CN108658927B - Preparation method and device of 2,4, 6-trioxepane - Google Patents
Preparation method and device of 2,4, 6-trioxepane Download PDFInfo
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- CN108658927B CN108658927B CN201810561158.4A CN201810561158A CN108658927B CN 108658927 B CN108658927 B CN 108658927B CN 201810561158 A CN201810561158 A CN 201810561158A CN 108658927 B CN108658927 B CN 108658927B
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Abstract
The invention relates to the field of chemical industry, in particular to a preparation method of 2,4, 6-trioxepane and a device thereof. A process for preparing 2,4, 6-trioxepane includes such steps as reaction of formaldehyde with methanol to obtain methylal and 2,4, 6-trioxepane, and separating. The preparation method of the 2,4, 6-trioxepane provided by the invention is obtained by reacting formaldehyde and methanol, has the advantages of thorough reaction, high total yield, high product purity, small wastewater pollution, safety, environmental protection and suitability for industrial production.
Description
Technical Field
The invention relates to the field of chemical industry, and particularly relates to a preparation method and a device of 2,4, 6-trioxepane.
Background
2,4, 6-trioxane, also known as paraformaldehyde dimethyl ether, known by the english name 2,4, 6-Trioxaheptane. Colorless clear liquid, slightly smell of ether, medium volatilization speed, slightly water-soluble, boiling point 105 ℃ and freezing point-69 ℃.2, 4, 6-trioxane as an industrial solvent can be applied to paints, inks, coatings, adhesives, and the like; can be used as chemical raw materials for reaction dehydrating agents, methyl etherifying agents, anhydrous formaldehyde reagents, cleaning agents and the like.
The traditional synthesis method of 2,4, 6-trioxepane is prepared by condensing dichloromethyl ether or dibromomethyl ether and methanol in the presence of sodium methoxide, but the method has the disadvantages of high manufacturing cost, large waste water amount, inorganic salt contained in the waste water and high pollution degree. In recent years, the mixture of polyoxymethylene dimethyl ether is synthesized by using methanol or methylal and trioxymethylene or paraformaldehyde in the presence of an acid catalyst at home, and the construction scale is rapidly expanded. In the equilibrium reaction liquid of its catalytic synthesis, it contains a certain quantity of 2,4, 6-trioxane, and during separation, it forms an azeotrope with trioxymethylene in the reaction liquid, and is difficult to separate, and its purity is lower than 92%, and is greatly limited in application.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The first purpose of the invention is to provide a preparation method of 2,4, 6-trioxepane, which is convenient for realizing continuity and automation, has the advantages of thorough reaction of formaldehyde and methanol, higher total yield, higher product purity, small pollution of waste water, safety and environmental protection, and is suitable for industrial production.
The second purpose of the invention is to provide a device for implementing the method, which realizes the continuous and automatic production of the 2,4, 6-trioxane.
In order to achieve the above purpose of the present invention, the following technical solutions are adopted:
a process for preparing 2,4, 6-trioxepane includes such steps as reaction of formaldehyde with methanol to obtain methylal and 2,4, 6-trioxepane, and separating.
The preparation method of the 2,4, 6-trioxepane provided by the invention is obtained by reacting formaldehyde and methanol, has the advantages of thorough reaction, high total yield, high product purity, small wastewater pollution, safety, environmental protection and suitability for industrial production.
Preferably, the formaldehyde is reacted with the methanol under the condition of an acid catalyst.
Preferably, the acid catalyst is a solid acid catalyst.
The application of the solid acid catalyst has good catalytic effect, safety and environmental protection.
Preferably, the acidic catalyst comprises one or more of mordenite, titanium silicalite, sulfonic acid resin, fluorosulfonic acid resin, sodium bisulfate, silica gel particles having sulfuric acid adsorbed thereon. The acid catalysts achieve good effect of catalyzing the reaction of methanol and formaldehyde, and products have no obvious difference.
Further, the temperature of the reaction of the formaldehyde and the methanol is 80-185 ℃.
As in the different embodiments, the formaldehyde and methanol reaction temperature can be 80 degrees, 85 degrees, 86 degrees, 90 degrees, 95 degrees, 100 degrees, 105 degrees, 110 degrees, 120 degrees, 125 degrees, 130 degrees, 135 degrees, 140 degrees, 150 degrees, 160 degrees, 170 degrees, 175 degrees, 180 degrees, 185 degrees.
