CN113880187A

CN113880187A - Treatment process for treating organic sewage by using electron beam irradiation and catalyst

Info

Publication number: CN113880187A
Application number: CN202111033258.8A
Authority: CN
Inventors: 曹留烜
Original assignee: Xiamen University
Current assignee: Xiamen University
Priority date: 2021-09-03
Filing date: 2021-09-03
Publication date: 2022-01-04

Abstract

A treatment process for treating organic sewage by electron beam irradiation and a catalyst relates to the field of water treatment. The method comprises an electron beam catalysis unit, and the method for degrading organic matters in the electron beam catalysis unit comprises the following steps: (1) carrying out electron beam irradiation on the organic sewage; (2) contacting the organic wastewater with a catalyst; wherein, the step (1) and the step (2) are carried out simultaneously or successively after an interval time which is less than or equal to 1 min; the catalyst comprises an active metal element selected from at least one of magnesium, aluminium and transition metals, the active metal element being present in an insoluble solid form, and optionally a support. The method has the advantages of capability of degrading organic pollutants to the first-class A standard environment-friendly discharge standard with low cost, high speed and high efficiency, good economy, no risk of newly-increased hazardous waste and salinity and the like.

Description

Treatment process for treating organic sewage by using electron beam irradiation and catalyst

Technical Field

The invention relates to the field of water treatment, in particular to a treatment process for treating organic sewage by using electron beam irradiation and a catalyst.

Background

At present, a membrane filtration method is adopted, pollutants in sewage are mainly subjected to membrane separation, 40% -60% of clear water is discharged after membrane separation, and concentrated water formed by enrichment of residual pollutants is difficult to obtain effective treatment and discharge.

The garbage leachate membrane treatment process adopts the treatment process flows of biochemistry, ultrafiltration, nanofiltration and Reverse Osmosis (RO), and has the advantages of large investment, small treatment capacity and low treatment efficiency. Particularly, concentrated water generated in the sewage membrane treatment process is usually used as landfill leachate after being recharged to a landfill for secondary adsorption, and the process flow is repeated; after the operation for a period of time, part of the concentrated water in the recharge landfill site loses the secondary adsorption capacity, so that the concentration of the landfill leachate is higher and higher, and the treatment difficulty is higher and higher. And the ultra-high water inlet concentration causes the membrane system to carry out back washing operation frequently, reduces the service life of the membrane treatment system, gradually reduces the yield of clear water, and continuously improves the operation and maintenance cost.

There is a significant technical bottleneck in the conventional processes represented by fenton, catalytic ozonation and biochemical treatment: 1. most of the long-chain polluted organic matters are difficult to achieve the degradation target through a sewage biochemical process; 2. long-chain organic pollutants can not be used as nutrient substances of microorganisms in the sewage biochemical process, and a large amount of carbon sources are added to maintain the operation of a biochemical system; 3. the single-stage Fenton and ozone catalytic oxidation have low treatment efficiency on most of long-chain polluted organic matters, and a multi-stage treatment unit needs to be built for achieving the treatment target, so that the sewage treatment process has the problems of long flow, high treatment cost, complex operation, poor stability and the like; 4. in the single-stage Fenton and ozone catalytic oxidation process, a large amount of chemical agents are required to be added, a large amount of hazardous waste sludge is generated in the treatment process, the hazardous waste treatment cost is increased, and meanwhile, the risk of environmental hidden danger is increased; 5. dissolved oxidants and the like are used in a large amount in the Fenton and ozone catalytic oxidation process, so that the salinity and other toxic and harmful components in the sewage are increased, the process unit can only be used as a tail end treatment unit, the ecological damage of tail water discharge to a receiving water body is obvious, and the discharge standard is difficult to reach in the environment with salinity requirement on discharge.

At present, one of the main problems faced in the field of sewage treatment is: when processing high molecular compounds, the method has the difficulties of difficult degradation, high cost, complex process, secondary pollution brought by the processing process and the like. Therefore, it is important to develop a method capable of simply and efficiently treating high molecular weight compounds.

Electron beam irradiation catalysis is a potential, rapid and efficient method, but at present, the research on electron beam irradiation catalysis is not much, and a method of matching electron beam irradiation with a catalyst for degrading high-molecular organic pollutants is not seen.

Disclosure of Invention

The invention aims to overcome the problems of the existing sewage treatment process and provide a treatment process for treating organic sewage by combining electron beam irradiation with a catalyst. The catalyst and electron beam irradiation are mutually matched, so that high-molecular organic compounds can be effectively degraded, and the catalyst has a good degradation effect especially on high-concentration organic compounds and high-molecular organic matters which are difficult to degrade and have long chains, and is low in cost, quick and efficient; can thoroughly degrade organic pollutants to the emission standard, has good economical efficiency and has no risk of newly increasing hazardous waste and salinity.

