CN115557834B - Process for separating mixed butyraldehyde - Google Patents
Process for separating mixed butyraldehyde Download PDFInfo
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- CN115557834B CN115557834B CN202110752194.0A CN202110752194A CN115557834B CN 115557834 B CN115557834 B CN 115557834B CN 202110752194 A CN202110752194 A CN 202110752194A CN 115557834 B CN115557834 B CN 115557834B
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- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
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Abstract
The invention relates to a separation process for preparing mixed butyraldehyde by low-pressure oxo synthesis, belonging to the technical field of chemical separation. According to the process for separating the mixed butyraldehyde, reaction products of the oxo-synthesis reactor enter the middle part of a butyraldehyde isomer tower through a feed inlet after being subjected to separation and compression, the light components in the reaction products are less than or equal to 4wt%, the n-isobutyraldehyde ratio is 10-13:1, the light components are extracted from the top of a light component removing section at the top of the tower, the isobutyraldehyde is extracted from the side line at the upper part of the tower, and the n-butyraldehyde mixture is extracted from the bottom of the tower. The invention has the advantages of small equipment investment, simple operation, lower energy consumption and high concentration of isobutyraldehyde products.
Description
Technical Field
The invention relates to a separation process for preparing mixed butyraldehyde by low-pressure oxo synthesis, belonging to the technical field of chemical separation.
Background
N-butyraldehyde is colorless transparent liquid at normal temperature, has asphyxia smell, and is commonly used as an intermediate of resin, plastic plasticizer, vulcanization accelerator, pesticide and the like.
The isobutyraldehyde is colorless liquid at normal temperature, has pungent smell, is an important raw material in chemical production, is commonly used for synthesizing cellulose ester, essence, perfume and the like, can be used for preparing rubber vulcanization accelerators and anti-aging agents, and is a raw material for producing isobutanol, neopentyl glycol, methacrylic acid (MAA) and Methyl Methacrylate (MMA).
The industrial butyraldehyde is produced by using propylene and synthetic gas as raw materials, generating stable butyraldehyde through oxo synthesis reaction, and obtaining n-butyraldehyde and iso-butyraldehyde products through fractionation. The industrial production process of butyraldehyde mainly comprises three steps: (1) a high pressure cobalt process; (2) a medium pressure rhodium process; (3) Low pressure rhodium Process. The boiling point of n-butyraldehyde is 75.7 ℃, the boiling point of iso-butyraldehyde is 64.0 ℃, and the method of precise rectification is generally adopted for separating and mixing butyraldehyde, but the investment of the existing three-tower or double-tower rectification equipment is large, and the energy consumption is high.
CN112299979a discloses a method for extracting isobutyraldehyde, which comprises a butyraldehyde isomer rectifying tower and an isobutyraldehyde rectifying tower, wherein a mixture containing n-butyraldehyde and isobutyraldehyde is initially separated in the butyraldehyde isomer rectifying tower, the n-isobutyraldehyde mixture is extracted from the tower top, and the n-butyraldehyde is extracted from the tower bottom; the n-isobutyraldehyde mixture enters an isobutyraldehyde rectifying tower for purification, the isobutyraldehyde is extracted from a side line, and the n-butyraldehyde is extracted from a tower kettle. The method has the advantages of high equipment investment and high requirement on the purity of the isobutyraldehyde in the mixed butyraldehyde in side line operation.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a mixed butyraldehyde separation process which has the advantages of small equipment investment, simple operation, lower energy consumption and high isobutyraldehyde product concentration.
The invention provides a separation process of oxo reaction products containing light components, isobutyraldehyde, n-butyraldehyde and heavy components, wherein a butyraldehyde isomer tower added with a light component removal section is used for separating each component, the concentration of the isobutyraldehyde after separation is more than or equal to 99.6% (wt), and the concentration of the light components and the isobutyraldehyde in the n-butyraldehyde is less than or equal to 0.01% (wt).
The basic production process of the invention is as follows: the reaction product of the oxo reactor enters the middle part of a butyraldehyde isomer tower through a feed inlet after being separated and compressed, the light component in the reaction product is less than or equal to 4 percent (wt), the n-isobutyraldehyde ratio is 10-13:1, the light component is extracted from the top of a light component removing section at the top of the tower, the isobutyraldehyde is extracted from the side line at the upper part of the tower, and the n-butyraldehyde mixture is extracted from the bottom of the tower.
