or 24h; the lower limit is selected from 10h, 11h, 12h, 13h , 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h or 23h.

Optionally, the reaction conditions are as follows: the temperature is 160-320° C., the pressure is 1.0-20.0 MPa, and the time is 10-24 h.

Preferably, the reaction conditions are as follows: the temperature is 170-300° C., the pressure is 1.0-15.0 MPa, and the time is 10-24 h.

Optionally, the feed mass space velocity of the compound I is 0.05˜5 h ⁻¹ .

Optionally, the upper limit of the feed mass space velocity of the compound I is selected from 0.08h ^-1 , 0.1h ^-1 , 0.25h ^-1 , 0.5h ^-1 , 0.8h ^-1 , 1.0h ^-1 , 1.50h ^-1 , 1.75h ^-1 , 2.00h ^-1 , 2.50h ^-1 , 3.00h ^-1 , 3.50h ^-1 , 4.00h ^-1 , 4.50h ^-1 or 5.00h ^-1 ; the lower limit is selected from 0.05h ^-1 , 0.08h ^-1 , 0.1h ^-1 , 0.25h ^-1 , 0.5h ^-1 , 0.8h ^-1 , 1.0h ^-1 , 1.50h ^-1 , 1.75h ^-1 , 2.00h ^-1 , 2.50h ^-1 , 3.00h ^-1 , 3.50h ^-1 , 4.00h ^-1 or 4.50h ^-1 .

Optionally, the feed mass space velocity of the compound I is 0.1˜4.5 h ⁻¹ .

Preferably, the feed mass space velocity of the compound I is 0.1˜4 h ⁻¹ .

Optionally, the molar ratio of the carbon monoxide to the compound I is 0.1:1 to 50:1.

Optionally, the upper limit of the molar ratio of the carbon monoxide to the compound I is selected from 0.2:1, 0.5:1, 1:1, 2:1, 5:1, 6:1, 8:1, 10:1, 15:1, 18:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1 or 50:1; lower limit selected from 0.1:1, 0.2:1, 0.5:1 , 1:1, 2:1, 5:1, 6:1, 8:1, 10:1, 15:1, 18:1, 20:1, 25:1, 30:1, 35:1, 40 :1 or 45:1.

Optionally, the molar ratio of the carbon monoxide to the compound I is 0.5:1 to 50:1.

Optionally, the molar ratio of the carbon monoxide to the compound I is 0.1:1 to 40:1.

Optionally, the molar ratio of the carbon monoxide to the compound I is 0.5:1 to 40:1.

Preferably, the molar ratio of the carbon monoxide to the compound I is 0.5:1 to 25:1.

Optionally, the volume fraction of carbon monoxide in the carbon monoxide-containing gas mixture is 20-100%.

Optionally, the carbon monoxide-containing gas mixture further includes an inert gas. The inert gas is selected from at least one of hydrogen, nitrogen, argon, carbon dioxide, methane, and ethane.

Optionally, the reactor is a fixed bed reactor.

Optionally, when the compound I is selected from dimethyl ether, the selectivity of methyl acetate is greater than 98%.

Optionally, when the compound I is selected from methanol, the selectivity to acetic acid is greater than 85%.

Optionally, when the compound I is selected from halomethanes, the selectivity of methyl acetate+acetic acid is greater than 80%.

The beneficial effects that this application can produce include:

1) the invention provides a kind of catalyst for preparing methyl acetate and or acetic acid, the strong acid content of mordenite molecular sieve and the proportion of strong acid sites in the 8-membered ring channel after the organic base treatment obviously increase, and have higher activity. and target product selectivity.

2) the present invention provides a kind of modification method of molecular sieve, this method is through organic alkali hydrothermal treatment, hydroxide ion can dissolve skeleton atom, and non-skeleton atom can be recrystallized into skeleton atom again under the induction of organic alkali cation, The acid distribution, acid content and acid density of mordenite can be regulated without significantly affecting the crystal morphology, size and pore structure, that is, the regulation of the acid placement of the molecular sieve catalyst can be realized, which provides a new method for the preparation of molecular sieve catalysts. Strategy.

