CN116947786A - Separation method for preparing epoxypropane by direct oxidation method - Google Patents
Separation method for preparing epoxypropane by direct oxidation method Download PDFInfo
- Publication number
- CN116947786A CN116947786A CN202210412694.4A CN202210412694A CN116947786A CN 116947786 A CN116947786 A CN 116947786A CN 202210412694 A CN202210412694 A CN 202210412694A CN 116947786 A CN116947786 A CN 116947786A
- Authority
- CN
- China
- Prior art keywords
- propylene
- separation
- tower
- column
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000926 separation method Methods 0.000 title claims abstract description 157
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000007254 oxidation reaction Methods 0.000 title claims abstract description 32
- 230000003647 oxidation Effects 0.000 title claims abstract description 30
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 270
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims abstract description 117
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims abstract description 116
- 238000011084 recovery Methods 0.000 claims abstract description 32
- 238000010521 absorption reaction Methods 0.000 claims abstract description 27
- 239000006096 absorbing agent Substances 0.000 claims abstract description 12
- 239000007789 gas Substances 0.000 claims description 35
- 230000008569 process Effects 0.000 claims description 13
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 239000011261 inert gas Substances 0.000 claims description 6
- 238000007086 side reaction Methods 0.000 abstract description 9
- 238000005265 energy consumption Methods 0.000 abstract description 6
- 230000009286 beneficial effect Effects 0.000 abstract description 4
- 238000002360 preparation method Methods 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 31
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 238000006735 epoxidation reaction Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- 238000007670 refining Methods 0.000 description 5
- XENVCRGQTABGKY-ZHACJKMWSA-N chlorohydrin Chemical compound CC#CC#CC#CC#C\C=C\C(Cl)CO XENVCRGQTABGKY-ZHACJKMWSA-N 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 241000208125 Nicotiana Species 0.000 description 1
- 235000002637 Nicotiana tabacum Nutrition 0.000 description 1
- UGACIEPFGXRWCH-UHFFFAOYSA-N [Si].[Ti] Chemical compound [Si].[Ti] UGACIEPFGXRWCH-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D301/00—Preparation of oxiranes
- C07D301/32—Separation; Purification
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/005—Processes comprising at least two steps in series
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/04—Purification; Separation; Use of additives by distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D303/00—Compounds containing three-membered rings having one oxygen atom as the only ring hetero atom
- C07D303/02—Compounds containing oxirane rings
- C07D303/04—Compounds containing oxirane rings containing only hydrogen and carbon atoms in addition to the ring oxygen atoms
Abstract
The invention provides a separation method for preparing epoxypropane by a direct oxidation method, and relates to the field of epoxypropane preparation. The separation method for preparing propylene oxide by using the direct oxidation method comprises the steps of feeding product gas sent out from a reactor into a high-pressure propylene rough separation tower to realize rough separation of propylene and propylene oxide in the high-pressure propylene rough separation tower; sending the tower bottom product of the high-pressure propylene crude separation tower to a low-pressure PO crude separation tower to realize separation of PO and methanol; feeding crude PO and propylene gas withdrawn from the top of the low pressure PO crude separation column to a PO absorber to separate PO from propylene; pressurizing the gas at the top of the PO absorption tower by a compressor, and then sending the gas to a propylene separation tower; withdrawing PO from said PO absorber and passing it to a PO product column; methanol is extracted from the bottom of the low-pressure PO crude separation tower and sent to a methanol recovery tower. The invention realizes the recovery of most propylene through the high-low pressure rough separation tower, reduces the occurrence of side reaction and is beneficial to saving energy consumption.
Description
Technical Field
The invention relates to the field of preparation of propylene oxide, in particular to a separation method for preparing propylene oxide by a direct oxidation method.
