CN112939763A

CN112939763A - Method for preparing acetic acid from methyl halide

Info

Publication number: CN112939763A
Application number: CN201911261756.0A
Authority: CN
Inventors: 刘红超; 房旭东; 朱文良; 刘中民; 文富利; 刘世平; 马现刚; 刘勇
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2019-12-10
Filing date: 2019-12-10
Publication date: 2021-06-11
Anticipated expiration: 2039-12-10
Also published as: CN112939763B

Abstract

The invention provides a method for preparing acetic acid from methyl halide, which at least comprises the following steps: contacting a raw material gas containing methyl halide and carbon monoxide with a solid acid catalyst, and reacting to obtain acetic acid; the solid acid catalyst comprises an acidic zeolite molecular sieve. The invention takes the methyl halide as the raw material, realizes the directional conversion of the methyl halide to generate the acetic acid under the gas-solid phase condition by acid catalysis for the first time, and opens up a new path for preparing the chemical with high added value by methane conversion.

Description

Method for preparing acetic acid from methyl halide

Technical Field

The invention relates to a method for preparing acetic acid from methyl halide, belonging to the field of energy catalytic conversion.

Background

The continuous increase in energy demand and the urgent desire for improvement in environmental quality have made global energy development face unprecedented challenges. The 'efficient conversion and clean utilization' of energy is an inevitable choice in the energy development process. Methane is a main component of natural gas, shale gas and combustible ice, and is an important component of energy consumption, and efficient conversion of methane is continuously concerned by researchers. The methane molecular space structure is a regular tetrahedron and has Td quadruple symmetry; the average bond energy of four C-H bonds is 414kJ/mol, and the dissociation energy of the first C-H bond is as high as 435kJ/mol, so that the methane has extremely high chemical stability and is difficult to activate. The further conversion of methane to chemicals via methyl halide is thermodynamically favored. In the case of the conversion of methyl chloride into ethylene, the Δ H and Δ G of methyl chloride at 400 ℃ under normal pressure were 36.368KJ/mol and-54.571 KJ/mol, respectively. Therefore, the preparation of high value-added chemicals from methane via methyl halide has received attention from researchers.

In the research of chemicals, the conversion of methyl halide to oxygen-containing compounds is an important research direction. Methyl halide can be hydrolyzed or carbonylated to form oxygenates: hydrolyzing to obtain methanol or dimethyl ether; acetic acid may be produced by a carbonylation reaction. Acetic acid is an important basic chemical raw material and is widely applied to the synthesis of medicines, synthetic fibers, light industry, textiles, leather, pesticides, explosives, rubber and metal processing, foods and fine organic chemicals.

In the research reports of preparing acetic acid from methyl halide, noble metal is required to be used as a catalyst, and an iodine-containing compound is required to be added as an auxiliary agent. Because the precious metal reserves are limited and the price is high, the development of a non-precious metal catalytic system has important industrial application value and is also focused by researchers.

Disclosure of Invention

According to one aspect of the present application, a method for preparing acetic acid from methyl halide is provided, wherein acetic acid can be directly generated on a zeolite molecular sieve catalyst based on methyl halide as a raw material. The methyl halide of the method is derived from methane, and the methane is the main component of natural gas, shale gas and combustible ice. The acetic acid is generated by the reaction of the methyl halide under the condition of zeolite molecular sieve catalyst, which overcomes the defects of harsh methane conversion condition, low product selectivity and the like. The method for producing acetic acid by using methyl halide is in a gas-solid phase and takes non-noble metal as a catalyst, the process is simple, the catalyst is easy to obtain and low in cost, and the method has an important industrial application prospect.

The method uses a catalyst which does not contain noble metals and does not need to add iodine-containing compounds; the reaction system is a gas-solid reaction, the process is simple, and the method has wide application prospect.

According to one aspect of the present application, there is provided a process for the production of acetic acid from methyl halide, the process at least comprising: raw material gas containing methyl halide and carbon monoxide is contacted with a solid acid catalyst for reaction to obtain acetic acid.