3) The catalyst of the present invention can not only be applied to multiple reactions, including dimethyl ether carbonylation, methanol carbonylation and halomethane carbonylation, but also has a wide adjustable range of reaction process conditions and is universal.

Detailed ways

The present application will be described in detail below with reference to specific embodiments, but the present application is not limited to the following embodiments.

Unless otherwise specified, the raw materials in the examples of this application are all purchased through commercial channels.

The product analysis method in the examples of the present application is as follows: the reacted gas is introduced into an online gas chromatograph through a pipeline for analysis. The gas chromatograph model is Agilent 7890A, equipped with PLOT Q capillary column and TDX-1 packed column, and its outlet is connected to FID detector and TCD detector, respectively.

In the examples of this application, the conversion rate of small molecules and the selectivity of products are calculated as follows:

In the embodiment, the conversion rate of dimethyl ether or methanol or methyl chloride and the selectivity of the product are all calculated based on the number of moles of small molecules:

Conversion rate of dimethyl ether=[(carbon moles of dimethyl ether in raw material gas)-(carbon moles of dimethyl ether in product)]÷(carbon moles of dimethyl ether in raw material gas)×(100%)

Methanol conversion rate=[(Methanol carbon moles in raw material gas)-(Methanol carbon moles in product)]÷(Methanol carbon moles in raw material gas)×(100%)

Conversion rate of methyl chloride = [(the number of moles of methyl chloride in the feed gas) - (the number of moles of methyl chloride in the product)] ÷ (the number of moles of methyl chloride in the feed gas) × (100%)

Methyl acetate selectivity of dimethyl ether carbonylation=(2/3)×(carbon moles of methyl acetate in product)÷[(carbon moles of dimethyl ether in feed gas)−(carbon moles of dimethyl ether in product number)] × (100%)

The acetic acid selectivity of methanol carbonylation=(1/2)×(the number of acetic acid carbon moles in the product)÷[(the number of methanol carbon moles in the feed gas)-(the number of methanol carbon moles in the product)]×(100%)

The acetic acid selectivity of halomethane carbonylation=(1/2)×(the number of moles of acetic acid in the product)÷[(the number of moles of methyl chloride in the feed gas)-(the number of moles of methyl chloride in the product)]×(100 %)

Example 1

Put 10 grams of NH ₄ -MOR (Si/Al=10) molecular sieves into 100 ml of tetraethylammonium hydroxide solution with a mass fraction of 3.0% (solid-to-liquid ratio of 1 g:10 ml), stir until the mixture is uniform, and then transfer Put it into a 150ml high-pressure sealed reactor, treat at 180°C for 48 hours, filter, wash with deionized water, and dry to obtain a solid sample. The prepared sample was calcined at 550°C for 4 hours in an air atmosphere to obtain catalyst 1#.

Example 2

NH ₄ -MOR (Si/Al=10) in Example 1 was replaced with Na-MOR (Si/Al=10) and H-MOR (Si/Al=10), and other conditions were the same as those in Example 1, Catalysts 2# and 3# were prepared in turn

Example 3

The silicon-aluminum atomic molar ratios of NH ₄ -MOR in Example 1 were replaced with 6, 15, 20, and 50, respectively, followed by keeping the same as in Example 1, and catalysts 4#, 5#, 6#, and 7# were prepared in turn. .

Example 4

The tetraethylammonium hydroxide in embodiment 1 is replaced with tetramethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide and other conditions are consistent with embodiment 1, and catalysts 8#, 9#, 10#.

Example 5

The treatment temperature in Example 1 was changed to 50°C, 100°C, 150°C, 170°C, 200°C, and 220°C, and other conditions were kept the same, and catalysts 11#, 12#, 13#, 14#, 15 were obtained in turn. #, 16#.

