阅读说明：本技术 一种采用气溶胶原位降解水中含硫嗅味物质的方法 (Method for in-situ degradation of sulfur-containing smelly substances in water by adopting aerosol ) 是由 周麒麟 何宇虹 吴述园 朱红生 于 2021-09-26 设计创作，主要内容包括：本发明公开了一种采用气溶胶原位降解水中含硫嗅味物质的方法,涉及水污染治理技术领域,为解决含硫嗅味物质去除方法或成本高,或难管理,或会造成二次污染的问题；本发明包括以下步骤：在水体表面布散气溶胶悬浮于水面上,加速含硫嗅味物质氧化降解,具体可以在含有含硫嗅味物质的水体表面附近安装有气溶胶发生装置,包括输送部分,其出液端安装有气溶胶喷头,气溶胶喷头固定安装于水体表面上方一定高度处,开启输送部分,气溶胶持续从气溶胶喷头喷出并在水面上布散,直到水体表面全部或部分被气溶胶覆盖,保持输送部分开启一段时间,加速含硫嗅味物质氧化降解；本发明使用简单、成本低廉,不会造成二次污染,能加速含硫嗅味物质氧化降解。(The invention discloses a method for degrading smelly substances containing sulfur in water in situ by using aerosol, which relates to the technical field of water pollution treatment and aims to solve the problems that the method for removing smelly substances containing sulfur is high in cost, difficult to manage or can cause secondary pollution; the invention comprises the following steps: the aerosol is dispersed on the surface of the water body and suspended on the water surface, so that the oxidative degradation of the odor-containing sulfur-containing substances is accelerated, and specifically, an aerosol generating device can be arranged near the surface of the water body containing the odor-containing sulfur-containing substances and comprises a conveying part, an aerosol spray head is arranged at the liquid outlet end of the conveying part, the aerosol spray head is fixedly arranged at a certain height above the surface of the water body, the conveying part is started, the aerosol is continuously sprayed out from the aerosol spray head and is dispersed on the water surface until the whole or part of the surface of the water body is covered by the aerosol, and the conveying part is kept started for a period of time, so that the oxidative degradation of the odor-containing sulfur-containing substances is accelerated; the method has the advantages of simple use, low cost, no secondary pollution and capability of accelerating the oxidative degradation of the sulfur-containing smelly substances.)

1. A method for in-situ degradation of sulfur-containing smelly substances in water by using aerosol is characterized by comprising the following steps: the aerosol is distributed on the surface of the water body and suspended on the water surface, so that the oxidative degradation of the sulfur-containing odor substances is accelerated.

2. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 1, comprising the steps of:

s1: the aerosol generating device is arranged near the surface of the water body containing the sulfur odor substances and comprises a conveying part, wherein an aerosol nozzle is arranged at the liquid outlet end of the conveying part, and the aerosol nozzle is fixedly arranged at a certain height above the surface of the water body;

s2: and (3) starting the conveying part, continuously spraying the aerosol from the aerosol spray head and spreading the aerosol on the water surface until the whole or part of the water surface is covered by the aerosol, and keeping the conveying part open for a period of time to accelerate the oxidative degradation of the sulfur-containing odor substances.

3. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 1, comprising: the sulfur-containing smelly substances comprise hydrogen sulfide, dimethyl disulfide, dimethyl trisulfide, diethyl disulfide, propyl sulfide and amyl sulfide.

4. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 1, comprising: the concentration of the smelly substances containing sulfur is 10-1000 ng/L, and the pH value of the water body is 5.4-9.4.

5. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 1, comprising: the aerosol is water aerosol, and the diameter of the aerosol is 0.01-1000 mu m.

6. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 2, comprising: the conveying part is an aerosol generator or liquid pumping equipment installed in fountain aeration engineering, water supplementing engineering, running water engineering, river channel ex-situ treatment technology and artificial wetland water treatment technology.

7. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 2, comprising: the liquid delivered by the delivery part includes but is not limited to in-situ extraction of a water body, an external water source or a solution with chemical agents added.

8. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 2, comprising: the distance between the aerosol spray head and the surface of the water body is 5-200 cm.