Optionally, the solid acid catalyst comprises an acidic zeolitic molecular sieve.

Optionally, the methyl halide is at least one of methyl chloride, methyl bromide and methyl iodide.

Alternatively, the methyl chloride comprises methyl chloride, methylene chloride.

Optionally, the methyl bromide comprises methyl bromide and methyl bromide.

Dibromomethane alternatively, the methyl iodide comprises monoiodomethane, diiodomethane.

Optionally, the mass content of the acidic zeolite molecular sieve in the solid acid catalyst is 50-100%.

Optionally, the solid acid catalyst further comprises a matrix; the matrix comprises at least one of alumina, silica, kaolin and magnesia.

The acidic zeolitic molecular sieve may be prepared by any suitable method known in the art and is not limited in its preparation herein. A preferred method for preparing the acidic zeolitic molecular sieve is described below: putting Na type molecular sieve into 0.5-1 mol/L NH₄NO₃And (2) carrying out ion exchange in the aqueous solution at the room temperature of 90 ℃ for 0.5-10 h, washing with deionized water, repeating the steps for 1-3 times, drying at the temperature of 80-150 ℃, and roasting at the temperature of 500-600 ℃ to obtain the acid type zeolite molecular sieve.

Optionally, the acidic zeolite molecular sieve is selected from at least one of an acidic zeolite molecular sieve having a CHA structure, an acidic zeolite molecular sieve having an EMT structure, an acidic zeolite molecular sieve having an ETL structure, an acidic zeolite molecular sieve having a FAU structure, an acidic zeolite molecular sieve having a FER structure, an acidic zeolite molecular sieve having an MFI structure, an acidic zeolite molecular sieve having an MFS structure, an acidic zeolite molecular sieve having an MOR structure, an acidic zeolite molecular sieve having an MTF structure, an acidic zeolite molecular sieve having an MWW structure, an acidic zeolite molecular sieve having a TON structure.

Optionally, the silicon-aluminum atomic ratio of the acidic zeolite molecular sieve is 5-120.

Optionally, the reaction conditions are: the reaction temperature is 120-300 ℃; the reaction pressure is 0.2-20 MPa.

Preferably, the reaction temperature is 140-280 ℃; the reaction pressure is 2.0-15 MPa.

Optionally, the upper limit of the reaction temperature is selected from 160 ℃, 200 ℃, 240 ℃, 280 ℃, 300 ℃; the lower limit is selected from 140 deg.C, 180 deg.C, 220 deg.C, 260 deg.C, and 280 deg.C.

Alternatively, the upper limit of the reaction pressure is selected from 1MPa, 5MPa, 8MPa, 12MPa, 15MPa, 20MPa and the lower limit is selected from 0.2MPa, 1MPa, 5MPa, 8MPa, 12MPa, 15 MPa.

Optionally, the mass space velocity of the methyl halide is 0.001-2.0 h^-1(ii) a The molar ratio of carbon monoxide to methyl halide is 1: 1-100: 1.

preferably, the mass space velocity of the methyl halide is 0.1-2.0 h^-1(ii) a The molar ratio of carbon monoxide to methyl halide is 2: 1-90: 1.

preferably, the reaction temperature is 160-280 ℃; the reaction pressure is 2.0-15.0 MPa.

Preferably, the molar ratio of carbon monoxide to methyl halide is 3: 1-100: 1.

alternatively, the upper mass space velocity limit of the methyl halide is selected from 0.1h^-1、0.3h^-1、0.5h^-1、1h^-1、1.5h^-1、2h^-1The lower limit is selected from 0.001h^-1、0.1h^-1、0.3h^-1、0.5h^-1、1h^-1、1.5h^-1。

Optionally, the upper limit of the molar ratio of carbon monoxide to methyl halide is selected from 10: 1. 20: 1. 50: 1. 60: 1. 80: 1. 100, and (2) a step of: 1, lower limit selected from 1: 1. 10: 1. 20: 1. 50: 1. 60: 1. 80: 1.

optionally, the feed gas further comprises gas I; the gas I is at least one selected from hydrogen, nitrogen, helium, argon and carbon dioxide.

