CN103991942B - The treatment process of chlorophenols Micropollutants in a kind of water body - Google Patents

Abstract

The invention provides a method for promoting Fe ³⁺ /H ₂ O ₂ system to degrade chlorophenol organic pollutants in waste water by using crustacean fluorescein. In order to solve the above-mentioned technical problems, the technical scheme of the present invention is as follows: control certain pH and temperature operating conditions, add crustacean fluorescein, Fe(III) salt and H ₂ O _2. Make them reach a certain multiple of the concentration of chlorophenols without special light conditions. After stirring for a certain period of time, the degradation percentage of chlorophenols pollutants in the water body can reach 93.5-98%. The present invention overcomes the problem that ultraviolet light radiation is required in the process of treating chlorophenol-contaminated wastewater by the traditional light-assisted advanced oxidation system. The method has the advantages of simple process, less equipment investment, low cost, and rapid and efficient treatment. It has broad application prospects in groundwater and chlorophenol-polluted water bodies with poor light transmission.

Description

A kind of treatment method of chlorophenols micro-pollutants in water body

technical field

_The invention relates to a method for using crustacean fluorescein to promote Fe3 ⁺ / _H2O2 system to degrade chlorophenol pollutants, which belongs to the improved advanced oxidation technology for removing chlorophenol pollutants in the environmental pollution control technology. The method can be used to treat chlorophenol pollutants in surface water with poor light transmission and groundwater.

Background technique

As important chemical, pharmaceutical and pesticide raw materials, intermediates or products, chlorophenols are widely used in the fields of disinfectants, fungicides, preservatives, pesticides, personal care products, etc. Chlorophenols will enter the environment through various channels, and are the most common One of the refractory organic pollutants. Due to its wide range of sources and its greater water solubility and "three-caused" toxic effects compared with general persistent organic pollutants, chlorophenols pose a general pollution threat to industrial wastewater, surface water, groundwater and soil, and pose a threat to human beings. serious harm to its ecological environment. For example, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol have become common refractory micro-pollutants with potential major health hazards in the advanced treatment of drinking water. Moreover, chlorophenols are the main precursor compounds of more toxic dioxin-like persistent pollutants. Therefore, five chlorophenols have been listed as priority pollutants by the US EPA. The removal of chlorophenol pollutants, especially the removal of low-concentration chlorophenol pollutants in water bodies, has always been a difficult problem in pollution control technology that human beings need to solve urgently.

For decades, people have been extensively carrying out scientific research and technology development on the degradation and removal of chlorophenol pollutants in water. Common treatment methods for chlorophenol pollutants include: chemical oxidation and chemical dechlorination and hydrogenation reduction, microbial transformation (biological reduction and oxidation), adsorption treatment, electrochemistry, photoelectric synergy, supercritical fluid, radiation degradation, incineration and other methods. For chlorophenol pollutants in water, the most widely studied treatment technology is Advanced Oxidation Processes (AOPs), especially photo-assisted advanced oxidation technology (Photo-AOPs) for the treatment of chlorophenol pollutants, such as O ₃ /UV, H ₂ O ₂ /UV, UV/O ₃ /H ₂ O ₂ , TiO ₂ /UV/H ₂ O ₂ , UV/Fenton, UV-vis/H ₂ O ₂ /iron oxalate, metal polyacid catalyst Environmentally friendly Photo-AOPs such as (POM) photocatalytic system have high processing efficiency and great development potential under certain operating conditions. The photo-assisted advanced oxidation process of degrading organic substrates is generally completed by the participation of H ₂ O ₂ . Except for the photoelectron transfer process, Photo-AOPs mainly generate HO through photochemical reactions. , organic substrates and HO. The reaction produces organic free radicals, and the dissolved oxygen in the water body in the photochemical reaction generates peroxy free radicals or peroxides to promote the entire oxidation process, and finally realize the mineralization of pollutants.

