CN111393345A - Preparation method of limonene hydroperoxide - Google Patents
Preparation method of limonene hydroperoxide Download PDFInfo
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- CN111393345A CN111393345A CN202010274601.7A CN202010274601A CN111393345A CN 111393345 A CN111393345 A CN 111393345A CN 202010274601 A CN202010274601 A CN 202010274601A CN 111393345 A CN111393345 A CN 111393345A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
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- C07C407/00—Preparation of peroxy compounds
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/0093—Microreactors, e.g. miniaturised or microfabricated reactors
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/12—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electromagnetic waves
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2601/00—Systems containing only non-condensed rings
- C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
- C07C2601/16—Systems containing only non-condensed rings with a six-membered ring the ring being unsaturated
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Abstract
The invention discloses a preparation method of limonene hydroperoxide. The method comprises the steps of adopting an integrated continuous flow reaction device of a photochemical microchannel reactor, continuously conveying a mixed solution containing terpinolene, a photosensitizer and a solvent to a fluid module of the photochemical microchannel reactor through a feeding hole of the photochemical microchannel reactor, simultaneously supplying oxygen to the fluid module, supplying illumination to the fluid module, carrying out photosensitive oxidation reaction in the fluid module, and reacting to obtain the limonene hydroperoxide. The preparation process disclosed by the invention is novel, efficient, green and sustainable, and compared with the traditional intermittent reaction, the preparation process has the characteristics of accurate temperature and pressure control, good mass transfer effect, greatly shortened reaction time, high light source utilization rate, less side reactions, low energy consumption, high yield and the like, and has a certain industrial prospect.
Description
Technical Field
The invention belongs to the technical field of essential oil intermediate synthesis, and particularly relates to a preparation method of limonene hydroperoxide.
Background
Limonene hydroperoxide is a key intermediate for the synthesis of terpinen-4-ol by a photosensitive oxidation method. Terpinene-4-ol, also called 4-terpineol, is a monocyclic monoterpene alcohol which is a colorless oily liquid, slightly soluble in water, presents warm pepper, light earth and lily fragrance, has the functions of diminishing inflammation, detoxifying, resisting bacteria and the like, particularly has strong antibacterial action on fungi, common pathogenic bacteria and drug-resistant bacteria, and is widely applied to the field of modulation of high-grade essential oil.
Currently, the main source of terpinen-4-ol is obtained by rectification of tea tree oil. With the continuous expansion of the market, people have a larger demand space for terpinen-4-ol, but the shortage of raw materials of tea tree oil is limited, so that the situation of short supply and demand becomes more serious. In order to solve the problem, a new supply channel of terpinene-4-alcohol needs to be developed, and artificial chemical synthesis is a new way for solving the problem of supply shortage of terpinene-4-alcohol.
So far, three methods for artificially and chemically synthesizing terpinen-4-ol are mainly used, the first method is the simplest and efficient method which takes 1, 4-cineole as a raw material and obtains the terpinen-4-ol through catalytic ring opening, but the method is also limited by the shortage of 1, 4-cineole raw materials; secondly, terpinolene, one of turpentine components, is used as a raw material, and terpinolene-4-alcohol is obtained through three steps of epoxidation, isomerization and hydrogenation, but the catalyst used in the process has poor catalytic performance and is difficult to recover; the third method is also to use terpinolene as a raw material, and obtain terpinolene-4-alcohol through three steps of photosensitive oxidation, reduction and hydrogenation, but in the photosensitive oxidation process of terpinolene, the experimental device adopted is the combination of a glass flask and a high-pressure mercury lamp, the combination lacks effective gas-liquid contact and uniform irradiation of reaction solution, and the high-pressure mercury lamp contains a large amount of ultraviolet rays, and generates a large amount of heat after long-time irradiation, so that the reaction temperature is not easy to control and obvious byproducts are formed. In addition, the reaction scale is greatly limited by the constraints of the experimental device.
Therefore, a preparation method which is simple to operate, green, efficient, short in reaction time, high in yield and easy for large-scale production of limonene hydroperoxide needs to be found.
Disclosure of Invention
In order to solve the above limitations, the invention provides a preparation method of limonene hydroperoxide, which has the advantages of simple operation, greenness, high efficiency, short reaction time, high yield, easy mass production and the like.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a preparation method of limonene hydroperoxide is characterized in that a continuous flow reaction device of a photochemical microchannel reactor is adopted, a mixed solution containing terpinolene, a photosensitizer and a solvent is continuously conveyed to a fluid module of the photochemical microchannel reactor through a feeding hole of the photochemical microchannel reactor, oxygen is supplied to the fluid module, illumination is supplied to the fluid module, and the mixed solution is subjected to photosensitive oxidation reaction in the fluid module to obtain limonene hydroperoxide.