Optionally, the feed gas consists of methyl halide and a gas II comprising carbon monoxide; the gas II also comprises at least one of hydrogen, nitrogen, helium, argon and carbon dioxide; the volume content of the carbon monoxide in the gas II is 50-100%.

Optionally, the upper limit of the volume content of the carbon monoxide in the gas II is selected from 80%, 95%, 97.4%, 100%; the lower limit is selected from 50%, 80%, 95%, 97.4%.

The solid acid catalyst comprising the matrix can be prepared by any suitable method known in the art, and the preparation method is not limited herein. One preferred method of preparing the solid acid catalyst containing matrix is as follows: mixing and mixing the acidic zeolite molecular sieve, the matrix and sesbania powder according to a certain proportion, adding nitric acid with the concentration of 10% for kneading, forming in a strip extrusion mode, and roasting at 500-600 ℃ to obtain the solid acid catalyst containing the matrix.

Optionally, the reaction is carried out in a reactor; the reactor includes at least one of a fixed bed reactor, a fluidized bed reactor, and a moving bed reactor.

The skilled person can select a suitable reactor according to the actual production needs. Preferably, the reactor is a fixed bed reactor.

The beneficial effects that this application can produce include:

1) the method for producing acetic acid provided by the application adopts the solid acid catalyst containing the acidic zeolite molecular sieve, and gets rid of the existing reported precious metal catalyst route;

2) the method for producing acetic acid provided by the application is a heterogeneous catalytic reaction system, is simple in process, easy to separate, low in energy consumption and wide in application prospect.

Drawings

Figure 1 is an XRD pattern of the hydrogen form of the molecular sieve sample prepared in example 1.

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 analysis method in the examples of the present application is as follows:

in the examples, the conversion of methyl halide was calculated by internal standard method, and the selectivity of the product was calculated by normalization method:

methyl halide conversion rate [ (mole number of methyl halide carbon in raw material gas) - (mole number of methyl halide carbon in product) ]/(mole number of methyl halide carbon in raw material gas) × (100%)

Product selectivity ═ product carbon moles ÷ product organic carbon moles sum × 100%

The molecular sieve carrier raw material source is as follows: the molecular sieve raw materials used in the experiment are partially directly purchased commercially, partially synthesized according to the literature, and the specific sources and the names of the molecular sieve carriers are shown in the table 1.

TABLE 1 sources and Si/Al ratios of different catalysts

Molecular sieve raw material	Molecular sieve topology	Source	Acquisition mode	Si/Al ratio
					HSAPO-34	CHA	Dalian Chemical Physics Inst.	Synthesis of
NaSSZ-13	CHA	South China Kai catalyst plant	Purchasing	15
					NaEMT	EMT	Dalian Chemical Physics Inst.	Synthesis of	4
Na-EU-12	ETL	Dalian Chemical Physics Inst.	Synthesis of	10
					NaY	FAU	South China Kai catalyst plant	Purchasing		5
NaZSM-35	FER	Olympic catalyst plant	Purchasing	79
					HZSM-5	MFI	South China Kai catalyst plant	Purchasing	50
Na-ZSM-57	MFS	Dalian Chemical Physics Inst.	Synthesis of	20
					NaMOR	MOR	South China Kai catalyst plant	Purchasing	15
Na-MCM-22	MWW	Dalian Chemical Physics Inst.	Synthesis of	50
					Na-MCM-35	MTF	Dalian Chemical Physics Inst.	Synthesis of	100
Na-ZSM-22	TON	South China Kai catalyst plant	Purchasing							30

Synthesis of NaEMT reference Science, 2012356 (6): 70-73 and 'preparation, secondary synthesis and modification of molecular sieve' in 'molecular sieve and porous material chemistry': 2004: 416-466;

for synthesizing HSAPO-34, refer to the synthesis method of HSAPO-34 in methanol to olefin;

Na-EU-12 synthesis references Angew. chem. int. Ed.2016,55, 7369-7373 and "preparation, secondary synthesis and modification of molecular sieves" in molecular sieves and porous materials chemistry ": 2004: 416-466;

synthesis of Na-ZSM-57 references j.catal.2000,196, 158-166;

Na-MCM-22 synthesis references Zeolite, 1995,15,1, 2-8;

for the synthesis of Na-MCM-35, refer to chem.Mater.1999,11,2919-2927.

