Method for preparing acetal carbonyl compound

Abstract

The present application provides a method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol, which comprises a step in which a raw material acetal and a raw gas carbon monoxide go through a reactor loaded with a catalyst containing an acidic microporous silicoaluminophosphate molecular sieve, for carrying out a carbonylation reaction. In the method of the present invention, the conversion rate of the raw material acetal is high, and the selectivity of acetal carbonylation is high, and the catalyst life is long, and no additional solvent is needed in the reaction process, and the reaction condition is relatively mild, and the process is continuous, showing the potential for industrial application. Moreover, the product of acetal carbonyl compound can be used for producing ethylene glycol by hydrogenation followed by hydrolysis.

Claims

1. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol, which comprises a step in which a raw material acetal and carbon monoxide go through a reactor loaded with a catalyst for carrying out a carbonylation reaction; wherein the catalyst contains an acidic microporous silicoaluminophosphate molecular sieve; wherein the chemical composition of the acidic microporous silicoaluminophosphate molecular sieve is expressed as (Si.sub.xAl.sub.yP.sub.z)O.sub.2, and x is in a range from 0.01 to 0.60, and y is in a range from 0.2 to 0.60, and z is in a range from 0.2 to 0.60, and x+y+z=1; wherein the raw material acetal is expressed as R.sub.1O(CH.sub.2O).sub.nR.sub.2, and n is selected from 1, 2, 3 or 4, and R.sub.1 and R.sub.2 are independently selected from C.sub.1-C.sub.3 alkyls; wherein the acidic microporous silicoaluminophosphate molecular sieve is one or more molecular sieves selected from the molecular sieves with framework type of CHA, RHO, LEV, ERI, AEI or AFX.

2. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the acidic microporous silicoaluminophosphate molecular sieve ahas an 8-membered ring pore framework.

3. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the acidic microporous silicoaluminophosphate molecular sieve is one or more molecular sieves selected from SAPO-34, DNL-6, SAPO-35, SAPO-17, SAPO-18 or SAPO-56.

4. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the acidic microporous silicoaluminophosphate molecular sieve contains a metal; and the mass fraction of the metal element in the acidic microporous silicoaluminophosphate molecular sieve is in a range from 0% to 10%.

5. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 4, wherein the metal is located at the ion-exchange sites, in the pores and channels, on the surface and/or in the framework of the acidic microporous silicoaluminophosphate molecular sieve; and the metal is introduced by one or more methods selected from in-situ synthesis, impregnation or ion exchange.

6. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the catalyst contains a forming agent, and the mass fraction of the forming agent in the catalyst is in a range from 10% to 60%.

7. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the raw material acetal is CH.sub.3OCH.sub.2OCH.sub.3, C.sub.2H.sub.5OCH.sub.2OC.sub.2H.sub.5 or CH.sub.3O(CH.sub.2O).sub.2CH.sub.3, and the acetal carbonyl compound is one or more compounds selected from CH.sub.3O(CO)CH.sub.2OCH.sub.3, C.sub.2H.sub.5O(CO)CH.sub.2OC.sub.2H.sub.5, CH.sub.3O(CO)CH.sub.2OCH.sub.2OCH.sub.3 or CH.sub.3OCH.sub.2(CO)OCH.sub.2OCH.sub.3.

8. A method for preparing acetal carbonyl compound used as n intermediate for producing ethylene glycol according to claim 1, wherein the carbonylation reaction conditions are as follows: the reaction temperature is in a range from 60 C. to 140 C., and the reaction pressure is in a range from 1 MPa to 15 MPa, and the mass space velocity of the raw material acetal is in a range from 0.1 h.sup.1 to 10.0 h.sup.1, and the molar ratio of carbon monoxide to the raw material acetal is in a range from 2:1 to 20:1, and no solvent is added.

9. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the reactor is a continuous reactor which is selected from a fixed bed reactor, a tank reactor, a moving bed reactor or a fluidized bed reactor.

10. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 4, wherein the mass fraction of the metal element in the acidic microporous silicoaluminophosphate molecular sieve is in a range from 0% to 2%.

11. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 4, wherein the metal is one or more metals selected from copper, iron, gallium, silver, nickel, cobalt, palladium or platinum.

12. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 6, wherein the mass fraction of the forming agent in the catalyst is in a range from 10% to 30%.

13. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 6, wherein the forming agent is one or more compounds selected from alumina, silicon oxide or kaolin.

14. A method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol according to claim 1, wherein the carbonylation reaction conditions are as follows: the reaction temperature is in a range from 70 C. to 120 C., and the reaction pressure is in a range from 3 MPa to 10 MPa, and the mass space velocity of the raw material acetal is in a range from 0.5 h.sup.1 to 3 h.sup.1, and the molar ratio of carbon monoxide to the raw material acetal is in a range from 5:1 to 15:1, and no solvent is added.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 is the X-ray powder diffraction (XRD) spectra of the SAPO-34 molecular sieve prepared in Example 1 of the present invention.

(2) FIG. 2 is the scanning electron microscope (SEM) image of the SAPO-34 molecular sieve prepared in Example 1 of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENT

(3) The present invention refers to a method for preparing acetal carbonyl compound used as an intermediate for producing ethylene glycol, which comprises a step in which a raw material acetal and a raw material carbon monoxide go through a reactor loaded with a catalyst containing an acidic microporous silicoaluminophosphate molecular sieve, for carrying out a carbonylation reaction.

(4) Preferably, the acidic microporous silicoaluminophosphate molecular sieve is with an 8-membered ring pore framework.

(5) Preferably, the chemical composition of the acidic microporous silicoaluminophosphate molecular sieve is expressed as (Si.sub.xAl.sub.yP.sub.z)O.sub.2; x, y, z respectively represents the molar number of Si, Al, P, and x is in a range from 0.01 to 0.60, and y is in a range from 0.2 to 0.60, and z is in a range from 0.2 to 0.60, and x+y+z=1.

(6) Preferably, the acidic microporous silicoaluminophosphate molecular sieve is one or more molecular sieves selected from the molecular sieves with framework type of ABW, ACO, AEI, AEN, AFN, AFT, AFX, ANA, APC, APD, ATN, ATT, ATV, AWO, AWW, BIK, BRE, CAS, CHA, DOR, DFY, LAB, EDI, ERI, ESV, GIS, GOO, ITE, JBW, KFI, LEV, LTA, MER, MON, MTF, PAU, PHI, RHO, RTE, RTH, SAS, SAT, SAV, THO, TSC, VNI, YUG or ZON.

(7) Preferably, the acidic microporous silicoaluminophosphate molecular sieve is one or more molecular sieves selected from the molecular sieves with framework type of CHA, RHO, LEV, ERI, AEI or AFX.

(8) Preferably, the acidic microporous silicoaluminophosphate molecular sieve is one or more molecular sieves selected from SAPO-34, DNL-6, SAPO-35, SAPO-17, SAPO-18 or SAPO-56.

(9) Preferably, the acidic microporous silicoaluminophosphate molecular sieve contains a metal; and the mass fraction of the metal element in the acidic microporous silicoaluminophosphate molecular sieve is in a range from 0% to 10%.

(10) Preferably, the acidic microporous silicoaluminophosphate molecular sieve contains a metal; and the mass fraction of the metal element in the acidic microporous silicoaluminophosphate molecular sieve is in a range from 0% to 2%.

(11) Preferably, the metal is one or more metals selected from copper, iron, gallium, silver, nickel, cobalt, palladium or platinum.

(12) Preferably, the metal is located at the ion-exchange sites, in the pores and channels, on the surface and/or in the framework of the acidic microporous silicoaluminophosphate molecular sieve.

(13) Preferably, the metal is introduced by one or more methods selected from situ synthesis, impregnation or ion exchange.

