Method and device for treating peroxymonosulfate water excited by alkali-reinforced copper-based material

Abstract

The invention provides a water treatment method and device using an alkali-reinforced copper-based material to excite peroxymonosulfate, and relates to the technical field of wastewater treatment.The method comprises the steps that an alkali agent, the copper-based material and peroxymonosulfate are added into water to be treated; the alkaline agent is sodium hydroxide and / or potassium hydroxide; the copper-based material is copper oxide and / or copper sulfide. The method provided by the invention has the advantages of excellent pollutant treatment effect, mild reaction conditions, simple process flow, environmental protection, energy saving, easy recovery and recycling and the like, and realizes the purposes of small dosage of the oxidant and the catalyst, high utilization rate of the oxidant, small dissolution amount of metal ions and up-to-standard pH of effluent.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and in particular to a method and device for treating wastewater by activating peroxymonosulfate with an alkali-strengthened copper-based material. Background Art

[0002] With the accelerated advancement of China's industrialization process and the leapfrog development of science and technology, the problem of water environmental pollution has shown a new evolution trend. In recent years, a class of new pollutants different from traditional refractory organic pollutants has gradually emerged. They frequently appear in the effluents of multiple sewage treatment plants across the country and ultimately enter the natural water system. These pollutants mainly cover four typical categories: persistent organic pollutants, endocrine disruptors, antibiotics and resistance genes, and microplastics, and have prominent characteristics such as strong bioaccumulation, significant environmental persistence, and complex ecological toxicity.

[0003] The advanced oxidation technology based on peroxymonosulfate has the core advantages of low oxidant cost, safe and stable storage and transportation, but generally has technical bottlenecks such as complex preparation process of efficient catalysts, excessive dosage of oxidants and catalysts, low utilization rate of oxidants, metal ion dissolution, and overly acidic effluent, which limit its engineering application. Existing water treatment technologies have many above-mentioned technical defects in dealing with such new pollutants, and there is an urgent need to develop an innovative water treatment technology system with high removal performance to meet the urgent needs of environmental governance. Summary of the Invention

[0004] (I) Technical Problems to be Solved

[0005] In view of this, the present invention provides a method and device for treating wastewater by activating peroxymonosulfate with an alkali-strengthened copper-based material, which are used to solve technical problems such as excessive dosage of oxidants and catalysts in the peroxymonosulfate treatment system, low utilization rate of oxidants, metal ion dissolution, and overly acidic effluent.

[0006] (II) Technical Solutions

[0007] The technical solutions of the present invention are realized as follows:

[0008] One aspect of the embodiments of the present disclosure provides a method for treating wastewater by activating peroxymonosulfate with an alkali-strengthened copper-based material, the method comprising: adding an alkali agent, a copper-based material, and peroxymonosulfate to water to be treated for reaction.

[0009] The alkali agent is sodium hydroxide and / or potassium hydroxide.

[0010] The copper-based material is copper oxide and / or copper sulfide.

[0011] According to an embodiment of the present invention, the peroxymonosulfate is one or a combination of two or more of potassium peroxymonosulfate, sodium peroxymonosulfate, and calcium monopersulfate.

[0012] According to an embodiment of the present invention, the alkali agent and peroxymonosulfate are added in the form of a solution, wherein the molar concentration ratio of hydroxide ions to peroxymonosulfate is 0.5 to 2.5:1.

[0013] According to an embodiment of the present invention, the alkali agent and peroxymonosulfate are added in the form of a solution, wherein the molar concentration ratio of hydroxide ions to peroxymonosulfate is 1 to 2:1.

[0014] According to an embodiment of the present invention, the alkali agent and peroxymonosulfate are added in the form of a solution, wherein the molar concentration ratio of hydroxide ions to peroxymonosulfate is 1.5:1.

[0015] According to an embodiment of the present invention, the peroxymonosulfate is potassium peroxymonosulfate.

[0016] According to an embodiment of the present invention, the copper-based material is copper oxide, and the dosage of the copper oxide is 25 to 200 mg / L.

[0017] According to an embodiment of the present invention, the copper-based material is copper oxide, and the dosage of the copper oxide is 50 to 150 mg / L.

[0018] According to an embodiment of the present invention, the copper-based material is copper oxide, and the dosage of the copper oxide is 100 mg / L.

[0019] According to an embodiment of the present invention, the copper-based material is copper sulfide, and the dosage of the copper sulfide is 15 to 100 mg / L.

[0020] According to an embodiment of the present invention, the copper-based material is copper sulfide, and the dosage of the copper sulfide is 25 to 75 mg / L.

[0021] According to an embodiment of the present invention, the copper-based material is copper sulfide, and the dosage of the copper sulfide is 50 mg / L.

[0022] According to an embodiment of the present invention, the water to be treated contains free radical-degradable pollutants.

[0023] According to an embodiment of the present invention, the free radical-degradable pollutants include one or a combination of two or more of sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine.