The invention provides an organic sewage treatment process, which comprises an electron beam catalysis unit, and a method for degrading organic matters in the electron beam catalysis unit, specifically, the invention comprises the following steps:

1) carrying out electron beam irradiation on the organic sewage;

2) contacting the organic wastewater with a catalyst;

wherein, the step 1) and the step 2) are carried out simultaneously, or are carried out successively after an interval time, and the interval time is less than or equal to 1 min;

the catalyst comprises an active metal element selected from at least one of alkaline earth metals, transition metals and the like, and an optional carrier, wherein the active metal element exists in an insoluble solid form.

In step 1), the conditions for the electron beam irradiation may use conditions conventional in the art. According to the preferred specific implementation mode, the energy of electron beam irradiation is 1.0-3.0 MeV, and the beam intensity is 80-200 mA.

More preferably, the energy of the electron beam irradiation is 1.2-2.8 MeV, and the beam intensity is 100-140 mA.

In the current technique, the time of electron beam irradiation is instantaneous, and therefore the time of single irradiation is not particularly limited, for example, the time of single irradiation is < 1 s.

The step 1) and the step 2) can be carried out simultaneously. In this case, an exemplary embodiment is: the catalyst is already present in the organic sewage, and then the mixture of the catalyst and the organic sewage is subjected to electron beam irradiation. The term "simultaneously performed" in the present invention does not mean that step 1) and step 2) need to be continued for the same time, since electron beam irradiation usually occurs instantaneously; the term in the present invention means that the catalyst is present in the organic wastewater when electron beam irradiation is performed.

The step 1) and the step 2) can also be carried out successively and separated by one interval time. In this case, an exemplary embodiment is: the flowing organic sewage is irradiated by electron beams through an electron beam irradiation device and then flows through a section of flow path with a catalyst.

Under the environment that electron beams generate free radicals, organic sewage is contacted with a catalyst, so that a good catalytic effect can be generated, and molecular chains of high-molecular organic matters are broken. In order to ensure sufficient free radical environment, when the processes are carried out successively, the interval time is less than or equal to 1 min; preferably ≦ 30s, more preferably ≦ 10 s.

In step 2), the contact time with the catalyst may be long, but for the purpose of shortening the time as much as possible and ensuring a good effect, the contact time with the catalyst is preferably 1s to 10min, more preferably 5s to 5 min. The contact time refers to the contact time of the catalyst and the organic sewage after one electron beam irradiation, and if there are multiple electron beam irradiations, the contact time refers to the contact time after each electron beam irradiation and before the next irradiation; when step 1) and step 2) are performed simultaneously, the contact time is calculated from after the electron beam irradiation.

In the present invention, the combination of step 1) and step 2) may be repeated a plurality of times. Generally, the satisfactory effect can be achieved by irradiating 1 time for the sewage (the content of the high molecular organic compound is low) of a general sewage treatment plant. For sewage with particularly high content of the high molecular organic compound, multiple irradiation can be carried out, and the high molecular organic compound can be effectively degraded into small molecular substances which are easy to treat within 3 times.

In the present invention, the catalyst includes an active metal element selected from at least one of alkaline earth metals, transition metals, and the like.

Preferably, the active metal element is at least one selected from magnesium, aluminum, transition metals of periods 4 to 5, and the like.

In the present invention, the active metal element is present in an insoluble solid form. The term "insoluble" refers to insoluble in water, preferably both insoluble in water and in organic solvents. The insoluble solid of the active metal element may be at least one of a simple substance, an alkali, a salt, a metal oxide, and the like of the active metal element.

Further investigation revealed that the following preferred specific catalysts, step 2) used catalyst, may be selected from the first catalyst, the second catalyst or a combination thereof. The specific components of the first catalyst and the second catalyst will be described in detail hereinafter, respectively.

The first catalyst and the second catalyst can be used alone or in combination to achieve good effect of degrading high molecular organic compounds (such as molecular weight of more than 2KDa and even more than 5 KDa).

For example:

according to a first embodiment, said step 2) comprises: and contacting the organic sewage with a first catalyst.

According to a second embodiment, said step 2) comprises: and contacting the organic sewage with a second catalyst.

According to a third embodiment, said step 2) comprises: and contacting the organic sewage with a mixed catalyst of a first catalyst and a second catalyst.

According to a fourth embodiment, said step 2) comprises: and sequentially contacting the organic sewage with the first catalyst and the second catalyst, wherein the contacting is performed firstly with the first catalyst and then with the second catalyst, or the contacting is performed firstly with the second catalyst and then with the first catalyst, or the contacting is performed alternately for a plurality of times. In this embodiment, one or more electron beam irradiations may be inserted between the catalysts.

The amount of the catalyst can be adjusted within a wide range according to the specific sewage composition.

