A method for treating high-concentration formaldehyde wastewater by by-product rubber 234 of triacetoneamine

Abstract

The present invention discloses a method for treating high-concentration formaldehyde wastewater with by-product rubber 234 of triacetoneamine. Under the conditions of the presence of by-product rubber 234 of triacetoneamine, high-concentration formaldehyde wastewater, and dilute alkali, by controlling the reaction temperature and adjusting an appropriate feeding ratio, the formaldehyde concentration can be reduced, and the removal rate can reach over 99.5%. The present invention uses by-product rubber 234 of triacetoneamine to remove high-concentration formaldehyde. Since rubber 234 is an oil and insoluble in water, while removing high-concentration formaldehyde, the COD decomposed by formaldehyde can also be extracted, thereby reducing the COD.

Description

Technical Field

[0001] The invention belongs to the field of polymer material wastewater treatment, and specifically relates to a method for treating high-concentration formaldehyde wastewater using triacetoneamine by-product rubber 234. Background Art

[0002] Formaldehyde is a common chemical raw material, widely used in medicine, pesticides and other fields for material synthesis and preparation, which results in the production of a large amount of formaldehyde-containing wastewater. The World Health Organization has assessed that formaldehyde is highly toxic and has teratogenic and carcinogenic effects on organisms. Therefore, formaldehyde wastewater from various industries must be treated to meet the standards before it can be discharged. At present, the acid-base condensation method, advanced oxidation method and biological method are mainly used for formaldehyde wastewater at home and abroad. Among them, the acid-base condensation method is often used to treat high-concentration formaldehyde wastewater, which can remove more than about 98% of formaldehyde, but this method will not only produce a large amount of solid waste, significantly increase investment costs, but also have high operating costs; the advanced oxidation method can effectively degrade formaldehyde in wastewater by using the strong oxidizing property of the substance, and has the advantages of rapid reaction and no secondary pollution, but is often suitable for low-concentration formaldehyde wastewater treatment, and has the disadvantages of high investment cost and fast equipment update; and the biochemical method alone is difficult to meet the discharge requirements of wastewater, and usually needs to be used in combination with other technologies, because formaldehyde has a great toxic effect on microorganisms, and a general concentration of 100~200mg / L can inhibit microorganisms. Therefore, before entering the biochemical treatment, the formaldehyde in the wastewater must be pretreated to meet the biochemical water inlet requirements; the above-mentioned methods cannot be used in large-scale engineering applications in treating formaldehyde wastewater. Summary of the invention

[0003] In order to solve the above problems, the present invention discloses a method for treating high-concentration formaldehyde wastewater by using triacetoneamine as a by-product rubber 234.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] A method for treating high-concentration formaldehyde wastewater using triacetoneamine by-product rubber 234, wherein the structural formula of the rubber 234 is as follows:

[0006] , wherein n is the number of repeating units, also known as the degree of polymerization of the polymer, and the abbreviation of the triacetoneamine by-product rubber 234 is .

[0007] A method for treating high-concentration formaldehyde wastewater with triacetoneamine by-product rubber 234, the reaction principle is as follows:

[0008] .

[0009] A method for treating high-concentration formaldehyde wastewater using triacetoneamine by-product rubber 234, the method comprising the following specific steps:

[0010] Using rubber 234, high-concentration formaldehyde wastewater, and a small amount of caustic soda as raw materials, heat to a certain temperature, keep the temperature for reaction, adjust the pH of the system, adjust the appropriate feeding ratio, react for 2 - 3 hours. After the reaction is completed, let it stand for stratification. The oil layer is the treated rubber 234 and can directly enter the incinerator for incineration. The water layer is the water with formaldehyde and COD removed and enters the sewage treatment station for unified treatment, so that this formaldehyde wastewater removes formaldehyde and also removes the generated COD.

[0011] Furthermore, the mass ratio of the rubber 234 to the high-concentration formaldehyde wastewater is 2:1 - 3:1.

[0012] Furthermore, the indexes of the high-concentration formaldehyde wastewater are: formaldehyde concentration 130000 - 180000 mg / L, COD 80000 - 100000 mg / L.

[0013] Furthermore, the mass ratio of the high-concentration formaldehyde wastewater to the caustic soda is 1:0.002 - 0.003.

[0014] Furthermore, the pH of the system is 10 - 11.

[0015] Furthermore, the reaction temperature of the system is 80 - 90 °C.

[0016] The beneficial effects of the present invention are:

[0017] The invention discloses a method for treating high-concentration formaldehyde wastewater with by-product rubber 234 of triacetoneamine. The purpose is to synthesize the formaldehyde wastewater generated by using paraformaldehyde in the methylation synthesis step of the light stabilizer. The generated wastewater has a high formaldehyde concentration and a high COD. And a large amount of by-product rubber 234 generated in the synthesis of triacetoneamine is also incinerated as fuel in the later stage. Through research, it is found that the by-product rubber 234 of triacetoneamine is a polymer containing carbonyl groups and can undergo aldol condensation reaction with formaldehyde, which can effectively treat high-concentration formaldehyde wastewater and can absorb the COD in the formaldehyde wastewater, using the by-product to treat the difficult-to-treat high-concentration industrial wastewater; not only greatly reducing the cost, but also achieving clean production, providing a guarantee for industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the GC-MS spectrum of the rubber 234 described in the present invention;

[0019] Figure 2 It is the NMR spectrum of the rubber 234 described in the present invention;

[0020] Figure 3 It is the IR spectrum of the rubber 234 described in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention will be further illustrated below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and not to limit the scope of the present invention.

