CN103539645B - Preparation method of polymethoxy methylal - Google Patents

Preparation method of polymethoxy methylal Download PDF

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CN103539645B
CN103539645B CN201210240163.8A CN201210240163A CN103539645B CN 103539645 B CN103539645 B CN 103539645B CN 201210240163 A CN201210240163 A CN 201210240163A CN 103539645 B CN103539645 B CN 103539645B
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catalyzer
grams
molecular sieve
sio
hours
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CN103539645A (en
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何欣
袁志庆
滕加伟
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/48—Preparation of compounds having groups
    • C07C41/50—Preparation of compounds having groups by reactions producing groups
    • C07C41/56—Preparation of compounds having groups by reactions producing groups by condensation of aldehydes, paraformaldehyde, or ketones
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
    • B01J2229/10—After treatment, characterised by the effect to be obtained
    • B01J2229/14—After treatment, characterised by the effect to be obtained to alter the inside of the molecular sieve channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
    • B01J2229/30—After treatment, characterised by the means used
    • B01J2229/38—Base treatment

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Catalysts (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

The invention relates to a preparation method of polymethoxy methylal, which mainly solves the problem of corrosiveness of the catalyst in the prior art. The method comprises the following step: contacting raw materials methanol or dimethyl ether and formaldehyde or trioxymethylene in a mol ratio of 1:(0.1-10) with a catalyst to react at the reaction temperature of 50-200 DEG C under the reaction pressure of 0.1-10MPa to obtain the polymethoxy methylal, wherein the catalyst is a ZSM-5 molecular sieve of which the crystal grain diameter is smaller than or equal to 5 micrometers, the ZSM-5 molecular sieve is treated in a 0.01-2 mol/L alkali solution at 30-100 DEG C for 0.1-10 hours, and the weight ratio of the alkali solution to the molecular sieve is 1-20. The technique scheme provided by the invention well solves the problem, and can be used for industrial production of polymethoxy methylal.