The total dosage of the first catalyst and/or the second catalyst can be 0.01-5 g, preferably 100-500 mg, relative to each L of sewage containing 1000mg/L of macromolecular organic matters with molecular weight more than 5 KDa. The amount is an amount that ensures the effect, but in practical use, an excessive amount of catalyst is generally spread in the system to cope with a long-term operation.

The first catalyst will be described below.

The first catalyst comprises a first carrier and a modification metal loaded on the first carrier; wherein the modified metal comprises at least one of Al, Ni, Co, Cu, Mn and the like.

Preferably, the modifying metal is selected from two or three of Co, Cu and a first combination, wherein the first combination is Ni and/or Mn. In the first combination, Ni and Mn may be present alone or in combination, and when present together, the molar ratio of Ni to Mn may be selected within a wide range, for example, 1: 0.01 to 100. The co-existing form can produce good synergistic effect, and further improve the degradation efficiency.

According to a specific embodiment, the modifying metal is Co, Cu and two of the first combination at a molar ratio of 1: 0.2-5.

According to another embodiment, the modified metal comprises Co, Cu and the first combination at a molar ratio of 1: 0.1-10, more preferably 1: 0.5-2.

Preferably, the loading amount of the modified metal in the first catalyst is 0.1-5 wt%, preferably 1.5-2.5 wt%. The weight is based on the weight of the metal simple substance. The presence of these metals may be determined according to the specific preparation process, and may include simple substances, and various oxides, salts (e.g., sulfate), and the like. The presence does not significantly affect the catalytic effect, and preferably 50 mol% or more is present in the elemental form.

Preferably, the metal particles have an average diameter of 1 to 100nm, preferably 2 to 10 nm.

In order to provide a catalytic environment for the modified metal, the first carrier is preferably a carrier with a relatively proper specific surface area in a relatively large range, and is preferably a carrier with a specific surface area of 1-1000 m²Preferably 200 to 500 m/g²/g。

For example, the first vector may be selected from, but is not limited to: activated carbon, alumina porous ceramic, In₂O₃Porous solids such as nanotubes, carbon nanotubes, zeolites, graphene, and the like. Preferably, the first carrier includes In₂O₃Hollow nanotubes.

Preferably, the In₂O₃The specific surface area of the hollow nanotube is 20-500 m²A concentration of 50 to 200m²(ii) in terms of/g. Preferably, the In₂O₃The average diameter of the hollow nanotubes is 20nm to 10 μm, preferably 400nm to 1 μm. Preferably, the In₂O₃The average length of the hollow nanotubes is 100nm to 10 μm, preferably 500nm to 5 μm.

The carrier is In₂O₃The first catalyst of the hollow nanotube can be prepared by the following method:

(a1) preparing an indium sacrificial template;

(a2) calcining the indium sacrificial template to obtain In₂O₃A hollow nanotube;

(a3) putting the In₂O₃Hollow nano-meterThe tube, metal source and reducing agent are contacted and the resulting material is calcined.

In step (a1), the indium sacrificial template may be commercially available MIL-68(In) or may be obtained by a preparation process, for example, including: the indium salt is used as a raw material and is prepared by a solvothermal method.

In the step (a1), preferably, the process of preparing the indium sacrificial template comprises: carrying out hydrothermal reaction on a mixed material of indium salt, phthalic acid and N, N-Dimethylformamide (DMF).

Preferably, the dosage ratio of the indium salt, the phthalic acid and the N, N-dimethylformamide is (0.3-0.5 g): 0.15-0.25 g): 4-6 mL, and more preferably (0.35-0.45 g): 0.18-0.22 g): 4.5-5.5 mL.

The hydrothermal reaction can be carried out under normal pressure, and therefore the temperature of the hydrothermal reaction is about 100 ℃.

The concentration of the indium salt in the aqueous solution of the hydrothermal reaction is, for example, 0.01 to 0.15 g/mL.

Preferably, the time of the hydrothermal reaction is 18-30 h, and more preferably 20-28 h.

The indium salt may be an inorganic salt of various kinds of indium, for example, indium nitrate.

The phthalic acid is, for example, terephthalic acid and/or isophthalic acid, preferably terephthalic acid.

In step (a2), the calcination process comprises a temperature-raising stage and a stabilizing stage; wherein the temperature raising stage comprises: the temperature rise rate is 1-15 ℃/min (preferably 3-8 ℃/min), and the temperature end point is 400-600 ℃ (preferably 450-550 ℃); the stabilization phase comprises: keeping the temperature for 1-3 h (preferably 1.5-2.5 h) at 400-600 ℃ (preferably 450-550 ℃).

Preferably, the method of the present invention further comprises: the indium sacrificial template is pre-fired under vacuum conditions prior to calcination. By the operation of this pre-firing, the obtained In can be made₂O₃The hollow nanotubes have a more uniform size distribution.