[0022] Example 1:

[0023] Put 300 g of rubber 234 and 100 g of high-concentration formaldehyde wastewater (formaldehyde concentration 146,013 mg / L, COD 91,032 mg / L) into a four-neck reaction flask, stir at room temperature, add 0.3 g of flake soda to adjust the pH to 10, slowly heat up to 80 °C, stir and keep the temperature for 2 hours, then let it stand for stratification. The upper layer is the rubber 234 oil layer with a measured calorific value of 8,522 kJ / kg and a moisture content of 6.1%, which is used as fuel. The lower layer is the water layer with a measured formaldehyde concentration of 30 mg / L and a COD of 8,534 mg / L. The formaldehyde removal rate is 99.9%, and the COD removal rate is 90.6%.

[0024] Example 2:

[0025] Put 600 g of rubber 234 and 300 g of high-concentration formaldehyde wastewater (formaldehyde concentration 131,055 mg / L, COD 85,002 mg / L) into a four-neck reaction flask, stir at room temperature, add 0.6 g of flake soda to adjust the pH = 10, slowly heat up to 80 °C, stir and keep the temperature for 2 hours, then let it stand for stratification. The upper layer is the rubber 234 oil layer with a measured calorific value of 8,612 kJ / kg and a moisture content of 5.3%, which is used as fuel. The lower layer is the water layer with a measured formaldehyde concentration of 366 mg / L and a COD of 9,915 mg / L. The formaldehyde removal rate is 99.7%, and the COD removal rate is 88.3%.

[0026] Example 3:

[0027] Put 1,000 g of rubber 234 and 500 g of high-concentration formaldehyde wastewater (formaldehyde concentration 131,055 mg / L, COD 85,002 mg / L) into a four-neck reaction flask, stir at room temperature, add 1.2 g of flake soda to adjust the pH = 11, slowly heat up to 85 °C, stir and keep the temperature for 3 hours, then let it stand for stratification. The upper layer is the rubber 234 oil layer with a measured calorific value of 8,219 kJ / kg and a moisture content of 6.5%, which is used as fuel. The lower layer is the water layer with a measured formaldehyde concentration of 297 mg / L and a COD of 9,530 mg / L. The formaldehyde removal rate is 99.7%, and the COD removal rate is 88.7%.

[0028] Example 4:

[0029] Put 1125 g of rubber 234 and 350 g of high-concentration formaldehyde wastewater (formaldehyde concentration 131055 mg / L, COD 85002 mg / L) into a four-neck reaction flask, stir at room temperature, add 1 g of sodium hydroxide flakes to adjust the pH to 11, slowly heat up to 85 °C, stir and keep the temperature for reaction for 2.5 hours, then let it stand for stratification. The upper layer is the rubber 234 oil layer with a calorific value of 8712 kj / kg and a moisture content of 4.6%, which is used as fuel. The lower layer is the water layer with a formaldehyde concentration of 27 mg / L and a COD of 6990 mg / L. The formaldehyde removal rate is 99.9% and the COD removal rate is 91.7%. The detection results of the removal rates of Examples 1-4 are shown in Table 1 below.

[0030]

[0031] It should be noted that the above content only illustrates the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. For those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and retouches can be made, and these improvements and retouches all fall within the protection scope of the claims of the present invention.

Claims

1. A method for treating high-concentration formaldehyde wastewater by using by-product rubber 234 of triacetoneamine, characterized in that, The structural formula of the rubber 234 is as follows: , where n is the number of repeating units; The method comprises the following steps: using rubber 234, high-concentration formaldehyde wastewater, and caustic soda as raw materials, heating to 80-90 °C, holding for reaction, adjusting the pH of the system to 10-11, adjusting an appropriate feeding ratio, the mass ratio of the rubber 234 to the high-concentration formaldehyde wastewater being 2:1-3:1, reacting for 2-3 h. After the reaction is completed, standing for stratification, the oil layer is the treated rubber 234 which can directly enter the incinerator for incineration, and the water layer is the water with formaldehyde and COD removed, which enters the sewage treatment station for unified treatment.

2. The method for treating high-concentration formaldehyde wastewater by using by-product rubber 234 of triacetoneamine as claimed in claim 1, wherein, The reaction principle is as follows: 。 3. The method for treating high-concentration formaldehyde wastewater by using by-product rubber 234 of triacetoneamine as claimed in claim 2, wherein: The mass ratio of the high-concentration formaldehyde wastewater to the caustic soda is 1:0.002-0.

003.

4. The method for treating high-concentration formaldehyde wastewater by using by-product rubber 234 of triacetoneamine according to claim 2, wherein: The holding reaction time is 2-3 h.

5. The method for treating high-concentration formaldehyde wastewater with rubber 234 by-product of triacetoneamine as described in claim 2, characterized in that: The indexes of the high-concentration formaldehyde wastewater are that the formaldehyde concentration is 130,000-180,000 mg / L and the COD is 80,000-100,000 mg / L.

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