Description

The preparation method of polymethoxy methylal
Technical field
The present invention relates to a kind of preparation method of polymethoxy methylal.
Background technology
(Chinese also can be polyoxymethylene dimethyl ether to polymethoxy methylal, polyoxymethylene dimethyl ethers, polymethoxy dimethyl ether, polyoxymethylene dimethyl ethers, polymethoxy dimethyl ether, polyoxy methylene dimethyl ether etc.), i.e. polyoxymethylene dimethyl ethers (PODE), it is the common name of a class material, and its molecular structural formula is CH 3o (CH 2o) ncH 3, there is higher cetane value (cetane number, CN.During n=3 ~ 8, CN>76) and oxygen level (42 ~ 49%).When the value of n is 3 ~ 8, its physical and chemical performance, combustionproperty and diesel oil closely, can be used as diesel-dope, and the addition in diesel oil can reach 30% (v/v), keeps higher cetane value and combustionproperty simultaneously.The oilness of diesel oil can be improved, reduce combustion fumes and generate, diesel oil combustion position within the engine can be improved, improve thermo-efficiency, reduce the particulate matter in combustion tail gas and NO xdischarge.Also possibility diesel oil substitute, directly as diesel-fuel.
Polymethoxy methylal is solve the defect that dme does the existence of derv fuel oil blend component as the main purpose that Novel clean oil dope is researched and developed.Rich coal resources in China, has strategic importance and good economic worth by coal-based methanol combined diesel oil blend component, is day by day subject to people's attention.
US2449469 disclose a kind of with methylal and paraformaldehyde for raw material, the method using sulfuric acid as the polymethoxy methylal of catalyst preparing n=2 ~ 4, but there is the serious problem of catalytic erosion.
WO2006/045506A1 discloses BASF AG and uses sulfuric acid or trifluoromethanesulfonic acid as catalyzer, with methyl alcohol, methylal, trioxymethylene, paraformaldehyde etc. for raw material, obtains the series product of n=1 ~ 10, there is the problem that catalytic erosion is serious equally.
US5746785 disclose a kind of with 0.1wt% formic acid for catalyzer, with methylal and paraformaldehyde or methyl alcohol and paraformaldehyde for raw material, there is the problem that catalytic erosion is serious in the series product of preparation n=1 ~ 10 equally.
CN101182367A and CN101962318A discloses and adopts acidic ion liquid as catalyzer, is the method that polymethoxy methylal prepared by raw material, there is the problem that catalytic erosion is serious equally by methyl alcohol and trioxymethylene.
CN101665414A discloses a kind of acidic ion liquid that adopts as catalyzer, is the method that polymethoxy methylal prepared by raw material, there is the problem that catalytic erosion is serious equally by methylal and trioxymethylene.
In sum, the catalyzer adopted in conventional art has corrosive shortcoming.
Summary of the invention
Technical problem to be solved by this invention there is catalyzer in conventional art to have corrosive problem, provides a kind of preparation method of new polymethoxy methylal.The method has the free from corrosion advantage of catalyzer.
For solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of preparation method of polymethoxy methylal, with methyl alcohol or dme and formaldehyde or trioxymethylene for raw material, methyl alcohol or dme: formaldehyde or trioxymethylene mol ratio 1:0.1 ~ 10, it is 50 ~ 200 DEG C in temperature of reaction, reaction pressure is under 0.1 ~ 10MPa condition, and reaction raw materials and catalyst exposure generate polymethoxy methylal; Catalyst levels is 0.01 ~ 15% of reaction raw materials weight; Catalyzer wherein used is the ZSM-5 molecular sieve of crystal grain diameter≤5 micron, and described ZSM-5 molecular sieve concentration is that the alkali lye of 0.01 ~ 2 mol/L processes 0.1 ~ 10 hour at 30 ~ 100 DEG C, and wherein alkali lye is 1 ~ 20 with the ratio of the weight of molecular sieve.
In technique scheme, the crystal grain diameter preferable range of described ZSM-5 molecular sieve is 0.1 ~ 5 micron, and more preferably scope is 0.1 ~ 2 micron.The silica alumina ratio preferable range of described ZSM-5 molecular sieve is 10 ~ 500, and more preferably scope is 20 ~ 200.The concentration preferences of alkali lye is 0.1 ~ 1 mol/L, and the treatment temp preferable range of alkali lye is 50 ~ 80 DEG C, and treatment time preferable range is 0.5 ~ 4 hour, and alkali lye is 2 ~ 10 with the ratio preferable range of the weight of molecular sieve.Described alkali lye preferred version is be selected from least one in aqueous sodium hydroxide solution or potassium hydroxide aqueous solution.
Methyl alcohol or dme: formaldehyde or trioxymethylene mol ratio preferable range are 1:0.5 ~ 5.Catalyst levels is the preferable range of reaction raw materials weight is 0.1 ~ 10%.Temperature of reaction preferable range is 70 ~ 150 DEG C, and reaction pressure preferable range is 0.5 ~ 6MPa.
In the inventive method, the molecular sieve after base extraction, before for the preparation of the reaction of polymethoxy methylal, adopts the exchange of known ammonium, dry and roasting technology, obtains catalyzer.
The present invention is by adopting the ZSM-5 molecular sieve through base extraction of crystal grain diameter≤5 micron to be catalyzer, compare conventional ZSM-5 molecular sieve due to ZSM-5 molecular sieve with small crystal grains and there is the higher micropore diffusion speed of larger Extra specific surface area sum, improve catalyzer utilization ratio, strengthen macromole conversion capability, reduce deep reaction, improve selectivity and reduce in coking and deactivation etc. and all show superior performance.In addition, have passed through base extraction again to this ZSM-5 molecular sieve with small crystal grains, due to the molten silicon character of alkali lye, produced again a certain amount of hole in ZSM-5 molecular sieve, these newly-increased holes add catalyzer and hold burnt ability, improve the stability of catalyzer; On the other hand alkali lye can be removed in molecular sieve pore passage amorphous silicon matter or remove the materials such as non-framework silica from framework of molecular sieve, make originally fully to be exposed by amorphous active centre of waiting material to cover in molecular sieve pore passage, play the modification to molecular sieve pore passage, activity of molecular sieve catalysts is increased to some extent, the burnt ability of appearance of catalyzer improves greatly, and activity stability has had very large improvement.So employing the inventive method, under temperature 110 DEG C, pressure 3MPa react 3 hours, n be 3 ~ 8 product can reach 32.4% in products distribution; The most important thing is that catalyzer non-corrosiveness achieves good technique effect.
