CN110882716B - Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis - Google Patents
Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis Download PDFInfo
- Publication number
- CN110882716B CN110882716B CN201910982463.5A CN201910982463A CN110882716B CN 110882716 B CN110882716 B CN 110882716B CN 201910982463 A CN201910982463 A CN 201910982463A CN 110882716 B CN110882716 B CN 110882716B
- Authority
- CN
- China
- Prior art keywords
- reaction
- solid acid
- acid catalyst
- catalyst
- valerolactone
- 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.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
- B01J29/405—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively containing rare earth elements, titanium, zirconium, hafnium, zinc, cadmium, mercury, gallium, indium, thallium, tin or lead
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/26—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member
- C07D307/30—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D307/32—Oxygen atoms
- C07D307/33—Oxygen atoms in position 2, the oxygen atom being in its keto or unsubstituted enol form
Abstract
The invention discloses a preparation method for converting biomass derived furfural into gamma-valerolactone by a novel solid acid catalyst through one-pot multi-step catalysis, which comprises the following steps: uniformly mixing a precursor generated by 0.3g-0.7g of zirconium nitrate with distilled water; adding a ZSM-5 carrier into the solution prepared in the last step; adding 6g-10g of urea for regulating the PH; heating the mixed solution to 95 ℃ and stirring vigorously for 5 hours; the solution was filtered, washed with distilled water and then dried at 90 ℃ for 14 hours; calcining the mixture in an oven at 550 ℃ for 4 hours; before the reaction, introducing nitrogen into the reaction kettle for discharging air in the kettle to keep the reaction environment in a nitrogen atmosphere; adding 20mL of solution formed by mixing isopropanol and water into a stainless steel high-pressure reaction kettle, adding furfural, a solid acid catalyst and a magnetic stirring rotor, and setting experimental conditions for reaction; after the reaction was completed, the reactor was placed in cold water to be rapidly cooled to room temperature, and the catalyst was recovered.
Description
Technical Field
The invention belongs to the field of preparation of acid catalysts, and relates to a novel multifunctional solid acid catalyst HZSM-5-ZrO2In particular to a preparation method for catalyzing furfural to be catalytically converted into gamma-valerolactone.
Background
The large-scale utilization of fossil resources has greatly promoted the development of human society and economy, while also causing many inevitable derivative problems including global warming, air pollution and energy shortage to improve environmental deterioration pollution and global energy crisis, and researchers have been gradually seeking to develop new green renewable resource utilization strategies in recent years. As a natural clean renewable energy source, has wide sources, abundant reserves and low price,biomass energy can be converted into various important high value-added fuels and chemicals, has great potential to replace traditional fossil energy, and the exploration of a more effective biomass resource utilization method is drawing extensive attention in academic and industrial circles. Gamma valerolactone has received much attention from researchers due to its excellent physical properties. The basic properties of gamma-valerolactone mainly include high boiling point, high flash point, low melting point, low toxicity and the like. The gamma-valerolactone can participate in various reactions, and is widely applied to the production of fuel additives, medical intermediates, high-grade olefin fuels, green regenerated solvents, nylon intermediates and the like. The reaction for preparing gamma-valerolactone from furfural involves two hydrolysis reactions and one hydrogenation reaction. At present, gamma-valerolactone is prepared from a biomass platform compound furfural, wherein hydrogen is mostly used as a hydrogen donor, liquid acid and a composite catalyst are mostly used as a catalyst, noble metal is introduced, and the like, so that the problems of poor safety, difficult recovery of the catalyst, high manufacturing cost and the like are caused. The invention uses molecular sieve ZSM-5 loaded ZrO2The single bifunctional solid acid catalyst is prepared and used in the reaction of converting furfural into gamma-valerolactone.
Disclosure of Invention
In order to solve the problems of the existing catalyst. The invention focuses on a novel single dual-function solid acid catalyst, and uses a molecular sieve to load non-noble metal oxide ZrO2The catalyst is synthesized by using a coprecipitation method, and the dried standby catalyst is white powder.