9. The method for in-situ degradation of sulfur-containing odorants in water by aerosol according to claim 2, comprising: the opening time of the conveying part is 0-24 h/day, and the aerosol covers 35-100% of the surface of the water body.

10. The method for in-situ degradation of sulfur-containing odorants in water according to any one of claims 1 to 9, comprising: respectively sampling before and after the aerosol is distributed in the water body for a period of time, analyzing by using a gas chromatography-mass spectrometer after sampling, adding sodium thiosulfate into the sample for quenching, and determining the concentration of sulfur-containing smelly substances.

Technical Field

The invention relates to the technical field of water pollution treatment, in particular to a method for degrading sulfur-containing smelly substances in water in situ by using aerosol.

Background

The sulfur-containing smelly substances refer to sulfur-containing substances released by growth, death and metabolism of algae, have high smelly activity intensity and concentration level in actual water body, and comprise hydrogen sulfide (H)₂S), Dimethyl disulfide (DMDS), Diethyl disulfide (DEDS), amyl sulfide (DAS), propyl sulfide (DPS), etc., which are two kinds of sulfur-containing compounds with strong volatility and special odor, and are often present in polluted water, and these compounds have low odor threshold and strong odor, and may cause damage to nerve endings of human body. Research shows that the traditional methods such as coagulation, precipitation and sand filtration have little effect on removing smelly substances, but sulfur-containing smelly substances are easily removed by oxidation, so that a plurality of scholars research on removing thioether substances by oxidation, such as:

a test research on the removal of methyl sulfide and dimethyl trisulfide from water by potassium permanganate (Chaocai, 2016.5.28, student's study of Hunan university) discloses that potassium permanganate has a removal effect on methyl sulfide and dimethyl trisulfide, the removal of dimethyl trisulfide requires 2 hours, and the reaction of potassium permanganate with methyl sulfide and dimethyl trisulfide conforms to a secondary kinetic reaction process;

research on the preoxidation removal of thioether odorants and the adsorption effect and mechanism of powdered activated carbon (Liao, 2021.6.14, the university of Beijing construction research thesis), KMnO was also studied₄、NaClO、ClO₂、H₂O₂、O₃The oxidation removal of DMDS, DEDS, DPS and DAS and the adsorption removal of 4 thioethers by activated carbon;

however, the above-mentioned oxidizing agents often cause various problems, such as that potassium permanganate easily causes heavy metal pollution, and may react with soluble organic substances to produce disinfection by-products and the like to cause secondary pollution; there are also other studies for the remediation of sulfur-containing odorants without using chemical oxidation, such as:

the research progress of the method for treating the volatile organic sulfide dimethyl disulfide gas (Yangyi bee, water purification technology 2021, 40(03)) introduces the adsorption, catalytic oxidation, biodegradation, low-temperature plasma purification, bioelectrochemical degradation and the like of DMDS, but the adsorption method is limited by adsorption capacity, and the adsorption material needs to be regenerated frequently, so that the management cost is high; the catalytic oxidation method, the low-temperature plasma purification method and the photocatalytic method have high treatment cost; the microbial inoculation and domestication of the biodegradation method requires long time, and the management is complex and tedious;

the existing methods are high in cost, difficult to manage or cause secondary pollution, so that a new method for treating the sulfur-containing smelly substances in the water is needed to solve the problems.

Disclosure of Invention

The invention aims to provide a method for degrading smelly substances containing sulfur in water in situ by using aerosol, so as to solve the problems that the removal method of smelly substances containing sulfur is high in cost, difficult to manage or causes secondary pollution.

In order to achieve the purpose, the invention provides the following technical scheme: a method for in-situ degradation of sulfur-containing smelly substances in water by using aerosol comprises the following steps: the aerosol is distributed on the surface of the water body and suspended on the water surface, so that the oxidative degradation of the sulfur-containing odor substances is accelerated.