Preferably, the temperature of the reaction of formaldehyde with methanol is from 85 ℃ to 105 ℃.
Further, rectifying a product obtained by the reaction of the formaldehyde and the methanol, and then further separating to obtain the 2,4, 6-trioxane.
Rectification utilizes the difference of volatility of each component in the mixture to carry out coarse separation of each component, and then further separation is carried out. The mixed gas obtained by crude separation mainly contains 2,4, 6-trioxane, methylal and methanol.
Further, the temperature of the top of the rectification is controlled to be 65-85 ℃, and preferably 70-75 ℃.
Preferably, the methylal and methanol obtained by the separation are returned to the reaction to be used as raw materials to participate in the reaction again.
Namely, the separated methanol can be recycled.
Further, the temperature at the top end of the separation device is controlled at 38 ℃ to 50 ℃, preferably 38 ℃ to 42 ℃.
Preferably, the temperature at the bottom end of the separation apparatus is controlled at 100 ℃ to 110 ℃.
The separation unit is typically a separation column.
The temperature of the top end and the temperature of the lower end of the separation device are controlled, so that the mixed gas is better separated, the 2,4, 6-trioxepane with higher purity is obtained, and the obtained methylal and methanol are returned to the reaction to be used as raw materials to participate in the reaction again.
Preferably, the mass ratio of the formaldehyde to the methanol is 2.5-4:1 based on the liquid amount of the formaldehyde.
As in the different examples, the mass ratio of methanol to formaldehyde may be 1:2.5, 1:3, 1:3.5, 1: 4, etc.
In the preparation method of the 2,4, 6-trioxepane, when formaldehyde reacts with methanol, the formaldehyde is fed in a liquid form, the methanol is fed and gasified, and then the formaldehyde and the methanol are reacted under the condition of a catalyst.
The invention also provides a device for implementing the preparation method of the 2,4, 6-trioxepane, which comprises a synthesis device and a separation device;
the synthesis device sequentially comprises a water vaporization section, a stripping section, a catalytic reaction section and a rectification section from bottom to top.
Preferably, the top end of the synthesis device is connected to the middle of the separation device;
preferably, the top end of the separation device is connected with the catalytic reaction section of the synthesis device.
The preparation method of the 2,4, 6-trioxepane by adopting the device comprises the following specific steps: methanol enters from a methanol inlet at the middle lower part of the synthesis tower, moves upwards after gasification, passes through the middle part of the synthesis tower and is fully covered with granular solid acid catalyst, reacts with liquid formaldehyde which flows to the synthesis tower from the middle upper part of the synthesis tower to generate methylal and 2,4, 6-trioxane, continuously rises with mixed gas phase formed by the methanol, and overflows from the top of the synthesis tower after passing through a rectifying section. And the mixed gas phase enters a separation tower from the middle part, a mixture of methanol and methylal is extracted from the top of the separation tower, qualified 2,4, 6-trioxepane is obtained from the bottom of the tower, the mixture of the methanol and the methylal returns to the middle part of the synthesis tower to enter and continuously participate in the synthesis reaction, and water generated and added in the reaction is discharged from the bottom of the synthesis tower.
Compared with the prior art, the invention has the beneficial effects that:
(1) the preparation method of the 2,4, 6-trioxepane provided by the invention adopts methanol and formaldehyde aqueous solution as raw materials, and the two raw materials are the most basic chemical raw materials, so that the product cost is lower.
(2) The reaction process of the invention does not produce trioxymethylene, so that the 2,4, 6-trioxane is easy to purify, and the product purity is high.
(3) The preparation method of the 2,4, 6-trioxepane provided by the invention has the advantages of high total yield, small wastewater pollution, safety, environmental protection and suitability for industrial production.
(4) The invention applies the solid acid catalyst, has good catalytic effect, and is safe and environment-friendly.
(5) The device provided by the invention realizes continuous and automatic production of 2,4, 6-trioxepane, and has high production effect.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.
Fig. 1 is an apparatus for producing 2,4, 6-trioxane according to the present invention, which is described in example 1.