Further, in the photosensitive oxidation process, the temperature in the fluid module is-10 ℃ to 50 ℃, preferably 10 ℃ to 30 ℃, and more preferably 20 ℃; the internal pressure is 0 to 18bar, preferably 6 to 12bar, more preferably 8 bar.
Further, the residence time of the photosensitive oxidation reaction is 30s to 150s, preferably 50s to 80 s.
Further, the photosensitizer is rose bengal, methylene blue, tetraphenylporphyrin and derivatives, phthalocyanine and derivatives or eosin, preferably rose bengal, methylene blue or tetraphenylporphyrin derivatives.
Further, the quantity ratio of the photosensitizer to terpinolene is 0.0001-0.1, preferably 0.002-0.01.
Further, the solvent is methanol, ethanol, isopropanol, dichloromethane or water, preferably ethanol or isopropanol.
Further, the mass ratio of the solvent to terpinolene in the mixed solution is 1-100 times, preferably 5-60 times.
Further, the step of "supplying oxygen to the fluid module" is specifically to supply pure oxygen or a gas containing oxygen into the fluid module, and preferably the oxygen has a purity of 99.999%.
Further, the light source for "providing illumination" is selected from one of a halogen lamp, a xenon lamp, a mercury lamp, and an L ED lamp, preferably L ED as the light source.
Further, the photochemical microchannel reactor comprises one or more serially connected fluid modules, wherein each fluid module is provided with illumination by a light source; the depth of the internal channel of the photochemical microchannel reactor is 100 mu m-10 mm.
Further, the structure of the fluid module in the photochemical microchannel reactor is a microtube-shaped structure, a groove-shaped structure, a T-shaped structure, a spherical structure, an umbrella-shaped structure or a heart-shaped structure; the fluid module is made of special glass, silicon carbide, corrosion-resistant alloy or fluorine-containing polymer.
The invention has the beneficial effects that:
(1) in the photochemical microchannel reactor, the mass transfer efficiency and the heat transfer efficiency are high, the temperature and the pressure in the whole process are accurately controlled, the reaction time is short, and the conversion rate and the selectivity of the reaction are obviously improved.
(2) L ED is used as a light source, so that the heat dissipation is low, the energy consumption is low, the light source is pure, 6 specific wavelengths can be provided, the light intensity can be adjusted, the optimal light source is selected according to the absorption spectrum of the photosensitizer, and the utilization rate of the light source is improved.
(3) The method has the advantages of simple operation, high production efficiency, no pollution to equipment and environment, seamless amplification, suitability for large-scale continuous preparation and convenience for industrial utilization.
Drawings
FIG. 1 is a schematic diagram showing the structure of a continuous flow reactor of the photochemical microchannel reactor in example 1;
FIG. 2 is a hydrogen spectrum of limonene hydroperoxide prepared in example 1;
FIG. 3 is a carbon spectrum of limonene hydroperoxide from example 1;
in the figure, 1-injection pump, 2-mass flow controller, 3-photochemical microchannel reactor, 4-fluid module, 5-L ED light source and 6-product collector.
Detailed Description
The invention is further described below with reference to specific preferred examples, but the scope of protection of the invention is not limited to the following examples.
Example 1
(1) Preparing a solution: mixing 5g terpinolene and 276g ethanol to obtain a terpinolene solution, then adding 0.071g rose bengal into the solution, and uniformly stirring to obtain the photosensitization reaction solution.
(2) As shown in fig. 1, the continuous flow reactor of the photochemical microchannel reactor comprises a photochemical microchannel reactor 3, wherein a fluid module 4 and an L ED light source 5 are arranged inside the photochemical microchannel reactor 3, the fluid module 4 is of a microtube structure, a feed inlet is arranged at the left part of the photochemical microchannel reactor 3, the injection pump 1 for conveying the photosensitization reaction liquid and the mass flow controller 2 for conveying oxygen are respectively connected with the feed inlet, and a discharge outlet connected with a product collector 6 is arranged at the right part of the photochemical microchannel reactor.
Pumping the photosensitization reaction liquid prepared in the step (1) into a fluid module 4 in a photochemical micro-channel reactor 3 by using an injection pump 1 at the inlet flow rate of 1.5m L/min, then opening an oxygen valve, regulating the flow rate to be 10m L/min by using a mass flow controller 2, setting the module reaction temperature to be 20 ℃, controlling the system pressure to be 8bar, starting a L ED light source 5 at 4000K, regulating the light source intensity to be 100%, setting the light source cooling temperature to be 20 ℃, after the photosensitization oxidation reaction is initiated, keeping the time to be 60s, obtaining a crude product of limonene hydroperoxide at a discharge port of the photochemical micro-channel reactor 3, detecting by using a high performance liquid chromatography (HP L C), and calculating by an external standard method to obtain the conversion rate of terpinolene to be 100% and the selectivity of limonene hydroperoxide to be 61.2%.
