CN106966879B - Equipment and process for producing acetyl n-propanol by kettle type continuous hydrogenation - Google Patents
Equipment and process for producing acetyl n-propanol by kettle type continuous hydrogenation Download PDFInfo
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- CN106966879B CN106966879B CN201710090040.3A CN201710090040A CN106966879B CN 106966879 B CN106966879 B CN 106966879B CN 201710090040 A CN201710090040 A CN 201710090040A CN 106966879 B CN106966879 B CN 106966879B
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Abstract
The invention discloses kettle type equipment for producing acetyl-n-propanol by continuous hydrogenation, which comprises two 2-methylfuran metering tanks, an organic phase metering pump, two aqueous phase mixing kettles, two aqueous phase metering pumps, a reaction kettle, a condenser, a gas-liquid separator and a filter, wherein the 2-methylfuran metering tank is connected to the organic phase metering pump, the two aqueous phase mixing kettles are connected to the same aqueous phase metering pump, the organic phase metering pump and the aqueous phase metering pump are connected to a feed inlet of the reaction kettle, a discharge outlet above the reaction kettle is connected to the gas-liquid separator, the condenser is arranged above the gas-liquid separator, and the two filters are connected in parallel behind the gas-liquid separator. In the invention, the continuous kettle type liquid phase continuous hydrogenation method is used for reaction, the treatment links before and after each kettle are omitted, the time is saved, the efficiency is improved, the hydrogen in the reaction can be recycled, the hydrogen loss is reduced, and the pollution to the atmosphere is reduced.
Description
Technical Field
The invention relates to the field of chemical industry, in particular to equipment and a process for producing acetyl-n-propanol by kettle type continuous hydrogenation.
Background
Acetyl n-propanol is an important medical intermediate, is a main intermediate of anti-AIDS drugs efavirenz and irinotecan, is used for antimalarial drugs chloroquine phosphate, can also be used for producing vitamin B1 and the like, and is also an intermediate of bactericide cyprodinil and cyproconazole.
At present, the production process of the acetyl-n-propanol mainly comprises 3 types: the fine organic chemical raw materials and the intermediate handbook (Xuke-master edition) relate to two types:
the method has the advantages that the method is a 2-methyl furan palladium chloride catalytic hydrogenation method, the reaction period is long (about 120 hours per batch), and the industrial efficiency is low;
the gamma-butyrolactone method has high requirements on reaction temperature (350-;
thirdly, the method for producing the acetyl-n-propanol by intermittently catalyzing and hydrogenating the 2-methylfuran in the Chinese patent CN102140058A by using a palladium-carbon catalyst has the advantages of simple operation, convenient control and mild reaction conditions, and is suitable for industrial production.
Disclosure of Invention
The technical problem to be solved by the invention is to provide equipment and a process for producing acetyl-n-propanol by a kettle type continuous hydrogenation mode, so as to solve the defects in the background technology.
The technical problem solved by the invention is realized by adopting the following technical scheme: the utility model provides an equipment of cauldron formula continuous hydrogenation production acetyl-n-propanol, includes 2-methylfuran metering tank, organic phase measuring pump, aqueous phase blending cauldron, aqueous phase measuring pump, reation kettle, condenser, vapour and liquid separator and filter, 2-methylfuran metering tank connects on the organic phase measuring pump, the aqueous phase blending cauldron has two, two the aqueous phase blending cauldron is all connected on same aqueous phase measuring pump, organic phase measuring pump and aqueous phase measuring pump are all connected on reation kettle's the feed inlet, connecting on the discharge gate of reation kettle top vapour and liquid separator's top is equipped with the condenser, vapour and liquid separator is still parallelly connected two at the back the filter.
A process for producing acetyl-n-propanol by kettle-type continuous hydrogenation,
1) 1440kg of 2-methylfuran in a 2-methylfuran measuring tank, 360kg of water in one water phase mixing kettle, 5kg of 31% hydrochloric acid and 4kg of palladium-carbon catalyst are added into a 3m cultivation reaction kettle, nitrogen and hydrogen are used for replacing for three times respectively, the reaction temperature in the reaction kettle (205) is controlled to be 25-30 ℃, the hydrogen pressure in the kettle is controlled to be 0.28MPa, and the reaction is carried out for 9 hours;
2) pumping the catalyst uniformly mixed in the other water phase mixing kettle into a reaction kettle by 40kg/h acid water and 160kg/h 2-methylfuran through a water phase metering pump and an organic phase metering pump respectively, continuously introducing hydrogen for reaction, opening a feeding pump, then opening a discharging valve, pressing reaction liquid in the reaction kettle into a gas-liquid separator through a filter, automatically opening a bottom valve after filtrate in the gas-liquid separator reaches a certain liquid level, feeding the filtrate into a neutralization kettle through the filter, and performing neutralization and distillation to obtain qualified acetyl n-propanol;
3) and hydrogen on the upper part of the gas-liquid separator passes through a condenser and enters a hydrogen compressor through a hydrogen return pipe for recycling.