Background
Propylene oxide is the 2 nd large propylene derivative and has wide application in the industries of automobiles, buildings, foods, tobacco, medicines and the like. The synthesis process of propylene oxide mainly comprises a chlorohydrin method, an indirect oxidation method and a hydrogen peroxide direct oxidation method, and at present, the production method of propylene oxide mainly comprises a chlorohydrin method and a co-oxidation method. The three wastes discharge amount of the chlorohydrin method is large, the environmental pollution is serious, and the process route of the chlorohydrin method faces the risk of elimination and upgrading. The co-oxidation method has high investment cost, long process flow and high requirement on raw material purity, and needs to balance a large amount of co-products, and the development prospect depends on the market raw material supply and the sales condition of the co-products. The process for preparing the propylene oxide by adopting the hydrogen peroxide direct oxidation method has the characteristics of mild condition, simple process, single product, environmental protection, high atomic economic utilization rate of 76.9 percent and the like, and is the development trend of the propylene oxide synthesis technology. The epoxypropane has active chemical property, is easy to generate side reaction with methanol and water, can select the thought of a subsequent separation unit to reduce the side reaction, and has the advantages of epoxypropane separation, byproduct reduction and high energy consumption.
Disclosure of Invention
The object of the present invention includes, for example, providing a separation process for producing propylene oxide by a direct oxidation process, which achieves recovery of most of propylene by a high-low pressure crude separation column, reduces occurrence of side reactions, and contributes to energy saving.
Embodiments of the invention may be implemented as follows:
the embodiment of the invention provides a separation method for preparing propylene oxide by a direct oxidation method, which comprises the following steps:
feeding the product gas from the reactor to a high pressure propylene crude separation column 10 to effect crude separation of propylene and propylene oxide in the high pressure propylene crude separation column;
sending the bottom product of the high-pressure propylene crude separation column 10 to a low-pressure PO crude separation column 20 to realize separation of PO and methanol;
feeding the crude PO and propylene gas withdrawn from the top of the low pressure PO crude separation column 20 to a PO absorption column 30 to separate PO and propylene;
the gas at the top of the PO absorption column 30 is pressurized by a compressor 31 and then sent to a propylene separation column 40;
withdrawing PO from the PO absorber 30 and passing it to a PO product column;
methanol is extracted from the bottom of the low-pressure PO crude separation tower and sent to a methanol recovery tower.
Further, in an alternative embodiment, the inlet of the high pressure propylene crude separation column is connected to the product gas reactor, the upper outlet of the high pressure propylene crude separation column is connected to the propylene separation column, and the lower outlet is connected to the low pressure PO crude separation column.
Further, in an alternative embodiment, the upper outlet of the low pressure PO crude separation column is connected to a PO absorber and the lower outlet is connected to a PO absorber.
Further, in an alternative embodiment, an upper outlet of the PO absorber is connected to a propylene compressor, the propylene compressor is connected to the propylene separation column, and a lower outlet of the PO absorber is connected to the PO product column.
Further, in an alternative embodiment, a lower outlet of the PO product column is connected to the methanol recovery column.
Further, in an alternative embodiment, the methanol recovery column includes a first methanol column and a second methanol column.
Further, in an alternative embodiment, the low-pressure PO crude separation column and the PO product column are connected to the first methanol column, and an inlet and an outlet of the first methanol column are correspondingly connected to an inlet and an outlet of the second methanol column.
Further, in an alternative embodiment, the first methanol column and the second methanol column are each coupled to a methanol removal reactor.
Further, in an alternative embodiment, the upper outlet of the high pressure propylene crude separation column is connected to a tail gas absorber.
Further, in an alternative embodiment, inert gas is introduced into the bottom of the high-pressure propylene crude separation tower.
Further, in an alternative embodiment, the high pressure propylene crude separation column is provided with an intermediate reboiler that is capable of increasing propylene production.
The separation method for preparing propylene oxide by using the direct oxidation method provided by the invention has the following beneficial effects: the product gas sent from the reactor is sent to a high-pressure separation tower, propylene and epoxypropane are roughly separated in the high-pressure separation tower, the tower bottom product is sent to a low-pressure separation tower to realize the separation of PO and methanol, the crude PO and propylene gas extracted from the tower top of the low-pressure separation tower are sent to a PO rough separation tower, PO and propylene are separated, methanol at the bottom of the low-pressure separation tower is further recovered by a methanol recovery tower, the tower top gas of the PO rough separation tower is sent to a propylene separation tower after being pressurized by a compressor, PO is extracted from the PO rough separation tower to a PO refining tower, and methanol extracted from the tower bottom of the PO rough separation tower is sent to a methanol recovery tower. The method provided by the invention is different from the conventional PO separation process, realizes recovery of most of propylene through the high-low pressure rough separation tower, reduces side reaction, and is beneficial to saving energy consumption.