[0024] Another aspect of the embodiments of the present disclosure provides an apparatus for treating water by activating peroxymonosulfate with an alkali-strengthened copper-based material. The apparatus includes: a reactor for accommodating an alkali agent, peroxymonosulfate, a copper-based material, and water to be treated, and for carrying out reactions; an alkali agent adding device communicating with the reactor for adding the alkali agent into the reactor; a peroxymonosulfate adding device communicating with the reactor for adding peroxymonosulfate into the reactor; a copper-based material adding device communicating with the reactor for adding the copper-based material into the reactor; and a water to be treated adding device communicating with the reactor for adding the water to be treated into the reactor.

[0025] According to an embodiment of the present invention, the copper-based material adding device and the reactor are integrated. The copper-based material is pre-placed in the reactor.

[0026] (III) Beneficial effects

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] In the embodiments of the present invention, an alkali agent, a copper-based material, and peroxymonosulfate are simultaneously added to the wastewater to be deeply treated. The alkali agent and peroxymonosulfate act synergistically on the surface of the copper-based material. The copper-based material is affected by the strong alkali, and its surface changes. This surface change can activate the continuous degradation ability of the peroxymonosulfate system. The alkali in-situ strengthens the copper-based material to activate the peroxymonosulfate system. By in-situ adding the alkali agent and in-situ etching the copper-based material, active sites are continuously generated, enhancing the adsorption and activation of peroxymonosulfate, generating more abundant sulfate radicals and hydroxyl radicals, and achieving effective degradation of pollutants.

[0029] 1. Under the action of the alkali agent, a large number of hydroxyl groups are formed on the surface of copper oxide, which can induce the in-situ generation of abundant oxygen vacancies. Specifically, on the one hand, the coexistence of surface hydroxyl groups and oxygen vacancies produces a synergistic effect, which can significantly promote the adsorption and decomposition of peroxymonosulfate; on the other hand, the in-situ alkali etching to generate oxygen vacancies and surface hydroxyl groups is a process of active site regeneration, effectively solving the problem of copper oxide deactivation, and endowing the alkali-strengthened copper oxide with the ability to activate the peroxymonosulfate (OH - / CuO / PMS) system for continuous degradation.

[0030] 2. Under the action of the alkali agent, the unique S-S bond on the surface of copper sulfide is reductively broken. With the addition of peroxymonosulfate, the S-S bond is oxidized and restored. The above process accelerates the electron transfer and circulation rate of the reaction process, effectively promotes the regeneration of low-valent copper, realizes the efficient decomposition of peroxymonosulfate, and endows the alkali-strengthened copper sulfide with the ability to activate the peroxymonosulfate (OH - / CuS / PMS) system for continuous degradation.

[0031] 3. OH - / CuO / PMS and OH -In the / CuS / PMS system, under the in-situ alkali enhancement, peroxymonosulfate is efficiently decomposed on the surface of the copper-based material to generate active species mainly composed of free radicals, thereby completely removing sulfamethoxazole, ibuprofen, atrazine, quinoline or carbamazepine in water.

[0032] 4. The present invention has the advantages of excellent effect in treating new pollutants, mild reaction conditions, simple process flow, green environmental protection, energy saving, easy recovery and recycling, etc., and achieves the purpose of small dosage of oxidant and catalyst, high utilization rate of oxidant, small amount of metal ion dissolution and pH of effluent meeting the standard. It provides feasibility for deep treatment of wastewater, has good implementation operability, and can be widely promoted and applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings.

[0034] Figure 1 The scanning electron microscope images of copper oxide and copper sulfide used in the embodiments of the present invention are shown.

[0035] Figure 2 The X-ray diffraction patterns of copper oxide and copper sulfide used in the embodiments of the present invention are shown.

[0036] Figure 3 The sulfamethoxazole degradation effect diagram of each system in Example 1 of the present invention is shown.

[0037] Figure 4 The OH and SO4 captured by DMPO in different systems according to Example 1 of the present invention are shown. •− EPR spectrum of .

[0038] Figure 5 The pH changes during the reaction of different systems in Example 1 of the present invention are shown.

[0039] Figure 6 The OH under different conditions in Example 2 of the present invention is shown. - / CuO / PMS system sulfamethoxazole degradation effect diagram.

[0040] Figure 7 The OH under different conditions in Example 3 of the present invention is shown. - / CuS / PMS system sulfamethoxazole degradation effect diagram.

[0041] Figure 8 It shows that OH in Example 4 according to the present invention - / CuO / PMS system and OH -Degradation effect diagrams of ibuprofen, atrazine, quinoline and carbamazepine in the / CuS / PMS system.

[0042] Figure 9 Schematically shows the method and device for treating water by activating peroxymonosulfate with an alkali-strengthened copper-based material according to Embodiment 6 of the present invention.

[0043] Figure 10 Schematically shows a schematic diagram of a continuous flow device for sulfamethoxazole under the background of long-term treatment of secondary effluent from a sewage treatment plant according to Embodiments 7 and 8 of the present invention.