In the figure:
1-water outlet; 2-a water vaporizer; 3-stripping section; 4-methanol inlet; 5-a catalytic section; 6-returning the mixed liquid to an inlet; 7-formaldehyde inlet; 8-a rectification section; 9-a mixed gas inlet; 10-product outlet; 11-mixed liquid outlet.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Example 1
As shown in fig. 1, the apparatus includes: a synthesizing device and a separating device;
the synthesis device is a synthesis tower, and the separation device is a separation tower;
the synthesis tower comprises: the device comprises a water outlet 1, a water vaporizer 2, a stripping section 3, a methanol inlet 4, a catalytic section 5, a mixed liquid return inlet 6, a formaldehyde inlet 7 and a rectifying section 8;
the separation column comprises: a mixed gas inlet 9, a product outlet 10 and a mixed liquid outlet 11.
Further, the top end of the synthesis device is connected to the middle of the separation device.
Preferably, the top end of the separation device is connected with the catalytic reaction section of the synthesis device.
Example 2
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a catalytic section 5 at the middle part of the synthesis tower, which is full of sulfonic acid resin, and liquid formaldehyde (30 g/minute) fed from a formaldehyde inlet 7 at the middle upper part and flows downwards to the bed layer to react at the temperature of 80-95 ℃ to generate methylal and 2,4, 6-trioxepane, continuously rises, passes through a rectifying section 8 and then overflows from the top of the synthesis tower, and the temperature of the rectifying section 8 is 65-85 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-50 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
The mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at 16g/min and the purity is 99.4 percent (the yield is 95.5 percent).
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 350 mg/L.
Example 3
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthetic tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of mordenite which is fully distributed at a catalytic section 5 at the middle part of the synthetic tower, and reacts with liquid formaldehyde (30 g/minute) which flows downwards from a formaldehyde inlet 7 at the middle upper part of the synthetic tower at the temperature of 90 ℃ to generate methylal and 2,4, 6-trioxane, continuously rises, passes through a rectifying section 8 and overflows from the top of the synthetic tower, and the temperature of the rectifying section 8 is 65-85 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-50 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
The mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at 16g/min and the purity is 99.4 percent (the yield is 95.5 percent).
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 350 mg/L.
Example 4
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a catalyst mixture of mordenite and sulfonic acid resin which is distributed on a catalytic section 5 at the middle part of the synthesis tower, reacts with liquid formaldehyde (25 g/min) which flows downwards from a formaldehyde inlet 7 at the middle upper part of the synthesis tower at the temperature of 90 ℃ to generate methylal and 2,4, 6-trioxane, continuously rises, passes through a rectifying section 8 and then overflows from the top of the synthesis tower, and the temperature of the rectifying section 8 is 65-85 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-50 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
Mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at 15.6g/min and the purity is 99.5 percent.
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 347 mg/L.
Example 5
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a catalysis section 5 at the middle part of the synthesis tower and is full of fluorosulfonic acid resin, and liquid formaldehyde (40 g/minute) fed from a formaldehyde inlet 7 at the middle upper part and flows downwards to the bed layer reacts at the temperature of 90 ℃ to generate methylal and 2,4, 6-trioxane, continues to rise, passes through a rectification section 8 and overflows from the top of the synthesis tower, and the temperature of the rectification section 8 is 65-85 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-50 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
Mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at a rate of 16.2g/min and the purity of 99.3 percent.
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 360 mg/L.
Example 6
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a catalysis section 5 at the middle part of the synthesis tower and is full of fluorosulfonic acid resin, and liquid formaldehyde (30 g/minute) fed from a formaldehyde inlet 7 at the middle upper part and flows downwards to the bed layer reacts at the temperature of 85 ℃ to generate methylal and 2,4, 6-trioxane, continues to rise, passes through a rectification section 8 and overflows from the top of the synthesis tower, and the temperature of the rectification section 8 is 65-70 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-42 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
Mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at a rate of 15g/min and the purity of 93%.
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 365 mg/L.
Example 7
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a catalytic section 5 at the middle part of the synthesis tower and is fully distributed with a titanium silicalite molecular sieve, and liquid formaldehyde (30 g/minute) fed from a formaldehyde inlet 7 at the middle upper part of the synthesis tower and flows downwards to the bed layer reacts at the temperature of 95 ℃ to generate methylal and 2,4, 6-trioxane, continues to rise, passes through a rectifying section 8 and overflows from the top of the synthesis tower, and the temperature of the rectifying section 8 is 65-75 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 38-45 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
The mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at a rate of 16g/min and the purity of 99.5 percent.
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 342 mg/L.