The invention adopts the following technical scheme that a preparation method for converting biomass derived furfural into gamma-valerolactone by using a novel solid acid catalyst through one-pot multi-step catalysis comprises the following steps:
1) uniformly mixing a precursor generated by 0.3g-0.7g of zirconium nitrate with distilled water;
2) adding a ZSM-5 carrier into the solution prepared in the previous step;
3) 6g-10g of urea is added for regulating PH;
4) heating the mixed solution to 95 ℃ and stirring vigorously for 5 hours;
5) the solution was filtered, washed with distilled water and then dried at 90 ℃ for 14 hours;
6) calcining the mixture in an oven at 550 ℃ for 4 hours;
7) before the reaction, introducing nitrogen into the reaction kettle for discharging air in the kettle to keep the reaction environment in a nitrogen atmosphere;
8) adding 20mL of solution formed by mixing isopropanol and water into a stainless steel high-pressure reaction kettle, adding furfural, a solid acid catalyst and a magnetic stirring rotor, and setting experimental conditions for reaction;
9) after the reaction was completed, the reactor was placed in cold water to be rapidly cooled to room temperature, and the catalyst was recovered to obtain a solution containing γ -valerolactone.
The silicon-aluminum ratio in the step 2) is 27.
In the step 3), the mass ratio of the urea to the ZSM-5 molecular sieve is 5-10g of molecular sieve to 1g of urea, and the pH is adjusted by heating and decomposing the urea to form ammonia water, so that the pH is controlled to be 9-11.6.
The precursor containing Zr ions in an equimolar amount is generated from the zirconium nitrate in the step 2).
In the step 8), isopropanol and water are mutually soluble in any proportion.
The amount of the catalyst in the step 8) is controlled to be between 0.15g and 0.6 g.
The metal loading amount in the step 2) is controlled to be 5-20 wt%.
The reaction temperature of the step 8) is controlled at 125-200 ℃.
The reaction time of the step 8) is controlled to be 16-22 h.
And in the step 8), the solid acid catalyst HZSM-5-ZrO2 can be recycled.
The experimental method comprises the following steps:
1. adding 20mL of solution formed by mixing isopropanol and water into a stainless steel high-pressure reaction kettle, adding furfural, a solid acid catalyst and a magnetic stirring rotor, and setting four-level orthogonal experiments of five factors (metal load, catalyst dosage, reaction temperature, reaction time and isopropanol dosage).
2. Before the reaction, nitrogen is introduced into the reaction kettle to exhaust air in the kettle, so that the reaction environment is kept in a nitrogen atmosphere. And screwing down screws of the reaction kettle to keep a closed environment in the kettle, connecting the reaction kettle with a power supply and a temperature sensor, setting the temperature and the reaction time of the reaction kettle, keeping the stirring speed of the magnetons at 500 revolutions per minute, and starting the reaction.
3. After completion of the reaction, the reactor was placed in cold water to be rapidly cooled to room temperature. The catalyst was recovered and a solution containing gamma valerolactone was obtained and awaited testing.
And (3) a product detection method:
1. the furfural and gamma-valerolactone concentrations of the filtrate were determined using a Bio-Rad Aminex HPX-87H column at 65 ℃ using high performance liquid chromatography and a refractive index detector.
2. As a mobile phase, 5mM sulfuric acid aqueous solution was used at a flow rate of 0.6 mL/min.
3. And preparing standard samples with different concentration gradients for fitting standard curves of furfural and gamma-valerolactone.
4. And (5) detecting a product, and calculating the concentration and the yield of the gamma-valerolactone according to the peak area.
Drawings
Fig. 1 is a result based on experimental condition nine in the table.
In the figure: 0.2mL furfural, 15 wt% Zr, 0.4g catalyst, 17.4mL isopropanol, 175 deg.C, 16 hours; only one variable was changed to obtain new reaction conditions and yields.
Detailed Description
The invention is further described below with reference to the following figures and specific examples.