Example 2
(1) Preparing a solution: 5g of terpinolene is mixed with 276g of ethanol to obtain a terpinolene solution, then 0.048g of methylene blue is added into the solution, and the mixture is stirred uniformly to obtain the photosensitization reaction liquid.
(2) The continuous flow reaction device of the photochemical microchannel reactor shown in the figure 1 is adopted, a syringe pump 1 is used for pumping the photosensitization reaction liquid prepared in the step (1) into a fluid module 4 in a photochemical microchannel reactor 3 at the inlet flow rate of 1.5m L/min, then an oxygen valve is opened, the flow rate is regulated and controlled to be 10m L/min through a mass flow controller 2, the module reaction temperature is set to be 20 ℃, the system pressure is controlled to be 8bar, a L ED light source with the wavelength of 610nm is started, the light source intensity is regulated to be 100%, the light source cooling temperature is set to be 20 ℃, the retention time is 60s after the photosensitization oxidation reaction is initiated, a crude product of limonene hydroperoxide is obtained at a discharge port of the photochemical microchannel reactor 3, the percent conversion rate of terpinolene reaches 100% through high performance liquid chromatography (HP L C), and the selectivity of limonene hydroperoxide reaches 59.8% through external standard method calculation.
Example 3
(1) Preparing a solution: 5g of terpinolene was mixed with 276g of ethanol to obtain a terpinolene solution, and then 0.057g of meso-tetra (4-carboxyphenyl) porphyrin was added to the solution and stirred uniformly to obtain a photosensitization reaction solution.
(2) The continuous flow reaction device of the photochemical microchannel reactor shown in the figure 1 is adopted, a syringe pump 1 is used for pumping the photosensitization reaction liquid prepared in the step (1) into a fluid module 4 in a photochemical microchannel reactor 3 at the inlet flow rate of 1.5m L/min, then an oxygen valve is opened, the flow rate is regulated and controlled to be 10m L/min through a mass flow controller 2, the module reaction temperature is set to be 20 ℃, the system pressure is controlled to be 8bar, a L ED light source with the wavelength of 405nm is started, the light source intensity is regulated to be 100%, the light source cooling temperature is set to be 20 ℃, the retention time is 60s after the photosensitization oxidation reaction is initiated, a crude product of limonene hydroperoxide is obtained at a discharge port of the photochemical microchannel reactor 3, the percent conversion rate of terpinolene reaches 100% through high performance liquid chromatography (HP L C), and the selectivity of limonene hydroperoxide reaches 50.8% through external standard method calculation.
Example 4
(1) Preparing a solution: mixing terpinolene 10g and isopropanol 549g to obtain terpinolene solution, adding rose bengal 0.0213g into the solution, and stirring to obtain photosensitization reaction solution.
(2) The continuous flow reaction device of the photochemical microchannel reactor shown in the figure 1 is adopted, a syringe pump 1 is used for pumping the photosensitization reaction liquid prepared in the step (1) into a fluid module 4 in a photochemical microchannel reactor 3 at the inlet flow rate of 2m L/min, then an oxygen valve is opened, the flow rate is regulated and controlled to be 10m L/min through a mass flow controller 2, the module reaction temperature is set to be 20 ℃, the system pressure is controlled to be 8bar, a L ED light source with the pressure of 4000K is started, the light source intensity is regulated to be 100%, the light source cooling temperature is set to be 20 ℃, after the photosensitization oxidation reaction is initiated, the residence time is 50s, a crude product of limonene hydroperoxide is obtained at a discharge port of the photochemical microchannel reactor 3, the terpene terpinolene conversion rate reaches 100% through high performance liquid chromatography (HP L C) detection, and the selectivity of the limonene hydroperoxide reaches 62.3% through external standard method calculation.
Comparative example 1
(1) Preparing a solution: mixing 5g terpinolene and 276g ethanol to obtain a terpinolene solution, then adding 0.071g rose bengal into the solution, and uniformly stirring to obtain the photosensitization reaction solution.
(2) And (2) putting the photosensitization reaction liquid into a traditional intermittent photochemical reactor, illuminating the reactor by using a high-pressure mercury lamp, supplying oxygen into the reactor to initiate a photosensitization oxidation reaction, reacting for 4-6 hours, detecting by using a high performance liquid chromatography (HP L C), and calculating by using an external standard method to obtain the terpinolene conversion rate reaching 68% and the limonene hydroperoxide selectivity reaching 35%.