Drawings
In order to more clearly illustrate the technical solution of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described. It is appreciated that the following drawings depict only certain embodiments of the invention and are therefore not to be considered limiting of its scope. Other relevant drawings may be made by those of ordinary skill in the art without undue burden from these drawings.
FIG. 1 is a schematic view of a first embodiment of a separation process for producing propylene oxide by direct oxidation according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a second embodiment of a separation process for producing propylene oxide by direct oxidation according to an embodiment of the present invention;
fig. 3 is a schematic view showing a third embodiment of a separation method for preparing propylene oxide by a direct oxidation method according to an embodiment of the present invention.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
It should be noted that the features of the embodiments of the present invention may be combined with each other without conflict.
The following describes specific embodiments of the present invention in detail with reference to the drawings.
Referring to fig. 1, the present embodiment provides a separation method for preparing propylene oxide by a direct oxidation method, which realizes recovery of most propylene by a high-low pressure rough separation tower, reduces occurrence of side reaction, and helps to save energy consumption.
The invention relates to a separation method for producing propylene oxide by a direct oxidation method, wherein the production procedures of the direct oxidation method mainly comprise epoxidation reaction, product rectification, propylene circulation, methanol circulation, wastewater treatment and the like. The main process route is that propylene and hydrogen peroxide flow through an epoxidation reactor under the condition that methanol is used as a solvent, and under the action of a titanium silicon catalyst, epoxidation reaction is directly carried out to generate propylene oxide, water and a small amount of byproducts, and a reaction product flow flows to a downstream unit. And (3) recycling excessive propylene in the reaction raw materials by utilizing rectification operation, and returning the propylene to the epoxidation reactor to be used as the raw materials for recycling. And (3) feeding the crude propylene oxide generated in the epoxidation reactor into a product rectifying unit to finally obtain a propylene oxide product. The methanol solvent is distilled to separate methanol from water in the methanol/water mixture, and the methanol is recycled back to the epoxidation reactor for further use, and the produced waste water is sent to a waste water recovery process for treatment.
In the embodiment of the invention, the separation method for preparing propylene oxide by a direct oxidation method comprises the following steps:
feeding the product gas from the reactor into a high-pressure propylene rough separation tower to realize rough separation of propylene and propylene oxide in the high-pressure propylene rough separation tower;
sending the bottom product of the high-pressure propylene crude separation tower to a low-pressure PO crude separation tower to realize separation of PO and methanol;
feeding crude PO and propylene gas taken out from the top of the low-pressure PO crude separation column to a PO absorption column to separate PO and propylene;
pressurizing the gas at the top of the PO absorption tower by a compressor, and then sending the gas to a propylene separation tower;
withdrawing PO from the PO absorption tower and sending it to a PO product tower;
methanol is extracted from the bottom of the low-pressure PO crude separation tower and sent to a methanol recovery tower.
It should be noted that the embodiments of the present invention are not particularly required or limited with respect to the apparatus and devices for implementing the methods described above. As shown in fig. 1 to 3, which can each implement the aforementioned separation method, in an alternative embodiment, as shown in fig. 1, the inlet of the high-pressure propylene crude separation column is connected to the product gas reactor, the upper outlet of the high-pressure propylene crude separation column is connected to the propylene separation column, and the lower outlet is connected to the low-pressure PO crude separation column. The upper outlet of the low-pressure PO rough separation tower is connected with the PO absorption tower, and the lower outlet is connected with the PO absorption tower. The upper outlet of the PO absorption tower is connected with a propylene compressor, the propylene compressor is connected with a propylene separation tower, and the lower outlet of the PO absorption tower is connected with a PO product tower. The lower outlet of the PO product tower is connected with the methanol recovery tower. The methanol recovery tower comprises a first methanol tower and a second methanol tower, the low-pressure PO rough separation tower and the PO product tower are connected with the first methanol tower, and an inlet and an outlet of the first methanol tower are correspondingly connected with an inlet and an outlet of the second methanol tower. The first methanol tower and the second methanol tower are respectively connected with a methanol reactor. In fig. 2, the upper outlet of the high-pressure propylene crude separation tower is connected with a tail gas absorption tower, and inert gas is introduced into the bottom of the high-pressure propylene crude separation tower. In fig. 3, the high pressure propylene crude separation column is provided with an intermediate reboiler that can increase propylene production. The invention realizes the recovery of most propylene by the high-low pressure rough separation tower, and reduces the occurrence of side reactions. The high-low pressure rough separation tower is arranged at the front section of the process, so that most of propylene is recovered, and energy consumption is saved. The temperature of the tower kettle of the high-pressure propylene tower is controlled to slow down the probability of the reaction of PO and water in the tower kettle, so that the occurrence of side reaction can be reduced.