Preferably, the pre-sintering conditions comprise that the vacuum degree is 100-150 Pa, the temperature is 100-150 ℃, and the time is 8-16 h; more preferably, the burn-in conditions include: the vacuum degree is 110-130 Pa, the temperature is 110-130 ℃, and the time is 10-14 h.

In the step (a3), the In₂O₃The weight ratio of the hollow nanotube, the metal source and the reducing agent in terms of the metal simple substance is 100 mg: 10-30 mmol: 50-150 mmol, and more preferably 100 mg: 12-25 mmol: 80-120 mmol.

In step (a3), preferably, the contacting comprises: firstly, In is₂O₃After contacting the hollow nanotubes with the metal source for a period of time, contacting with the reducing agent. Preferably, the In is first introduced₂O₃The hollow nanotube is contacted with the metal source for 0.5-3 h (preferably 0.8-1.5 h).

Preferably, the conditions of the calcination include: the roasting temperature is 300-500 ℃, and the roasting time is 3-5 h; more preferably, the conditions of the calcination include: the roasting temperature is 350-450 ℃, and the roasting time is 3.5-4.5 h.

The metal source is a water-soluble salt of a metal element, such as a chloride salt, a nitrate salt, a sulfate salt, or the like. For example, the nickel source may be selected from NiSO₄、NiCl₂And Ni (NO)₃)₂Etc., preferably NiCl₂。

The metal source may be a metal source corresponding to a metal selected from at least one of Ni, Co, Cu, Mn, and the like. The particular choice and molar ratio may be determined according to the desired choice and molar ratio of the modifying metal in the first catalyst according to the first aspect of the invention.

Preferably, the reducing agent is selected from NaBH₄At least one of tannic acid, tetrabutylammonium borohydride and the like, preferably NaBH₄。

The second catalyst will be described below.

The second catalyst comprises a multi-metal oxygen-containing material, the multi-metal oxygen-containing material comprises a plurality of metal elements and oxygen elements, and the plurality of metal elements comprise a main metal element and an optional auxiliary metal element; the main metal element comprises at least one of metal elements A, B and C, wherein the metal element A is magnesium and/or calcium, the metal element B is at least one of titanium, vanadium, chromium, manganese, molybdenum, tungsten and the like, and the metal element C is at least one of iron, cobalt, nickel, copper, zinc and the like.

In the present invention, the main metal element may be one, two or three of the metal elements A, B and C. And the metal elements A, B and C may each independently be one element or a combination of elements.

According to a specific embodiment, the metal element A is Mg or Ca, for example, Mg and Ca are combined at a molar ratio of 1: 0.1-0.4.

In the invention, the metal element B is from IVB group, VB group, VIB group and VIIB group in the periodic table, and the metal element B is close to the metal element B in position in the periodic table and has similar properties. Although Mn is mainly exemplified in the present application, it is expected that the titanium, vanadium, chromium, molybdenum and tungsten of the metal element B can also achieve substantially equivalent effects.

According to a specific embodiment, the metal element B contains at least Mn, and Mn accounts for at least 60 mol% of the metal element B; for example, Mn, or a combination of Mn and Co at a molar ratio of 1: 0.1-0.4.

In the invention, the metal element C is from VIII group, IB group and IIB group in the periodic table, and the metal element C is close to the metal element C in position in the periodic table and has similar properties. Although Cu is mainly exemplified in the present application, it is expected that the iron, cobalt, nickel, copper, zinc, palladium, platinum, silver and gold of the metal element C can also achieve substantially equivalent effects.

According to a specific embodiment, the metallic element C contains at least Cu, and Cu represents at least 60 mol% of the metallic element B; for example, Cu, or the combination of Cu and Ni at a molar ratio of 1: 0.1-0.4.

The metal elements A, B and C may be present in the primary metal element in a ratio of: the content of the metal element A is 10 to 90 mol%, the content of the metal element B is 0 to 80 mol%, the content of the metal element C is 0 to 80 mol%, and the content of the metal element B and the content of the metal element C are not 0 at the same time and the total content is not less than 10 mol% based on the total mol amount of the main metal element.

Preferably, the content of the metal element a is 20 to 70 mol%, the content of the metal element B is 0 to 80 mol%, the content of the metal element C is 0 to 80 mol%, and the content of the metal element B and the content of the metal element C are not 0 at the same time and the total content is not less than 30 mol%, based on the total molar amount of the main metal elements.

According to a specific embodiment, the metal elements A, B and C are present simultaneously, and the molar ratio of the metal elements A, B to C is preferably 1: 0.1-10 based on the total ratio; preferably 1: 0.2-3: 0.2-2.

