A method for treating wastewater containing 2,5-furandicarboxylic acid

Abstract

The present application discloses a method for treating wastewater containing 2,5-furandicarboxylic acid. The method utilizes oxygen free radicals formed by oxides to degrade 2,5-furandicarboxylic acid, and under neutral and mild conditions, 2,5-furandicarboxylic acid can be almost completely degraded. The present invention is particularly directed to low-concentration 2,5-furandicarboxylic acid wastewater, has high degradation efficiency, mild reaction conditions, and no acid-base secondary pollution problem, and has practical application value in the future in the treatment of wastewater containing 2,5-furandicarboxylic acid.

Description

Technical Field

[0001] The invention relates to a method for treating wastewater containing 2,5-furandicarboxylic acid, and belongs to the technical field of treating wastewater containing 2,5-furandicarboxylic acid. Background Art

[0002] The replacement of existing petroleum-based chemicals with carbon-neutral biomass chemicals is a future development trend. 2,5-Furandicarboxylic acid (FDCA) can be used in polymer materials such as polyester, polyurethane and polyamide due to its similar structure to terephthalic acid. It can be applied to industries such as engineering plastics, coatings, fibers, and packaging materials. With the development of the FDCA industry, wastewater containing a small amount of FDCA will be generated during the FDCA production process. In order to avoid environmental pollution, the FDCA in the wastewater needs to be treated. So far, there have been no reports on the treatment of wastewater containing FDCA. Therefore, the study of the degradation of FDCA in wastewater has certain practical application value for the development of the FDCA industry. Summary of the invention

[0003] According to one aspect of the present application, a method for treating wastewater containing 2,5-furandicarboxylic acid is provided, characterized in that the treatment steps are:

[0004] An oxygen free radical scavenger is added to the wastewater, the pH is adjusted, and then an oxide is added to the wastewater for reaction to obtain a treated solution.

[0005] Optionally, the pH is between 5-9;

[0006] Preferably, the pH is between 6-8.

[0007] Optionally, the oxygen free radical scavenger is selected from nitrogen oxides and benzoquinone substances;

[0008] Preferably, the oxygen free radical scavenger is selected from at least one of p-benzoquinone, tetramethylpiperidine nitrogen oxide, 4-hydroxy-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-acetylamino-2,2,6,6-tetramethylpiperidine nitrogen oxide, phenyl-N-tert-butylnitrone, and 1,1-diphenyl-2-picrylhydrazyl;

[0009] Optionally, the oxygen free radical scavenger is added in an amount of 1-150 ppm;

[0010] Preferably, the added amount is 10-100 ppm.

[0011] Free radical scavengers are used to capture oxygen in oxides, forming oxygen free radicals themselves. The oxygen free radicals decompose FDCA in the wastewater. This method accelerates the degradation rate of FDCA, improves the utilization rate of oxidants, and can efficiently degrade FDCA in the solution.

[0012] Optionally, the oxide is selected from at least one of tert-butyl peroxide, dichloroisocyanurate, trichloroisocyanuric acid, perchlorate, chlorate, hypochlorite and potassium permanganate;

[0013] Optionally, the amount of the oxide used is 10:(1-60) of the total amount of 2,5-furandicarboxylic acid;

[0014] Preferably, the amount of the oxide used is 5:(1-25) of the total amount of 2,5-furandicarboxylic acid.

[0015] Optionally, the total concentration of 2,5-furandicarboxylic acid in the wastewater is 0.1-6 g / kg;

[0016] Preferably, the total concentration is 0.5-1.5 g / kg.