(14) Preferably, the metals exist at ion-exchange sites as an ionic state, or exist in pores and channels or on the surface of the molecular sieve as a metallic oxide state, or are inset into the T atomic sites in the framework of the molecular sieve by isomorphous replacement.

(15) Preferably, the catalyst contains a forming agent, and the mass fraction of the forming agent in the catalyst is in a range from 10% to 60%.

(16) Preferably, the mass fraction of the forming agent in the catalyst is in a range from 10% to 30%.

(17) Preferably, the forming agent is one or more compounds selected from alumina, silicon oxide or kaolin.

(18) Preferably, the raw material acetal is expressed as R.sub.1O(CH.sub.2O).sub.nR.sub.2, and n is selected from 1, 2, 3 or 4, and R.sub.1 and R.sub.2 are independently selected from C.sub.1-C.sub.3 alkyls. More preferably, the raw material acetal is preferably CH.sub.3OCH.sub.2OCH.sub.3, C.sub.2H.sub.5OCH.sub.2OC.sub.2H.sub.5 or CH.sub.3O (CH.sub.2O).sub.2CH.sub.3.

(19) The product acetal carbonyl compound with the structural unit of O(CO)CH.sub.2O or OCH.sub.2(CO)O, is formed by inserting one or more carbanyl group CO into the structural unit of OCH.sub.2O in the molecular chain of raw material acetal R.sub.1O(CH.sub.2O).sub.nR.sub.2.

(20) The carbonylation process of acetal can be expressed as the following chemical reaction equations:
CH.sub.3OCH.sub.2OCH.sub.3+CO=CH.sub.3O(CO)CH.sub.2OCH.sub.3(I)
I
C.sub.2H.sub.5OCH.sub.2OC.sub.2H.sub.5+CO=C.sub.2H.sub.5O(CO)CH.sub.2OC.sub.2H.sub.5(II)
II
CH.sub.3O(CH.sub.2O).sub.2CH.sub.3+CO=CH.sub.3O(CO)CH.sub.2OCH.sub.2OCH.sub.3(III)
III
CH.sub.3O(CH.sub.2O).sub.2CH.sub.3+CO=CH.sub.3OCH.sub.2(CO)OCH.sub.2OCH.sub.3(IV)
IV

(21) Preferably, the acetal carbonyl compound is one or more compounds selected from the following compounds:

(22) CH.sub.3O(CO)CH.sub.2OCH.sub.3, C.sub.2H.sub.5O(CO)CH.sub.2OC.sub.2H.sub.5, CH.sub.3O(CO)CH.sub.2OCH.sub.2OCH.sub.3 or CH.sub.3OCH.sub.2(CO)OCH.sub.2OCH.sub.3.

(23) Preferably, the raw material carbon monoxide is obtained by separating from synthetic gas. In addition, in the method of the present invention, the feed gas can also be a mixed gas with volume content of carbon monoxide more than 50%, which may include hydrogen and one or more gases selected from or nitrogen, helium, argon, carbon dioxide, methane or ethane.

(24) Preferably, the reaction conditions are as follows: the reaction temperature is in a range from 60 C. to 140 C., and the reaction pressure is in a range from 1 MPa to 15 MPa, and the mass space velocity of the raw material acetal is in a range from 0.1 h.sup.1 to 10.0 h.sup.1, and the molar ratio of the raw gas carbon monoxide to the raw material acetal is in a range from 2:1 to 20:1, and no solvent is added.

(25) Preferably, the carbonylation reaction conditions are as follows: the reaction temperature is in a range from 70 C. to 120 C., and the reaction pressure is in a range from 3 MPa to 10 MPa, and the mass space velocity of the raw material acetal is in a range from 0.5 h.sup.1 to 3 h.sup.1, and the molar ratio of the raw material carbon monoxide to the raw material acetal is in a range from 5:1 to 15:1, and no solvent is added.