[0044] Figure 11 Shows OH according to Embodiment 7 of the present invention - Degradation effect diagram of sulfamethoxazole in the / CuO / PMS system for long-term treatment of secondary effluent from a sewage treatment plant.

[0045] Figure 12 Shows OH according to Embodiment 8 of the present invention - Degradation effect diagram of sulfamethoxazole in the / CuS / PMS system for long-term treatment of secondary effluent from a sewage treatment plant. Detailed implementation manners

[0046] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following further elaborates on the present invention in detail with reference to specific embodiments and the accompanying drawings.

[0047] The terms used herein are merely for describing specific embodiments and are not intended to limit the present invention. The terms "including", "comprising", etc. used herein indicate the presence of the described features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0048] The advanced oxidation technology based on peroxymonosulfate has the core advantages of low oxidant cost, safe and stable storage and transportation. It generates multiple reactive oxygen species mainly composed of sulfate radicals through activation regulation, and shows high efficiency and adaptability in the treatment of refractory pollutants. This technology has the characteristics of simple device, low energy consumption and flexible operation, and is especially suitable for complex wastewater systems. The transition metal activation system is the mainstream path, but generally faces technical bottlenecks such as excessive dosage of oxidant and catalyst, low utilization rate of oxidant, metal ion dissolution and over-acidic effluent, which limit its engineering application. It is urgent to achieve systematic breakthroughs through material strengthening and process optimization.

[0049] The present invention intends to construct sustainable active sites by in-situ addition of alkali agents, strengthen the performance of copper-based materials in activating peroxymonosulfate, construct an alkali in-situ strengthened copper-based material activating peroxymonosulfate system, and achieve efficient removal of new refractory pollutants in water.

[0050] Based on this, an embodiment of the present invention provides a water treatment method for activating peroxymonosulfate by an alkali in-situ enhanced copper-based material. In the embodiment of the present invention, an alkali agent, a copper-based material, and peroxymonosulfate are added to the water to be treated for reaction. The alkali agent is sodium hydroxide and / or potassium hydroxide; the copper-based material is copper oxide and / or copper sulfide. By in-situ addition of the alkali agent, in-situ etching of the copper-based material is carried out, continuously generating active sites, enhancing the adsorption and activation of peroxymonosulfate, and generating more abundant sulfate radicals and hydroxyl radicals. Thus, effective degradation of pollutants is achieved.

[0051] The above method has the advantages of mild reaction conditions, simple process flow, low cost, etc.

[0052] In some embodiments of the present invention, the alkali agent, the copper-based material, and peroxymonosulfate can be added to the water to be treated simultaneously. It should be noted that the so-called simultaneous addition to the water to be treated means continuous and compact in time, rather than being understood as limited to an absolutely small same time point. Only when the alkali agent, the copper-based material, and peroxymonosulfate are all added to the water to be treated, does the reaction of alkali-enhanced copper-based material activating peroxymonosulfate occur to produce the technical effect of this application. In some cases, two of the above alkali agent, copper-based material, and peroxymonosulfate can be added to the water to be treated first. However, since the reaction effect of alkali-enhanced copper-based material activating peroxymonosulfate cannot be produced, until the remaining third component is added to the water, at this time, since the three components are present in the water to be treated, the reaction of alkali-enhanced copper-based material activating peroxymonosulfate occurs to produce the technical effect of this application. In this case, it can also be understood that the reaction described in this application occurs only when the alkali agent, the copper-based material, and peroxymonosulfate coexist, that is, the so-called simultaneous addition in this application.

[0053] The degradation of pollutants by free radicals as mentioned in this application means that the pollutants are decomposed into harmless substances based on the strong oxidizing property of free radicals. The degradation of pollutants by free radicals as mentioned in this application can include sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine. The embodiments of the present invention can effectively remove sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine in water. By simultaneously adding an alkali agent, a copper-based material, and peroxymonosulfate to an aqueous solution containing sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine and stirring at room temperature, wherein the copper-based catalyst is the aforementioned copper oxide or copper sulfide, sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine is degraded.

[0054] The alkali in-situ enhanced copper-based material-activated peroxymonosulfate system adds alkali agents in-situ, etches the copper-based material in-situ, continuously generates active sites, enhances the adsorption and activation of peroxymonosulfate, produces more abundant sulfate radicals and hydroxyl radicals, and reacts with pollutants such as sulfamethoxazole, ibuprofen, atrazine, quinoline, or carbamazepine in water through hydroxylation, ketonization, decarboxylation, demethylation, side-chain decarboxylation, and aryl epoxidation reactions to achieve effective degradation of pollutants.

[0055] The embodiment of the present invention also provides a water treatment device for activating peroxymonosulfate with an alkali-enhanced copper-based material. The device includes: a reactor for accommodating an alkali agent, peroxymonosulfate, a copper-based material, and water to be treated, and for carrying out reactions; an alkali agent adding device communicated with the reactor for adding the alkali agent into the reactor; a peroxymonosulfate adding device communicated with the reactor for adding peroxymonosulfate into the reactor; a copper-based material adding device communicated with the reactor for adding the copper-based material into the reactor; and a water to be treated adding device communicated with the reactor for adding the water to be treated into the reactor. In some cases, one component can be added to the water to be treated or the reactor first, so the corresponding two adding devices can be combined in design. For example, the copper-based material adding device and the reactor can be combined into one, or the peroxymonosulfate adding device and the water to be treated adding device can be combined in design.