Example 1 catalyst preparation

Preparation of acidic zeolite molecular sieves

Passing the Na-type molecular sieve in Table 1 through NH₄NO₃Ion exchange, drying and roasting to obtain the hydrogen type molecular sieve.

Preparation of HMOR: in a hydrothermal synthesis kettle, adding NaMOR molecular sieve powder into pre-prepared 1mol/L NH₄NO₃In the aqueous solution, the solid-liquid mass ratio is 1:10, the exchange reaction is carried out for 2h at 80 ℃ under the stirring state, and the solution is subjected to vacuum filtration and washing by water. After 3 times of continuous exchange reaction, the product was dried at 120 ℃ overnight and calcined at 550 ℃ for 4 hours to obtain the desired catalyst sample HMOR.

The steps for preparing the acid zeolite molecular sieves by using other Na-type molecular sieves in the table 1 are the same as the reaction conditions and the steps for preparing the HMOR molecular sieves by using the NaMOR molecular sieve, and only corresponding molecular sieve raw materials are needed to be changed.

Then, the prepared hydrogen type sample is subjected to XRD (X-ray diffraction) spectrum analysis:

the phase of the hydrogen form of the sample was analyzed using an X-ray diffractometer model PANALYTICAL X' Pert PRO, the Netherlands. Sample analysis conditions: using Cu, K alpha rays

Graphite monochromator, Ni filtering, tube voltage of 40kV, tube current of 40mA, scanning speed of 5 DEG/min and scanning range of 5-60 deg. Fig. 1 is an XRD pattern of the hydrogen form molecular sieve sample prepared in example 1, and it can be seen from fig. 1 that the hydrogen form sample prepared retains typical characteristic peaks, indicating that the sample is not damaged during the preparation process.

Preparation of matrix-containing samples

The formed hydrogen type sample containing the matrix is prepared by adopting a strip extrusion forming method.

In this example, a substrate-containing hydrogen type sample was prepared, as represented by an HZSM-5(Si/Al ═ 50) sample, and the preparation of the substrate-containing sample using the other hydrogen type molecular sieves in table 1 was similar to that of the HZSM-5(Si/Al ═ 50) sample, and the details thereof are omitted.

Preparation of HZSM-5 molecular sieve containing alumina matrix: 50g of raw material sample HZSM-5 and 50g of alumina are fully mixed, 10 wt% of nitric acid is added for kneading, and the kneaded dough-shaped sample is extruded and formed by a strip extruder. Drying the extruded sample at 120 ℃, and roasting at 550 ℃ for 4h to obtain the acidic zeolite molecular sieve containing the matrix, wherein the sample is marked as HZ5-AO 5.

Preparation of HZSM-5 molecular sieve containing kaolin matrix: 80g of HZSM-5 was mixed with 20g of kaolin. Adding 5-15 wt% of nitric acid for kneading, and extruding the kneaded dough-shaped sample through a strip extruding machine for strip extrusion molding. The extruded sample is dried at 120 ℃ and roasted at 550 ℃ for 4h to obtain the acidic zeolite molecular sieve containing the matrix, and the sample is marked as HZ 8-K2.

Preparation of HZSM-5 molecular sieve containing magnesium oxide matrix: 80g of HZSM-5 was mixed with 20g of magnesium oxide. Adding 5-15 wt% of nitric acid for kneading, and extruding the kneaded dough-shaped sample through a strip extruding machine for strip extrusion molding. The extruded sample is dried at 120 ℃ and roasted at 550 ℃ for 4h to obtain the acidic zeolite molecular sieve containing the matrix, and the sample is marked as HZ8-MO 2.