A 20mL solution composed of a furfural and isopropanol mixed solution was added to a high-pressure reaction kettle together with a catalyst, a solid acid catalyst and a magnetic stirring rotor were added, and four-level orthogonal experiments were performed with five factors (metal loading, catalyst amount, reaction temperature, reaction time, and isopropanol addition) as shown in table 1 below. Before the reaction, nitrogen is introduced into the reaction kettle to exhaust air in the kettle, so that the reaction environment is kept in a nitrogen atmosphere. And screwing down screws of the reaction kettle to keep a closed environment in the kettle, connecting the reaction kettle with a power supply and a temperature sensor, setting the temperature and the reaction time of the reaction kettle, keeping the stirring speed of the magnetons at 500 revolutions per minute, and starting the reaction. After completion of the reaction, the reactor was placed in cold water to be rapidly cooled to room temperature. The catalyst was recovered and a solution containing gamma valerolactone was obtained and awaited for testing. The furfural and gamma-valerolactone concentrations of the filtrate were determined using a Bio-Rad Aminex HPX-87H column at 65 ℃ using high performance liquid chromatography and a refractive index detector. Testing a product by using a high performance liquid chromatography, firstly preparing 0.05mol/L dilute sulfuric acid solution as a mobile phase, and putting the prepared dilute sulfuric acid solution into a volumetric flask; pouring dilute sulfuric acid into a beaker, placing the beaker into an ultrasonic oscillator, oscillating for 30 minutes, and filtering the solution after oscillation by using a filter membrane to remove bubbles in a mobile phase; opening a high performance liquid chromatography baseline according to an operation program; the flow rate of the mobile phase is controlled to be 0.6 mL/min; and when the base line tends to be stable, injecting by using a sample injection needle, and calculating the concentration and the gamma-valerolactone yield according to the peak area.
Zr can be used as metal with the function of promoting dehydrogenation of hydrogen donor, ZrO2 and CuO or SnO loaded by molecular sieve2Compared with the prior art, the Zr/ZSM-5 catalyst has obvious catalytic effect, is considered to have the effect of catalyzing furfural to produce gamma-valerolactone, and can complete MPV reaction and acid hydrolysis reaction which are connected in series in the process. The results in table 1 show that different reaction conditions have a large effect on the yield of gamma-valerolactone, and the catalytic performance is best when the metal loading reaches 15%. Under the conditions of the ninth group (metal loading 15 wt%, catalyst addition 0.4, reaction temperature 175 deg.C, reaction time 16 hours, isopropanol amount 17.4ml) in the table, the yield of gamma-valerolactone reached 49.71%. The possible reasons are that the Zr/ZSM-5 catalyst has proper Bronsted acid sites and Lewis acid sites, the proportion and the number of the B acid sites and the L acid sites are proper, and the catalysis conditions are proper, so that the reaction can be performed more fully.
Table 1: reaction conditions of Zr/ZSM-5
(a: IPA volume in 20ml solution)
And then, the catalytic effect of the novel multifunctional solid acid catalyst HZSM-5-ZrO2 is optimized in detail.
Reaction conditions suitable for gamma-valerolactone production were further investigated by using a Zr/ZSM-5 catalyst to obtain higher gamma-valerolactone yield, and 10 sets of univariate reactions were continued on the basis of the experimental conditions of set 9 in Table 1 (metal loading 15% wt, catalyst addition 0.4g, reaction temperature 175 ℃, reaction time 16 hours, isopropanol amount 17.4 ml). For example, two sets of reactions for the first univariate correspond to reaction conditions of: 0.2mL of furfural, 10 wt% of Zr or 20 wt% of Zr, 0.4g of catalyst, 17.4mL of isopropanol, 175 ℃ and 16h, wherein the changed conditions are only the change of metal loading, and the change rule of the subsequent experimental conditions is the same as that of the first group. At this time, the yield of gamma-valerolactone was significantly improved, and the yield of most GVL reached 40% or more. It is evident from the figure that the metal loading of Zr on the molecular sieve plays a crucial role in FAL conversion and GVL production, and the effect is significantly reduced for the high metal loading catalyst. The possible reasons are that the loading of the metal on the molecular sieve support has reached saturation, and at this time, if the loading is continuously increased, the pores of the molecular sieve are blocked, the acidity of the molecular sieve is obviously reduced, and the specific surface area of the whole catalyst is reduced, so that the catalytic performance is reduced. In addition, variations in reaction temperature and reaction time had a moderate effect on GVL yield, with the temperature controlled at 165 ℃ and 185 ℃, with minor variations in gamma valerolactone yield. Extending the time from 14 hours to 18 hours, the gamma valerolactone yield increased, thus driving the reaction toward forward progress as the reaction time increased. The amount of catalyst and the amount of IPA had a small effect, indicating that the amount of catalyst added, 0.3g and the amount of IPA used, 18.5ml, had satisfied the conditions required for the reaction under these conditions. By optimizing the Zr/ZSM-5 catalytic conditions, the yield of GVL reached a maximum of 52.43% at 175 ℃ for 18 hours using 0.4g of 15 wt% Zr/ZSM-5 as catalyst and 17.4mL of isopropanol as hydrogen donor.