(26) In the reaction, at least one of the raw acetal or the product acetal carbonyl compound is in liquid phase, and the acidic microporous silicoaluminophosphate molecular sieve is in solid phase, and the feed gas carbon monoxide is in gas phase, and therefore the reaction process is a gas-liquid-solid three phases reaction.

(27) Preferably, the product acetal carbonyl compound can be further hydrogenated to prepare ethylene glycol ether. More preferably, the ethylene glycol ether is ethylene glycol monomethyl ether; and the ethylene glycol monomethyl ether can be hydrolyzed to prepare ethylene glycol.

(28) Preferably, the reactor is a continuous reactor which is selected from a fixed bed reactor, a tank reactor, a moving bed reactor or a fluidized bed reactor.

(29) Preferably, the reactor is one fixed bed reactor or more fixed bed reactors, to carry out a continuous reaction. The fixed bed reactor can be one or multiple. When multiple fixed bed reactors are used, the reactors can be connected in series, in parallel, or in combination of series and parallel.

EXAMPLES

(30) The analysis method and the calculation method of conversion rate and selectivity in the Examples are as follows:

(31) The constituent of the gas/liquid phase components were automatically analyzed by an Agilent7890 gas chromatograph equipped with an automatic sampler, an FID detector and FFAP capillary columns.

(32) In some Examples of the present invention, the conversion of acetal and the selectivity of acetal carbonyl compound were calculated on the basis of the carbon molar number of the acetal:
Percent conversion of acetal=[(carbon molar number of acetal in the feeding material)(carbon molar number of acetal in the discharging material)](carbon molar number of acetal in the feeding material)(100%)
Selectivity of acetal carbonyl compound=(carbon molar number of acetal carbonyl compound in the discharging material subtract the carbonyl groups)[(carbon molar number of acetal in the feeding material)(carbon molar number of acetal in the discharging material)](100%)

(33) The present invention is described in details by the following Examples, but the invention is not limited to these Examples.

Examples of Preparing the Catalyst

Example 1

(34) At room temperature, pseudo-boehmite was added into a phosphoric acid solution, stirring for 2h to obtain a homogeneous gel. Then silica sol and diethylamine (DEA) was added into the homogeneous gel, stirring for 3h to obtain a gel mixture with a molar ratio of 2.0 DEA:0.6 SiO.sub.2:1.0 Al.sub.2O.sub.3:0.8 P.sub.2O.sub.5:50 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 2 days at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-34 molecular sieve raw powder sample with chemical composition of (Si.sub.0.16Al.sub.0.48P.sub.0.36)O.sub.2. The SAPO-34 molecular sieve raw powder sample was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-34 molecular sieve. The X-ray powder diffraction spectra and the scanning electron microscope image of the acidic SAPO-34 molecular sieve were shown in FIG. 1 and FIG. 2. And then the acidic SAPO-34 molecular sieve was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 20%, to obtain a cylindrical catalyst A with a diameter of 3 mm and a length of 3 mm.

Example 2

(35) Aluminium isopropoxide, deionized water, phosphoric acid and tetraethoxysilane (TEOS) were mixed and stirred for 3h at room temperature to obtain a homogeneous gel. Then cetyl trimethyl ammonium bromide (CTAB) and diethylamine (DEA) solution were added into the homogeneous gel to obtain a gel mixture with a molar ratio of 2.0 DEA:1.0 Al.sub.2O.sub.3:0.8P.sub.2O.sub.5:0.4 TEOS:0.2 CTAB:100 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 1 day at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a DNL-6 molecular sieve raw powder sample with chemical composition of (Si.sub.0.14Al.sub.0.37P.sub.0.49)O.sub.2. The DNL-6 molecular sieve raw powder sample was calcined at 500 C. in air for 4 h to obtain an acidic DNL-6 molecular sieve. The acidic DNL-6 molecular sieve was molded using silicon oxide as a forming agent, and the mass fraction of the forming agent in the catalyst is 10%, to obtain a cylindrical catalyst B with a diameter of 3 mm and a length of 3 mm.