The top of the butyraldehyde isomeride tower is provided with a light component removing section, a light component outlet at the top of the light component removing section is sequentially connected with a condenser, a reflux tank and a reflux pump through pipelines, the reflux pump is connected with a reflux port of the butyraldehyde isomeride tower, the top of the reflux tank is provided with a light component product extraction line, the upper part of the butyraldehyde isomeride tower is provided with an isobutyraldehyde product extraction line, the bottom of the butyraldehyde isomeride tower is connected with a reboiler, and the bottom of the butyraldehyde isomeride tower is provided with a n-butyraldehyde mixture extraction line.
The butyraldehyde isomerism tower is a plate type rectifying tower, adopts a fixed valve tray, has 119 trays, is provided with a feeding port positioned on a 54 th tray, and is provided with a lateral line extraction port positioned on a 10 th tray.
The light component removing section is based on the original butyraldehyde isomer tower, the number of plates of the tower is increased by 9, the number of plates is increased at the top of the tower, and a valve fixing tray is adopted.
The valve fixing tray is a semi-elliptic valve body formed by directly punching a tray structural material, and has the characteristics of being beneficial to reducing the liquid level gradient of liquid, reducing the back mixing of the liquid on the tray and enhancing the mass transfer efficiency.
The operation conditions of the rectifying tower are as follows: the pressure at the top of the tower is 0.12-0.20 MPa, preferably 0.16MPa; the side extraction temperature is 72-84 ℃, preferably 78-79 ℃; the temperature of the tower top is controlled to be 66-75 ℃, preferably 69-71 ℃; the temperature of the tower kettle is controlled to be 97-109 ℃, preferably 100-103 ℃; the reflux ratio is controlled between 40 and 42.
The tower top products of the butyraldehyde isomeride tower mainly comprise water, carbon dioxide, propylene and propane, the side-draw products mainly comprise isobutyraldehyde, and the tower bottom products mainly comprise n-butyraldehyde, isobutanol, n-butanol and the like.
In summary, the beneficial effects of the invention are as follows:
the invention provides a separation process of oxo reaction products containing light components, isobutyraldehyde, n-butyraldehyde and heavy components. The mixed product enters the middle part of a butyraldehyde isomer tower added with a light component removing section, the light component is extracted from the top of the light component removing section through rectification, isobutyraldehyde is extracted from the side line at the upper part of the tower, and the n-butyraldehyde mixture is extracted from the bottom of the tower. After separation, the concentration of the isobutyraldehyde is more than or equal to 99.6% (wt), the concentration of the light component and the concentration of the isobutyraldehyde in the n-butyraldehyde are less than or equal to 0.01% (wt), and the mixture of the light component, the isobutyraldehyde and the n-butyraldehyde is completely separated. The method is improved from a double-tower process to a single-tower process, has the advantages of less equipment investment, low material and energy consumption of the device and simple operation.
Drawings
FIG. 1 is a schematic diagram of the structure of a butyraldehyde isomer column of the invention;
FIG. 2 is a schematic diagram of a valve body of a fixed valve tray;
in the figure: 1. a butyraldehyde isomer column; 2. a light component removal section; 3. a condenser; 4. a reflux drum; 5. a reflux pump; 6. a reboiler; 7. a light component product take-off line; 8. an isobutyraldehyde product take-off line; 9. a n-butyraldehyde mixture withdrawal line.
Detailed Description
The present invention will be further illustrated by the following examples, but the present invention is not limited to these examples. The nature of the invention and the scope of the invention will be more fully understood by these examples and further the process characteristics described herein.