Preparing an HZSM-5 molecular sieve containing a mixed matrix of silicon oxide, aluminum oxide and magnesium oxide: 80g of HZSM-5 was mixed with 20g of a mixture containing silica, alumina and magnesia. Wherein, the ratio of silicon oxide: alumina: the mass ratio of magnesium oxide is 2: 2: 1. adding 5-15 wt% of nitric acid for kneading, and extruding the kneaded dough-shaped sample through a strip extruding machine for strip extrusion molding. The extruded sample is dried at 120 ℃ and roasted at 550 ℃ for 4h to obtain the acidic zeolite molecular sieve containing the matrix, and the sample is marked as HZ8-SAM 2.

For the preparation of other acidic zeolite molecular sieves, matrix-containing samples can be prepared according to the above method according to actual needs. Typical samples were prepared as shown in table 2.

TABLE 2 sample number and sample composition

Example 2 preparation of acetic acid from methyl chloride over different catalysts

1g of each solid acid catalyst shown in Table 2 was charged in a fixed bed reactor having an inner diameter of 10mm and a quartz tube liner (inner diameter of 6mm) and heated to 550 ℃ at 5 ℃/min under a nitrogen atmosphere for 4 hours, and then the reaction temperature was lowered to 250 ℃ under a nitrogen atmosphere and the pressure of the reaction system was raised to 2MPa with CO. The reaction raw materials pass through the catalyst bed layer from top to bottom. Wherein the mass space velocity of the chloromethane feed is 0.15h^-1(ii) a Carbon monoxide andthe molar ratio of methyl chloride is 20:1, the catalytic reaction is carried out for 1 hour under the condition that the reaction temperature is 250 ℃, and the reaction result is shown in Table 3.

TABLE 3 results of the reactions on different catalysts

Catalyst and process for preparing same	Methyl chloride conversion (%)	Acetic acid selectivity (%)	Other oxygenates Selectivity (%)	Hydrocarbons (%)
					H-1#	66.42	20.00％	5.30％	74.700％
H-2#	42.3	68.00％	6.40％	25.600％
					H-3#	56.7	56.70％	2.00％	41.300％
H-4#	25.7	93.80％	2.00％	4.200％
					H-5#	40.5	10.50％	1.20％	88.300％
H-6#	48.8	45.60％	4.30％	50.100％
					H-7#	60.2	20.50％	2.30％	77.200％
H-8#	38.6	78.50％	1.20％	20.300％
					H-9#	32.8	92.20％	5.50％	2.300％
H(m)-10#	22.5	91.20％	6.70％	2.100％
					H(m)-11#	16.9	92.90％	5.80％	1.300％
H(m)-12#	23.8	93.80％	5.20％	1.000％
					H(m)-13#	22.5	92.40％	4.80％	2.800％
H(m)-14#	21.5	91.80％	5.20％	3.000％
					H-15#	30..8	68.30％	2.30％	29.400％
H-16#	8.9	72.30％	1.80％	25.900％
					H-17#	52.1	85.70％	1.90％	12.400％

As can be seen from Table 3, the objective of producing acetic acid by converting methyl chloride was achieved by using an acidic zeolite molecular sieve.

Comparative example 1

In the absence of carbon monoxide, under otherwise identical conditions as in example 1, methyl chloride reacted over the catalyst of Table 2, the acetic acid selectivity was zero.

EXAMPLE 3 direct conversion of methyl chloride to acetic acid at different reaction temperatures

The catalyst used was H-9# sample, the reaction temperature was 150 ℃ and 300 ℃ respectively, and the other reaction conditions were the same as in example 1. The results of the catalytic reaction for 1 hour are shown in Table 4.