Existing photo-assisted AOPs generally have the problems of requiring ultraviolet radiation devices and energy consumption, especially when the treated wastewater is a turbid aqueous solution system, it is difficult for ultraviolet light to reach the vicinity of the pollutant molecules that need to be catalyzed to exert the photo-assisted effect. , which will lead to a large energy consumption and efficiency loss of the light-assisted advanced oxidation system. Therefore, by introducing substances with chemiluminescent properties into the solution system, the photogenerated electrons or holes that can be generated in the traditional photo-assisted advanced oxidation process are generated in the solution system, so as to achieve the transformation of light quantum from particles (molecules, atoms) in the solution system. or ions) to particles (molecules, atoms or ions) to achieve an advanced oxidation system that does not require light. In addition to being used for surface water containing chlorophenol pollutants, it can also be used for chlorophenol organic pollutants in groundwater. The treatment has great application prospects and economic value.

Contents of the invention

The present invention aims to overcome the high energy consumption of ultraviolet light radiation in the process of treating chlorophenol polluted wastewater by the traditional light-assisted advanced oxidation system, and the difficulty of ultraviolet light reaching the vicinity of pollutant molecules when treating chlorophenols in turbid aqueous solution, resulting in the loss of photocatalytic efficiency. Problem, provide a method for treating chlorophenol pollutants in wastewater.

For realizing above-mentioned purpose of the invention, the technical scheme that the present invention takes is as follows:

_A method for using crustacean fluorescein to promote the Fe3 ⁺ / _H2O2 system to degrade chlorophenol organic pollutants in wastewater, the steps are as follows: control certain pH and temperature operating conditions, when the chlorophenol concentration is 1-200mg/ Add crustacean fluorescein, Fe(III) salt and H ₂ O ₂ to the waste water of L to make them respectively reach a certain multiple of the chlorophenol concentration, without special light conditions, after stirring for a certain period of time, the chlorophenols in the water will be polluted The degradation percentage of the substance can reach 93.5-98%.

The crustacean fluorescein Chemiluminescent Cypridinaluciferinanalog (abbreviated as CLA) as mentioned above has a chemical name of 2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one.

Chlorophenol contaminants that can be treated as described above include 4-chlorophenol, 2-chlorophenol, 2,3-dichlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol.

Controlling the pH and temperature operating conditions as mentioned above refers to controlling the pH of the wastewater at 3-6 and controlling the temperature at 15-35°C during the treatment process.

As a preference, the added amount of the crustacean fluorescein CLA, Fe(III) salt and H ₂ O ₂ is m _(CLA) :m _{(chlorophenol)} =1:10～50, m _{(Fe(III) salt)} : m ( _{chlorophenol)} = 1: 5 to 20 and m _(H2O2) : m _{(chlorophenol)} = 2 to 20:1.

Fe(III) salts as used above refer to FeCl ₃ and Fe(NO ₃ ) ₃ .

Stirring treatment as mentioned above refers to stirring treatment for 0.5-2 hours under the condition of communicating with ambient air.

Compared with prior art, the beneficial effect of the present invention is:

① The present invention can overcome the high energy consumption of ultraviolet light radiation required by the traditional light-assisted advanced oxidation system to treat chlorophenol polluted wastewater, and when the treated wastewater is a turbid aqueous solution, it is difficult for ultraviolet light to reach the vicinity of pollutant molecules that need to be catalyzed and lose part The issue of photocatalytic efficiency.

② This method has the advantages of less investment in equipment, simple process, low cost, rapid and efficient treatment without secondary pollution, and has unique technical advantages in the treatment of groundwater containing chlorophenol pollutants and chlorophenol polluted water bodies with poor light transmission and broad application prospects.

Description of drawings

In order to further illustrate the process and effect of the crustacean fluorescein used in the crustacean fluorescein/Fe ³⁺ /H ₂ O ₂ advanced oxidation system and the removal of chlorophenols in water, the following figures are given.