Example 3

(36) At room temperature, pseudo-boehmite was added into a phosphoric acid solution, stirring for 2h to obtain a homogeneous gel. Then silica sol and diethylamine (DEA) was added into the homogeneous gel, stirring for 3h to obtain a gel mixture with a molar ratio of 2.0 DEA:0.6 SiO.sub.2:1.0 Al.sub.2O.sub.3:0.8 P.sub.2O.sub.5:50 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 2 days at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-34 molecular sieve raw powder sample with chemical composition of (Si.sub.0.16Al.sub.0.4P.sub.0.36)O.sub.2. The SAPO-34 molecular sieve raw powder sample was ion-exchanged with 0.8 mol/L aqueous solution of ammonium nitrate at 80 C. for 3 times, to obtain an ammonium type SAPO-34 molecular sieve. The ammonium type SAPO-34 molecular sieve was ion-exchanged with 0.05 mol/L aqueous solution of copper nitrate to obtain a SAPO-34 molecular sieve modified by copper using ion-exchange method. The SAPO-34 molecular sieve modified by copper using ion-exchange method was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-34 molecular sieve with a copper mass fraction of 0.5%. And then the acidic SAPO-34 molecular sieve with a copper mass fraction of 0.5% was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 20%, to obtain a cylindrical catalyst C with a diameter of 3 mm and a length of 3 mm.

Example 4

(37) Aluminium isopropoxide, deionized water, phosphoric acid and tetraethoxysilane (TEOS) were mixed and stirred for 3h at room temperature to obtain a homogeneous gel. Then cetyl trimethyl ammonium bromide (CTAB) and diethylamine (DEA) solution were added into the homogeneous gel to obtain a gel mixture with a molar ratio of 2.0 DEA:1.0 Al.sub.2O.sub.3:0.8P.sub.2O.sub.5:0.4 TEOS:0.2 CTAB:100 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 1 day at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a DNL-6 molecular sieve raw powder sample with chemical composition of (Si.sub.0.14Al.sub.0.37P.sub.0.49)O.sub.2. The DNL-6 molecular sieve raw powder sample was equivalent-volume impregnated with a palladium nitrate aqueous solution to obtain a DNL-6 molecular sieve modified by palladium using equivalent-volume impregnation method. The DNL-6 molecular sieve modified by palladium using equivalent-volume impregnation method was calcined at 500 C. in air for 4 h to obtain an acidic DNL-6 molecular sieve with a palladium mass fraction of 1%. The acidic DNL-6 molecular sieve was molded using silicon oxide as a forming agent, and the mass fraction of the forming agent in the catalyst is 10%, to obtain a cylindrical catalyst D with a diameter of 3 mm and a length of 3 mm.

Example 5

(38) Pseudo-boehmite, silica sol, deionized water, phosphoric acid aqueous solution and hexamethyleneimine (HMI) were added to a beaker in sequence and mixed by stirring at room temperature to obtain a gel mixture with a molar ratio of 0.96 P.sub.2O.sub.5:1.0 Al.sub.2O.sub.3:1.0 SiO.sub.2:1.51 HMT:55.47 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 1 day at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-35 molecular sieve raw powder sample with chemical composition of (Si.sub.0.18Al.sub.0.46P.sub.0.36)O.sub.2. The SAPO-35 molecular sieve raw powder sample was equivalent-volume impregnated with a silver nitrate aqueous solution to obtain a SAPO-35 molecular sieve modified by silver using equivalent-volume impregnation method. The SAPO-35 molecular sieve modified by silver using equivalent-volume impregnation method was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-35 molecular sieve with a silver mass fraction of 0.1%. The acidic SAPO-35 molecular sieve was molded using kaolin as a forming agent, and the mass fraction of the forming agent in the catalyst is 15%, to obtain a cylindrical catalyst E with a diameter of 3 mm and a length of 3 mm.