[0017] According to the above aspects, the beneficial effects that can be produced by this application include:

[0018] 1) The method for treating wastewater containing 2,5-furandicarboxylic acid provided in the present application has the characteristics of mild reaction conditions, no need to introduce external energy, low requirements for treatment equipment, and is very suitable for industrial use;

[0019] 2) The method for treating wastewater containing 2,5-furandicarboxylic acid provided in the present application has a thorough decomposition effect and can decompose at least 93% of 2,5-furandicarboxylic acid in wastewater, and has a good industrial prospect. DETAILED DESCRIPTION

[0020] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0021] The FDCA degradation rate in the examples of the present application is calculated as follows:

[0022]

[0023] Example 1

[0024] Take 100 g of wastewater containing 1.0 g / L FDCA, add 0.001 g of tetramethylpiperidinium nitrogen oxide and 0.02 g of potassium bromide. After complete dissolution, adjust the pH of the solution to between 7.0 and 7.5, then add 1.7 g of 5% sodium hypochlorite aqueous solution, detect the FDCA concentration in the solution after 1 h of reaction, and calculate the FDCA degradation rate to be 96%.

[0025] Example 2

[0026] Take 100 g of wastewater containing 2.0 g / L FDCA, add 0.01 g p-benzoquinone, and after complete dissolution, adjust the solution pH to between 6.0 and 6.5, then add 0.3 g tert-butyl hydroperoxide, detect the FDCA concentration in the solution after 1 h of reaction, and calculate the FDCA degradation rate to be 99%.

[0027] Example 3

[0028] Take 100 g of wastewater containing 1.2 g / L of FDCA, add 0.005 g of 4-hydroxy-2,2,6,6-tetramethylpiperidinium nitrogen oxide, and after complete dissolution, adjust the pH of the solution to between 8.0 and 8.5, then add 0.5 g of trichloroisocyanuric acid, and detect the FDCA concentration in the solution after 1 h of reaction. The FDCA degradation rate is calculated to be 93%.

[0029] Example 4

[0030] Take 100 g of wastewater containing 0.7 g / L FDCA, add 0.001 g 1,1-diphenyl-2-picrylhydrazyl, and after complete dissolution, adjust the solution pH to between 6.0 and 6.5, then add 0.1 g potassium permanganate, detect the FDCA concentration in the solution after 1 h of reaction, and calculate the FDCA degradation rate to be 99.5%.

[0031] According to the implementation method provided in the present application, the optimal effect that can be produced is the 99.5% degradation rate described in Example 4.

[0032] It should be understood that the order of the various steps or the order in which a particular action is performed is not very important, as long as the teachings of the present invention remain operable. In addition, two or more steps or actions may be performed simultaneously.

[0033] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for treating wastewater containing 2,5-furandicarboxylic acid, characterized in that: The processing steps are: Adding an oxygen free radical scavenger to the wastewater, adjusting the pH, and then adding an oxide to the wastewater for reaction to obtain a treated solution; The total concentration of 2,5-furandicarboxylic acid in the wastewater is 0.1-6 g / kg; The oxygen free radical scavenger is selected from at least one of tetramethylpiperidinium N-oxide, 4-hydroxy-2,2,6,6-tetramethylpiperidinium N-oxide, and 1,1-diphenyl-2-picrylhydrazyl; The ratio of the amount of the oxide used to 2,5-furandicarboxylic acid is 10: 1 to 10: 60 by weight; The pH is between 5 and 9; The oxidizing agent is selected from at least one of tert-butyl peroxide, trichloroisocyanuric acid, perchlorate, chlorate, hypochlorite and potassium permanganate.

2. The processing method according to claim 1, characterized in that: The pH is between 6 and 8.

3. The processing method according to claim 1, characterized in that: The added amount of the oxygen free radical scavenger is 1-150 ppm.

4. The processing method according to claim 1, characterized in that: The added amount of the oxygen free radical scavenger is 10-100 ppm.

5. The processing method according to claim 1, characterized in that: The weight ratio of the oxide to 2,5-furandicarboxylic acid is 5:1 to 1:

5.

6. The processing method according to claim 1, characterized in that: The total concentration of 2,5-furandicarboxylic acid in the wastewater is 0.5-1.5 g / kg.

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