Example 6

The treatment time in Example 1 was changed to 5 hours, 12 hours, 18 hours, 36 hours, 72 hours, and 100 hours, and other conditions were kept the same, and catalysts 17#, 18#, 19#, 20#, 21 were successively obtained. #,twenty two#.

Example 7

The solid-liquid ratio in Example 1 was changed to 1g:2ml, 1g:8ml, 1g:15ml, 1g:20ml, and other conditions were kept the same, and catalysts 23#, 24#, 25#, and 26# were obtained in sequence.

Example 8

Change the mass concentration of tetraethylammonium hydroxide in Example 1 to 1.5%, 4.5%, 7.5%, 10.5% and 15.0%, and keep other conditions the same, and prepare catalysts 27#, 28#, 29#, 30# in turn , 31#.

Example 9

The tetraethylammonium hydroxide in Example 1 was replaced with ethylenediamine, triethylamine, n-butylamine organic amine, and other conditions were kept the same, and catalysts 32#, 33#, and 34# were obtained in turn.

Example 10

The tetraethylammonium hydroxide in Example 1 was replaced with triethylamine, and the mass percentage content of triethylamine in the aqueous solution was 0.5%, 10%, 25%, 50%, 75%, 100%, and other conditions were the same as Keeping the same in Example 1, catalysts 35#, 36#, 37#, 38#, 39#, and 40# were prepared in sequence.

Example 11

The time of roasting the solid sample obtained in Example 1 in dry air was changed to 1.5 hours, 3 hours, 5 hours, 6 hours, 10 hours, and other conditions were kept the same, and catalysts 41#, 42#, 43#, 44#, 45#.

Example 12

The calcination temperature in Example 1 was changed to 450°C, 500°C, 600°C, and 650°C in turn, and other conditions were kept the same, and catalysts 46#, 47#, 48#, and 49# were obtained in sequence.

Example 13

The above-mentioned catalysts were investigated according to the following conditions for the carbonylation of dimethyl ether to produce methyl acetate.

Load 0.5 g of catalyst into a fixed-bed reactor with an inner diameter of 8 mm, raise it to 400 °C at a rate of 2 °C/min under nitrogen atmosphere, hold for 2 hours, and then lower the temperature to the reaction temperature of 200 °C in the same atmosphere. The pressure of the reaction system was increased to 2 MPa, and the reaction mixture was passed through the catalyst bed from top to bottom. Wherein the dimethyl ether feed space velocity is 1.0h ⁻¹ ; the mol ratio of carbon monoxide and dimethyl ether is 6:1, and the carbon monoxide feed gas contains hydrogen, and the catalytic reaction runs for 10 hours, and the reaction results are shown in Table 1.

Table 1 Catalytic evaluation results of dimethyl ether carbonylation with different catalysts

Example 14

The above-mentioned catalysts were investigated for the performance of methanol carbonylation to produce acetic acid according to the following conditions.

The catalysts used in the experiment are 1#, 5#, 10#, and 15# samples. 1 gram of catalyst was loaded into a fixed bed reactor with an inner diameter of 8 mm, and the temperature was raised to 400 °C at a rate of 2 °C/min under nitrogen atmosphere for 2 hours. , and then the temperature was lowered to the reaction temperature of 280°C in the same atmosphere, the pressure of the reaction system was increased to 2MPa with the reaction mixture, and the reaction mixture passed through the catalyst bed from top to bottom. The methanol feed space velocity was 1.0 h ⁻¹ , the molar ratio of carbon monoxide and methanol was 50:1, the carbon monoxide feed gas contained hydrogen, and the catalytic reaction was run for 10 hours, and the reaction structure was shown in Table 2.