[0056] The embodiment of the present invention provides a method for constructing a continuous flow system by using an alkali in-situ enhanced copper-based material-activated peroxymonosulfate system to achieve long-term removal of sulfamethoxazole in the secondary effluent of a sewage treatment plant, including: fixing the copper-based material between layers of degreased cotton to make a reaction column; simultaneously introducing the secondary effluent containing an alkali agent and sulfamethoxazole and a peroxymonosulfate solution into the above reaction column through two pipelines, so that sulfamethoxazole in the final effluent is degraded.

[0057] The present invention will be further described below through specific embodiments. The above methods and applications of activating peroxymonosulfate with an alkali in-situ enhanced copper-based material are specifically described in the following embodiments. However, the following embodiments are only used to illustrate the present invention, and the scope of the present invention is not limited thereto.

[0058] Example 1:

[0059] Different systems (peroxymonosulfate (PMS), alkali agent (OH - ), copper-based material (CuO or CuS), OH - / PMS, CuO / PMS, CuS / PMS, OH - / CuO, OH - / CuS, OH - / CuO / PMS, OH -Removal effect of sulfamethoxazole (SMX) in the water to be treated by / CuS / PMS).

[0060] PMS system: Add peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0061] OH - system: Add an alkali agent to the aqueous solution containing sulfamethoxazole and react.

[0062] CuO system: Add CuO to the aqueous solution containing sulfamethoxazole and react.

[0063] CuS system: Add CuS to the aqueous solution containing sulfamethoxazole and react.

[0064] OH - / PMS system: Add an alkali agent and peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0065] CuO / PMS system: Add CuO and peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0066] CuS / PMS system: Add CuS and peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0067] OH - / CuO: Add an alkali agent and CuO to the aqueous solution containing sulfamethoxazole and react.

[0068] OH - / CuS system: Add an alkali agent and CuS to the aqueous solution containing sulfamethoxazole and react.

[0069] OH - / CuO / PMS system: Add an alkali agent, CuO and peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0070] OH - / CuS / PMS system: Add an alkali agent, CuS and peroxymonosulfate to the aqueous solution containing sulfamethoxazole and react.

[0071] Experimental conditions: In this example, potassium peroxymonosulfate (PMS) is specifically potassium hydrogen persulfate, and more specifically a composite salt of potassium hydrogen persulfate, where the mass fraction of potassium hydrogen persulfate is 42%; the alkali agent is sodium hydroxide, and the molar concentration ratio of sodium hydroxide to potassium hydrogen persulfate added is 1.5∶1. Specifically, the dosage of the medicament in the system containing CuO is 0.6 mM of the alkali agent, 0.4 mM of potassium hydrogen persulfate, and 100 mg / L of CuO; the dosage of the medicament in the system containing CuS is 0.3 mM of the alkali agent, 0.2 mM of peroxymonosulfate, and 50 mg / L of CuS; the concentration of sulfamethoxazole in the water to be treated in each system is 5 mg / L.

[0072] Figure 1 This is the scanning electron microscope image of the copper oxide and copper sulfide products used in the examples of the present invention. From the image, CuO and CuS are in the form of irregular micro-nano particles.

[0073] Figure 2 This is the X-ray diffraction pattern of the copper oxide and copper sulfide products used in the examples of the present invention. The characteristic diffraction peaks of the CuO and CuS products correspond to the standard CuO (PDF 45-0937) and CuS (PDF 06-0464), and the diffraction peaks are clear and strong.

[0074] The concentrations of sulfamethoxazole at each stage of each system measured by high performance liquid chromatography were used to obtain the degradation effect diagram of sulfamethoxazole, as Figure 3 . (In this application, the original concentration is represented by C0, and the concentration measured after the reaction starts is represented by C t ).

[0075] The EPR spectra of ·OH and SO4 •− captured by DMPO (5,5-dimethyl-dimethyl-1-pyrroline-N-oxide) in the above systems are as Figure 4 shown.

[0076] The change in pH of different systems during the reaction is as Figure 5 shown.

[0077] It can be Figure 3 seen that peroxymonosulfate, the alkali agent, and the copper-based material itself cannot degrade sulfamethoxazole. Not only is the activation effect of the alkali agent and the copper-based material on peroxymonosulfate alone minimal, but the copper-based material after alkali treatment also does not show a significant adsorption effect on sulfamethoxazole. Only when the alkali agent, the copper-based material, and peroxymonosulfate coexist can 100% degradation of sulfamethoxazole be achieved; when using CuO as the copper-based material, sulfamethoxazole degrades rapidly within 15 minutes, and when using CuS, sulfamethoxazole is basically decomposed within 1 minute.