Example 6

(39) Aluminium isopropoxide, silica sol, deionized water, phosphoric acid aqueous solution and cyclohexylamine (Cha) were added to a beaker in sequence and mixed by stirring at room temperature to obtain a gel mixture with a molar ratio of 0.11 SiO.sub.2:1 Al.sub.2O.sub.3:1 P.sub.2O.sub.5:1 Cha:50H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 1 day at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-17 molecular sieve raw powder sample with chemical composition of (Si.sub.0.14Al.sub.0.51P.sub.0.35).sub.2. The SAPO-17 molecular sieve raw powder sample was equivalent-volume impregnated with a nickel nitrate aqueous solution to obtain a SAPO-17 molecular sieve modified by nickel using equivalent-volume impregnation method. The SAPO-17 molecular sieve modified by nickel using equivalent-volume impregnation method was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-17 molecular sieve with a nickel mass fraction of 2%. The acidic SAPO-17 molecular sieve was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 30%, to obtain a cylindrical catalyst F with a diameter of 3 mm and a length of 3 mm.

Example 7

(40) Pseudo-boehmite, silica sol, deionized water, phosphoric acid aqueous solution and N,N-diisopropylethylamine (C.sub.8H.sub.19N) were added to a beaker in sequence and mixed by stirring at room temperature to obtain a gel mixture with a molar ratio of 0.2 SiO.sub.2:1.0 Al.sub.2O.sub.3:1.0 P.sub.2O.sub.5:1.6 C.sub.8H.sub.19N:55H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 3 days at 180 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-18 molecular sieve raw powder sample with 0.7 chemical composition of (Si.sub.0.11Al.sub.0.57P.sub.0.32)O.sub.2. The SAPO-18 molecular sieve raw powder sample was equivalent-volume impregnated with a gallium nitrate aqueous solution to obtain a SAPO-18 molecular sieve modified by gallium using equivalent-volume impregnation method. The SAPO-18 molecular sieve modified by gallium using equivalent-volume impregnation method was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-18 molecular sieve with a gallium mass fraction of 0.3%. The acidic SAPO-18 molecular sieve was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 20%, to obtain a cylindrical catalyst G with a diameter of 3 mm and a length of 3 mm.

Example 8

(41) Pseudo-boehmite, silica sol, deionized water, phosphoric acid aqueous solution and N,N,N,N-tetramethyl-1,6-hexamethylenediamine (TMHD) were added to a beaker in sequence and mixed by stirring at room temperature to obtain a gel mixture with a molar ratio of 2.0 TMHD:0.6 SiO.sub.2:0.8 Al.sub.2O.sub.3:P.sub.2O.sub.5:40 H.sub.2O. The gel mixture was put into a crystallization kettle with a polytetrafluoroethylene lining, and then crystallized for 3 days at 200 C. After finishing the crystallization and being cooled, the solid product was centrifugal separated, dried at 120 C., and then was put into a muffle furnace and calcined at 550 C. in air for 4 h to obtain a SAPO-56 molecular sieve raw powder sample with chemical composition of (Si.sub.0.10Al.sub.0.42P.sub.0.48)O.sub.2. The SAPO-56 molecular sieve raw powder sample was ion-exchanged with 0.8 mol/L aqueous solution of ammonium nitrate at 80 C. for 3 times, to obtain an ammonium type SAPO-56 molecular sieve. The ammonium type SAPO-56 molecular sieve was ion-exchanged with 0.04 mol/L aqueous solution of copper nitrate to obtain a SAPO-56 molecular sieve modified by copper using ion-exchange method. The SAPO-56 molecular sieve modified by copper using ion-exchange method was calcined at 500 C. in air for 4 h to obtain an acidic SAPO-56 molecular sieve with a copper mass fraction of 0.3%. And then the acidic SAPO-56 molecular sieve with a copper mass fraction of 0.3% was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 20%, to obtain a cylindrical catalyst H with a diameter of 3 mm and a length of 3 mm.