In the invention, further, a hydrogen inlet pipe is arranged at the top of the reaction kettle, and the reaction kettle is wrapped with an ice water jacket.
In the invention, further, the hydrogen gas at the upper part of the gas-liquid separator passes through a condenser and enters a hydrogen gas compressor through a hydrogen return pipe for recycling.
In the invention, furthermore, the feeding quantity of the reaction kettle in the kettle type continuous hydrogenation part is controlled by a metering pump, the discharging quantity is controlled by the liquid level change in a gas-liquid separator in combination with the opening degree of a discharging valve, the hydrogen returning gas is automatically controlled by the linkage of the pressure in the gas-liquid separator and an exhaust valve, the exhaust pressure range is kept between 0.05 and 0.20MPa, and the feeding quantity and the discharging quantity are kept in a balanced state.
The invention has the beneficial effects that: the continuous kettle type liquid phase continuous hydrogenation method is used for reaction, processing links before and after each kettle are omitted, time is greatly saved, efficiency is improved, hydrogen in the reaction can be recycled, hydrogen loss is greatly reduced, and pollution to atmosphere caused by discharging hydrogen waste gas into air is reduced.
Drawings
FIG. 1 is a schematic view of the structure of a kettle-type continuous hydrogenation part in the present invention;
FIG. 2 is a schematic structural view of a reaction vessel 205 according to the present invention;
FIG. 3 is a top view of a reaction vessel 205 of the present invention;
FIG. 4 is a schematic diagram of a filter structure in the reaction vessel 205 according to the present invention;
FIG. 5 is a process flow diagram of the kettle-type continuous hydrogenation section of the present invention;
in the figure:
in fig. 1: a 2-methylfuran metering tank 201, an organic phase metering pump 202, an aqueous phase mixing kettle 203, an aqueous phase metering pump 204, a reaction kettle 205, a condenser 206, a gas-liquid separator 207 and a filter 208;
in fig. 2 and 3: hydrogen inlet pipe 1, feed pipe 2, stirring rake 3, discharging pipe 4, filter 5, hydrogen distributor 6, frozen water jacket 7.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.
Example (b): the device for producing acetyl-n-propanol by kettle-type continuous hydrogenation comprises a 2-methylfuran metering tank 201, an organic phase metering pump 202, an aqueous phase mixing tank 203, an aqueous phase metering pump 204, a reaction kettle 205, a condenser 206, a gas-liquid separator 207 and a filter 208, wherein the 2-methylfuran metering tank 201 is connected to the organic phase metering pump 202, the number of the aqueous phase mixing tanks 203 is two, the two aqueous phase mixing tanks 203 are connected to the same aqueous phase metering pump 204, the organic phase metering pump 202 and the aqueous phase metering pump 204 are connected to a feed inlet of the reaction kettle 205, a discharge port above the reaction kettle 205 is connected to the gas-liquid separator 207, the condenser 206 is arranged above the gas-liquid separator 207, and the back of the gas-liquid separator 207 is connected to the two filters 208 in parallel; the top of the reaction kettle 205 is also provided with a hydrogen inlet pipe, the reaction kettle 205 is also wrapped with an ice water jacket, and hydrogen on the upper part of the gas-liquid separator 207 passes through a condenser and enters a hydrogen compressor through a hydrogen return pipe for recycling.
The working process is as follows:
as shown in fig. 5, the 2-methylfuran and the acid water uniformly mixed in the 2-methylfuran metering tank 201 and the aqueous phase mixing kettle 203 respectively pass through the organic phase metering pump 202 and the aqueous phase mixing kettle 203, and are mixed and enter the reaction kettle 205 before entering the reaction kettle according to a certain proportion, under the condition of fully and uniformly mixing in the reaction kettle 205, hydrogen is introduced into the reaction kettle 205 through a hydrogen introducing pipe for hydrogen introducing reaction, the reaction temperature is controlled by an ice water jacket on the reaction kettle 205, the reaction liquid is pressed into the gas-liquid separator 207 through a filter in the reaction kettle 205, the catalyst is left in the reaction kettle 205 by the filter in the reaction kettle 205 to continuously play a role of catalysis, the feed liquid discharged by the filter is in a gas-liquid mixing form, after the feed liquid enters the gas-liquid separator 207, the liquid part is discharged from the bottom of the gas-liquid separator 207, enters a neutralization kettle through two filters 208 and is subjected to subsequent treatment; the hydrogen gas at the upper part of the gas-liquid separator 207 passes through the condenser 206, the residual liquid in the reaction liquid is further cooled and remained in the liquid phase, and the non-condensable hydrogen gas enters a hydrogen gas compressor through a hydrogen return pipe for recycling. Wherein the feeding amount is controlled by a metering pump, and the discharging amount is controlled by the liquid level in the gas-liquid separator 207, so that the feeding amount and the discharging amount are kept in a balanced state.