[0078] It can be Figure 4It can be seen that by in-situ alkali-enhanced copper-based materials to activate the peroxymonosulfate system (OH - / CuO / PMS system, OH - / CuS / PMS system), reactive species ·OH and SO4 •− are generated, and the spectral signal intensity captured by EPR is much higher than that of the PMS, OH- / PMS, and copper-based material / PMS systems. Analysis shows that in the presence of an alkali agent, a large number of renewable active sites, such as oxygen vacancies, surface hydroxyl groups, and low-valent copper ions, can be in-situ etched from the copper-based materials, promoting the continuous decomposition of peroxymonosulfate to generate more free radicals. Under the continuous attack of free radicals, sulfamethoxazole is effectively degraded into small molecule non-toxic substances.

[0079] As Figure 5 can be seen, by monitoring the pH change during the reaction process, the introduction of alkali effectively alleviates the problem of excessive acidity of the effluent from the peroxymonosulfate system, and the effluent pH is stably controlled within the compliance range of 6-9 (GB 18918-2002).

[0080] Example 2:

[0081] In the OH - / CuO / PMS system, the effects of alkali agents and peroxymonosulfate with different molar concentration ratios on the degradation of sulfamethoxazole in water.

[0082] To five aqueous solutions containing sulfamethoxazole, sodium hydroxide, copper oxide, and potassium peroxymonosulfate were added simultaneously, and then they were respectively placed in a mechanical stirrer at room temperature for reaction. Among them, the molar concentration ratios of sodium hydroxide to potassium peroxymonosulfate in the five portions were 0.5:1, 1:1, 1.5:1, 2:1, and 2.5:1, respectively, and the dosage of potassium peroxymonosulfate was the same, with a molar concentration of 0.4 mM, and the dosage of CuO was the same at 100 mg / L. The concentration of sulfamethoxazole was 5 mg / L.

[0083] The concentrations of sulfamethoxazole at each stage of each system measured by high performance liquid chromatography respectively, and the effect curves of alkali agents and peroxymonosulfate with different molar concentration ratios on removing sulfamethoxazole are as Figure 6 shown in a. When the reaction time was 20 minutes, when OH - :PMS was 0.5:1, the degradation rate of sulfamethoxazole was 46.1%; when OH - :PMS was 1:1, the degradation rate of sulfamethoxazole was 88.9%; when OH - :PMS was 1.5:1, the degradation rate of sulfamethoxazole was 100%; when OH - :PMS was 2:1, the degradation rate of sulfamethoxazole was 100%; when OH -: When the ratio of OH to PMS is 0.5:1, the degradation rate of sulfamethoxazole is 79.2%. It can be seen that as the ratio of OH - and PMS increases, the degradation rate of sulfamethoxazole first increases and then decreases. When the ratio of OH - and PMS is too high or too low, it is not conducive to the degradation and removal of sulfamethoxazole.

[0084] In the OH - / CuO / PMS system, the effect of different dosages of copper oxide on the degradation of sulfamethoxazole in water.

[0085] To five aqueous solutions containing sulfamethoxazole, sodium hydroxide, copper oxide and potassium peroxymonosulfate were added simultaneously, and then the mixtures were placed in a mechanical stirrer at room temperature for reaction. Among them, the dosages of copper oxide in the five portions were 25, 50, 100, 150 and 200 mg / L respectively, and the molar concentration ratio of sodium hydroxide to potassium peroxymonosulfate was the same, 1.5:1, and the dosage of potassium peroxymonosulfate was the same, with a molar concentration of 0.4 mM. The concentration of sulfamethoxazole was 5 mg / L.

[0086] The concentrations of sulfamethoxazole at each stage of each system were measured by high performance liquid chromatography respectively. The curve of the effect of different dosages of copper oxide on the removal of sulfamethoxazole is as shown in Figure 6 Figure b. After reacting for 20 minutes, when the dosage of CuO was 25 mg / L, the degradation rate of sulfamethoxazole was 53.2%; when the dosage of CuO was 50 mg / L, the degradation rate of sulfamethoxazole was 90.9%; when the dosage of CuO was 100 mg / L, the degradation rate of sulfamethoxazole was 100%; when the dosage of CuO was 150 mg / L, the degradation rate of sulfamethoxazole was 100%; when the dosage of CuO was 200 mg / L, the degradation rate of sulfamethoxazole was 100%. It can be seen that as the dosage of CuO increases, the degradation rate of sulfamethoxazole gradually increases. Considering the economic cost comprehensively, the appropriate dosage of CuO is 100 mg / L.

[0087] Under the action of the alkali agent, a large number of hydroxyl groups are formed on the surface of copper oxide, which can induce the in-situ generation of abundant oxygen vacancies. Specifically, on the one hand, the coexistence of surface hydroxyl groups and oxygen vacancies produces a synergistic effect, which can significantly promote the adsorption and decomposition of peroxymonosulfate; on the other hand, the in-situ alkali etching to generate oxygen vacancies and surface hydroxyl groups is a process of active site regeneration, effectively solving the problem of copper oxide deactivation and endowing the alkali-strengthened copper oxide-activated peroxymonosulfate (OH - / CuO / PMS) system with continuous degradation ability.