As shown in fig. 1 to 3, the present invention provides three embodiments, which are described in detail below in conjunction with fig. 1 to 3, respectively.
FIG. 1 is a schematic flow chart of a process implemented as follows:
a) The product gas sent from the reactor is sent to a high-pressure propylene crude separation tower T-10,
b) Coarsely separating propylene and propylene oxide in a high-pressure propylene coarse separation tower T-10, sending a tower bottom product to a low-pressure separation tower T-20 to realize PO and methanol separation,
c) The crude PO and propylene gas extracted from the top of the low-pressure PO crude separation tower T-20 are sent to a PO absorption tower T-30 to separate PO and propylene,
d) Methanol at the bottom of the low-pressure PO rough separation tower T-20 is further recovered by removing methanol from a methanol recovery tower T-60/70, the top gas of the PO absorption tower T-30 is pressurized by a propylene compressor K-31 and then is sent to a propylene separation tower T-40, and propylene is extracted from the top of the propylene separation tower T-40 and is sent to a reactor for continuous reaction
e) PO is extracted from the PO absorption tower T-30 to a PO removal refining tower T-50, and methanol extracted from the bottom of the PO absorption tower T-50 is sent to a methanol recovery tower T-60/70.
f) Methanol recovery column T-60/70 separates the methanol from the water and the methanol is recycled back to the reactor.
FIG. 2 is a schematic process flow diagram implemented as follows:
a) The product gas sent from the reactor is sent to a high-pressure propylene crude separation tower T-10, and inert gas such as nitrogen is introduced into the bottom of the high-pressure propylene crude separation tower T-10 for increasing the propylene yield.
b) Coarsely separating propylene and propylene oxide in a high-pressure propylene coarse separation tower T-10, sending a tower bottom product to a low-pressure separation tower T-20 to realize PO and methanol separation,
c) The crude PO and propylene gas extracted from the top of the low-pressure PO crude separation tower T-20 are sent to a PO absorption tower T-30 to separate PO and propylene,
d) Methanol at the bottom of the low-pressure PO rough separation tower T-20 is further recovered by removing methanol from a methanol recovery tower T-60/70, the top gas of the PO absorption tower T-30 is pressurized by a propylene compressor K-31 and then is sent to a propylene separation tower T-40, and propylene is extracted from the top of the propylene separation tower T-40 and is sent to a reactor for continuous reaction
e) PO is extracted from the PO absorption tower T-30 to a PO removal refining tower T-50, and methanol extracted from the bottom of the PO absorption tower T-50 is sent to a methanol recovery tower T-60/70.
f) Methanol recovery column T-60/70 separates the methanol from the water and the methanol is recycled back to the reactor.
g) The top of the high-pressure propylene crude separation tower T-10 is not condensed and passes through a tail gas recovery tower T-80, propylene is recovered from methanol from the methanol tower, and the recovered material is sent to the inlet of the reactor.