As shown in fig. 2, 3 and 4, the reaction vessel 205 has a structure including a hydrogen inlet pipe 1, a feed pipe 2, a stirring paddle 3, a discharge pipe 4, a filter 5, a hydrogen distributor 6 and an ice water jacket 7.
Its advantage does:
1. one set of mixing kettle is formed by combining two kettles, and the two kettles are switched back and forth, so that continuous material feeding can be ensured, one set of mixing kettle can be used for 5 reaction kettles for 12 hours, the capacity of a single kettle reaches 1.2 t/day which is far greater than about 600 kg/day of a batch reaction kettle, and the capacity efficiency is greatly improved;
2. all material transferring processes use pumps to transfer materials, so that a barreled material transferring mode of intermittent feeding is avoided, the safety is improved, the operation flow is simplified, and the operation difficulty is reduced;
3. the continuous feeding and discharging operation saves the processes of manual material transfer in the middle and material transfer to the kettle, nitrogen and hydrogen replacement and the like in each batch, simplifies the operation flow, greatly saves the operation time, and reduces the pollution to the atmosphere caused by the discharge of nitrogen and hydrogen waste gas into the air.
4. The hydrogen returning device is added, so that the use amount of hydrogen is greatly saved, and the pollution to the atmosphere caused by the exhaust of hydrogen waste gas into the air is reduced.
A process for producing acetyl-n-propanol by kettle-type continuous hydrogenation,
1) 1440kg of 2-methylfuran in a 2-methylfuran metering tank 201, 360kg of water in one of the aqueous phase mixing kettles 203, 5kg of 31% hydrochloric acid and 4kg of palladium-carbon catalyst are added into a 3 m-silvestris reaction kettle 205, nitrogen and hydrogen are used for replacing for three times respectively, the reaction temperature in the reaction kettle 205 is controlled to be 25-30 ℃, the hydrogen pressure in the kettle is controlled to be 0.28MPa, after 9 hours of reaction,
2) the catalyst after being mixed in the other water phase mixing kettle 203 is respectively pumped into a reaction kettle 205 by 40kg/h acid water and 160kg/h 2-methylfuran through a water phase metering pump 204 and an organic phase metering pump 202 for continuous hydrogen reaction, a discharge valve is opened after a feed pump is started, reaction liquid is pressed into a gas-liquid separator 207 through a filter in the reaction kettle 205, a bottom valve is automatically opened after the filtrate in the gas-liquid separator 207 reaches a certain liquid level, the filtrate enters a neutralization kettle through a filter 208, and qualified acetyl-n-propanol is obtained through neutralization and distillation operations,
3) and hydrogen on the upper part of the gas-liquid separator passes through a condenser and enters a hydrogen compressor through a hydrogen return pipe for recycling.
The feeding amount of the reaction kettle 205 in the kettle type continuous hydrogenation part is controlled by a metering pump, the discharging amount is controlled by the combination of the liquid level change in the gas-liquid separator 207 and the opening degree of the discharging valve, the hydrogen return gas is automatically controlled by the linkage of the pressure in the gas-liquid separator 207 and the exhaust valve, the exhaust pressure range is kept between 0.05 and 0.20MPa, and the feeding amount and the discharging amount are kept in a balanced state.
While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be understood by those skilled in the art that the invention is not limited by the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.