Claims (10)
1. The method for converting biomass derived furfural into gamma-valerolactone by using the solid acid catalyst through one-pot multi-step catalysis is characterized by comprising the following steps of:
1) uniformly mixing a precursor generated by 0.3g-0.7g of zirconium nitrate with distilled water;
2) adding a ZSM-5 carrier into the solution prepared in the last step;
3) adding 6g-10g of urea for adjusting the pH value;
4) heating the mixed solution to 95 ℃ and stirring vigorously for 5 hours;
5) the solution was filtered, washed with distilled water and then dried at 90 ℃ for 14 hours;
6) calcining for 4 hours in an oven at 550 ℃ to obtain a solid acid catalyst;
7) before the reaction, introducing nitrogen into the reaction kettle for discharging air in the kettle to keep the reaction environment in a nitrogen atmosphere;
8) adding 20mL of solution formed by mixing isopropanol and water into a stainless steel high-pressure reaction kettle, adding furfural, a solid acid catalyst and a magnetic stirring rotor, and setting experimental conditions for reaction;
9) after the reaction is finished, placing the reactor in cold water to be rapidly cooled to room temperature, and recovering the catalyst to obtain a solution containing gamma-valerolactone;
the solid acid catalyst is HZSM-5-ZrO2 。
2. The method of claim 1, wherein the ZSM-5 in step 2) has a silica to alumina ratio of 27.
3. The method as claimed in claim 1, wherein the mass ratio of urea to ZSM-5 molecular sieve in step 3) is 5-10g molecular sieve to 1g urea, and the pH is adjusted by heating urea to decompose into ammonia water, thereby controlling the pH to be 9-11.6.
4. The method of claim 1, wherein the zirconium nitrate is generated as a precursor containing Zr ions in an equimolar amount in step 2).
5. The method of claim 1, wherein the isopropanol is miscible with water in any ratio in step 8).
6. The method as claimed in claim 1, wherein the amount of the catalyst used in the step 8) is controlled to be between 0.15g and 0.6 g.
7. The process of claim 1 wherein the metal loading of step 2) is controlled to be in the range of 5 wt% to 20 wt%.
8. The method as claimed in claim 1, wherein the reaction temperature in step 8) is controlled at 125-200 ℃.
9. The method as claimed in claim 1, wherein the reaction time of step 8) is controlled to 16-22 h.
10. The method of claim 1, wherein the solid acid catalyst is HZSM-5-ZrO2 And recycling the recovered product.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910982463.5A CN110882716B (en) | 2019-10-16 | 2019-10-16 | Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910982463.5A CN110882716B (en) | 2019-10-16 | 2019-10-16 | Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110882716A CN110882716A (en) | 2020-03-17 |
| CN110882716B true CN110882716B (en) | 2022-06-17 |
Family
ID=69746196
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910982463.5A Active CN110882716B (en) | 2019-10-16 | 2019-10-16 | Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110882716B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113831308A (en) * | 2020-06-24 | 2021-12-24 | 中国石油化工股份有限公司 | Method for preparing gamma-valerolactone by catalytic conversion of furfural by one-pot method |
| CN114656442B (en) * | 2022-04-15 | 2023-04-11 | 北京大学 | Method for preparing caprolactone from 5-hydroxymethyl furoic acid |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1164509A (en) * | 1996-05-08 | 1997-11-12 | 中国科学院大连化学物理研究所 | Molecular sieve type ultrastrong acid and its preparing method |
| CN104230615A (en) * | 2014-08-25 | 2014-12-24 | 南京林业大学 | Method for preparing aromatic hydrocarbon and cyclopentenone from biomass derivative gamma-valerolactone by catalytic conversion |
| CN106807436A (en) * | 2017-01-25 | 2017-06-09 | 东南大学 | A kind of preparation method of the acid base catalysators of microwave modification Ca Zr/H ZSM 5 |
| CN110003010A (en) * | 2019-03-29 | 2019-07-12 | 昆明理工大学 | A kind of direct method for preparing levulinate using xylose |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8962867B2 (en) * | 2011-05-25 | 2015-02-24 | Wisconsin Alumni Research Foundation | Solute-enhanced production of gamma-valerolactone (GVL) from aqueous solutions of levulinic acid |