Further instruction is given to the present invention below by embodiment.
Embodiment
[embodiment 1]
40% silicon sol, sodium metaaluminate, 4-propyl bromide TPABr, sodium-chlor, sodium hydroxide and water are mixed, stirs 20 minutes, in loading reactor, 170 DEG C of dynamic (200 revs/min) crystallization 3 days.Crystallization product chilling, to filter, be washed to pH value be 8, dries 12 hours in 120 DEG C, the obtained former powder of ZSM-5 molecular sieve.In reaction mixture, the mol ratio of each raw material is: SiO 2/ Al 2o 3=80.0, H 2o/SiO 2=50.8, NaCl/SiO 2=0.68, NaOH/SiO 2=0.15, TPABr/SiO 2=0.40.Average crystal grain diameter is 0.5 micron.
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 0.5 micron 2/ Al 2o 3=80), put into the aqueous sodium hydroxide solution that 250 grams of concentration are 0.5 mol/L, 0.5 hour is stirred under reflux in 80 DEG C of constant temperature, filter, with distilled water wash, then exchange three times at 80 DEG C with the aqueous ammonium nitrate solution of 10% mass concentration, aqueous ammonium nitrate solution is 10 with the ratio of the weight of molecular sieve, 120 DEG C of dryings 12 hours, 550 DEG C of roastings 5 hours, obtain catalyst A.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.In autoclave, add 2 grams of catalyzer, 100 grams of methyl alcohol, 100 grams of trioxymethylenes, at 130 DEG C with react 2 hours made pressure be 6MPa by inflated with nitrogen under, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture of acquisition composition is as table 1.
[embodiment 2]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 1 micron 2/ Al 2o 3=40), put into the aqueous sodium hydroxide solution that 100 grams of concentration are 1 mol/L, stir 3 hours in 60 DEG C of constant temperature under reflux, filter, with distilled water wash, with [embodiment 1] ammonium exchange, drying, roasting, shaping, obtain catalyst B.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.In autoclave, add 1.5 grams of catalyzer, 80 grams of dme, 100 grams of trioxymethylenes, at 110 DEG C with react 4 hours made pressure be 4MPa by inflated with nitrogen under, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture of acquisition composition is as table 1.
[embodiment 3]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 0.8 micron 2/ Al 2o 3=100), put into the potassium hydroxide aqueous solution that 500 grams of concentration are 0.2 mol/L, stir 3.5 hours in 50 DEG C of constant temperature under reflux, filter, with distilled water wash, with [embodiment 1] ammonium exchange, drying, roasting, shaping, obtain catalyzer C.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.1.2 grams of catalyzer are added, 50 grams of methyl alcohol, 50 grams of dme in autoclave, 100 grams of trioxymethylenes, 100 DEG C and made pressure be 1MPa by inflated with nitrogen under react 5 hours, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture composition of acquisition is as table 1.
[embodiment 4]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 1.8 microns 2/ Al 2o 3=200), put into the potassium hydroxide aqueous solution that 400 grams of concentration are 0.3 mol/L, stir 2 hours in 70 DEG C of constant temperature under reflux, filter, with distilled water wash, with [embodiment 1] ammonium exchange, drying, roasting, shaping, obtain catalyzer D.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.In autoclave, add 1 gram of catalyzer, 100 grams of dme, 90 grams of formaldehyde, at 80 DEG C with react 5 hours made pressure be 2MPa by inflated with nitrogen under, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture of acquisition composition is as table 1.
[embodiment 5]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 1.2 microns 2/ Al 2o 3=150), put into the aqueous sodium hydroxide solution that 200 grams of concentration are 0.6 mol/L, stir 1.5 hours in 65 DEG C of constant temperature under reflux, filter, with distilled water wash, with [embodiment 1] ammonium exchange, drying, roasting, shaping, obtain catalyzer E.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.In autoclave, add 1 gram of catalyzer, 100 grams of dme, 90 grams of trioxymethylenes, at 90 DEG C with react 5 hours made pressure be 2MPa by inflated with nitrogen under, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture of acquisition composition is as table 1.
[embodiment 6]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 0.2 micron 2/ Al 2o 3=30), put into the aqueous sodium hydroxide solution that 300 grams of concentration are 0.3 mol/L, stir 1.5 hours in 55 DEG C of constant temperature under reflux, filter, with distilled water wash, with [embodiment 1] ammonium exchange, drying, roasting, shaping, obtain catalyzer F.
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit.In autoclave, add 1 gram of catalyzer, 80 grams of dme, 10 grams of methyl alcohol, 90 grams of formaldehyde, at 110 DEG C with react 3 hours made pressure be 3MPa by inflated with nitrogen under, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the mixture of acquisition composition is as table 1.
[comparative example 1]
[embodiment 1] catalyzer, just through base extraction G.
By the condition evaluating catalyst performance of [embodiment 1], reaction result is in table 1.
[comparative example 2]
[embodiment 6] catalyzer, just through base extraction H.
By the condition evaluating catalyst performance of [embodiment 6], reaction result is in table 1.
[comparative example 3]
Get the ZSM-5 molecular sieve (SiO that 50 grams of crystal grain diameters are 10 microns 2/ Al 2o 3=100), with [embodiment 1] ammonium exchange, drying, roasting, shaping, catalyst I is obtained.
By the condition evaluating catalyst performance of [embodiment 1], reaction result is in table 1.
[comparative example 4]
[comparative example 3] catalyzer, base extraction condition, with [embodiment 1], obtains catalyzer J.
By the condition evaluating catalyst performance of [embodiment 1], reaction result is in table 1.
Table 1