Example 8
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from a methanol inlet 4 at the middle lower part of the synthetic tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of mordenite which is fully distributed in a catalytic section 5 at the middle upper part of the synthetic tower, reacts with liquid formaldehyde (30 g/minute) which flows downwards from a formaldehyde inlet 7 at the middle upper part of the synthetic tower at the temperature of 185 ℃ to generate methylal and 2,4, 6-trioxane, continuously rises, passes through a rectifying section 8 and overflows from the top of the synthetic tower, and the temperature of the rectifying section 8 is 75-85 ℃. The mixed gas phase enters the separation tower from a mixed gas inlet 9 at the middle part of the separation tower, the temperature at the top end of the separation tower is controlled to be 45-50 ℃, and the temperature at the bottom end of the separation tower is controlled to be 100-110 ℃.
The mixed liquid of methanol and methylal is extracted from a mixed liquid outlet 11 at the top of the separation tower, and qualified 2,4, 6-trioxane is continuously obtained from a product outlet 10 at the bottom of the separation tower at a rate of 16g/min and the purity of 99.1 percent.
The mixture of methanol and methylal returns to the middle part of the synthesis tower, and the mixed liquid returns to the inlet 6 to continuously participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a water vaporizer 2, methanol and formaldehyde in water are vaporized by controlling the temperature of more than 100 ℃, the vaporized methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water generated by the reaction with the added formaldehyde is discharged out of the system from a water outlet 1 at the bottom, and the COD is 343 mg/L.
Comparative example 1
The preparation method of 2,4, 6-trioxepane is carried out by adopting the device provided by the embodiment 1, and comprises the following specific steps:
methanol enters from the middle lower part 4 of the synthesis tower at the speed of 10g per minute, moves upwards after gasification, passes through a bed layer of a middle part 5 of the synthesis tower and is fully covered with a solid acid catalyst, reacts with liquid formaldehyde (30 g/min) fed from the middle upper part 7 and flowing downwards to the middle lower part at the temperature of 80-85 ℃ to generate methylal, the methylal and the methanol form mixed gas to continuously rise, the mixed gas passes through a rectifying section 8, the temperature is controlled to be 43-48 ℃ and overflows from the top of the synthesis tower, the mixed gas phase enters a separation tower from the middle part 9 of the separation tower, mixed liquid 11 of the methanol and the methylal is collected from the top of the separation tower, and 2,4, 6-trioxane can hardly be obtained from the bottom of the tower 10.
The mixture of methanol and methylal returns to the middle part 6 of the synthesis tower to enter and continue to participate in the synthesis reaction.
The lower part of the synthesis tower is provided with a vaporizer 2, methanol and formaldehyde in water are evaporated by controlling the temperature of more than 100 ℃, the evaporated methanol and formaldehyde are sent to a reaction area through a stripping section 3, the water produced along with the addition of the formaldehyde and the reaction is discharged out of the system from the bottom 1, however, under the condition of no formation of 2,4, 6-trioxane, the circulation volume of the system is increased, the feeding cannot be continued, and the experiment is finished after 30 minutes of feeding.
Experiments prove that if the process conditions of the preparation method of the 2,4, 6-trioxepane provided by the invention cannot be met, the 2,4, 6-trioxepane cannot be synthesized.
Comparative example 2
The preparation method of the 2,4, 6-trioxepane comprises the following steps:
adding 378g of methanol solution containing 30% of sodium methoxide and 115g of dichloromethyl ether into a pressure kettle, starting stirring, slowly heating, finally heating to 85 ℃, stirring for reaction for 2 hours, cooling to room temperature, adding glacial acetic acid to adjust the pH value of 9 after discharging, filtering out 115g of sodium chloride, adding clear liquid into a distillation flask, fractionating through a thorn-type fractionating column, collecting fractions with the gas phase of 104-class and the temperature of 106 ℃, obtaining 85.5g of 2,4, 6-trioxepane with the purity of 99.2% (the molar yield is 80.66%).