Comparative Example 1

(42) Y molecular sieve with Si/Al=2.3 was employed, which was purchased from the catalyst plant of Nankai University. The Y molecular sieve was ion-exchanged with 0.8 mol/L aqueous solution of ammonium nitrate at 80 C. for 3 times, to obtain an ammonium type Y molecular sieve. The ammonium type Y molecular sieve was ion-exchanged with 0.05 mol/L aqueous solution of copper nitrate to obtain a Y molecular sieve modified by copper using ion-exchange method. The Y molecular sieve modified by copper using ion-exchange method was calcined at 500 C. in air for 4 h to obtain an acidic Y molecular sieve with a copper mass fraction of 0.5%. And then the acidic Y molecular sieve with a copper mass fraction of 0.5% was molded using alumina as a forming agent, and the mass fraction of the forming agent in the catalyst is 20%, to obtain a cylindrical catalyst I with a diameter of 3 mm and a length of 3 mm.

Examples of Testing Catalyst Performance

Example 9

(43) 1.0 kg of Catalyst A was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 90 C., and then a fresh feed gas with a molar ratio of 7 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 15 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 0.1 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 10

(44) 1.0 kg of Catalyst B was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 60 C., and then a fresh feed gas with a molar ratio of 13 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 1 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 10 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 11

(45) 1.0 kg of Catalyst C was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 90 C., and then a fresh feed gas with a molar ratio of 7 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 15 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 0.1 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 12

(46) 1.0 kg of Catalyst D was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 60 C., and then a fresh feed gas with a molar ratio of 13 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 1 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 10 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 13

(47) 1.0 kg of Catalyst E was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 140 C., and then a fresh feed gas with a molar ratio of 2 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 6.5 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 3.0 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 14

(48) 1.0 kg of Catalyst F was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 140 C., and then a fresh feed gas with a molar ratio of 2 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 6.5 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 3.0 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 15

(49) 1.0 kg of Catalyst G was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 73 C., and then a fresh feed gas with a molar ratio of 10 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 2.0 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 0.3 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Example 16

(50) 1.0 kg of Catalyst H was loaded into a stainless steel fixed bed reactor with an inner diameter of 32 mm, activated at 500 C. for 4 hours under nitrogen gas at atmospheric pressure. The temperature was reduced to the reaction temperature (abbreviated as T) of 120 C., and then a fresh feed gas with a molar ratio of 15 CO:1 CH.sub.3OCH.sub.2OCH.sub.3 was introduced, and the pressure was increased to the reaction pressure (abbreviated as P) of 4.7 MPa, and the weight hourly space velocity (abbreviated as WHSV) of CH.sub.3OCH.sub.2OCH.sub.3 in the fresh feed gas was controlled as 0.5 h.sup.1. After the reaction was stable, the reaction products were analyzed by the gas chromatograph and the percent conversion of acetal and the single pass selectivity of acetal carbonyl compound were calculated. The results were shown in Table 1.

Comparative Example 2

(51) The experimental conditions were same as Example 11, except that the Catalyst C was changed to the Catalyst I. The results were shown in Table 1.

(52) TABLE-US-00001 TABLE 1 Results of the carbonylation reaction of acetal Percent Selectivity of the Single pass conversion of acetal carbonyl life of the the acetal compound catalyst Catalyst (%) (%) (days) Example 9 A 100 93.2 430 Example 10 B 100 92.3 410 Example 11 C 100 95.8 450 Example 12 D 100 94.1 430 Example 13 E 100 95.6 500 Example 14 F 100 96.3 510 Example 15 G 100 97.8 550 Example 16 H 100 96.1 530 Comparative I 38 72.5 19 Example 2

(53) The present invention has been described in detail as above, but the invention is not limited to the detailed embodiments described in this text. Those skilled in the art will understand that other changes and deformations can be made without deviating from the scope of the invention. The scope of the invention is limited by the appended claims.