1. Figure 1 is the molecular structural formula of crustacean fluorescein 2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one.

2. Fig. 2 is the HPLC (high performance liquid chromatography) spectrogram of this method before and after the degradation of 2,3-dichlorophenol. Wherein, (a) is the HPLC analysis spectrogram of 2,3-dichlorophenol wastewater parallel sample before treatment, and (b) is the HPLC analysis spectrogram after 20min of treatment. The HPLC testing conditions are: mobile phase (75% methanol: 23% water: 2% acetic acid, volume ratio), flow rate 1.0 mL/min. C18 reversed-phase column, column temperature 30°C, column front pressure 250×100kg/cm2. Ultraviolet light detector, the detection wavelength is 290nm. The injection volume is 8 μL. Figure 2 shows that the retention time of 2,3-dichlorophenol is t=8.3min. The degradation percentage of 2,3-dichlorophenol can be calculated as 82.98% by the reduction percentage of the peak area of 2,3-dichlorophenol before and after treatment for 20 minutes.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with specific embodiments. However, the invention is not limited to the listed examples.

Embodiment 1 measures 95mL self-preparation concentration as the 4-chlorophenol wastewater of 50mg/L, 1mL self-preparation concentration as the CLA aqueous solution of 100mg/L, 1mL self _- preparation concentration as the FeCl aqueous solution of 300mg/L and 3mL self-preparation concentration of Add 4000mg/L H ₂ O ₂ aqueous solution together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=5 and T=15°C, start stirring, and the degradation rate of 4-chlorophenol is 93.5% after 1 hour of treatment .

Embodiment 2 Measure 95mL self-preparation concentration as 2-chlorophenol waste water of 50mg/L, 1mL self-preparation concentration as the CLA aqueous solution of 200mg/L, 1mL self-preparation concentration as 500mg/ _L FeCl aqueous solution and 3mL self-preparation concentration of Add 6000mg/L H ₂ O ₂ aqueous solution together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=6 and T=25°C, start stirring, and after 0.5h of treatment, the degradation percentage of 2-chlorophenol is 94.3 %.

Example 3 Measure 95mL of 2,4-dichlorophenol wastewater with a self-made concentration of 50mg/L, 1mL of a self-made concentration of 400mg/L of CLA aqueous solution, 1mL of a self-made concentration of 500mg/ _L FeCl aqueous solution and 3mL of self-made Prepare H ₂ O ₂ aqueous solution with a concentration of 15000mg/L, add them together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=3 and T=35°C, start stirring, and after 2 hours of treatment, 2,4-dichloro The percentage of phenol degradation was 96.6%.

Example 4 Take 95mL of 2,4,6-trichlorophenol wastewater with a self-prepared concentration of 50mg/L, 1mL of a self-prepared concentration of 400mg/L CLA aqueous solution, and 1mL of a self-prepared concentration of 500mg/L Fe( _NO3 ) ₃ aqueous solution and 3mL self-prepared H ₂ O ₂ aqueous solution with a concentration of 5000mg/L were added together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjusted to pH=5 and T=15°C, started stirring, and treated for 1.5h The degradation percentage of 2,4,6-trichlorophenol was 95.7%.

Example 5 Measure 95mL of 2,3-dichlorophenol wastewater with a self-made concentration of 50mg/L, 1mL of a self-made concentration of 500mg/L of CLA aqueous solution, 1mL of a self-made concentration of 400mg/ _L FeCl aqueous solution and 3mL of self-made Prepare an aqueous solution of H ₂ O ₂ with a concentration of 8000mg/L, add them together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=3 and T=30°C, start stirring, and after 2 hours of treatment, 2,3 dichlorophenol The percent degradation was 96.3%.

Example 6 Measure 95mL of self-preparation concentration as 4-chlorophenol waste water of 50mg/L, 1mL of self-preparation concentration as the CLA aqueous solution of 200mg/L, 1mL of self _- preparation concentration as FeCl aqueous solution of 400mg/L and 3mL of self-preparation concentration of Add 10000mg/L H ₂ O ₂ aqueous solution together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=4 and T=25°C, start stirring, and after 1.5h of treatment, the degradation percentage of 4-chlorophenol is 95.8 %.

Example 7 Measure 95 mL of 2,3-dichlorophenol wastewater with a self-prepared concentration of 50 mg/L, 1 mL of a self-prepared CLA solution with a concentration of 400 mg/L, and 1 mL of a self-prepared concentration of 500 mg/L Fe(NO ₃ ) ₃ Add the aqueous solution and 3mL self-prepared H ₂ O ₂ aqueous solution with a concentration of 20000mg/L into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH = 4 and T = 30°C, start stirring, and after 2 hours of treatment, 2, The percentage of degradation of 3-dichlorophenol was 97.8%.

Example 8 Measure 85 mL of 4-chlorophenol waste water with a self-prepared concentration of 200 mg/L, 2 mL of a self-prepared concentration of 500 mg/L CLA aqueous solution, 3 mL of a self-prepared concentration of 500 mg/L Fe(NO ₃ ) ₃ aqueous solution and 10 mL Self-prepared H ₂ O ₂ aqueous solution with a concentration of 5000mg/L was added to a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjusted to pH = 3 and T = 25°C, started stirring, and treated for 1 hour to degrade 4-chlorophenol The percentage is 95.6%.

Example 9 Measure 85mL of 2,4-dichlorophenol wastewater with a self-prepared concentration of 100mg/L, 2mL of a self-prepared concentration of 300mg/L of CLA aqueous solution, 3mL of a self-prepared concentration of 200mg/ _L FeCl aqueous solution and 10mL of self-prepared Prepare H ₂ O ₂ aqueous solution with a concentration of 10000mg/L, add them together into a 250mL Erlenmeyer flask equipped with a magnetic stirrer, adjust pH=5 and T=30°C, start stirring, and after 2 hours of treatment, 2,4-dichloro The percentage of phenol degradation was 97.1%.

Claims (3)

1. one kind utilizes crustacean fluorescein to promote Fe ³⁺/ H ₂o ₂the method of chlorophenols organic pollutant in system degrading waste water, it is characterized in that: described crustacean fluorescein is the (ChemiluminescentCypridinaluciferinanalog (be abbreviated as CLA) of structure as shown in (I), 2-methyl-6-phenyl-3,7-dihydroimidazo [1,2-a] pyrazin-3-one; Control pH3 ~ 6 and temperature 15 ~ 35 DEG C are add CLA and Fe (III) salt and H in the waste water of 1 ~ 200mg/L in chlorophenol concentration ₂o ₂, make it reach the certain multiple of chlorophenol concentration respectively, add-on is m _(CLA): m _{(chlorophenol)}=1: 10 ~ 50, m _{(Fe (III) salt)}: m _{(chlorophenol)}=1: 5 ~ 20 and m _(H2O2): m _{(chlorophenol)}=2 ~ 20: 1, under connection ambient air and the condition without the need to special illumination, stir process, in water body, the degraded percentage of chlorophenol pollutant can reach 93.5 ~ 98%.

2. utilize crustacean fluorescein to promote Fe as claimed in claim 1 ³⁺/ H ₂o ₂the method of system degrading chlorophenol pollutant, is characterized in that: described chlorophenol pollutant is 4-chlorophenol, 2-chlorophenol, 2,3-Dichlorophenols, 2,4-Dichlorophenols or 2,4,6-trichlorophenol.

3. utilize crustacean fluorescein to promote Fe as claimed in claim 1 ³⁺/ H ₂o ₂the method of system degrading chlorophenol pollutant, is characterized in that: described Fe (III) salt is FeCl ₃or Fe (NO ₃) ₃.