For example, according to a specific embodiment, said a is Mg and/or Ca, said B is Mn, said C is Cu and/or Ag; and the molar ratio of A, B to C is 1: 0.2-3: 0.2-2.

Preferably, the metal elements B and C are simultaneously present, and the molar ratio of the sum of the mole numbers of the metal elements B and C to the metal element A is (1-4): 1, and more preferably (2-3): 1.

In the present invention, the presence of the secondary metallic element is optional, i.e., the multi-metal oxygen-containing material may or may not include the secondary metallic element.

When the secondary metal element is included, it is ensured that the molar amount of the main metal element is 70% or more, preferably 80% or more, based on the total molar amount of the polyvalent metal elements.

According to a specific embodiment of the present invention, the plurality of metal elements includes a secondary metal element. It is known that certain specific metal elements have a specific effect on specific compounds, so that in the presence of these specific compounds, a person skilled in the art can add the corresponding specific metal elements as auxiliary metal elements on the basis of the main metal elements of the present invention. The catalytic effect can be further enhanced on the basis of the original effectiveness.

According to a preferred embodiment, the secondary metal element is a rare earth element. Preferably, the auxiliary metal element is at least one selected from lanthanum, cerium, praseodymium and the like. Preferably, the molar weight ratio of the auxiliary metal element to the main metal element is (0.1-0.5): 1.

Preferably, the multi-metal oxygen-containing material is prepared by a method comprising the following steps:

(b1) coprecipitating soluble salts of various metal elements in an alkaline environment to obtain a multi-metal material;

(b2) and oxidizing the multi-element metal material.

In step (b1), the method of co-precipitation may be performed in a manner conventional in the art. The anionic component in the polymetallic material formed by the co-precipitation is not particularly limited, and includes, but is not limited to [ OH [ ]]、[CO₃]、[SO₄]And the like. The choice of anions in the first aspect of the invention is not particularly limited, as they will often yield similar oxide products upon oxidation reactions in forming the multinary metal oxygen-containing materials of the invention.

It should be noted that, in the present invention, the term "multi-metal material" specifically refers to the material obtained in the step (b 1); the term "multi-metal oxygen-containing material" refers specifically to the second catalyst used in the degradation process of the present invention. These two terms do not have the upper and lower relationships conventionally understood in the art in the present invention.

In step (b2), the oxidation may be carried out by conventional oxidation methods in the art, such as calcination, sintering, solvent heating, etc.; preferably by calcination.

The multi-metal oxygen-containing material can be obtained by oxidation reaction of the multi-metal material obtained in the step (b 1). Therefore, the multi-metal oxygen-containing material necessarily contains oxygen atoms, but the invention is not limited by the existence of elements except the multi-metal elements and the oxygen atoms, which mainly depends on the existence form of the anionic groups in the multi-metal material after the oxidation reaction. Under the mutual synergy of a plurality of specific metal elements, the catalyst can already play a good catalytic effect in a free radical environment generated by an electron beam.

According to a specific embodiment, the second catalyst may further comprise a second support, i.e. the multi-metal oxygen-containing material is supported on the second support. It should be noted that, in the present invention, when the amount of the second catalyst is calculated, the amount of the multi-metal oxygen-containing material is calculated only, and the amount of the carrier is not calculated.

Preferably, the second support is alumina; such as a porous alumina substrate. Preferably, the weight ratio of the second carrier to the multi-metal oxygen-containing material loaded thereon is (1-100): 1, preferably (10-60): 1.

According to one embodiment, in the electron beam catalytic unit, the organic wastewater passes through a flow channel irradiated with an electron beam, and a catalyst-supporting member is disposed on the flow channel.

Preferably, the retention time of the organic sewage in the electron beam catalyst unit is 1 s-20 min, and preferably 0.5-5 min.

Through the treatment of the electron beam catalytic unit, high-concentration, difficult-degradation and long-chain high-molecular organic compounds in the sewage can be effectively degraded, so that the sewage treatment efficiency is greatly improved.

The electron beam catalytic unit of the invention can be matched with various operation modes of sewage treatment.

Preferably, a biochemical unit is disposed after the electron beam catalytic unit. At least one of anaerobic, facultative and aerobic biochemical treatment processes can occur in the biochemical unit.

Preferably, a facultative/aerobic biochemical reaction is performed in the biochemical unit.

Preferably, the organic sewage stays in the biochemical unit for 2-20 hours.

The organic sewage treatment process of the invention can also comprise other treatment procedures, such as Fenton, ozone catalytic oxidation, ultrafiltration, nanofiltration, reverse osmosis and the like. In fact, the organic sewage treatment process can achieve satisfactory water treatment effect only by matching the electron beam catalytic unit with a conventional biochemical unit.

According to a specific embodiment, the organic sewage treatment process comprises passing organic sewage through a coarse filtration unit, the electron beam catalysis unit, the biochemical unit and a fine filtration unit in sequence.