In the process for separating the oxo reaction product containing the light components, the isobutyraldehyde and the n-butyraldehyde, as shown in fig. 1, the mixed product enters the middle part of a butyraldehyde isomerism tower 1, the light components and the isobutyraldehyde are separated by a light component removal section 2 through rectification, the light components are condensed into a gas-liquid phase mixture by a condenser 3, the gas-liquid phase mixture enters a reflux tank 4, the gas-phase light components are extracted from a light component product extraction line 7 at the top of the tank, the liquid phase returns to the butyraldehyde isomerism tower 1 by a reflux pump 5, the isobutyraldehyde product is extracted from an isobutyraldehyde product extraction line 8 at the upper part of the tower, and the n-butyraldehyde mixture is extracted from a n-butyraldehyde mixture extraction line 9 at the bottom of the tower.
The rectifying tower is a plate rectifying tower, adopts a fixed valve tray, has 119 trays, is provided with a feed inlet positioned on the 54 th tray, and is provided with a side line extraction outlet positioned on the 10 th tray.
The light component removing section 2 is a rectifying section with 9 tower plates, is added at the top of the butyraldehyde isomeride tower 1, and adopts a valve fixing tower tray.
The valve fixing tower plate is a semi-elliptic valve body formed by directly punching tower plate structural materials, and has the characteristics of being beneficial to reducing the liquid level gradient of liquid, reducing the back mixing of the liquid on the tower plate and enhancing the mass transfer efficiency.
According to the process flow, the operating conditions of the butyraldehyde isomerism tower are as follows: the pressure of the tower top is 0.12-0.20 MPa, the side stream extraction temperature is 72-84 ℃, the temperature of the tower top is 66-75 ℃, the temperature of the tower bottom is 97-109 ℃, and the reflux ratio is 40-42.
Examples 1 to 5
Isobutyraldehyde was extracted according to the above process, and the feed composition of the butyraldehyde isomer column in each example was as shown in Table 1 below:
examples 1-5 butyraldehyde isomer column operating conditions were:
example 1: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.3 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 40.1.
Example 2: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.2 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 39.9.
Example 3: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.3 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 40.0.
Example 4: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.3 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 40.0.
Example 5: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.3 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 40.0.
TABLE 1 butyraldehyde isomer column feed composition
The isobutyraldehyde product isolated by the method of the present invention is analyzed as follows in Table 2:
TABLE 2 lateral line isobutyraldehyde product analysis data
The purity of the separated isobutyraldehyde product is higher, and the purity and impurity content of the isobutyraldehyde product meet the standards of the corresponding industry.
Example 6
Using the same process flow, feed composition, and butyraldehyde isomerate column operating conditions as in example 1 were: the pressure at the top of the tower is 0.16MPa, the side stream extraction temperature is 78.5 ℃, the temperature at the top of the tower is 70.1 ℃, the temperature at the bottom of the tower is 102.0 ℃, and the mass reflux ratio is 39.6.
The mass concentration of the isobutyraldehyde product was controlled to 99.60% by simulation using the chemical simulation software Aspen Plus, and the energy consumption of example 6 was converted to standard oil by converting the energy consumption to GB/T50441-2016, and the results are shown in Table 3.
TABLE 3 energy consumption and product yield consumed in example 6
Comparative example 1
The comparative example uses a conventional float valve tray instead of a fixed valve tray, uses the rectification method described in example 6 to refine the oxo reaction product containing light components, isobutyraldehyde, n-butyraldehyde and heavy components, and uses the mixed feed composition and the same product purity requirement in example 6, the amount of the mixed product is 24.85t/h.
The floating valve tray is characterized in that a valve plate capable of moving up and down is arranged at each sieve pore, when the gas speed of the sieve pore is too high, the valve plate is jacked up and lifted, when the gas speed of the sieve pore is low, the valve plate descends due to dead weight, and the lifting position of the valve plate is automatically adjusted along with the gas amount; the comparative example was carried out in the same manner as in example 6, except that all the equipment to be heated was heated with steam and all the equipment to be cooled was cooled with condensed water.
Example 6 and comparative example 1 were simulated by chemical simulation software Aspen Plus and energy consumption was converted by GB/T50441-2016, and the energy consumption of example 6 and comparative example 1 was converted to standard oil and the isobutyraldehyde product concentrations of example 6 and comparative example 1 were also compared, and the results are shown in table 4.
Table 4 comparative table of energy consumption consumed by the rectification method of example 6 and comparative example 1
As can be seen from Table 4, the mixed butyraldehyde separation process of the invention, which is provided with the butyraldehyde isomer tower added with the light component removal section, has high purity and good energy-saving effect when treating a oxo reaction product containing light components, isobutyraldehyde, n-butyraldehyde and heavy components. Compared with the floating valve tray used in the comparative example 1, the concentration of the isobutyraldehyde product is qualified, meets the index that the purity of the isobutyraldehyde superior product in the industry standard HG/T4965-2016 is more than 99.2 weight percent, and simultaneously saves energy by about 6 percent.
Comparative example 2
The present comparative example uses a conventional distillation method for removing light ends and then separating n-isobutyraldehyde to refine the oxo reaction product containing light components, isobutyraldehyde, n-butyraldehyde and heavy components, and uses the mixed feed composition and the same product purity requirement in example 6, and the amount of the mixed product is 24.85t/h.
The existing conventional mixed butyraldehyde separation process flow comprises the following steps: the mixed product enters the middle part of a light component removal tower, the top pressure of the light component removal tower is 0.38MPaG, the top temperature of the tower is 86.5 ℃, the bottom pressure of the tower is 0.41MPaG, the bottom temperature of the tower is 130.0 ℃, the mass reflux ratio is 6.0, after rectification, the top gas phase is condensed into a gas-liquid phase mixture through a condenser, the gas phase light component product enters a reflux tank, the gas phase light component product is extracted from the top of the tank, the liquid phase returns to the rectifying tower through a reflux pump, the normal isobutyraldehyde mixture without light components enters the middle part of a butyraldehyde isomer tower through a liquid pump of the light component removal tower, the top pressure of the butyraldehyde isomer tower is 0.60MPaG, the top temperature of the tower is 80.0 ℃, the bottom pressure of the tower is 0.64MPaG, the bottom temperature of the tower is 101.0 ℃, the mass reflux ratio is 30, the top gas phase is condensed into a gas-liquid phase mixture through a condenser, the gas-liquid phase mixture enters the reflux tank, the condensed liquid phase is extracted through the reflux pump, a part of isobutyraldehyde product is extracted as a isobutyraldehyde product, and a part returns to the rectifying tower to be reflux; all the equipment needing to be heated is heated by steam, and all the equipment needing to be cooled is cooled by condensed water.
Comparative example 3
Refining oxo reaction products of light components, isobutyraldehyde, n-butyraldehyde and heavy components by adopting a rectification method in a patent CN112299979A, and adopting the mixed feed composition and the same product purity requirement in the example 6, wherein the amount of the mixed product is 24.85t/h; the process parameters were fully simulated according to the data disclosed in example 1 of patent CN112299979 a.
The temperature of the tower bottom of the isobutyraldehyde rectifying tower is controlled at 103.0 ℃, the temperature of the tower top is controlled at 75.9 ℃, the pressure of the tower top is 0.15MPa, and the lateral line temperature is 77.5 ℃ to obtain the isobutyraldehyde product.
The temperature of the bottom of the butyraldehyde isomer rectifying tower is controlled at 106.0 ℃, the temperature of the top of the tower is controlled at 81.5 ℃, the pressure of the top of the tower is 0.15MPa, and the reflux ratio is controlled at 3.0:1.
examples 6 and comparative examples 2 to 3 were each calculated according to the isobutyraldehyde yield of 99% and the purity of 99.6%, simulated by the chemical simulation software Aspen Plus, and the energy consumption was converted by GB/T50441-2016, and the energy consumption of examples 6 and comparative examples 2 to 3 was converted to a standard oil, and the results are shown in Table 5.
TABLE 5 comparison of energy consumption consumed by the rectification methods of example 6 and comparative examples 2-3
As can be seen from Table 5, the mixed butyraldehyde separation process of the invention, which is provided with the butyraldehyde isomer tower added with the light component removal section for direct rectification, has obvious energy-saving characteristics when treating a oxo reaction product containing light components, isobutyraldehyde, n-butyraldehyde and heavy components. Compared with the conventional rectification method for firstly removing light components and then separating n-isobutyraldehyde in comparative example 2, the energy consumption of the device is reduced by about 19 percent, 10 tower plates are added in a butyraldehyde isomer tower, but one rectification tower, two heat exchangers, one pump and other equipment are reduced, so that the equipment investment is saved; compared with the rectification method of the prior patent CN112299979A, the energy consumption is reduced by about 42 percent.