Table 2 Catalytic evaluation results of methanol carbonylation with different catalysts

Example 15

The above-mentioned catalysts were investigated for the production of acetic acid by the carbonylation of halomethanes under the following conditions.

The catalyst used in the experiment was the 5# sample, 1 g of catalyst was loaded into a fixed bed reactor with an inner diameter of 8 mm, and the temperature was raised to 400 °C at a rate of 2 °C/min under nitrogen atmosphere for 2 hours, and then the temperature was lowered to the reaction in the same atmosphere. The temperature was 260°C, and the pressure of the reaction system was increased to 2.5 MPa with the reaction mixture (chloromethane/CO or bromomethane/CO or iodomethane/CO), and the reaction mixture passed through the catalyst bed from top to bottom. Wherein the halomethane feed space velocity is 0.5h ^-1 , the molar ratio of carbon monoxide and halomethane is 20:1, the carbon monoxide feed gas does not contain other gases, the catalytic reaction runs for 20 hours, and the reaction structure is shown in Table 3.

Table 3 Results of catalytic evaluation of halomethane carbonylation

Example 16

The reaction results of the carbonylation of dimethyl ether to produce methyl acetate at different reaction temperatures.

The catalyst used in the experiment was the 1# sample. 0.5 g of catalyst was loaded into a fixed bed reactor with an inner diameter of 8 mm, and it was raised to 400 °C at a rate of 2 °C/min under nitrogen atmosphere, kept for 2 hours, and then dropped to 400 °C in the same atmosphere. temperature reflex. The system pressure was increased to 2MPa with the reaction mixture, and the reaction gas was passed through the catalyst bed from top to bottom. Wherein the dimethyl ether feed space velocity is 1.0h ^-1 ; the molar ratio of carbon monoxide and dimethyl ether is 6:1, the carbon monoxide feed gas contains hydrogen, and the reaction temperatures are 170 ℃, 190 ℃, 210 ℃, 230 ℃, 300°C. The catalytic reaction was run for 10 hours and the results are shown in Table 4.

Table 4 Reaction results at different reaction temperatures

Reactor inlet temperature (℃) 170 190 210 230 300 Dimethyl ether conversion (%) 26.7 31.2 40.1 46.5 53.2 Methyl acetate selectivity (%) 98.6 99.2 98.9 98.5 98.2 Selectivity of other substances (%) 1.4 0.8 1.1 1.5 1.8

Example 17

The reaction results of the carbonylation of dimethyl ether to produce methyl acetate under different reaction pressures.

The catalyst used in the experiment was sample 1#, the reaction pressures were 1, 3, 5 and 15Mpa respectively, the reaction temperature was 200°C, and other operating procedures were the same as those in Example 16. The reaction was run for 10 hours and the results are shown in Table 5.

Table 5 Reaction results at different reaction pressures

Reaction pressure (MPa) 1 3 5 15 Dimethyl ether conversion (%) 16.8 42.5 62.4 72.1 Methyl acetate selectivity (%) 98.6 99.0 99.4 99.6 Selectivity of other substances (%) 1.4 1.0 0.6 0.4

Example 18

Results of the dimethyl ether carbonylation reaction at different dimethyl ether space velocities.

The catalyst used in the experiment was sample 1#, the feed mass space velocity of dimethyl ether was 0.1h ^-1 , 1.5h ^-1 , 1.75h ^-1 , 2.0h ^-1 , 2.5h ^-1 and 4h ^-1 , and the reaction temperature was 200°C, other operating conditions are the same as in Example 16, and the reaction results are shown in Table 6.

Table 6 Reaction results at different dimethyl ether space velocities

DME feed space velocity (h^-1) 0.1 1.5 1.75 2.0 4.0 Dimethyl ether conversion (%) 100 55.8 36.7 24.8 5.7 Methyl acetate selectivity (%) 99.7 99.6 99.5 99.6 99.3 Selectivity of other substances (%) 0.3 0.4 0.5 0.4 0.7

Example 19

Reaction results at different carbon monoxide to dimethyl ether molar ratios.