FIG. 3 is a schematic process flow diagram implemented as follows:
a) The product gas sent from the reactor is sent to a high-pressure propylene crude separation tower T-10, and inert gas such as nitrogen is introduced into the bottom of the high-pressure propylene crude separation tower T-10 for increasing the propylene yield. Inert gas, such as nitrogen, is introduced into the bottom of the high-pressure propylene crude separation tower T-10 to increase propylene extraction, and the nitrogen is added to help further reduce the oxygen volume fraction in purge gas (oxygen is carried by the product due to decomposition of raw material hydrogen peroxide), so that the safety of the device is enhanced. In order to promote the separation of propylene oxide in the high-pressure propylene rough separation tower, an intermediate reboiler E-11 is adopted, and propylene extraction is increased.
b) Coarsely separating propylene and propylene oxide in a high-pressure propylene coarse separation tower T-10, sending a tower bottom product to a low-pressure separation tower T-20 to realize PO and methanol separation,
c) The crude PO and propylene gas extracted from the top of the low-pressure PO crude separation tower T-20 are sent to a PO absorption tower T-30 to separate PO and propylene,
d) Methanol at the bottom of the low-pressure PO rough separation tower T-20 is further recovered by removing methanol from a methanol recovery tower T-60/70, the top gas of the PO absorption tower T-30 is pressurized by a propylene compressor K-31 and then is sent to a propylene separation tower T-40, and propylene is extracted from the top of the propylene separation tower T-40 and is sent to a reactor for continuous reaction
e) PO is extracted from the PO absorption tower T-30 to a PO removal refining tower T-50, and methanol extracted from the bottom of the PO absorption tower T-50 is sent to a methanol recovery tower T-60/70.
f) Methanol recovery column T-60/70 separates the methanol from the water and the methanol is recycled back to the reactor.
g) The top of the high-pressure propylene crude separation tower T-10 is not condensed and passes through a tail gas recovery tower T-80, propylene is recovered from methanol from the methanol tower, and the recovered material is sent to the inlet of the reactor.
The separation method for preparing propylene oxide by using the direct oxidation method provided by the embodiment comprises the following steps: the product gas sent from the reactor is sent to a high-pressure separation tower, propylene and epoxypropane are roughly separated in the high-pressure separation tower, the tower bottom product is sent to a low-pressure separation tower to realize the separation of PO and methanol, the crude PO and propylene gas extracted from the tower top of the low-pressure separation tower are sent to a PO rough separation tower, PO and propylene are separated, methanol at the bottom of the low-pressure separation tower is further recovered by a methanol recovery tower, the tower top gas of the PO rough separation tower is sent to a propylene separation tower after being pressurized by a compressor, PO is extracted from the PO rough separation tower to a PO refining tower, and methanol extracted from the tower bottom of the PO rough separation tower is sent to a methanol recovery tower. The method provided by the invention is different from the conventional PO separation process, realizes recovery of most of propylene through the high-low pressure rough separation tower, reduces side reaction, and is beneficial to saving energy consumption.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and the scope of the invention should be assessed accordingly to that of the appended claims.
Claims (11)
1. A separation method for preparing propylene oxide by a direct oxidation method, comprising the steps of:
feeding the product gas from the reactor into a high-pressure propylene rough separation tower to realize rough separation of propylene and propylene oxide in the high-pressure propylene rough separation tower;
sending the tower bottom product of the high-pressure propylene crude separation tower to a low-pressure PO crude separation tower to realize separation of PO and methanol;
feeding crude PO and propylene gas withdrawn from the top of the low pressure PO crude separation column to a PO absorber to separate PO from propylene;
pressurizing the gas at the top of the PO absorption tower by a compressor, and then sending the gas to a propylene separation tower;
withdrawing PO from said PO absorber and passing it to a PO product column;
methanol is extracted from the bottom of the low-pressure PO crude separation tower and sent to a methanol recovery tower.
2. The separation method for producing propylene oxide by direct oxidation according to claim 1, wherein an inlet of the high-pressure propylene crude separation column is connected to the product gas reactor, an upper outlet of the high-pressure propylene crude separation column is connected to a propylene separation column, and a lower outlet is connected to a low-pressure PO crude separation column.
3. The separation method for producing propylene oxide by direct oxidation according to claim 2, wherein an upper outlet of the low-pressure PO crude separation column is connected to a PO absorption column and a lower outlet is connected to the PO absorption column.
4. A separation process for the direct oxidation process for the production of propylene oxide according to claim 3, wherein the upper outlet of the PO absorber is connected to a propylene compressor connected to the propylene separation column and the lower outlet of the PO absorber is connected to the PO product column.