Claims (3)
1. A process for separating mixed butyraldehyde is characterized in that: the reaction product of the oxo reactor enters the middle part of a butyraldehyde isomeride tower (1) through a feed inlet after being separated and compressed, the light component in the reaction product is less than or equal to 4wt%, the normal isobutyraldehyde ratio is 10-13:1, the light component is extracted from the top of a tower top light component removing section (2), the isobutyraldehyde is extracted from the side line at the upper part of the tower, and the normal butyraldehyde mixture is extracted from the bottom of the tower;
the top of the butyraldehyde isomerism tower (1) is provided with a light component removing section (2), a light component outlet at the top of the light component removing section (2) is sequentially connected with a condenser (3), a reflux tank (4) and a reflux pump (5) through pipelines, the reflux pump (5) is connected with a reflux port of the butyraldehyde isomerism tower (1), the top of the reflux tank (4) is provided with a light component product extraction line (7), the upper part of the butyraldehyde isomerism tower (1) is provided with an isobutyraldehyde product extraction line (8), the bottom of the butyraldehyde isomerism tower (1) is connected with a reboiler (6), and the bottom of the butyraldehyde isomerism tower (1) is provided with a n-butyraldehyde mixture extraction line (9);
the butyraldehyde isomeride tower (1) is a plate type rectifying tower, adopts a fixed valve tray, has 119 trays, is provided with a feeding port positioned on a 54 th tray, and is provided with a lateral line extraction port positioned on a 10 th tray;
the light component removing section (2) is a rectifying section with 9 tower plates and adopts a solid valve tower tray;
the valve fixing tray is a semi-elliptic valve body formed by directly punching a tray structure material;
the operating conditions of the butyraldehyde isomerism tower (1) are as follows: the pressure at the top of the tower is 0.12-0.20 MPa; the side extraction temperature is 72-84 ℃, the tower top temperature is controlled at 66-75 ℃, the tower bottom temperature is controlled at 97-109 ℃, and the reflux ratio is controlled at 40-42.
2. The process for separating mixed butyraldehyde of claim 1, wherein: the operating conditions of the butyraldehyde isomerism tower (1) are as follows: the pressure at the top of the tower is 0.16MPa; the side extraction temperature is 78-79 ℃, the tower top temperature is 69-71 ℃, and the tower bottom temperature is 100-103 ℃.
3. The process for separating mixed butyraldehyde of claim 1, wherein: the top product of the butyraldehyde isomerism tower (1) comprises water, carbon dioxide, propylene and propane, the side-draw product comprises isobutyraldehyde, and the bottom product comprises n-butyraldehyde, isobutanol and n-butanol.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102580337A (en) * | 2012-01-19 | 2012-07-18 | 天津大学 | Mixed butyraldehyde separation device and application of packed towers |
| CN111302922A (en) * | 2020-03-27 | 2020-06-19 | 北京诺维新材科技有限公司 | Rectification separation method and rectification system |
| CN112299979A (en) * | 2020-11-27 | 2021-02-02 | 南京诚志清洁能源有限公司 | Method for extracting isobutyraldehyde |
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- 2021-07-02 CN CN202110752194.0A patent/CN115557834B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102580337A (en) * | 2012-01-19 | 2012-07-18 | 天津大学 | Mixed butyraldehyde separation device and application of packed towers |
| CN111302922A (en) * | 2020-03-27 | 2020-06-19 | 北京诺维新材科技有限公司 | Rectification separation method and rectification system |
| CN112299979A (en) * | 2020-11-27 | 2021-02-02 | 南京诚志清洁能源有限公司 | Method for extracting isobutyraldehyde |
Non-Patent Citations (2)
| Title |
|---|
| 丁醇异构物塔的模拟研究与优化改造;李治水;聂增来;庞栓林;王松;谢智勇;李云辉;;高校化学工程学报(05);全文 * |
| 自适应浮阀塔板HAV~(TH)的操作特性;钱建兵, 亓荣彬, 朱慎林;石油炼制与化工(04);全文 * |
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