An operation of physically separating large particulate solid matter in the organic sewage is performed in the coarse filtration unit. The rough filtration unit may be carried out according to a conventional physical separation pretreatment operation in the sewage treatment process, such as sedimentation, air flotation, centrifugation, filtration, magnetic separation, and the like.

The fine filter unit is used for the final physical separation of small-particle solid matter, for example, sand filtration can be carried out.

Through the treatment of the four units, the organic sewage treatment process can lead the sewage of the conventional sewage treatment plant to reach the standard and discharge, and even lead the sewage with higher content of macromolecular organic compounds which is difficult to treat by the common sewage treatment plant to reach the standard and discharge.

Compared with the existing sewage treatment process, the process of the invention at least has the following advantages:

(1) the invention can effectively degrade high molecular organic compounds;

(2) the invention has fast degradation speed, and can achieve satisfactory degradation effect within 10min of the retention time of the electron beam catalysis unit;

(3) the method is simple to operate, has low requirements on reaction environment, and does not need to build complex processing unit equipment;

(4) the process of degrading the high molecular compound does not need extra addition of medicaments and does not bring secondary pollution;

(5) the high molecular compound is degraded to be just used as a nutrient substance for biochemical treatment, and a carbon source is not required to be additionally added;

(6) the method has the advantages of simple process, few steps and short overall time consumption.

The endpoints of the ranges and any values disclosed in the present application are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual values, and between the individual values may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

Detailed Description

The present invention will be described in detail below by way of examples. The described embodiments of the invention are only some, but not all embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The reagents used in the following examples are all commercially available analytical reagents unless otherwise specified.

Preparation A1

This set of preparation examples is illustrative of the first catalyst of the present invention.

Preparation A1a

(1) Weighing 5ml of DMF solution in a hydrothermal reaction kettle, adding 0.4g of indium nitrate and 0.2g of terephthalic acid, reacting at 100 ℃ for 24 hours, and centrifugally drying to obtain an indium sacrificial template;

(2) carrying out heat treatment on the indium sacrificial template obtained in the step (1) for 12h under the vacuum condition that the vacuum degree is 120Pa and the temperature is 120 ℃; then transferring the mixture into a muffle furnace, raising the temperature to 500 ℃ at the temperature rise rate of 5 ℃/min, and continuing calcining for 2h to obtain In with a hollow structure₂O₃A nanotube;

(3) 100mg of In were weighed₂O₃Adding 10mL of deionized water, performing ultrasonic treatment for 10min, uniformly dispersing the sample, adding 10mL of 25mmol of mixed solution of cobalt, copper, nickel and manganese chloride salts with the molar ratio of 1: 1.5: 0.7: 0.3, stirring for 1h, and adding 100mL of 1mol/L reducer NaBH₄(ii) a The obtained material is placed in a roasting furnace with the temperature of 400 ℃ for roasting and activation for 4 hours to obtain a powdery composite catalyst, namely the second catalyst of the inventionA catalyst.

Preparation A1b

Referring to preparation example A1a, except that in step (3), the chloride salt mixed solution of cobalt, copper, nickel and manganese was changed to 10mL of a 25mmol total chloride salt mixed solution of cobalt and copper at a molar ratio of 1: 1. Finally preparing the catalyst.

Preparation A1c

Referring to preparation example A1a, except that in step (3), the chloride salt mixed solution of cobalt, copper, nickel and manganese was changed to 10mL of a 25mmol in total chloride salt mixed solution of cobalt and manganese at a molar ratio of 1: 1. Finally preparing the catalyst.

Preparation A2

This set of preparation examples is illustrative of the second catalyst of the present invention.

Preparation A2a

(1) 1mol of Mg (NO) is weighed out separately₃)₂1mol of MnSO₄And 1mol of Cu (NO)₃)₂Dissolving the mixed solution in 500mL of deionized water to obtain a mixed metal salt solution; adding NaOH solution serving as a precipitator into the mixed metal salt solution, slowly adding the NaOH solution to ensure that metal ions in the solution completely precipitate within 2 hours, and continuously stirring at room temperature for 24 hours; washing and filtering the obtained solid precipitate with deionized water for 3 times, and drying at 80 ℃ to obtain a tawny Mg-Mn-Cu ternary metal material;

(2) and (2) placing the ternary metal material obtained in the step (1) in a muffle furnace, heating to 500 ℃ at the speed of 2 ℃/min, and then continuously roasting for 2h at the temperature of 500 +/-10 ℃ to obtain the Mg-Mn-Cu ternary metal oxygen-containing material, namely the second catalyst.