TABLE 4 reaction results at different reaction temperatures

Reactor temperature (. degree.C.)	150	180	220	280	300
						Methyl chloride conversion (%)	2.8	6.8	25.7	42.8	68.9
Acetic acid selectivity (%)	99.8	98.8	95.8	87.8	50.9
						Other oxygenates Selectivity (%)	0.2	1.1	2.8	6.8	35.9
Hydrocarbon selectivity (%)	0.00	0.10	1.40	5.40	13.20

As can be seen from table 4, the temperature has an important influence on the production of acetic acid from methyl chloride, with increasing temperature increasing the methyl chloride conversion, but with increasing temperature above 280 ℃ the selectivity to acetic acid decreases.

EXAMPLE 4 direct conversion of methyl chloride to acetic acid at different reaction pressures

The catalyst used was H-9# sample, the reaction pressures were 0.2MPa, 5.0MPa, 15MPa and 20MPa, respectively, and the results of 1-hour reaction run under the same conditions as in example 1 are shown in Table 5.

TABLE 5 results of reactions at different reaction pressures

Reaction pressure (MPa)	0.2	5	15	20
					Methyl chloride conversion (%)	8.8	46.7	65.8	70.8
Acetic acid selectivity (%)	90.8	92.8	93.8	94.5
					Other oxygenates Selectivity (%)	5.7	4.1	2.8	3.7
Hydrocarbon selectivity (%)	3.50	3.10	3.40	1.80

As can be seen from table 5, the increase in reaction pressure helps to promote the reaction of methyl chloride conversion to acetic acid, and the higher the reaction pressure, the higher the conversion and the higher the acetic acid selectivity.

Example 5 preparation of acetic acid by direct conversion of methyl chloride at different methyl chloride Mass airspeeds

The catalyst used was H-9# sample, and the mass space velocities of methyl chloride were 0.02, 0.1, 0.5, 1, and 4H, respectively^-1Otherwise, the reaction was carried out under the same conditions as in example 1 for 1 hour, and the results are shown in Table 6.

TABLE 6 reaction results at different chloromethane mass airspeeds

Chloromethane mass space velocity (h)^-1)	0.02	0.1	0.5	1	4
						Methyl chloride conversion (%)	99.5	45.2	10.2	6.2	1.23
Acetic acid selectivity (%)	65.7	85.1	92.5	92.8	92.8
						Other oxygenates Selectivity (%)	30.7	10.0	5.5	5.2	5.1
Hydrocarbon selectivity (%)	3.6	4.9	2.0	2.0	2.1

As can be seen from table 6, the higher the mass space velocity of methyl chloride, the lower the methyl chloride conversion, but the acetic acid selectivity increased first and then stabilized.

EXAMPLE 6 preparation of acetic acid by direct conversion of methyl chloride at different molar ratios of carbon monoxide to methyl chloride

The catalyst used was H-9# sample, the molar ratios of CO and methyl chloride were 0.05, 1, 6, 40, 80 and 100, respectively, the conditions were otherwise the same as in example 1, and the results of 1 hour of reaction run are shown in Table 7.

TABLE 7 reaction results for different molar ratios of carbon monoxide to methyl chloride

CO/CH₃Cl	0.05:1	1:1	6:1	40:1	80:1	100:1
							Methyl chloride conversion (%)	1.8	4.5	12.2	38.9	49.8	65.3
Acetic acid selectivity (%)	65.3	73.2	89.5	93.1	94.1	94.0
							Other oxygenates Selectivity (%)	10.3	6.5	4.5	3.3	3.2	3.3
Hydrocarbon selectivity (%)	24.4	20.3	6	3.6	2.7	2.7

As can be seen from table 7, the ratio of carbon monoxide to methyl chloride has an important effect on the conversion of methyl chloride, the higher the ratio, the higher the conversion of methyl chloride and the higher the selectivity for acetic acid.

Example 7 preparation of acetic acid by direct conversion of monochloromethane when the carbon monoxide feed gas contains any one or more of hydrogen, nitrogen, helium, argon, carbon dioxide and the like

The catalyst used was H-9# sample, the CO content is shown in Table 8, the conditions are the same as in example 1, and the results of 1 hour of reaction run are shown in Table 8.