Claims (1)

1. a preparation method for polymethoxy methylal, step is as follows:
40% silicon sol, sodium metaaluminate, 4-propyl bromide TPABr, sodium-chlor, sodium hydroxide and water are mixed, stir 20 minutes, load in reactor, crystallization 3 days under the stirring of 170 DEG C and 200 revs/min, crystallization product chilling, to filter, be washed to pH value be 8, dry 12 hours in 120 DEG C, the obtained former powder of ZSM-5 molecular sieve, in reaction mixture, the mol ratio of each raw material is: SiO 2/ Al 2o 3=80.0, H 2o/SiO 2=50.8, NaCl/SiO 2=0.68, NaOH/SiO 2=0.15, TPABr/SiO 2=0.40; Average crystal grain diameter is 0.5 micron;
Getting 50 grams of crystal grain diameters is 0.5 micron, SiO 2/ Al 2o 3the ZSM-5 molecular sieve of=80, put into the aqueous sodium hydroxide solution that 250 grams of concentration are 0.5 mol/L, 0.5 hour is stirred under reflux in 80 DEG C of constant temperature, filter, with distilled water wash, then exchange three times at 80 DEG C with the aqueous ammonium nitrate solution of 10% mass concentration, aqueous ammonium nitrate solution is 10 with the ratio of the weight of molecular sieve, 120 DEG C of dryings 12 hours, 550 DEG C of roastings 5 hours, obtain catalyzer;
The performance evaluation of catalyzer is carried out on 300ml autoclave reaction unit; 2 grams of catalyzer are added in autoclave, 100 grams of methyl alcohol, 100 grams of trioxymethylenes, 130 DEG C and made pressure be 6MPa by inflated with nitrogen under react 2 hours, filtering separation catalyzer and reaction product, through gas chromatographic analysis, the transformation efficiency of trioxymethylene is 80.1%, represent that the PODE that PODE that the PODE of n=1 ~ 2 accounts for 59.1%, n=3 ~ 8 accounts for 32.1%, n>8 accounts for 8.8% with % by weight in product.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101768058A (en) * 2009-01-07 2010-07-07 中国石油化工股份有限公司 Method for preparing polyoxymethylene dimethyl ether
CN102295512A (en) * 2010-06-24 2011-12-28 中国石油化工股份有限公司 Method for preparing ethylene by dehydrating ethanol

Patent Citations (2)

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Publication number Priority date Publication date Assignee Title
CN101768058A (en) * 2009-01-07 2010-07-07 中国石油化工股份有限公司 Method for preparing polyoxymethylene dimethyl ether
CN102295512A (en) * 2010-06-24 2011-12-28 中国石油化工股份有限公司 Method for preparing ethylene by dehydrating ethanol

Non-Patent Citations (1)

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Title
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