Comparative example 3
The preparation method of the 2,4, 6-trioxepane comprises the following steps:
putting 400g of methylal, 100g of trioxymethylene and 50g of acid catalyst into a pressure kettle, stirring and heating to 130 ℃, stirring and reacting for 5 hours, cooling to room temperature, filtering out the catalyst, collecting 198g (with the purity of 94%) of methylal which is a 39-42 ℃ fraction by using a thorn-type fractionating column and normal pressure distillation, collecting 198g of methylal which is a 39-42 ℃ fraction by normal pressure distillation, collecting 97g of 2,4, 6-trioxepane which is a 99-104 ℃ fraction by normal pressure distillation, containing 89% of 2,4, 6-trioxepane, 9.5% of trioxymethylene and the rest 1.5 by normal pressure distillation, and collecting 130g of DMM (3-8) which is a 88-156 ℃ fraction by vacuum distillation; 45g of residue; 30g are lost. Then 97g of the obtained mixture of the 2,4, 6-trioxepane and trioxymethylene is added into the flask again, and is separated by a high-efficiency separation column, only the 2,4, 6-trioxepane containing 7.3% of trioxymethylene can be obtained, and the purity of the 2,4, 6-trioxepane is below 92%.
While particular embodiments of the present invention have been illustrated and described, it would be obvious that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
Claims (4)
1. A preparation method of 2,4, 6-trioxepane is characterized in that formaldehyde reacts with methanol to generate methylal and 2,4, 6-trioxepane, and the methylal and the 2,4, 6-trioxepane are separated to obtain the trioxepane;
the mass ratio of the formaldehyde to the methanol is 2.5-4:1 in terms of liquid amount;
the reaction temperature of the formaldehyde and the methanol is 85-105 ℃;
the device of the preparation method of the 2,4, 6-trioxepane comprises a synthesis device and a separation device;
the synthesis device sequentially comprises a water vaporization section, a stripping section, a catalytic reaction section and a rectification section from bottom to top;
the temperature of the top end of the separation device is controlled to be 38-50 ℃; the temperature of the bottom end of the separation device is controlled to be 100-110 ℃;
the preparation method of the 2,4, 6-trioxepane specifically comprises the following steps: methanol enters from a methanol inlet at the middle lower part of the synthesis tower, moves upwards after gasification, passes through the middle part of the synthesis tower and is fully covered with granular solid acid catalyst, reacts with liquid formaldehyde which flows to the synthesis tower from the middle upper part of the synthesis tower to generate methylal and 2,4, 6-trioxane, continuously rises with mixed gas phase formed by the methanol, and overflows from the top of the synthesis tower after passing through a rectifying section; and the mixed gas phase enters a separation tower from the middle part, a mixture of methanol and methylal is extracted from the top of the separation tower, qualified 2,4, 6-trioxepane is obtained from the bottom of the tower, the mixture of the methanol and the methylal returns to the middle part of the synthesis tower to enter and continuously participate in the synthesis reaction, and water generated and added in the reaction is discharged from the bottom of the synthesis tower.
2. The method of claim 1, wherein the acidic catalyst comprises one or more of mordenite, titanium silicalite, sulfonic acid resin, fluorosulfonic acid resin, sodium bisulfate, silica gel particles having sulfuric acid adsorbed thereon.
3. A process for the preparation of 2,4, 6-trioxane according to claim 1, characterized in that the temperature at the top of the rectification is controlled between 65 ℃ and 85 ℃.
4. The method of preparing 2,4, 6-trioxane according to claim 1, wherein a top end of the synthesizing device is connected to a middle portion of the separating device.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6392102B1 (en) * | 1998-11-12 | 2002-05-21 | Bp Corporation North America Inc. | Preparation of polyoxymethylene dimethyl ethers by catalytic conversion of formaldehyde formed by oxidation of dimethyl ether |
| CN101198630A (en) * | 2005-06-15 | 2008-06-11 | 巴斯福股份公司 | Method for producing polyoxymethylene dimethyl ethers from methanol and formaldehyde |
| CN107522602A (en) * | 2017-09-08 | 2017-12-29 | 青岛迈特达新材料有限公司 | A kind of technique and system for preparing DMM2 |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6392102B1 (en) * | 1998-11-12 | 2002-05-21 | Bp Corporation North America Inc. | Preparation of polyoxymethylene dimethyl ethers by catalytic conversion of formaldehyde formed by oxidation of dimethyl ether |
| CN101198630A (en) * | 2005-06-15 | 2008-06-11 | 巴斯福股份公司 | Method for producing polyoxymethylene dimethyl ethers from methanol and formaldehyde |
| CN107522602A (en) * | 2017-09-08 | 2017-12-29 | 青岛迈特达新材料有限公司 | A kind of technique and system for preparing DMM2 |
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