[0088] Example 3:

[0089] In the OH -In the / CuS / PMS system, the effects of alkalis and peroxymonosulfate with different molar concentration ratios on the degradation of sulfamethoxazole in water.

[0090] To five aqueous solutions containing sulfamethoxazole, sodium hydroxide, copper sulfide, and potassium hydrogen persulfate were added simultaneously, and then they were respectively placed in a mechanical stirrer at room temperature for reaction. Among them, the molar concentration ratios of sodium hydroxide to potassium hydrogen persulfate in the five solutions were 0.5∶1, 1∶1, 1.5∶1, 2∶1, and 2.5∶1 respectively, and the dosage of potassium hydrogen persulfate was the same, with a molar concentration of 0.2 mM, and the dosage of CuS was the same at 50 mg / L. The concentration of sulfamethoxazole was 5 mg / L.

[0091] The curve graph of the removal effect of sulfamethoxazole by alkalis and peroxymonosulfate with different molar concentration ratios is as Figure 7 shown in a. After reacting for 5 minutes, when OH - ∶PMS was 0.5∶1, the degradation rate of sulfamethoxazole was 34.3%; when OH - ∶PMS increased to more than 1∶1, the degradation rate of sulfamethoxazole was 100%. Considering that the pH of the effluent is preferably maintained between 6 and 9, too high or too low ratios of OH - and PMS are not beneficial, and a ratio of 1.5∶1 is appropriate.

[0092] In the OH - / CuS / PMS system, the effects of different dosages of copper sulfide on the degradation of sulfamethoxazole in water.

[0093] To five aqueous solutions containing sulfamethoxazole, sodium hydroxide, copper sulfide, and potassium hydrogen persulfate with a mass fraction of 42% were added simultaneously, and then they were respectively placed in a mechanical stirrer at room temperature for reaction. Among them, the dosages of copper sulfide in the five solutions were 15, 25, 50, 75, and 100 mg / L respectively, and the molar concentration ratio of sodium hydroxide to potassium hydrogen persulfate was the same, at 1.5∶1, and the dosage of potassium hydrogen persulfate was the same, with a molar concentration of 0.2 mM. The concentration of sulfamethoxazole was 5 mg / L.

[0094] The curve graph of the removal effect of different dosages of copper oxide on sulfamethoxazole is as Figure 7 shown in b. When the dosage of CuS was only 15 mg / L, the complete degradation of sulfamethoxazole could be achieved, but as the dosage of CuS increased, the degradation rate of sulfamethoxazole first increased and then decreased. When the dosage of CuS was 15 mg / L, the degradation rate constant of sulfamethoxazole was 5.53 × 10 -2 s -1 ; when the dosage of CuS was 25 mg / L, the degradation rate constant of sulfamethoxazole was 6.64 × 10 -2 s -1; When the dosage of CuS is 50 mg / L, the degradation rate constant of sulfamethoxazole is 6.88 × 10 -2 s -1 ; When the dosage of CuS is 75 mg / L, the degradation rate constant of sulfamethoxazole is 5.53 × 10 -2 s -1 ; When the dosage of CuS is 100 mg / L, the degradation rate constant of sulfamethoxazole is 5.48 × 10 -2 s -1 。 It can be seen that too high or too low dosage of CuS is not beneficial, and 50 mg / L is appropriate.

[0095] In this example of the method strengthened by copper sulfide, under the action of the alkali agent, the unique S-S bond on the surface of copper sulfide is reduced and broken. With the addition of peroxymonosulfate, the S-S bond is oxidized and restored. The above process accelerates the electron transfer and circulation rate of the reaction process, effectively promotes the regeneration of low-valent copper, realizes the efficient decomposition of peroxymonosulfate, and endows the alkali-strengthened copper sulfide with the ability to activate the continuous degradation of the peroxymonosulfate (OH - / CuS / PMS) system.

[0096] Example 4:

[0097] OH - / CuO / PMS system and OH - / CuS / PMS system for the degradation effects of various refractory new pollutants including ibuprofen (IBP), atrazine (ATZ), quinoline (QNL) and carbamazepine (CBZ).

[0098] Sodium hydroxide, copper-based material and potassium peroxymonosulfate were simultaneously added to the aqueous solutions containing ibuprofen, atrazine, quinoline or carbamazepine respectively, and then they were respectively placed in a mechanical stirrer at room temperature for reaction. Among them, the molar concentration ratio of sodium hydroxide and potassium peroxymonosulfate is the same, which is 1.5∶1. In the OH - / CuO / PMS system, the molar concentration of potassium peroxymonosulfate is the same at 0.4 mM, and the dosage of CuO is the same at 100 mg / L. In the OH - / CuS / PMS system, the molar concentration of potassium peroxymonosulfate is the same at 0.2 mM, and the dosage of CuS is the same at 50 mg / L. The concentrations of the above pollutants are the same, which is 5 mg / L.