TABLE 8 results of reactions with carbon monoxide feed gas containing other gases

As can be seen from table 8, an increase in impurity gases in carbon monoxide directly leads to a decrease in the ratio of carbon monoxide to methyl chloride, and thus to a decrease in the conversion of methyl chloride.

EXAMPLE 8 conversion of various methyl halides into starting materials for the production of acetic acid

When the catalyst was H-9# and the halogenated methanes were methyl bromide, methyl iodide and a mixture, respectively, the reaction was carried out for 1 hour under the same conditions as in example 1, and the results are shown in Table 9.

TABLE 9 results of reactions starting from different methyl halides

As is clear from Table 9, when an acidic zeolite molecular sieve is used as a catalyst, monohalomethane or dihalomethane can be oriented to produce acetic acid having a high added value.

Example 9 direct preparation of acetic acid from methyl halide in different reactors

The catalyst used was H-9# sample, and the reaction was carried out for 1 hour under the same conditions as in example 1 using a fixed bed, a fluidized bed and a moving bed, respectively, and the results are shown in Table 10.

TABLE 10 results of different reactor reactions

As can be seen from Table 9, the conversion of methyl halide to acetic acid was achieved using different reactor types.

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

1. A process for preparing acetic acid from methyl halide, characterized in that it comprises at least: contacting a raw material gas containing methyl halide and carbon monoxide with a solid acid catalyst, and reacting to obtain acetic acid;

the solid acid catalyst includes an acidic zeolite molecular sieve.

2. The method for preparing acetic acid from methyl halide according to claim 1, wherein the methyl halide is at least one of methyl chloride, methyl bromide and methyl iodide.

3. The method for preparing acetic acid from methyl halide according to claim 1, wherein the mass content of the acidic zeolite molecular sieve in the solid acid catalyst is 50-100%.

4. The process for producing acetic acid from methyl halide according to claim 3, wherein the solid acid catalyst further comprises a substrate;

the matrix comprises at least one of alumina, silica, kaolin and magnesia.

5. The method for producing acetic acid from methyl halide according to claim 1, wherein the acidic zeolite molecular sieve is selected from at least one of acidic zeolite molecular sieves having a CHA structure, acidic zeolite molecular sieves having an EMT structure, acidic zeolite molecular sieves having an ETL structure, acidic zeolite molecular sieves having a FAU structure, acidic zeolite molecular sieves having a FER structure, acidic zeolite molecular sieves having an MFI structure, acidic zeolite molecular sieves having an MFS structure, acidic zeolite molecular sieves having an MOR structure, acidic zeolite molecular sieves having an MTF structure, acidic zeolite molecular sieves having an MWW structure, acidic zeolite molecular sieves having a TON structure;

the silicon-aluminum atomic ratio of the acidic zeolite molecular sieve is 5-120.

6. The process for preparing acetic acid from methyl halide according to claim 1, wherein the reaction conditions are as follows: the reaction temperature is 120-300 ℃; the reaction pressure is 0.2-20 MPa;

7. The method for preparing acetic acid from methyl halide according to claim 1, wherein the mass space velocity of methyl halide is 0.001-2.0 h^-1(ii) a The molar ratio of carbon monoxide to methyl halide is 0.05: 1-100: 1;

8. the method for preparing acetic acid from methyl halide according to claim 1, wherein the feed gas further comprises gas I;

the gas I is at least one selected from hydrogen, nitrogen, helium, argon and carbon dioxide.

9. The process for producing acetic acid from methyl halide according to claim 1, wherein the feed gas is composed of methyl halide and a gas II containing carbon monoxide;

the gas II also comprises at least one of hydrogen, nitrogen, helium, argon and carbon dioxide;

the volume content of the carbon monoxide in the gas II is 50-100%.

10. The process for preparing acetic acid from methyl halide according to claim 1, wherein the reaction is carried out in a reactor;

the reactor includes at least one of a fixed bed reactor, a fluidized bed reactor, and a moving bed reactor.