Preparation A2b

With reference to preparation A2a, except that in step (1), Mg (NO) is added₃)₂Replacing with Mg (NO) at the same molar ratio of 1: 0.3 based on total molar weight₃)₂And Ca (NO)₃)₂Mixing MnSO₄Replacing with MnSO at the same molar ratio of 1: 0.1 based on total molar weight₄And CoSO₄Adding Cu (NO)₃)₂Replacing with Cu (NO) at the same molar ratio of 1: 0.4 based on total molar weight₃)₂And Ni (NO)₃)₂. Finally preparing the catalyst.

Preparation A2c

Referring to preparation A2a, except that in step (1), MnSO₄Replacement by the same molar amount of TiOSO₄Adding Cu (NO)₃)₂By substitution with the same molar amount of Co (NO)₃)₂. Finally preparing the catalyst.

Preparation A2d

Reference is made to preparation A2a, except that, in step (1), no MnSO is added₄. Finally obtaining the binary metal oxygen-containing material catalyst.

The following group B examples are provided to illustrate the wastewater treatment process of the present invention.

Example B1a

The sewage to be treated (water quality indexes are shown in table 1) sequentially passes through the following units:

(1) a coarse filtration unit: carrying out integrated type super-magnetic separation to remove solid matters in the sewage;

(2) an electron beam catalytic unit: flowing sewage in a flow channel, performing electron beam irradiation (the energy is 2.0MeV, the beam intensity is 100mA) on the sewage flowing through a point A, then reaching the point B after 5s, paving catalyst particles A1a at the bottom of the flow channel from the point B, reaching the point C after 20s, paving catalyst particles A2a at the bottom of the flow channel from the point C, and leaving an electron beam catalysis unit after 30 s;

(3) a biochemical unit: the facultative/aerobic biochemical reactor is provided with an enzyme floating filler and stays for 10 hours;

(4) a fine filtering unit: and (4) enabling the sewage to enter a sand filter tank to remove residual pollutants.

And collecting water at the outlet of the fine filtering unit to be detected.

Examples B1B-B1c

The procedure is as in example B1a, except that in step (2) the catalyst particles A1a are replaced by catalyst particles A1B and A1c, respectively, of the same mass.

And collecting water at the outlet of the fine filtering unit to be detected.

Example B1d

The procedure is as in example B1a, except that in step (2), catalyst particles A1a are deposited at the bottom of the flow channel starting from point B and leaving the electron beam catalytic unit after 3 min.

And collecting water at the outlet of the fine filtering unit to be detected.

Example B2a

The procedure is as in example B1a, except that in step (2), catalyst particles A2a are deposited at the bottom of the flow channel starting from point B and leaving the electron beam catalytic unit after 3 min.

And collecting water at the outlet of the fine filtering unit to be detected.

Examples B2B-B2d

The procedure is as in example B2a, except that in step (2), the catalyst particles A1a are replaced by the same mass of catalyst particles A2B-A2d, respectively.

And collecting water at the outlet of the fine filtering unit to be detected.

Example B3

This set of examples is used to illustrate the effect of operating parameters.

Example B3a

The procedure is as in example B1a, except that in step (2) the flow rate of the contaminated water is varied such that it takes 2min from point B to point C and 3min from point C to the point where it leaves the electron beam catalytic unit.

And collecting water at the outlet of the fine filtering unit to be detected.

Example B3B

The procedure is as in example B1a, except that in step (2) the flow rate of the contaminated water is varied such that 10s is required from point B to point C and 10s is required from point C to exit the electron beam catalytic unit.

And collecting water at the outlet of the fine filtering unit to be detected.

Comparative example BD1

Proceeding as in example B1a, with the exception that the electron beam catalytic unit is replaced by an ozone catalytic oxidation unit, in particular in which:

adjusting the pH value of the sewage to 5.6, and controlling the temperature to be 15 ℃; ozone is led into the ozone catalytic oxidation unit to lead the ozone to be oxidizedThe concentration of (2) is 9mg/L, then NiFe is added₂O₄，NiFe₂O₄The mass ratio of ozone to ozone is 15: 1, and the treatment time is 30 min; NiFe recovery by magnetic field with magnetic field intensity of 0.1T₂O₄And absorbing the ozone tail gas by using 5 percent KI solution to finish the catalytic oxidation treatment process of the ozone.

And collecting water at the outlet of the fine filtering unit to be detected.

Comparative example BD2

The procedure is as in example B1a, except that, in step (2), no catalyst prepared in the preparation examples is used, but only electron beam irradiation is carried out.

And collecting water at the outlet of the fine filtering unit to be detected.

Comparative example BD3

The procedure is as in example B1a, except that, in step (2), no electron beam irradiation is carried out.

And collecting water at the outlet of the fine filtering unit to be detected.

Test example

The water quality index of the sewage to be treated used in the examples is shown in Table 1. In addition, Table 1 also shows the classification index according to the GB18918-2002 discharge Standard for pollutants from municipal wastewater treatment plants.