[0099] The concentrations of pollutants at each stage of each system measured by high performance liquid chromatography respectively, Figure 8 For the OH - / CuO / PMS system and OH -Degradation effect schematic diagrams of ibuprofen (IBP), atrazine (ATZ), quinoline (QNL) and carbamazepine (CBZ) by the OH - / CuO / PMS system and OH - / CuS / PMS system have excellent degradation effects on ibuprofen, atrazine, quinoline and carbamazepine.

[0100] Example 5:

[0101] The difference between this example and Example 4 is that one or more combinations of potassium hydrogen persulfate, sodium hydrogen persulfate, and calcium monopersulfate are used as peroxymonosulfate. For example, a mixture containing sodium hydrogen persulfate and calcium monopersulfate is used as peroxymonosulfate. Sodium hydroxide and / or potassium hydroxide are used as the base agent. For example, a mixed solution containing sodium hydroxide and potassium hydroxide is added as the base agent. When the above materials are combined materials, the addition amount is calculated based on the sum of the molar concentrations of the composition. For example, the molar concentration ratio of hydroxide ions to hydrogen sulfate ions is the same, which is 1.5:1. The amount of substance of sodium hydroxide and potassium hydroxide can be flexibly adjusted. Copper oxide and copper sulfide are used as the copper-based materials. For example, a mixture with a molar ratio of copper oxide to copper sulfide of 1:1 is used as the copper-based material.

[0102] Using the above systems as reactants can also achieve excellent degradation effects on sulfamethoxazole, ibuprofen, atrazine, quinoline and carbamazepine.

[0103] Example 6:

[0104] Figure 9 It is a schematic diagram of a water treatment device for activating peroxymonosulfate with an alkali-strengthened copper-based material in this example. As Figure 9 shown in a, the device includes: a reactor for accommodating the base agent, peroxymonosulfate, copper-based material and water to be treated, and for carrying out reactions; a base agent adding device connected to the reactor for adding the base agent to the reactor; a peroxymonosulfate adding device connected to the reactor for adding peroxymonosulfate to the reactor; a copper-based material adding device connected to the reactor for adding the copper-based material to the reactor; a water to be treated adding device connected to the reactor for adding the water to be treated to the reactor. When the device is in use, the base agent, copper-based material, peroxymonosulfate and water to be treated are jointly injected into the reactor for reaction.

[0105] As Figure 9 shown in b, in this example, the copper-based material adding device and the reactor are integrated, and the copper-based material is pre-placed in the reactor. When in use, the base agent, peroxymonosulfate and water to be treated are continuously added to the reactor with the copper-based material pre-placed in it, realizing the continuous treatment effect of the device on the water to be treated.

[0106] For Examples 7 and 8 below, the secondary effluent used is the effluent from the secondary sedimentation tank before advanced treatment in a certain urban sewage treatment plant in Beijing. The total nitrogen content in the secondary effluent is 1.46 mg / L, the total phosphorus content is 0.42 mg / L, the COD content is 17 mg / L, the TOC content is 3.89 mg / L, and the pH value is 7.67. Among them, 18 new pollutants mainly composed of sulfonamides are detected, and the maximum concentration can reach 53.56 ng / L.

[0107] Figure 10 a is the schematic diagram of the continuous flow device for sulfamethoxazole under the background of the long-term treatment of the secondary effluent of the sewage treatment plant based on the OH - / CuO / PMS system. Figure 10 b is the schematic diagram of the continuous flow device for sulfamethoxazole under the background of the long-term treatment of the secondary effluent of the sewage treatment plant based on the OH - / CuS / PMS system.

[0108] Example 7:

[0109] Effect of the long-term treatment of sulfamethoxazole in the secondary effluent of the sewage treatment plant based on the OH - / CuO / PMS system.

[0110] The construction, operation method and process of the continuous flow device are specifically as follows: A cylindrical plexiglass tube with a diameter of 2 cm, a height of 6.8 cm and a volume of about 21 mL is filled with absorbent cotton. An aqueous solution dispersing 400 mg of copper oxide is dropped between the cotton columns to make a reaction column. Then, the secondary effluent (0.25 mL / min) containing sodium hydroxide and sulfamethoxazole and the potassium peroxymonosulfate solution with a mass fraction of 42% (0.25 mL / min) are simultaneously introduced into the above reaction column at a flow rate of 0.5 mL / min, and the hydraulic retention time in the reaction column is about 42 min. Among them, the molar concentration ratio of sodium hydroxide to potassium peroxymonosulfate is 1.5:1, and the dosage of potassium peroxymonosulfate is 0.5 mM. The concentration of sulfamethoxazole is 5 mg / L.