In a preferred embodiment, the method specifically comprises the following steps:

s1: the aerosol generating device is arranged near the surface of the water body containing the sulfur odor substances and comprises a conveying part, wherein an aerosol nozzle is arranged at the liquid outlet end of the conveying part, and the aerosol nozzle is fixedly arranged at a certain height above the surface of the water body;

s2: and (3) starting the conveying part, continuously spraying the aerosol from the aerosol spray head and spreading the aerosol on the water surface until the whole or part of the water surface is covered by the aerosol, and keeping the conveying part open for a period of time to accelerate the oxidative degradation of the sulfur-containing odor substances.

Alternatively, the sulfur-containing odorants include hydrogen sulfide, dimethyl disulfide, dimethyl trisulfide, diethyl disulfide, propyl sulfide, pentyl sulfide, and the like.

Optionally, the concentration of the sulfur-containing smelly substances is 10-1000 ng/L.

Optionally, the pH value of the water body is 5.4-9.4.

Optionally, the aerosol is water aerosol, and the diameter of the aerosol is 0.01-1000 μm.

In the above scheme, optionally, the conveying part is an aerosol generator, or includes but is not limited to a liquid pumping device installed in a fountain aeration project, a water supplementing project, a running water project, a river channel ex-situ treatment technology and an artificial wetland water treatment technology.

Optionally, the liquid delivered by the delivery part includes, but is not limited to, in-situ extraction from a water body, an external water source, or a solution with chemical agents added.

In the scheme, the distance between the aerosol spray nozzle and the surface of the water body is 5-200 cm.

In the scheme, the opening time of the conveying part is 0-24 h/day.

In the scheme, the aerosol can cover 35-100% of the surface of the water body optionally.

Optionally, before the aerosol is distributed in the water body and after the aerosol is distributed in the water body for a period of time, sampling respectively, analyzing by using a gas chromatography-mass spectrometer after sampling, adding sodium thiosulfate into the sample for quenching, and determining the concentration of the sulfur-containing smelly substances.

Compared with the prior art, the invention has the beneficial effects that:

1. the method for degrading smelly substances containing sulfur in water in situ by using the aerosol can oxidize and degrade smelly substances containing sulfur in water in situ under the condition of basically not damaging natural environments such as water bodies, aquatic organisms and the like, and meanwhile, the aerosol distributed on the surface of the water body can inhibit the smelly substances containing sulfur in the water body from dissipating into the air.

2. According to the method for degrading the smelly sulfur-containing substances in the water in situ by using the aerosol, the oxidation of the smelly sulfur-containing substances can be accelerated only by introducing the aerosol on the surface of the water body, the degradation effect is good, the efficiency is high, no new pollutants are generated, and compared with a chemical oxidation method and the like, other agents are not required to be added, so that the occurrence of secondary pollution in the treatment process can be effectively avoided.

3. Compared with the conventional methods such as a Fenton oxidation method, an ozone oxidation method, a wet oxidation method and the like, the method for degrading the sulfur-containing smelly substances in water in situ by using the aerosol has the advantages of simple operation process, wider applicable pH range and the like, does not need special conditions such as temperature, illumination, pH and the like, can achieve better effect at normal temperature, and has good degradation effect under neutral and acidic conditions.

4. The method for degrading smelly substances containing sulfur in water in situ by using the aerosol has the advantages of low cost, simple use and operation, convenient modification and installation, capability of being combined with various existing devices, more convenience compared with a biodegradation method, and easier maintenance and management.

Detailed Description

A method for in-situ degradation of sulfur-containing smelly substances in water by using aerosol comprises the following steps:

s1: the aerosol generating device is arranged near the surface of a water body containing sulfur odor substances and comprises a conveying part, wherein the conveying part can be a common aerosol generator in the market or liquid pumping equipment arranged in the existing facilities such as a fountain aeration project, a water supplementing project, a running water project, a river channel ex-situ treatment technology, an artificial wetland water treatment technology and the like, liquid conveyed by the conveying part is preferably extracted in situ from the water body, and can also be an external water source or a solution added with a chemical agent and the like, wherein the in-situ extraction mode of the water body is optimal, an aerosol nozzle is arranged at the liquid outlet end of the conveying part, the aerosol nozzle is fixedly arranged at a certain height above the surface of the water body, and optionally, the aerosol nozzle is 5-200 cm away from the surface of the water body;

s2: and (3) starting the conveying part, continuously spraying the aerosol from the aerosol spray head and spreading the aerosol on the water surface until the whole or part of the water surface is covered by the aerosol, preferably, covering 35-100% of the water surface by the aerosol, keeping the conveying part open for a period of time, accelerating the oxidative degradation of sulfur-containing smelly substances, and optionally, starting the conveying part for 0-24 h/day.

The sulfur-containing smelling substances mainly include hydrogen sulfide, dimethyl disulfide, dimethyl trisulfide, diethyl disulfide, propyl sulfide, pentyl sulfide, etc.

The concentration of the sulfur-containing smelly substances in the water body to be treated can be 10-1000 ng/L.

The pH value of the water body can be 5.4-9.4.

Preferably, the aerosol is water aerosol, and the diameter of the aerosol can be 0.01-1000 μm.

In addition, sampling can be respectively carried out before aerosol is distributed in a water body and after the aerosol is distributed in the water body for a period of time, a gas chromatography-mass spectrometer is adopted for analysis after sampling, sodium thiosulfate is added into the sample for quenching, and the concentration of the sulfur-containing smelly substances is measured.

Example 1

This example was carried out in a laboratory, and the urban river water with black odor was taken and measured for hydrogen sulfide (H) as a sulfur-containing odorant₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 410, 220, 140, 120 and 47ng/L, respectively.

The black and odorous water is placed in three identical plastic containers (a container A, a container B and a container C) of 20x20x50cm, the liquid level is set to be 10cm, a pair of air vents is arranged at the position, 15cm higher than the container, air is pumped into one air vent through an air pump, air is exhausted from the other air vent, the air flow is controlled to be 0.03L/h, and the ventilation frequency of the upper space of the liquid level in the container is ensured to be 1 time/h. Taking one of the 3 containers set by the method as a container A; the other container B is provided with an external circulating water pump and a circulating water pipe (the water pipe takes water in situ, the water taking height is 5cm high in the container, and the water outlet pipe mouth is positioned at 12cm high in the container, namely 2cm above the liquid level); the other container C is provided with an external circulating water pump relative to the container A, and a circulating water pipe (the water pipe takes water in situ and takes water with the height of the container5cm high inside the container) and an aerosol spray head (the particle size of the water aerosol generated by the spray head is 6 +/-3 mu m) arranged at 12cm high inside the container. At the start of the experiment, both containers A, B, C were vented; the container B starts a circulating water pump (the circulating water flow is 20L/h); the container C was started with a circulating water pump for generating water aerosol (circulating water flow rate 20L/h) which spread over the entire liquid surface. And quickly obtaining black and odorous water samples in each container after 1500 seconds. Black odorous water in the container A contains sulfureted hydrogen (H) as odorous substance₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 398, 212, 136, 115 and 38ng/L, respectively; 377, 198, 121, 104 and 41ng/L in container B respectively; the contents of the containers C are respectively 308, 172, 101, 87 and 32ng/L, and the effect of accelerating the oxidative degradation of the sulfur-containing smelly substances is obvious.

Example 2

In the embodiment, the two polder with the interval of 10 meters and the area of 80 square meters are carried out in the concave bay of the north lake in Maanshan, and the water body is about 150 square. The experimental time is 6 in the middle of the month, the cyanobacteria pekoe erupts, the water body emits odor, the chlorophyll concentration reaches 2.167 mug/L, the total phosphorus is 0.40mg/L, the ammonia nitrogen concentration is 2.8mg/L, and the sulfur-containing odor substance hydrogen sulfide (H) is contained₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 212, 108, 76, 53 and 25ng/L, respectively.

An ordinary fountain aerator (circulation flux 14.5 m)³H, the spraying height is 0.8m, the dispersion diameter is 1.7m) is improved, so that 50 percent of the water sprayed by the fountain aerator is used for manually manufacturing hydrosol, the hydrosol is placed at the central water body of the polder for aeration and oxidation, and the water is set as a treatment group. And a fountain aerator of the same model without modification is arranged at the center of the other polder and is set as a comparison group, and a blank group is arranged at the other lake bay at the far end of the lake bay in which the experiment is carried out. Setting the aeration time of the experimental group to 8h every day, the duration time to 7 days, the weather during the experiment is clear, the average temperature is 28-31 ℃, and the aeration time is immediately obtained after the experiment is finishedThe water samples in each group, the treatment group and the comparison group are mixed with water samples (each zone is 500ml with the surface layer of 0-10cm, the middle layer of 90-100cm and the bottom layer of 190-200 cm) within the diameter range of 2.5-3m from the center of the aeration point, and the water samples are mixed in the blank group.

Water sample determination of hydrogen sulfide (H) in blank group₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 233, 123, 86, 52 and 38ng/L, respectively; the concentrations of the control groups were 156, 78, 36, 35 and 15ng/L, respectively; the concentrations of the treatment groups are respectively 102, 47, 23, 21 and 7ng/L, and the effect of accelerating the oxidative degradation of the sulfur-containing smelly substances is obvious; in addition, the odor around the upper part of the water surface is heavier in the whole aeration process of the contrast group and during sampling, a certain abnormal odor is also generated around the upper part of the water surface of the blank group, no obvious odor exists around the upper part of the water surface of the treatment group, and the sulfur-containing odor substances can be effectively prevented from dissipating.

Example 3

The embodiment is carried out in the water purification engineering of the side-road lake in Maanshan city, the lake has poor fluidity, a water replenishing source is a municipal rainwater pipe, and after rain, large smelly substances are scattered when the rainwater pipe enters the lake.

The water quality purification engineering of the south lake bypass is distributed in the west and east of the lake. The water body exchange time of the west concave bay and the south river channel is designed according to 2d, an ecological ditch 325m is newly built on the green land at the southeast side of the park footpath, and 1 submersible pump (Q is 180 m) is arranged at the position of the south lake and the south river channel near the flower rain road (Q is 180 m)³H, H is 5m, N is 5.5kW), the operation time is 24H, the river water body is lifted to the ecological channel, the water body is purified along the way through the ecological channel from south to north, and the purified water body returns to the south lake in the west bay, so that the bypass water quality purification of the south river channel and the west bay is formed. The water body exchange time of the east-side concave bay and the south river channel is designed according to 2d, an ecological ditch 400m is newly built in a green land at the southeast side of a park footpath, and 1 submersible pump (Q is 221 m) is arranged at a position of a flower-rain road of the south-lake-south river channel (Q is 221 m)³H, H is 5m, N is 5.5kW), the operation time is 24H, the river water body is lifted to the ecological channel, the river water body is purified along the ecological channel from south to north, and the purified water body returns to the south lake in the east concave bay, so that the river water body is purified, and the river water body is separated from the south to the north, and the river water body is separated from the south to the south lake in the east concave bay, so that the river water body is separated from the south to the southThe water quality purification of the south river and the east concave bay is formed.

In the east side bay bypass water quality purification project, 1 submersible pump (Q is 180 m) is arranged at the middle section of the ecological ditch³H5 m and N5.5 kW) and by setting a set of aerosol generating systems every 10m along the way for the manual generation of aqueous aerosol, the distribution system is located 35cm above the liquid level. After the experiment time is 6 in the middle of the month after rainfall once, the bypass purification systems on the east and west sides are started, and the aerosol generation system on the east side is started to form aerosol covering 80% of the liquid level above the liquid level. The experiment duration is 2 days, after the experiment, takes thing both sides bypass quality of water purification irrigation canals and ditches terminal water sample simultaneously for contain the analysis of sulphur smelly flavor substance. Measuring hydrogen sulfide (H) of west side (without artificial aerosol generator)₂The concentrations of S), Dimethyl disulfide (DMDS), Diethyl disulfide (DEDS), amyl sulfide (DAS) and propyl sulfide (DPS) are respectively 102, 58, 36, 22 and 18ng/L, and the east side is respectively 51, 28, 17, 10 and 8ng/L, so that the effect of accelerating the oxidative degradation of the sulfur-containing smelly substances is obvious.

Example 4

The embodiment is carried out in Ci lake and river wetland engineering in Maanshan city, the water replenishing source of the wetland is tail water of Wangshan sewage treatment plant, the tail water is lifted to a water storage tank through a lifting pump station to be subjected to chemical adding pretreatment and then is respectively conveyed to wetlands No. 1 and No. 2 through pipelines, the working process of the chemical adding pretreatment system is tap water → chemical adding (polyaluminium chloride) → submersible pump → pipelines are communicated to the water storage tank, and when tail water in the water storage tank has large odor substances, hydrogen sulfide (H) is measured₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 65, 27, 24, 18 and 15ng/L, respectively.

After a chemical adding system of the water storage tank is modified, the working flow of the chemical adding pretreatment system is tap water → chemical adding (polyaluminium chloride) → submersible pump → pipeline → aerosol generator communicated to the water storage tank (the total chemical adding solution amount is 85L/h and the chemical adding pretreatment system is placed 20cm above the liquid level and has 3 outlets in total).

Measurement of Hydrogen sulfide (H) after addition to the Aerosol Generator₂The concentrations of S), dimethyldisulfide (DMDS), diethyldisulfide (DEDS), amylsulfide (DAS) and propylsulfide (DPS) were 33, 14, 17, 7 and 4ng/L, respectively, and the odor was significantly reduced and weakened. The data are the average values of the time of one week immediately before and after the aerosol generator (water samples were collected at 13: 30-14: 30 per day), and the data collection time is 3 middle of 2021 years.

It is obvious from the four embodiments that the method for degrading the smelly sulfur-containing substances in the water in situ by using the aerosol realizes acceleration of oxidative degradation of the smelly sulfur-containing substances by dispersing the aerosol on the surface of the water body and suspending the aerosol on the surface of the water body, has obvious effect, can effectively control the smelly sulfur-containing substances to be dissipated into the air, and is low in cost, simple to modify and implement, environment-friendly, good in actual impression effect, free of influence on attractiveness and worthy of popularization.

The possible principle of the invention that the aerosol dispersed and suspended on the water surface accelerates the oxidative degradation of the sulfur-containing smelly substances is suspected as follows:

molecules are more accessible to the interface in an aerosol than in a solution. This is quantified by two characteristic lengths: the length of the compartment in which the molecule is confined and the average distance the molecule travels before the reaction. The water oxygen content in the aerosol is high, molecules existing in the aerosol contact a gas-liquid interface for many times before reaction, and the molecules do not exist in a solution stage. For such multiple contact gas-liquid interface reactions, surface entry may be achieved by increasing the ambient O to air/water interface₂The diffusion interaction accelerates the oxidation process and this process is enhanced because the reaction proceeds at different rates depending on the form of the sulfide.

In addition, the molecules may have different surface and volume pKa values (acidity coefficients), perhaps differing sulfur (lower valence) balances at the interface may be different. Under this possible hypothetical condition, the higher the degree of charge of the ion, the greater the energy cost of moving it to the air-water interface, for example: SO (SO)^3-Sulfuric acidThe salt is more likely to be present at the surface. Taking SO into account^3-Need to react with O₂The reaction proceeds and the sulfate is an inhibitor of the s (iv) oxidation, the relative surface propensity of the radical anion creating more favorable reaction conditions at the surface.

Another possible reason is the interaction with spontaneously generated hydrogen peroxide. Without the application of an external catalyst or voltage, pure water droplets on the micron scale can produce 30 μ M hydrogen peroxide due to the action of OH radicals at the interface. Since hydrogen peroxide is a strong oxidizing agent, even low concentrations contribute to the reaction acceleration, especially if hydrogen peroxide is continuously produced within a time scale of a few minutes. In addition, the hydrogen peroxide production interface may enhance the participation of free radical intermediates in sulfide oxidation.

There is also a guess that there may be a pH gradient inside the aerosol, but this is still one direction of investigation and there is controversy that the pH gradient produces droplets with a more basic core and a more acidic surface. The pH of the liquid drops is increased from the outside to the inside. The lower pH environment enhances the oxidation rate at the droplet surface. Thus, if a pH gradient does exist in the aerosol, which is an ideal reactor, the oxidation process will be fast at low interfacial pH, while a higher internal pH of the droplets will drive the complete reaction.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope defined by the claims.

The present invention is not described in detail, but is known to those skilled in the art.