Claims (4)
1. A process for producing acetyl n-propanol by kettle type continuous hydrogenation is characterized in that:
1) 1440kg of 2-methylfuran in a 2-methylfuran metering tank (201), 360kg of water in one water phase mixing kettle (203), 5kg of 31% hydrochloric acid and 4kg of palladium-carbon catalyst are added into a 3m high-speed growing reaction kettle (205), nitrogen and hydrogen are used for replacing for three times respectively, the reaction temperature in the reaction kettle (205) is controlled to be 25-30 ℃, the hydrogen pressure in the kettle is controlled to be 0.28MPa, and the reaction is carried out for 9 hours;
2) pumping the acid water uniformly mixed in the other water-phase mixing kettle (203) into a reaction kettle (205) at the speed of 40kg/h and the 2-methylfuran in a 2-methylfuran metering tank (201) at the speed of 160kg/h through a water-phase metering pump (204) and an organic-phase metering pump (202) respectively to continue hydrogen introduction reaction, opening a discharge valve after a feed pump is started, pressing reaction liquid into a gas-liquid separator (207) through a filter in the reaction kettle (205), automatically opening a bottom valve after the filtrate in the gas-liquid separator (207) reaches a certain liquid level, introducing the reaction liquid into a neutralization kettle through a filter (208), and performing neutralization and distillation operations to obtain qualified acetyl-n-propanol;
3) and hydrogen on the upper part of the gas-liquid separator passes through a condenser and enters a hydrogen compressor through a hydrogen return pipe for recycling.
2. The process for producing acetyl-n-propanol by kettle-type continuous hydrogenation according to claim 1, which is characterized in that: the feeding amount of a reaction kettle (205) in the kettle type continuous hydrogenation part is controlled by a metering pump, the discharging amount is controlled by the liquid level change in a gas-liquid separator (207) in combination with the opening degree of a discharging valve, the hydrogen return gas is automatically controlled by the linkage of the pressure in the gas-liquid separator (207) and an exhaust valve, the exhaust pressure range is kept between 0.05 and 0.20MPa, and the feeding amount and the discharging amount are kept in a balanced state.
3. The device for producing the acetyl n-propanol by the kettle type continuous hydrogenation comprises a 2-methylfuran metering tank (201), an organic phase metering pump (202), an aqueous phase mixing kettle (203), an aqueous phase metering pump (204), a reaction kettle (205), a condenser (206), a gas-liquid separator (207) and a filter (208), and is characterized in that: the device comprises an organic phase metering pump (202), an aqueous phase mixing tank (201), an aqueous phase metering pump (203), a gas-liquid separator (207), a condenser (206), a gas-liquid separator (207), a filter (208), a hydrogen inlet pipe, an ice water jacket, and a filter, wherein the 2-methylfuran metering tank (201) is connected to the organic phase metering pump (202), the aqueous phase mixing tank (203) is provided with two, the aqueous phase mixing tank (203) is connected to the same aqueous phase metering pump (204), the feeding is switched with each other, the organic phase metering pump (202) and the aqueous phase metering pump (204) are connected to a feeding port of the reaction kettle (205), a discharging port above the reaction kettle (205) is connected to the gas-liquid separator (207), the condenser (206) is arranged above the gas-liquid separator (207), the two filters (208) are connected in parallel to the back of the gas-liquid separator.
4. The apparatus for producing n-propyl acetyl alcohol through kettle-type continuous hydrogenation according to claim 3, which is characterized in that: and hydrogen at the upper part of the gas-liquid separator (207) passes through a condenser and enters a hydrogen compressor through a hydrogen return pipe for recycling.
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| CN110052049B (en) * | 2019-05-24 | 2024-02-09 | 山东一诺生物质材料有限公司 | Equipment and method for producing acetyl n-propanol by continuous hydrogenation of 2-methyl furan |
| CN110862310B (en) * | 2019-12-05 | 2022-12-27 | 上海生农生化制品股份有限公司 | Synthesis method of cyclopropyl methyl ketone |
| CN112028096A (en) * | 2020-10-12 | 2020-12-04 | 山西复晟铝业有限公司 | Connecting system for reducing liquid content of seed crystal filter cake and control method |
| CN113233965A (en) * | 2021-05-06 | 2021-08-10 | 江苏清泉化学股份有限公司 | Synthesis method of acetyl n-propanol |
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| CN106187686A (en) * | 2016-07-07 | 2016-12-07 | 江苏凯特新材料科技有限公司 | A kind of continuous catalytic hydrogenation prepares process and the response system of 1,2 propylene glycol |
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| WO2012004808A1 (en) * | 2010-07-08 | 2012-01-12 | Indian Oil Corporation Ltd. | Apparatus and process for gas to liquid (gtl) conversion |
| CN102140058B (en) * | 2011-02-26 | 2013-08-21 | 安徽绩溪县徽煌化工有限公司 | Method for preparing gamma-acetyl propanol |
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| CN106187686A (en) * | 2016-07-07 | 2016-12-07 | 江苏凯特新材料科技有限公司 | A kind of continuous catalytic hydrogenation prepares process and the response system of 1,2 propylene glycol |
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