[0111] Figure 11 It shows that the continuous flow device can operate stably for at least 12 days. During this period, the removal rate of sulfamethoxazole in the secondary effluent is continuously higher than 95% ( Figure 11 a), and the average mineralization rate reaches 64.34% ( Figure 11 b); the utilization rate of PMS is maintained above 84% ( Figure 11 c), the average leaching concentration of copper ions is stably controlled below 0.1 mg / L, and the pH value of the effluent is stabilized at about 7 ( Figure 11d). The above results fully demonstrate that the copper oxide-activated persulfate technology based on alkaline in-situ strengthening is environmentally friendly. The excellent performance of this system not only stems from the complete degradation of pollutants, but also benefits from its high PMS utilization rate and the characteristic of trace Cu ion residue.

[0112] The copper-based material in this example can be separated after use and reused together with alkali agent and persulfate again, which has the technical advantages of easy recovery and reuse.

[0113] Example 8:

[0114] Based on OH - / CuS / PMS system for the long-term treatment of sulfamethoxazole in the secondary effluent of a sewage treatment plant.

[0115] The construction, operation method and process of the continuous flow device are specifically as follows: A cylindrical plexiglass tube with a diameter of 2 cm, a height of 6.8 cm and a volume of about 21 mL is filled with absorbent cotton. An aqueous solution dispersing 200 mg of copper sulfide is dropped between the cotton layers to make a reaction column. Then, the secondary effluent (0.25 mL / min) containing sodium hydroxide and sulfamethoxazole and the potassium peroxymonosulfate solution with a mass fraction of 42% (0.25 mL / min) are simultaneously introduced into the above reaction column at a flow rate of 0.5 mL / min, and the hydraulic retention time in the reaction column is about 42 min. Among them, the molar concentration ratio of sodium hydroxide to potassium peroxymonosulfate is 1.5:1, and the dosage of potassium peroxymonosulfate is 0.5 mM. The concentration of sulfamethoxazole is 5 mg / L.

[0116] Figure 12 It shows that the continuous flow device can operate stably for at least 12 days, during which the removal rate of sulfamethoxazole in the secondary effluent is continuously higher than 95% ( Figure 12 a), and the average mineralization rate reaches 70.56% ( Figure 12 b); the PMS utilization rate is maintained above 91% ( Figure 12 c), the average leaching concentration of copper ions is stably controlled below 0.1 mg / L, and the effluent pH value is stable at about 7 ( Figure 12 d). The above results fully demonstrate that the copper sulfide-activated persulfate technology based on alkaline in-situ strengthening is environmentally friendly. The excellent performance of this system not only stems from the complete degradation of pollutants, but also benefits from its high PMS utilization rate and the characteristic of trace Cu ion residue.

[0117] The alkali-strengthened copper-based material excitation persulfate water treatment method and device in the embodiments of the present invention are used to solve the technical problems such as excessive dosage of oxidant and catalyst, poor effect, low oxidant utilization rate, metal ion dissolution and over-acidic effluent in the traditional transition metal-activated persulfate system.

[0118] In the specific embodiments described above, the object, technical solution and beneficial effects of the present invention have been further described in detail. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for treating copper-based materials with alkali-enhanced peroxymonosulfate solution, characterized in that: The method comprises: adding an alkali agent, a copper-based material, and peroxymonosulfate into water to be treated; The alkaline agent is sodium hydroxide and / or potassium hydroxide; The copper-based material is copper oxide and / or copper sulfide; The peroxymonosulfate is one or a combination of two or more of potassium persulfate, sodium persulfate, and calcium monopersulfate.

2. The method according to claim 1, characterized in that The alkali agent and peroxymonosulfate are added in the form of a solution, wherein the molar concentration ratio of hydroxide ion to peroxymonosulfate is 0.5-2.5:

1.

3. The method according to claim 1, characterized in that The alkali agent and peroxymonosulfate are added in the form of a solution, wherein the molar concentration ratio of hydroxide ion to peroxymonosulfate is 1-2:

1.

4. The method according to claim 1, characterized in that: The peroxymonosulfate is potassium hydrogen persulfate.

5. The method according to claim 1, characterized in that The copper-based material is copper oxide, and the copper oxide dosage is 25-200 mg / L.

6. The method according to claim 1, characterized in that The copper-based material is copper oxide, and the copper oxide dosage is 50-150 mg / L.

7. The method according to claim 1, characterized in that The copper-based material is copper sulfide, and the copper sulfide dosage is 15-100 mg / L.

8. The method according to claim 1, characterized in that The copper-based material is copper sulfide, and the copper sulfide dosage is 25-75 mg / L.

9. The method according to claim 1, characterized in that: The water to be treated contains free radical degradable pollutants.

10. An alkali-enhanced copper-based material-activated peroxymonosulfate water treatment device, characterized in that: The device comprises: A reactor for containing an alkali agent, peroxymonosulfate, a copper-based material and water to be treated, and for carrying out a reaction; an alkali agent adding device, connected to the reactor, and used for adding the alkali agent into the reactor; a peroxymonosulfate adding device, connected to the reactor, for adding peroxymonosulfate into the reactor; A copper-based material adding device, connected to the reactor, for adding the copper-based material to the reactor; The device for adding water to be treated is connected to the reactor and is used for adding water to be treated into the reactor.

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