5. The separation method for producing propylene oxide by direct oxidation according to claim 4, wherein a lower outlet of the PO product column is connected to the methanol recovery column.
6. The separation method for producing propylene oxide by direct oxidation according to claim 5, wherein the methanol recovery column comprises a first methanol column and a second methanol column.
7. The separation method for preparing propylene oxide by a direct oxidation process according to claim 6, wherein the low pressure PO crude separation column and the PO product column are connected to the first methanol column, and an inlet and an outlet of the first methanol column are correspondingly connected to an inlet and an outlet of the second methanol column.
8. The separation method for producing propylene oxide by direct oxidation according to claim 6, wherein the first methanol tower and the second methanol tower are connected to a methanol removal reactor, respectively.
9. The separation method for producing propylene oxide by direct oxidation according to any one of claims 1 to 8, wherein an upper outlet of the high-pressure propylene crude separation column is connected to a tail gas absorption column.
10. The separation method for producing propylene oxide by direct oxidation according to claim 9, wherein an inert gas is introduced into the bottom of the high-pressure propylene crude separation column.
11. The separation process for the direct oxidation process of any one of claims 1 to 8, wherein the high pressure propylene crude separation column is provided with an intermediate reboiler capable of increasing propylene production.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210412694.4A CN116947786A (en) | 2022-04-19 | 2022-04-19 | Separation method for preparing epoxypropane by direct oxidation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210412694.4A CN116947786A (en) | 2022-04-19 | 2022-04-19 | Separation method for preparing epoxypropane by direct oxidation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116947786A true CN116947786A (en) | 2023-10-27 |
Family
ID=88460683
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210412694.4A Pending CN116947786A (en) | 2022-04-19 | 2022-04-19 | Separation method for preparing epoxypropane by direct oxidation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116947786A (en) |
-
2022
- 2022-04-19 CN CN202210412694.4A patent/CN116947786A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101641343B (en) | Propylene oxide recovery process | |
| KR102138648B1 (en) | A process for refining propylene oxide | |
| US6458856B1 (en) | Separation process for one-step production of dimethyl ether from synthesis gas | |
| CN105622337B (en) | Novel reactive distillation coupling process and device for separating liquid-phase product of ethylene glycol prepared from coal | |
| CN103172486B (en) | A kind of method of Propylene recovery from Direct Epoxidation reaction product | |
| WO1991016288A1 (en) | Process for separating impurities from aqueous solution of crude ethanol | |
| WO1992021638A1 (en) | Process for purifying aqueous crude ethanol solution | |
| RU2689569C2 (en) | Methanol processing method in the process of producing dimethyl oxalate by gas synthesis | |
| CN103172596B (en) | Propylene oxide refining method | |
| JP6681676B2 (en) | Method and apparatus for the cyclic treatment and purification of propylene | |
| CN103172594B (en) | Method for refining and purifying propylene oxide | |
| CN114920630B (en) | Continuous production process and equipment for ethylene glycol monovinyl ether | |
| CN107987038B (en) | Epoxidation process material separation system and epoxidation process material separation method | |
| CN111574478B (en) | Process for preparing epoxypropane by oxidizing propylene with hydrogen peroxide | |
| CN105541555A (en) | Reactive rectification method and device for separating ethylene glycol, propylene glycol and butylene glycol | |
| CN116947786A (en) | Separation method for preparing epoxypropane by direct oxidation method | |
| CN103172595B (en) | Method for refining propylene oxide from products of direct epoxidation reaction | |
| RU2408569C2 (en) | Method of producing allyl alcohol | |
| EP2980082B1 (en) | Ethylene oxide production process | |
| CN113968830B (en) | Separation method of epoxypropane stream and separation method of epoxidation reaction product and propylene epoxidation method | |
| CN106278896B (en) | The method of separating dimethyl carbonate during synthesizing dimethyl oxalate | |
| CN110041298B (en) | Method and device for removing and converting trace amount of alkylene oxide | |
| CN113072427B (en) | Method for recovering propylene glycol ether and propylene glycol | |
| CN113548966A (en) | Method for treating by-product methyl formate in process of preparing ethylene glycol from coal | |
| JP2007246486A (en) | Methanol manufacturing plant and methanol manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |