CN114956299B - Method for Regulating Ferrous/polyphosphate System Oxidation/Reduction Degradation of Pollutants - Google Patents

Abstract

The application provides a method for regulating and controlling oxidation/reduction degradation pollutants of a ferrous/polyphosphate system, which relates to the field of environmental protection and comprises the following steps of ²⁺ /O ₂ TPP system degradation by controlling system pH and TPP/Fe ²⁺ Molar concentration ratio of (2) to regulate and control the molar concentration ratio of OH and O in the system ₂ ^·‑ Thereby achieving the purpose of controlling the oxidation/reduction degradation of pollutants in the system. The scheme regulates and controls the OH and O in the system by changing the reaction conditions ₂ ^·‑ The effect contribution of the system realizes the purpose of controlling the oxidation/reduction degradation of pollutants in the system, effectively solves the problem of poor effect of the system on removing the pollutants difficult to be oxidized and degraded, greatly widens the application range of the system, and has the advantages of simple process, low cost, environmental protection and the like compared with the traditional technology for regulating and controlling the oxidation/reduction degradation of the pollutants.

Description

Method for Regulating Oxidation/Reduction of Ferrous/polyphosphate System to Degrade Pollutants

technical field

The present application relates to the field of environmental protection, in particular to a method for regulating the oxidation/reduction degradation of pollutants in a ferrous/polyphosphate system.

Background technique

Oxygen is a green oxidant that exists naturally in the environment. It is difficult to directly oxidize and degrade organic pollutants under natural conditions. However, after oxygen is activated, it can form hydroxyl radicals (·OH), superoxide radicals (O ₂ ^·- ), etc. Active substance with strong reactivity.

Among the oxygen activation methods that have been reported so far, ferrous iron has become an ideal method for activating oxygen due to its low price, wide range of sources, and environmental friendliness. Studies have shown that Fe ²⁺ activates oxygen to produce active substances such as OH and O ₂ ^- , but its content in the system is extremely low and cannot effectively remove organic pollutants. Therefore, it is necessary to add appropriate oxygen-containing ligands to strengthen the active substances generation.

The reported oxygen-containing ligands include ethylenediaminetetraacetic acid, nitrilotriacetic acid, citric acid, oxalic acid, polyphosphate and disilicate, etc. Among them, polyphosphate (tetrapolyphosphoricacid, TPP) is widely used because it can effectively promote the production of active substances in the system, does not compete with organic pollutants for active species, and is green and non-toxic as a food additive. However, the current Fe ²⁺ /O ₂ /TPP system mainly emphasizes the oxidation of OH, while ignoring the reduction of O ₂ ^·- in the system, which makes the system poor in removing refractory pollutants and has a limited application range. narrow.

Contents of the invention

The purpose of this application is to provide a method for regulating the oxidation/reduction degradation of pollutants in the ferrous/polyphosphate system, which aims to solve the problem of poor removal effect of the system on refractory pollutants and greatly broaden the scope of application of the system .

In order to achieve the above object, the application provides a method for regulating and controlling the oxidation/reduction of ferrous/polyphosphate system to degrade pollutants, including:

Add ferrous ions and polyphosphates to the pollutants to be treated to form a reaction system, and continuously feed _O2 into the system to control the molar ratio of polyphosphates and ferrous ions between 0.5 and 3 The pH of the control system is changed between 2 and 8 to carry out oxidative degradation and reductive degradation of the pollutants to be treated.

Preferably, the molar ratio between the polyphosphate and the ferrous ion is controlled to be 1.5 to 2.5, and the pH of the system is controlled to vary between 2 and 8, so as to oxidatively degrade and degrade the pollutants to be treated. Reductive degradation;

Wherein, when the pH of the system is controlled to be 2 to 4, the pollutants to be treated are mainly oxidatively degraded;

When the pH of the system is controlled to be 4-8, the pollutants to be treated are mainly reduced and degraded.

Preferably, the molar ratio of the polyphosphate to the ferrous ion is controlled to be 2, and the pH of the system is controlled to vary between 3 and 7, so as to carry out oxidative degradation and reductive degradation of the pollutants to be treated ;

Wherein, when the pH of the system is controlled to be 3-4, the pollutants to be treated are mainly oxidatively degraded;

When the pH of the system is controlled to be 5-7, the pollutants to be treated are mainly reduced and degraded.

Preferably, the pH of the system is controlled to be 6 to 8, and the molar ratio of the polyphosphate to the ferrous ion is controlled to vary between 0.5 and 3, so as to oxidize and degrade the pollutants to be treated and Reductive degradation;

Wherein, when the molar ratio of the polyphosphate and the ferrous ion is controlled to be 0.5-1, the pollutants to be treated are mainly oxidatively degraded;

When the molar ratio between the polyphosphate and the ferrous ion is controlled to be greater than 1 and less than or equal to 3, the pollutants to be treated are mainly reduced and degraded.

Preferably, the pH of the system is controlled to be 7, and the molar ratio of the polyphosphate to the ferrous ion is controlled to vary between 0.5 and 3, so as to perform oxidative degradation and reductive degradation of the pollutants to be treated ;

Wherein, when the molar ratio of the polyphosphate and the ferrous ion is controlled to be 0.5-1, the pollutants to be treated are mainly oxidatively degraded;

When the molar ratio of the polyphosphate to the ferrous ion is controlled to be 2-3, the pollutants to be treated are mainly reduced and degraded.

Preferably, the ferrous ion is selected from any one or more of ferrous sulfate, ferrous chloride, and ferrous hydroxide.

Preferably, the polyphosphate ions include tetrapolyphosphate ions and/or tripolyphosphate ions.

Preferably, the tetrapolyphosphate ion comprises any one or more of tetrapolyphosphoric acid, sodium tetrapolyphosphate, potassium tetrapolyphosphate and ammonium tetrapolyphosphate; the tripolyphosphate ion comprises tripolyphosphoric acid, Any one or more of sodium tripolyphosphate, potassium tripolyphosphate and ammonium tripolyphosphate.

Preferably, the O ₂ flow rate is 100-200 mL/min.

Compared with the prior art, the beneficial effects of the present application include:

The method for degrading pollutants provided by this application is the degradation method of Fe ²⁺ /O ₂ /TPP system, by controlling the pH of the system and the molar concentration ratio of TPP/Fe ²⁺ to regulate the production of OH and O ₂ ^- in the system, Then achieve the purpose of controlling the oxidation/reduction degradation of pollutants in the system. By changing the reaction conditions and adjusting the contribution of OH and O ₂ ^- in the system, this scheme achieves the purpose of controlling the oxidation/reduction degradation of pollutants in the system, and effectively solves the problem of poor removal effect of the system on refractory pollutants. , which greatly broadens the application range of the system. Compared with the traditional technology of regulating the oxidation/reduction degradation of pollutants, the system has the advantages of simple process, low cost, and environmental friendliness.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings that are required in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus should be considered as limiting the scope of the application.

Figure 1 is the results of pollutant degradation by Fe ²⁺ /O ₂ /TPP system under different pH conditions;

Fig. 2 is a diagram showing the results of pollutant degradation by the Fe ²⁺ /O _{2 /} TPP system under different TPP/Fe ²⁺ molar ratios.

Detailed ways

As used herein:

"Prepared from" is synonymous with "comprising". As used herein, the terms "comprises," "including," "has," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, step, method, article, or device comprising listed elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to such composition, step, method, article, or device. elements.

The conjunction "consisting of" excludes any unspecified elements, steps or components. If used in a claim, this phrase will make the claim closed so that it does not contain material other than those described except for the customary impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately after the subject matter, it only defines the elements described in that clause; other elements are not excluded from the claims as a whole. beyond the claims.

When amounts, concentrations, or other values or parameters are expressed in terms of ranges, preferred ranges, or ranges bounded by a series of upper preferred values and lower preferred values, it is to be understood that any range upper or preferred value combined with any lower range limit is specifically disclosed. All ranges formed by any pairing of values or preferred values, whether or not such ranges are individually disclosed. For example, when the range "1-5" is disclosed, the described range should be construed to include the ranges "1-4", "1-3", "1-2", "1-2 and 4-5" , "1 ~ 3 and 5" and so on. When a numerical range is described herein, unless otherwise stated, that range is intended to include its endpoints and all integers and fractions within the range.

In these examples, unless otherwise specified, the stated parts and percentages are by mass.

"Parts by mass" refers to the basic measurement unit that expresses the mass ratio relationship of multiple components, and 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass part of A component is a part, and the mass part of B component is b part, it means that the mass ratio of A component to B component is a:b. Alternatively, it means that the mass of component A is aK, and the mass of component B is bK (K is an arbitrary number, representing a multiple factor). It should not be misunderstood that, unlike the parts by mass, the sum of parts by mass of all components is not limited to 100 parts.

"And/or" is used to indicate that one or both of the stated situations may occur, for example, A and/or B includes (A and B) and (A or B).

The application provides a method for regulating and controlling the oxidation/reduction of pollutants in the ferrous/polyphosphate system, for example, it can be used to treat waste liquid, or the solution state of solid pollutants. The method includes: adding Ferrous ions and polyphosphate form a reaction system, and O ₂ is continuously introduced into the system to control the molar ratio between polyphosphate and ferrous ions to vary between 0.5 and 3, and to control the pH of the system Change between 2 and 8 to perform oxidative degradation and reductive degradation on the pollutants to be treated.

The method for degrading pollutants provided by this application is the degradation method of Fe ²⁺ /O ₂ /TPP system, by controlling the pH of the system and the molar concentration ratio of TPP/Fe ²⁺ to regulate the production of OH and O ₂ ^- in the system, Then achieve the purpose of controlling the oxidation/reduction degradation of pollutants in the system. By changing the reaction conditions and adjusting the contribution of OH and O ₂ ^- in the system, this scheme achieves the purpose of controlling the oxidation/reduction degradation of pollutants in the system, and effectively solves the problem of poor removal effect of the system on refractory pollutants. , which greatly broadens the application range of the system. Compared with the traditional technology of regulating the oxidation/reduction degradation of pollutants, the system has the advantages of simple process, low cost, and environmental friendliness.

Wherein, ferrous ions are ferrous ions in dissolved state, and this scheme is not applicable to solid minerals containing Fe(II). The ferrous ion may be selected from any one or more of ferrous sulfate, ferrous chloride, and ferrous hydroxide, for example.

Wherein, the polyphosphate ion includes tetrapolyphosphate ion and/or tripolyphosphate ion. Described tetrapolyphosphate ion comprises any one or more in tetrapolyphosphoric acid, sodium tetrapolyphosphate, potassium tetrapolyphosphate and ammonium tetrapolyphosphate; Described tripolyphosphate ion comprises tripolyphosphoric acid, tripolyphosphoric acid Any one or more of sodium, potassium tripolyphosphate and ammonium tripolyphosphate.

Wherein, O ₂ may be introduced into the system in the form of air or in the form of pure oxygen, which is not specifically limited here. The O ₂ flow rate may be, for example, 100-200 mL/min, for example, 100 mL/min, 120 mL/min, 150 mL/min, 160 mL/min, 180 mL/min or 200 mL/min.

The reaction mechanism of the system includes the following processes:

O ₂ +Fe(TPP) ²⁺ →O ₂ ^·- +Fe(TPP) ³⁺

O ₂ ^·- +Fe(TPP) ²⁺ +2H ⁺ →H ₂ O ₂ +Fe(TPP) ³⁺

Fe(TPP) ²⁺ +H ₂ O ₂ →Fe(TPP) ³⁺ +2·OH

On the one hand, the generation process of the above reaction mechanism is strongly affected by the pH of the solution. When the pH is low, such as 2 to 4, the O ₂ ^·- generated by the activation of O ₂ in the system is rapidly converted into ·OH, and the system has a strong oxidation pollutants are oxidized and degraded; when the pH is high, such as 4-8, the conversion rate of O ₂ ^·- to H ₂ O ₂ in the system is significantly inhibited, resulting in the accumulation of O ₂ ^·- in the solution, and the system has a strong Reducibility, making pollutants degraded by reduction. Therefore, adjusting the pH can be used to adjust whether the system is suitable for oxidative degradation or reductive degradation. In a pollutant to be treated, there are usually substances that need to be oxidatively degraded and reductively degraded. By adjusting the pH in a reaction system to change within the range of 2 to 8, different substances can be degraded.

On the other hand, the molar ratio of TPP/Fe ²⁺ in the solution will change the composition of Fe ²⁺ -TPP complex in the system. Under neutral conditions, Fe ²⁺ -TPP complexes mainly form [Fe(H ₂ O) ₆ ] ²⁺ , [Fe(TPP)(H ₂ O) ₃ ] ^- and [Fe(TPP) ₂ ] ^4- , in which [Fe(TPP)(H ₂ O) ₃ ] ^- and [Fe(TPP) ₂ ] ^4- have obvious activity for the generation of O ₂ ^·- in the system, while the generation of ·OH is mainly based on [Fe(TPP)(H ₂ O) ₃ ^] -mainly.

When the concentration of Fe ²⁺ in the system is greater than the concentration of TPP, the complexes in the system are mainly [Fe(TPP)(H ₂ O) ₃ ] ^- , and O ₂ ^·- is rapidly activated to produce ·OH, and the system has strong oxidizing properties , the pollutants are oxidized and degraded; when the Fe ²⁺ concentration in the system is lower than the TPP concentration, [Fe(TPP) ₂ ] ^4- is the main content in the system, and O ₂ is activated to produce a large amount of O ₂ ^·- , The system has strong reducibility, and the pollutants are reduced and degraded. Therefore, this scheme can also realize the oxidation/reduction degradation of pollutants by adjusting the TPP/Fe ²⁺ molar ratio change in the system.

It can be understood that the system can have good reductive degradation for organic pollutants containing electron-withdrawing groups such as halogen or nitro; for pollutants containing electron-donating groups such as hydroxyl or methyl, the system can have good oxidative degradation.

In one embodiment, the molar ratio between the polyphosphate ion and the ferrous ion is controlled to be 1.5-2.5, for example, it can be 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 or 2.5; controlling the pH of the system to vary between 2 and 8, so as to oxidatively degrade and reductively degrade the pollutants to be treated.

Wherein, when the pH of the system is controlled to be 2-4, the O ₂ ^·- generated by the activation of O ₂ in the system is rapidly converted into ·OH, the system has strong oxidative properties, and the pollutants to be treated are mainly oxidatively degraded.

Wherein, when the pH of the system is controlled to be 4-8, the conversion rate of O ₂ ^·- to H ₂ O ₂ in the system is significantly inhibited, resulting in the accumulation of O ₂ ^·- in the solution, and the system has strong reducibility, which is harmful to the The pollutants to be treated are mainly reduced and degraded.

In a preferred embodiment, the pH of the system is controlled to be 3-4, so as to oxidatively degrade the pollutants to be treated.

In a preferred embodiment, the molar ratio of the polyphosphate ions to the ferrous ions is controlled to be 2, and the pH of the system is controlled to vary between 3 and 7, so as to oxidatively degrade the pollutants to be treated and reductive degradation.

Wherein, when the pH of the system is controlled to be 3-4, the pollutants to be treated are mainly oxidatively degraded. The pH of the system is controlled to be 5-7, and the pollutants to be treated are mainly reduced and degraded.

In another embodiment, the pH of the system is controlled to be 6-8, for example, the pH can be 6, 7 or 8, and the molar ratio of the polyphosphate ion to the ferrous ion is controlled between 0.5-3 to perform oxidative degradation and reductive degradation on the pollutants to be treated.

Wherein, when the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be 0.5-1, the complex in the system is mainly [Fe(TPP)(H ₂ O) ₃ ] ^- , and the O ₂ ^{· -It} is rapidly activated to produce OH, the system has strong oxidative properties, and mainly oxidizes and degrades the pollutants to be treated.

Wherein, when the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be greater than 1 and less than or equal to 3, [Fe(TPP) ₂ ] ^4- is mainly used in the system, and O ₂ is activated to produce With a large amount of O ₂ ^·- , the system has strong reducibility, and the pollutants to be treated are mainly reduced and degraded.

Preferably, the pH of the system is controlled to be 7, and the molar ratio between the polyphosphate ion and the ferrous ion is controlled to vary between 0.5 and 3, so as to oxidatively degrade and reduce the pollutants to be treated degradation;

Wherein, when the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be 0.5-1, the pollutants to be treated are mainly oxidatively degraded;

Wherein, when the molar ratio of the polyphosphate ions and the ferrous ions is controlled to be 2-3, the pollutants to be treated are mainly reduced and degraded.

The implementation of the present application will be described in detail below in conjunction with specific examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application, and should not be considered as limiting the scope of the present application. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all conventional products that could be purchased from the market. Unless otherwise specified, the volume of the system solution in the examples is 100ml.

Example 1

Add 20mM TPP (sodium tripolyphosphate) and 10mM Fe ²⁺ (FeSO ₄ 7H ₂ O) to the 10mg/L p-nitrophenol solution to be treated, and dissolve TPP and Fe ²⁺ by stirring or shaking , then continuously supply air to the system, the air flow rate is 150ml/min, the pH of the system is adjusted to be 3, and the degradation of p-nitrophenol is detected.

Add 20mM TPP and 10mM Fe ²⁺ into the 10mg/L benzoic acid solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, Adjust the pH of the system to 3, and detect the degradation of benzoic acid.

Example 2

Add 20mM TPP and 10mM Fe ²⁺ to the 10mg/L p-nitrophenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system, the air flow rate is 150ml/ min, adjust the pH of the system to 5, and detect the degradation of p-nitrophenol.

Add 20mM TPP and 10mM Fe ²⁺ into the 10mg/L benzoic acid solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, Adjust the pH of the system to 5, and detect the degradation of benzoic acid.

Example 3

Add 20mM TPP and 10mM Fe ²⁺ to the 10mg/L p-nitrophenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system, the air flow rate is 150ml/ min, adjust the pH of the system to 7, and detect the degradation of p-nitrophenol.

Add 20mM TPP and 10mM Fe ²⁺ into the 10mg/L benzoic acid solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, Adjust the pH of the system to 7, and detect the degradation of benzoic acid.

The results of pollutant degradation by the Fe ²⁺ /O ₂ /TPP system under different pH conditions from Examples 1 to 3 are shown in FIG. 1 . When the solution pH ₌ 3, OH in ^the system plays a major role, and the pollutants are mainly oxidized and degraded; Phenols are mainly degraded by reduction.

Figure 1 shows the removal effect of the system on p-nitrophenol (difficult to oxidize and easily reduce) and benzoic acid (easily oxidize and hardly reduce) under different pH conditions. It can be seen that the degradation effect of the system on p-nitrophenol, which is difficult to oxidize and easily reduce, is the best at pH=5, and under the conditions of pH=5 and 7, the reductive degradation of p-nitrophenol is obviously stronger than that of pH=3; Benzoic acid, which is easy to oxidize and hard to reduce, has the best degradation effect under the condition of pH=3, and the oxidation degradation of benzoic acid is obviously stronger than the reduction degradation.

Example 4

Add 5mM TPP and 10mM Fe ²⁺ into the 5mg/L tetrabromobisphenol A solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system with an air flow rate of 150ml /min, adjust the pH of the system to be stable at 7, and detect the degradation of tetrabromobisphenol A.

Add 5mM TPP and 10mM Fe ²⁺ into the 10mg/L phenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, adjust The pH of the system was stable at 7, and the degradation of phenol was detected.

Example 5

Add 10mM TPP and 10mM Fe ²⁺ to the 5mg/L tetrabromobisphenol A solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system with an air flow rate of 150ml /min, adjust the pH of the system to be stable at 7, and detect the degradation of tetrabromobisphenol A.

Add 10mM TPP and 10mM Fe ²⁺ to the 10mg/L phenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, adjust The pH of the system was stable at 7, and the degradation of phenol was detected.

Example 6

Add 20mM TPP and 10mM Fe ²⁺ to the 5mg/L tetrabromobisphenol A solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system with an air flow rate of 150ml /min, adjust the pH of the system to be stable at 7, and detect the degradation of tetrabromobisphenol A.

Add 20mM TPP and 10mM Fe ²⁺ into the 10mg/L phenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, adjust The pH of the system was stable at 7, and the degradation of phenol was detected.

Example 7

Add 30mM TPP and 10mM Fe ²⁺ to the 5mg/L tetrabromobisphenol A solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, and then continuously supply air to the system with an air flow rate of 150ml /min, adjust the pH of the system to be stable at 7, and detect the degradation of tetrabromobisphenol A.

Add 30mM TPP and 10mM Fe ²⁺ into the 10mg/L phenol solution to be treated, dissolve TPP and Fe ²⁺ by stirring or shaking, then continuously supply air to the system, the air flow rate is 150ml/min, adjust The pH of the system was stable at 7, and the degradation of phenol was detected.

The results of pollutant degradation by the Fe ²⁺ /O ₂ /TPP system under different TPP/Fe ²⁺ molar ratios from Examples 4 to 7 are shown in FIG. 2 . Figure 2 shows the removal effect of tetrabromobisphenol A (difficult to oxidize and easily reduce) and phenol (easily oxidize and hardly reduce) under different TPP/Fe ²⁺ molar ratios. It can be seen that the degradation effect of the system on tetrabromobisphenol A when the molar ratio of TPP/Fe ²⁺ > 1 is significantly better than that of the TPP/Fe ²⁺ molar ratio ≤ 1, and the molar ratio of TPP/Fe ²⁺ > 1 Tetrabromobisphenol A had the best reductive degradation effect; for phenol, the system had the best degradation effect under the condition of TPP/Fe ²⁺ molar ratio≤1, and the oxidative degradation of phenol was obviously stronger than the reductive degradation.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; although the application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present application. scope.

In addition, those skilled in the art will appreciate that although some embodiments herein include some features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the present application. And form different embodiments. For example, in the following claims, any one of the claimed embodiments may be used in any combination. The information disclosed in the background technology section is only intended to deepen the understanding of the general background technology of the application, and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art known to those skilled in the art.

Claims (7)

1. a method for regulating and controlling ferrous iron/polyphosphate system oxidation/reduction degradation pollutant, is characterized in that, comprises: Add ferrous ions and polyphosphate ions to the pollutants to be treated to form a reaction system, and continuously feed _O2 into the system; controlling the molar ratio of the polyphosphate ion to the ferrous ion to be 1.5 to 2.5, and controlling the pH of the system to vary between 2 and 8, so as to carry out oxidative degradation and reductive degradation of the pollutants to be treated ; Wherein, when the pH of the system is controlled to be 2 to 4, the pollutants to be treated are mainly oxidatively degraded; When the pH of the system is controlled to be 4-8, the pollutants to be treated are mainly reduced and degraded; Or, control the pH of the system to be 6-8, control the molar ratio of the polyphosphate ion and the ferrous ion to vary between 0.5-3, so as to oxidize and degrade the pollutants to be treated and Reductive degradation; Wherein, when the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be 0.5-1, the pollutants to be treated are mainly oxidatively degraded; When the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be greater than 1 and less than or equal to 3, the pollutants to be treated are mainly reduced and degraded. 2. method according to claim 1, is characterized in that, the mol ratio of controlling described polyphosphate ion and described ferrous ion is 2, controls the pH of described system to change between 3～7, with performing oxidative degradation and reductive degradation on the pollutants to be treated; Wherein, when the pH of the system is controlled to be 3-4, the pollutants to be treated are mainly oxidatively degraded; When the pH of the system is controlled to be 5-7, the pollutants to be treated are mainly reduced and degraded. 3. method according to claim 1, is characterized in that, the pH of controlling described system is 7, controls the mol ratio of described polyphosphate ion and described ferrous ion to change between 0.5～3, with performing oxidative degradation and reductive degradation on the pollutants to be treated; Wherein, when the molar ratio of the polyphosphate ion and the ferrous ion is controlled to be 0.5-1, the pollutants to be treated are mainly oxidatively degraded; When the molar ratio of the polyphosphate ions and the ferrous ions is controlled to be 2-3, the pollutants to be treated are mainly reduced and degraded. 4. The method according to any one of claims 1 to 3, wherein the ferrous ion is selected from any one or more of ferrous sulfate, ferrous chloride, and ferrous hydroxide. 5. The method according to any one of claims 1 to 3, wherein the polyphosphate ion comprises tetrapolyphosphate ion and/or tripolyphosphate ion. 6. The method according to claim 5, wherein the tetrapolyphosphate ion comprises any one or more of tetrapolyphosphoric acid, sodium tetrapolyphosphate, potassium tetrapolyphosphate and ammonium tetrapolyphosphate; The tripolyphosphate ion includes any one or more of tripolyphosphoric acid, sodium tripolyphosphate, potassium tripolyphosphate and ammonium tripolyphosphate. 7. The method according to claim 1, characterized in that the _O2 flow rate is 100-200 mL/min.

Images