Comparative example 1 compared to example 1, the conversion of terpinolene and the selectivity of limonene hydroperoxide were higher for example 1 than for comparative example 1; the embodiment 1 adopts the photochemical microchannel reactor, has excellent mass and heat transfer efficiency, and the precise temperature control can effectively avoid the decomposition of limonene hydroperoxide caused by the temperature rise in the reaction process; the irradiation time of the light source can be accurately controlled through the flow of the pump, and the further oxidation of limonene hydroperoxide caused by long-time irradiation can be effectively avoided, so that the conversion rate of terpinolene and the selectivity of limonene hydroperoxide are greatly improved.
The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-described embodiments. All technical schemes belonging to the idea of the invention belong to the protection scope of the invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention, and such modifications and embellishments should also be considered as within the scope of the invention.
Claims (10)
1. A preparation method of limonene hydroperoxide is characterized by comprising the following steps: continuously conveying a mixed solution containing terpinolene, a photosensitizer and a solvent to a fluid module of the photochemical microchannel reactor through a feed inlet of the photochemical microchannel reactor, simultaneously supplying oxygen to the fluid module, and providing illumination to the fluid module, wherein the mixed solution is subjected to a photosensitive oxidation reaction in the fluid module to obtain the limonene hydroperoxide.
2. The method for preparing limonene hydroperoxide according to claim 1, wherein during said photosensitive oxidation reaction, the temperature in said fluid module is-10 ℃ to 50 ℃ and the pressure is 0 bar to 18 bar.
3. The process for the preparation of limonene hydroperoxide according to claim 1 or 2, wherein said photo sensitive oxidation reaction has a residence time of 30-150 s.
4. The process for the preparation of limonene hydroperoxide according to claim 1 or 2, wherein said photosensitizer is rose bengal, methylene blue, tetraphenylporphyrin and derivatives, phthalocyanine and derivatives or eosin.
5. The method for producing limonene hydroperoxide according to claim 1, wherein the amount ratio of photosensitizer to terpinolene in said mixed solution is 0.0001-0.1.
6. The method of claim 1, wherein the solvent of the mixed solution is methanol, ethanol, isopropanol, dichloromethane or water.
7. The method for producing limonene hydroperoxide according to claim 1, wherein the mass ratio of the solvent to terpinolene in said mixed solution is 1-100.
8. The method according to claim 1, wherein the light source for providing light is selected from a halogen lamp, a xenon lamp, a mercury lamp, and an L ED lamp.
9. The method of claim 1, wherein the photochemical microchannel reactor comprises one or more fluidic modules connected in series, each fluidic module being illuminated by a light source; the depth of the internal channel of the photochemical microchannel reactor is 100 mu m-10 mm.
10. The method of claim 9, wherein the structure of the fluid module in the photochemical microchannel reactor is a microtubular structure, a channel-type structure, a T-type structure, a spherical structure, an umbrella-type structure, or a heart-type structure; the fluid module is made of special glass, silicon carbide, corrosion-resistant alloy or fluorine-containing polymer.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113045514A (en) * | 2021-03-31 | 2021-06-29 | 福州大学 | Method for preparing limonene epoxidation product |
| CN114621162A (en) * | 2022-04-01 | 2022-06-14 | 福州大学 | Co-oxidation preparation method of terpinene 4, 8-epoxide |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3505412A (en) * | 1965-11-13 | 1970-04-07 | Erich Klein | Preparation of terpinen-1-ol-(4) |
| US5620569A (en) * | 1993-12-23 | 1997-04-15 | Haarmann & Reimer Gmbh | Process for the photooxidation of terpene olefins |
| CN107848922A (en) * | 2015-05-08 | 2018-03-27 | 巴斯夫农业公司 | The preparation method of the alcohol of limonene 4 |
-
2020
- 2020-04-09 CN CN202010274601.7A patent/CN111393345A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3505412A (en) * | 1965-11-13 | 1970-04-07 | Erich Klein | Preparation of terpinen-1-ol-(4) |
| US5620569A (en) * | 1993-12-23 | 1997-04-15 | Haarmann & Reimer Gmbh | Process for the photooxidation of terpene olefins |
| CN107848922A (en) * | 2015-05-08 | 2018-03-27 | 巴斯夫农业公司 | The preparation method of the alcohol of limonene 4 |
Non-Patent Citations (1)
| Title |
|---|
| 张健 等: "微通道反应器在有机合成中的应用研究", 《广州化工》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113045514A (en) * | 2021-03-31 | 2021-06-29 | 福州大学 | Method for preparing limonene epoxidation product |
| CN114621162A (en) * | 2022-04-01 | 2022-06-14 | 福州大学 | Co-oxidation preparation method of terpinene 4, 8-epoxide |
| CN114621162B (en) * | 2022-04-01 | 2023-09-19 | 福州大学 | Co-oxidation preparation method of terpinene 4, 8-epoxide |
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