The catalyst used in the experiment is sample 1#, and the molar ratio of carbon monoxide to dimethyl ether is 0.1:1, 0.5:1, 1:1, 2:1, 5:1, 10:1, 15:1 and 25:1. The temperature was 200°C, other operating conditions were the same as those in Example 16, and the reaction results were shown in Table 7.

The reaction results of table 7 under different molar ratios of carbon monoxide and dimethyl ether

Example 20

Results of the carbonylation of dimethyl ether in the presence of an inert gas in the carbon monoxide-containing feed gas.

The catalyst used in the experiment is the 1# sample, the dimethyl ether feed space velocity is 0.5h ^-1 , the carbon monoxide-containing feed gas contains inactive gas, and the molar ratio of the carbon monoxide-containing feed gas to dimethyl ether is selected as 5:1, Other conditions are the same as in Example 13, and the reaction results are shown in Table 8.

Table 8 Reaction results of inert gas contained in carbon monoxide-containing raw material gas

Example 21

The reaction results of the carbonylation of methyl chloride to produce acetic acid/methyl acetate at different reaction temperatures.

The catalyst used in the experiment was the 5# sample. 1.0 g of the catalyst was loaded into a fixed-bed reactor with an inner diameter of 8 mm, and it was raised to 400 °C at a rate of 2 °C/min under a nitrogen atmosphere, kept for 2 hours, and then dropped to 400 °C in the same atmosphere. temperature reflex. The pressure of the system was raised to 2.5 MPa with the reaction mixture, and the reaction gas was passed through the catalyst bed from top to bottom. The feed space velocity of methyl chloride was 0.5 h ^-1 ; the molar ratio of carbon monoxide and methyl chloride was 20:1, and the reaction temperatures were 180° C., 230° C., 280° C. and 300° C., respectively. The catalytic reaction was run for 20 hours and the results are shown in Table 9.

The carbonylation reaction results of table 9 methyl chloride at different reaction temperatures

Reactor inlet temperature (℃) 180 230 280 300 Methyl chloride conversion (%) 15.6 26.7 45.6 71.9 Acetic acid + methyl acetate selectivity (%) 99.7 96.7 88.5 80.5 Selectivity of other substances (%) 0.3 3.3 11.5 19.5

Example 22

Results of the carbonylation of methyl chloride to produce acetic acid/methyl acetate at different reaction pressures.

The catalyst used in the experiment was the 14# sample, the reaction pressures were 1.5, 3.5, 5 and 15Mpa respectively, the reaction temperature was 260°C, and other operating procedures were the same as those in Example 21. The reaction was run for 20 hours and the results are shown in Table 10.

Table 10 Results of methyl chloride carbonylation reaction under different reaction pressures

Example 23

Reaction results at different carbon monoxide to methyl chloride molar ratios.

The molar ratios of carbon monoxide and methyl chloride were 0.1:1, 5:1, 10:1 and 25:1, the reaction temperature was 260° C., and other operating conditions were the same as in Example 21, and the reaction results were shown in Table 11.

Table 11 Reaction results of different molar ratios of carbon monoxide and methyl chloride

Carbon monoxide/chloromethane molar ratio 0.1:1 5:1 10:1 25:1 Methyl chloride conversion (%) 6.7 13.2 21.8 40.9 Acetic acid + methyl acetate selectivity (%) 86.1 90.1 98.2 98.8 Selectivity of other substances (%) 13.9 9.9 1.8 1.2

Example 24

Put 10 grams of NH ₄ -MOR (Si/Al=10) molecular sieves into 100 ml of tetraethylammonium hydroxide solution with a mass fraction of 3.0% (solid-to-liquid ratio of 1 g:10 ml), stir and mix evenly, at 50 ℃ , 100 °C and 150 °C under normal pressure for 48 hours, filtered, washed with deionized water, and dried to obtain solid samples. The prepared samples were calcined at 550°C for 4 hours in an air atmosphere to obtain catalysts 50#, 51# and 52#. And under the same conditions of Example 13, the performance of its dimethyl ether carbonylation to generate methyl acetate was investigated, and the details are shown in Table 12.