-
2019
- 2019-10-16 CN CN201910982463.5A patent/CN110882716B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1164509A (en) * | 1996-05-08 | 1997-11-12 | 中国科学院大连化学物理研究所 | Molecular sieve type ultrastrong acid and its preparing method |
| CN104230615A (en) * | 2014-08-25 | 2014-12-24 | 南京林业大学 | Method for preparing aromatic hydrocarbon and cyclopentenone from biomass derivative gamma-valerolactone by catalytic conversion |
| CN106807436A (en) * | 2017-01-25 | 2017-06-09 | 东南大学 | A kind of preparation method of the acid base catalysators of microwave modification Ca Zr/H ZSM 5 |
| CN110003010A (en) * | 2019-03-29 | 2019-07-12 | 昆明理工大学 | A kind of direct method for preparing levulinate using xylose |
Non-Patent Citations (3)
| Title |
|---|
| Juan A. Melero et al..Rational Optimization of Reaction Conditions for the One-Pot Transformation of Furfural to γ-Valerolactone over Zr-Al-Beta Zeolite：Toward the Efficient Utilization of Biomass.《Ind. Eng. Chem. Res.》.2018,第57卷 * |
| 刘治华等.Zr改性对HZSM-5分子筛催化甲醇制丙烯反应性能的影响.《石油化工》.2015,第44卷(第5期), * |
| 肖容华等.复合纳米固体超强酸SO4(2-)/ZrO2-ZSM-5的制备及应用研究.《广州化工》.2009,第37卷(第5期), * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110882716A (en) | 2020-03-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110882716B (en) | Preparation method for converting biomass derived furfural into gamma-valerolactone by solid acid catalyst one-pot multi-step catalysis | |
| US10898888B2 (en) | Preparation and application of magnetic metallic oxide cross-linked acidic polyionic liquid | |
| CN104277020B (en) | Aqueous catalysis 5 hydroxymethyl furfural prepares the method for 2,5-furandicarboxylic acid | |
| CN111875566A (en) | Method for preparing 2, 5-dimethylfuran | |
| CN108892652B (en) | Method for preparing dimethyl 2, 5-furandicarboxylate | |
| CN103521256B (en) | Molecular sieve catalyst for catalyzing and dehydrating glycerin to prepare acraldehyde and preparation method of molecular sieve catalyst | |
| CN102417493B (en) | Method for preparing catalysts | |
| CN104801337A (en) | Ethanol catalyst prepared from synthesis gas and dimethyl ether with one-step method as well as preparation method of ethanol catalyst | |
| CN106944050B (en) | A kind of catalyst and its preparation method and application synthesizing 1,3- propylene glycol | |
| CN108640892A (en) | A kind of synthetic method of 5 hydroxymethyl furfural | |
| CN102649057B (en) | Catalyst for preparing oxalate through coupling reaction of CO (carbon monoxide) | |
| CN106831391A (en) | The method that chemicals is prepared by microalgae Direct Hydrothermal oxidation | |
| CN109867641A (en) | Utilize the method for Ce-Mo composite oxide catalytic fructose preparation 2,5-furandaldehyde | |
| CN102258994B (en) | Method for preparing catalyst used in synthesizing isophorone through acetone multiphase method | |
| CN113145113A (en) | Carbon dioxide hydrogenation catalyst, preparation method and application thereof | |
| CN111054342B (en) | Catalyst for preparing glycol from carbohydrate and preparation method thereof | |
| CN107737596B (en) | Preparation method and application of active carbon loaded Cu and Al co-modified platinum-tungsten catalyst | |
| CN111793218A (en) | Preparation method and application of Schiff base dicarboxylic acid ligand Zn and Cu metal organic framework material | |
| CN115536495B (en) | Method for preparing 1, 4-pentanediol | |
| CN102649729A (en) | Method for producing oxalate through CO gas phase coupled catalytic reaction | |
| CN115181007B (en) | Method for generating polyalcohol and alkane by hydrogenation ring-opening conversion of furyl derivative | |
| CN111939918B (en) | Rare earth oxide/copper oxide-zirconium oxide catalyst, preparation method thereof and method for preparing lactic acid from glycerol | |
| CN109320419A (en) | A kind of method of biomass-based furfural carbonate synthesis dialkyl | |
| CN102649728B (en) | Method for producing oxalate through gas-phase reaction of carbon monoxide | |
| CN113582952B (en) | Method for preparing 2, 5-furandicarboxylic acid by using straw |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |