阅读说明：本技术 一种催化氧化法去除废水中甲醛的方法 (Method for removing formaldehyde in wastewater by catalytic oxidation method ) 是由 马庆国 牛宇岚 薛彦峰 郝钰 于 2021-07-14 设计创作，主要内容包括：本发明涉及一种催化氧化法去除废水中甲醛的方法,属于废水处理技术领域。以过渡金属氧化物为催化剂,以过氧化氢溶液为氧化试剂,于25-45℃下搅拌反应15-60min,将甲醛催化氧化为二氧化碳和水。其中,过渡金属氧化物选自Fe-(2)O-(3)、Co-(2)O-(3)、NiO、CuO和ZnO中的任一种。以该方法能够有效去除废水中的甲醛,催化剂易回收且可重复使用,过量的过氧化氢会分解为水和氧气,对环境友好、安全无毒。(The invention relates to a method for removing formaldehyde in wastewater by a catalytic oxidation method, belonging to the technical field of wastewater treatment. Taking transition metal oxide as a catalyst and hydrogen peroxide solution as an oxidizing agent, stirring and reacting for 15-60min at 25-45 ℃, and catalytically oxidizing formaldehyde into carbon dioxide and water. Wherein the transition metal oxide is selected from Fe 2 O 3 、Co 2 O 3 NiO, CuO and ZnO. The method can effectively remove formaldehyde in the wastewater, the catalyst is easy to recover and can be reused, and excessive hydrogen peroxide can be decomposed into water and oxygen, so that the method is environment-friendly, safe and nontoxic.)

1. A method for removing formaldehyde in wastewater by a catalytic oxidation method is characterized in that the formaldehyde-containing wastewater is sequentially treated withAdding transition metal oxide and hydrogen peroxide solution, and removing formaldehyde in the wastewater by catalytic oxidation, wherein the transition metal oxide is selected from Fe₂O₃、Co₂O₃NiO, CuO and ZnO.

2. The method as claimed in claim 1, wherein the concentration of formaldehyde in the wastewater containing formaldehyde is 200-1000 mg/L.

3. The process of claim 1, wherein the transition metal oxide is added in an amount to give a final concentration of 0.4 to 1.5 wt% of the transition metal oxide in the wastewater.

4. The method as claimed in claim 1, wherein the concentration of hydrogen peroxide in the hydrogen peroxide solution is 30 wt%, and the amount of hydrogen peroxide is 0.5-3 wt% based on the final concentration of hydrogen peroxide in the wastewater.

5. The method for removing formaldehyde from wastewater by catalytic oxidation according to claim 1, wherein the reaction temperature is 25-45 ℃.

6. The method for removing formaldehyde from wastewater by using the catalytic oxidation method as claimed in claim 1, wherein the reaction time is 15-60 min.

Technical Field

The invention relates to a method for removing formaldehyde in wastewater, in particular to a method for removing formaldehyde in wastewater through catalytic oxidation reaction, belonging to the technical field of wastewater treatment.

Background

Formaldehyde is an important industrial raw material, is widely applied to the industries of medicine, cotton textile, chemical industry and the like, and discharges a large amount of waste gas and waste liquid when producing related products, so that the air quality is seriously reduced, water resources are polluted, the human health is seriously influenced, and the environment is also polluted. The formaldehyde has strong biological toxicity, is determined as carcinogenic and teratogenic substances by the world health organization, and can cause symptoms such as dizziness, nausea, immunologic function reduction, memory reduction, inappetence and the like if a human body is in the air containing high-concentration formaldehyde for a long time, and can also cause death seriously.

At present, the formaldehyde treatment method comprises the following steps: physical, chemical, and biochemical methods, and the like. The physical method mainly takes porous particles as an adsorbent to adsorb and enrich formaldehyde, the adsorbent in the wastewater is easy to reach adsorption saturation and lose efficacy, the adsorbent is difficult to recycle, and the formaldehyde is not degraded fundamentally. The chemical method mainly converts formaldehyde into other nontoxic or low-toxic substances through oxidation reaction so as to achieve the aim of removing formaldehyde, and the oxidation method adopted at present has the defects of large oxygen consumption, difficult catalyst recovery, easy catalyst failure and the like. The biochemical method adopts microorganisms with strong metabolism, has high efficiency and does not produce secondary pollution, but the microorganisms are sensitive to temperature and pH value of wastewater environment, so that specific microbial strains need to be cultured and propagated for formaldehyde wastewater in different chemical environments, and a large amount of manpower and material resources are consumed. Therefore, an environment-friendly and efficient method for removing formaldehyde is urgently needed.

Disclosure of Invention

The invention aims to provide a method for removing formaldehyde in wastewater through catalytic oxidation reaction.

The technical solution for realizing the purpose of the invention is as follows: a method for removing formaldehyde in wastewater by catalytic oxidation comprises sequentially adding transition metal oxide and hydrogen peroxide solution into wastewater containing formaldehyde, and reacting at 25-45 deg.C under stirring for 15-60 min.

The concentration of the formaldehyde in the wastewater is 200-1000 mg/L.

The transition metal oxide is selected from Fe₂O₃、Co₂O₃NiO, CuO and ZnO.

The mass of the transition metal oxide is that the final concentration of the transition metal oxide in the wastewater is 0.4-1.5 wt%.

The concentration of the hydrogen peroxide in the hydrogen peroxide solution is 30 wt%, and the hydrogen peroxide solution is added until the final concentration of the hydrogen peroxide in the wastewater is 0.5-3 wt%.

The reaction temperature is 25-45 ℃.

The reaction time is 15-60 min.

The invention has the beneficial effects that: the invention provides a method for removing formaldehyde in wastewater by a catalytic oxidation method. Under the condition of knowing the concentration of formaldehyde in the wastewater, the formaldehyde can be completely oxidized by controlling the type and the dosage of the transition metal oxide and the concentration of the hydrogen peroxide in the wastewater under the condition of using less catalysts and oxidants, so that the formaldehyde is converted into carbon dioxide and water, the formaldehyde is recovered by centrifugation or filtration after use, the catalytic activity of the recovered catalyst is unchanged, other auxiliaries are not required to be added in the process, and the method has a better industrial application prospect. The method can effectively remove formaldehyde in the wastewater, avoids secondary pollution to the environment caused by easy failure and difficult recovery of the catalyst in the prior art, is environment-friendly, safe and nontoxic.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Example 1

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, and then sequentially adding Fe₂O₃And a hydrogen peroxide solution having a concentration of 30 wt% to Fe in the above wastewater₂O₃Was 1.2% by weight and hydrogen peroxide was 0.8% by weight, and the reaction was stirred at 45 ℃ for 60 minutes and then subjected to liquid chromatography analysis, whereby the conversion of formaldehyde was found to be 46.5%.

Example 2

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, and then sequentially adding Co₂O₃And 30 wt% hydrogen peroxide solution to Co in the wastewater₂O₃Was 1.2% by weight and hydrogen peroxide was 0.8% by weight, and the reaction was stirred at 45 ℃ for 60 minutes and then subjected to liquid chromatography analysis, whereby the conversion of formaldehyde was found to be 36.7%.

Example 3

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding NiO and hydrogen peroxide solution with concentration of 30 wt% until the final concentration of NiO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, stirring and reacting for 60min at 45 ℃, and then carrying out liquid chromatography analysis to determine that the formaldehyde conversion rate is 62.1%.

Example 4

Wastewater with formaldehyde concentration of 1000mg/L is added into a 100mL three-neck flask, then CuO and hydrogen peroxide solution with concentration of 30 wt% are sequentially added until the final concentration of CuO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, the mixture is stirred and reacted for 60min at 45 ℃, and then liquid chromatography analysis is carried out, and the conversion rate of formaldehyde is 84.6%.

Example 5

Wastewater with formaldehyde concentration of 1000mg/L is added into a 100mL three-neck flask, ZnO and hydrogen peroxide solution with concentration of 30 wt% are sequentially added until the final concentration of ZnO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, the mixture is stirred and reacted for 60min at 45 ℃, and then liquid chromatography analysis is carried out, and the formaldehyde conversion rate is 43.4%.

Example 6

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding CuO and a hydrogen peroxide solution with concentration of 30 wt% until the final concentration of CuO in the wastewater is 0.4 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, stirring and reacting for 15min at 25 ℃, and then carrying out liquid chromatography analysis to obtain that the formaldehyde conversion rate is 92.9%.

Example 7

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding CuO and a hydrogen peroxide solution with concentration of 30 wt% until the final concentration of CuO in the wastewater is 1.5 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, stirring and reacting for 15min at 25 ℃, and then carrying out liquid chromatography analysis to obtain the formaldehyde conversion rate of 88.4%.

Example 8

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding CuO and a hydrogen peroxide solution with concentration of 30 wt% until the final concentration of CuO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.5 wt%, stirring and reacting for 15min at 25 ℃, and then carrying out liquid chromatography analysis to obtain the formaldehyde conversion rate of 88.2%.

Example 9

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding CuO and a hydrogen peroxide solution with concentration of 30 wt% until the final concentration of CuO in the wastewater is 1.1 wt% and the final concentration of hydrogen peroxide is 3 wt%, stirring and reacting for 15min at 25 ℃, and then carrying out liquid chromatography analysis to determine that the formaldehyde conversion rate is 96.6%.

Example 10

Wastewater with formaldehyde concentration of 200mg/L is added into a 100mL three-neck flask, then CuO and hydrogen peroxide solution with concentration of 30 wt% are sequentially added until the final concentration of CuO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, the mixture is stirred and reacted for 15min at 45 ℃, and then liquid chromatography analysis is carried out, and the formaldehyde conversion rate is 85.1%.

Example 11

Adding wastewater with formaldehyde concentration of 1000mg/L into a 100mL three-neck flask, then sequentially adding CuO and a hydrogen peroxide solution with concentration of 30 wt% until the final concentration of CuO in the wastewater is 1.2 wt% and the final concentration of hydrogen peroxide is 0.8 wt%, stirring and reacting for 15min at 25 ℃, and then carrying out liquid chromatography analysis to determine that the formaldehyde conversion rate is 100%.

Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.