Table 12 Comparison results of dimethyl ether carbonylation performance of catalysts treated under unsealed and sealed conditions

The above are only some embodiments of the present application, and are not intended to limit the present application in any form. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Without departing from the scope of the technical solution of the present application, any changes or modifications made by using the technical content disclosed above are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims (10)

1. A method of preparing a molecular sieve catalyst, the method comprising:

(1) heating a material containing a mordenite molecular sieve and an organic alkali source to obtain an intermediate product;

(2) and roasting the intermediate product to obtain the molecular sieve based catalyst.

2. The method according to claim 1, wherein the organic base source is selected from organic amines; the organic amine is selected from at least one of unitary organic amine, binary organic amine and ternary organic amine;

preferably, the mono-organic amine is at least one selected from compounds having the formula shown in formula I:

wherein R is ¹ ，R ² ，R ³ Is independently selected from H, C ₁ ～C ₁₀ Any one of the alkyl groups of (a);

R ¹ ，R ² ，R ³ cannot be simultaneously H;

preferably, the mono-organic amine is selected from alkyl ammonium hydroxides; the alkyl ammonium hydroxide is selected from at least one of compounds having a chemical formula shown in formula II:

wherein R is ⁴ ，R ⁵ ，R ⁶ ，R ⁷ Independently selected from C ₁ ～C ₁₀ Any one of the alkyl groups of (1).

3. The method according to claim 1, wherein the heating conditions are: the temperature is 50-220 ℃, and the time is 5-100 hours;

preferably, the roasting conditions are as follows: the temperature is 450-650 ℃, and the time is 1.5-10 hours.

4. The preparation method of claim 1, wherein the mordenite molecular sieve has a silicon-aluminum atomic ratio of: Si/Al is 6-50;

preferably, the mordenite molecular sieve is selected from Na-MOR, NH ₄ At least one of-MOR, H-MOR molecular sieves.

5. The method according to claim 1, wherein the organic base source further comprises a solvent; the solvent is selected from water;

preferably, the mass content of the organic alkali in the organic alkali source is 0.5-99.9%;

preferably, the ratio of the addition amount of the mordenite molecular sieve and the organic alkali source is 1g:2 ml-1 g:20 ml.

6. A molecular sieve catalyst, characterized in that the molecular sieve catalyst comprises the molecular sieve catalyst obtained by the preparation method according to any one of claims 1 to 5.

7. A method for preparing acetic acid and/or methyl acetate is characterized in that a compound I and mixed gas containing carbon monoxide are contacted and reacted in the presence of a catalyst to obtain methyl acetate or acetic acid;

wherein the catalyst is selected from at least one of the molecular sieve catalyst of claim 6, the molecular sieve catalyst prepared by the process of any one of claims 1 to 5;

the compound I is selected from at least one of methanol, halogenated methane and dimethyl ether.

8. The method according to claim 7, wherein the reaction conditions are: the temperature is 150-320 ℃, the pressure is 0.5-25.0 MPa, and the time is 10-24 h;

preferably, the mass space velocity of the feed of the compound I is 0.05-5 h ^-1 。

9. The method according to claim 7, wherein the molar ratio of the carbon monoxide to the compound I is 0.1:1 to 50: 1;

preferably, the volume fraction of carbon monoxide in the mixed gas containing carbon monoxide is 20-100%.

10. The production method according to claim 7, wherein the mixed gas containing carbon monoxide further comprises an inert gas; the inactive gas is at least one selected from hydrogen, nitrogen, argon, carbon dioxide, methane and ethane.