TABLE 1

The water quality of the treated water obtained in the above examples and comparative examples was measured, and the results of classification are shown in Table 2 by comparing the indexes shown in Table 1. And detecting the content (mg/L) of the macromolecular organic matters with the molecular weight higher than 5KDa in the water, and recording the content in the column of 5 KDa.

TABLE 2

	5KDa content mg/L	Grading the results
			Waste water	1536	---
B1a	Not detected	First order A
			B1b	Not detected	First order A
B1c	Not detected	First order A
			B1d	Not detected	First order A
B2a	Not detected	First order A
			B2b	Not detected	First order A
B2c	Not detected	First order A
			B2d	Not detected	First order A
B3a	Not detected	First order A
			B3b	45	Stage B
BD1	328	Second stage
			BD2	826	Is worse than the third-level standard
BD3	1384	Is worse than the third-level standard

As can be seen from tables 1 and 2, the wastewater treatment process of the present invention can effectively degrade the high molecular organic compounds in a short time, and the water quality can reach the first-class standard as a whole; the treatment time of the method is obviously shorter than that of a comparison group, and the treatment effect is obviously better than that of the comparison group.

The preferred embodiments of the present invention are described above in detail. However, the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the protection scope of the invention.

Claims

1. A treatment process for treating organic sewage by electron beam irradiation and a catalyst is characterized by comprising an electron beam catalysis unit, wherein organic matters are degraded in the electron beam catalysis unit, and the method comprises the following steps:

(1) carrying out electron beam irradiation on the organic sewage;

(2) contacting the organic sewage with a catalyst;

wherein, the step (1) and the step (2) are carried out simultaneously or successively after an interval time which is less than or equal to 1 min;

the catalyst comprises an active metal element selected from at least one of alkaline earth metals and transition metals, the active metal element being present in an insoluble solid form, and optionally a support.

2. The process of claim 1, wherein the conditions of electron beam irradiation include: the energy of electron beam irradiation is 1.0-3.0 MeV, and the beam intensity is 80-200 mA;

preferably, the energy of electron beam irradiation is 1.2-2.8 MeV, and the beam intensity is 100-140 mA.

3. The process according to claim 1, wherein in the step (2), the organic wastewater is contacted with the catalyst for 1 s-10 min;

preferably, the contact time is 0.5-5 min.

4. The process according to claim 1, wherein the active metal element is selected from at least one of magnesium, aluminum and transition metals of periods 4-5;

preferably, the insoluble solid of the active metal element is at least one of a simple substance, an alkali, a salt, a metal oxide, and the like of the active metal element.

5. The process according to claim 1, wherein the catalyst is a first catalyst and/or a second catalyst;

the first catalyst comprises a first carrier and a modification metal loaded on the first carrier; the modified metal comprises at least one of Al, Ni, Co, Cu and Mn; preferably, the first carrier is selected from In₂O₃At least one of a nanotube, activated carbon, carbon nanotube, alumina ceramic, zeolite, and graphene porous solid;

the second catalyst comprises a multi-metal oxygen-containing material, the multi-metal oxygen-containing material comprises a plurality of metal elements and oxygen elements, and the plurality of metal elements comprise a main metal element and an optional auxiliary metal element; the main metal element comprises at least one of metal elements A, B and C, wherein the metal element A is magnesium and/or calcium, the metal element B is at least one of titanium, vanadium, chromium, manganese, molybdenum and tungsten, and the metal element C is at least one of iron, cobalt, nickel, copper and zinc.

6. The process of claim 1, wherein in the step (2), the specific method for contacting the organic wastewater with the catalyst comprises: contacting the organic wastewater with a first catalyst; or contacting the organic sewage with a second catalyst; or contacting the organic sewage with a mixed catalyst of a first catalyst and a second catalyst; or the organic sewage is contacted with the first catalyst and the second catalyst sequentially, wherein the contacting is carried out firstly with the first catalyst and then with the second catalyst, or the contacting is carried out firstly with the second catalyst and then with the first catalyst, or the contacting is carried out alternately for a plurality of times.

7. The treatment process of organic sewage by using electron beam irradiation and catalyst as claimed in claim 1 or 5, wherein the organic sewage is sewage containing 1000mg/L of macromolecular organic substance with molecular weight greater than 5 KDa; the total dosage of the first catalyst and/or the second catalyst is 0.01-5 g relative to 1L of organic sewage.

8. The process of claim 1, wherein a biochemical unit is disposed before or after the electron beam catalysis unit.

9. The treatment process of the organic sewage by the electron beam irradiation and the catalyst as claimed in any one of claims 1 to 8, wherein the treatment process of the organic sewage comprises passing the organic sewage through a coarse filtration unit, an electron beam catalysis unit, a biochemical unit and a fine filtration unit.