Potassium-based ozone oxidation catalyst with ternary active sites

Abstract

The invention relates to a potassium-based ozone oxidation catalyst with ternary active sites, the potassium-based ozone oxidation catalyst is composed of a carrier and ternary active components loaded on the carrier, and the ternary active components are K, N-C and S-C. Compared with a traditional transition metal oxide catalyst, the catalyst has the advantages of being high in catalytic efficiency and stability, easy and convenient to prepare and the like, and the problem of secondary pollution caused by transition metal ion leaching does not exist. When the catalyst is used for treating reverse osmosis concentrated water of a petrochemical industry factory, the fluorescence intensity of each region of a three-dimensional fluorescence spectrum of oxidized effluent is greatly reduced, tryptophan-like (region II), fulvic acid-like (region III) and humic acid-like (region V) are completely degraded, the COD removal rate can be stably greater than or equal to 40% in the aspect of COD removal, and the COD removal efficiency is greatly improved. Therefore, the catalyst has a good treatment effect on the reverse osmosis concentrated water of petrochemical industry factories.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wastewater treatment, and relates to an ozone oxidation catalyst with ternary active sites for advanced treatment of salt-containing organic wastewater as well as a preparation method and application thereof. BACKGROUND

[0002] Salt-containing organic wastewater is mainly produced in typical high-water-consuming industries such as petroleum chemical industry and textile printing and dyeing, and has the characteristics of high salt concentration, great biological toxicity and poor biodegradability, and belongs to industrial wastewater difficult to biodegrade, which contains carcinogenic, teratogenic and mutagenic effect substances, and seriously threatens the ecological environment of water bodies and human health. Developing efficient advanced treatment technology for such wastewater has become a research hotspot in the field of environmental engineering.

[0003] As a kind of efficient and synergistic treatment technology, heterogeneous catalytic ozone oxidation process has shown significant advantages in the treatment of high-salt organic wastewater. Through the surface active components of heterogeneous catalysts, ozone is decomposed to generate hydroxyl radicals (·OH), superoxide radicals (·O2 - ) and other highly active oxidizing species, and the efficient mineralization of organic pollutants is realized through the chain oxidation reaction mediated by free radicals. Compared with homogeneous catalytic systems, this technology can realize the rapid separation and recovery of catalytic components from the reaction system through the design of catalyst structure by immobilization, which fundamentally avoids the secondary pollution risk caused by the leaching of metal ions, and has significant potential for industrial application. The specific mechanism is as follows: ozone molecules are chemically adsorbed on the metal active sites on the surface of the catalyst, and are dissociated to generate active oxygen species through an electron transfer process; at the same time, organic pollutants in wastewater are enriched in the mesoporous structure of the catalyst through chemical bonding or physical adsorption, and non-heterogeneous oxidation reaction occurs between the active oxygen species and the organic pollutants in the interface microzone, finally completing the deep destruction and decomposition of the molecular structure of the organic pollutants. The core of the technology lies in the development of a multifunctional catalyst system with high catalytic activity and excellent stability.

[0004] Domestic and foreign scholars have made series of progress in the research on catalyst active component screening, carrier modification strategy and structure-activity relationship, but the traditional materials still have the technical bottlenecks of insufficient dispersion of active sites, limited mass transfer efficiency and weak resistance to salt ion interference, which leads to the catalytic performance decay of the reaction system in a high-salt environment, which has become a key problem restricting the scale application of the technology. The most commonly used heterogeneous catalysts at present are mainly transition metal oxide catalysts, including single-metal or multi-metal oxide catalysts containing Fe, Mn, Ce, Zn and Ti, etc. Due to the collision of catalyst particles in the ozone catalytic oxidation process, the metal active components on the surface of the transition metal oxide catalysts are easy to leach, causing secondary pollution.

[0005] The above problems are particularly prominent for petrochemical industrial plant wastewater, for example, reverse osmosis concentrated water of petrochemical industrial plants usually contains pollutants such as benzene, toluene, xylene (BTEX), polycyclic aromatic hydrocarbons (PAHs), phenols, sulfides, ammonia nitrogen, heavy metals (such as mercury, lead, chromium), and high-concentration salts (such as Cl - , SO4 2- ) and the like. After reverse osmosis treatment, there are still residual non-biodegradable organic matter (such as long-chain alkanes, part of heterocyclic compounds and polycyclic aromatic hydrocarbons), inorganic salts, trace heavy metals and nitrogen and phosphorus nutrients in the wastewater; among them, polycyclic aromatic hydrocarbons are difficult to be completely degraded by microorganisms due to high hydrophobicity and stable structure, and the presence of high salt and heavy metals will inhibit microbial activity, resulting in reduced efficiency of subsequent biochemical treatment. For a long time, although domestic and foreign scholars have carried out a large number of researches on catalyst active component selection, carrier modification strategy and structure-activity relationship in order to solve the problem of reverse osmosis concentrated water treatment of petrochemical industrial plants, but the effect is very small, therefore, it has become a technical problem that the technical personnel in the field have been trying to solve for a long time but have been unable to solve to realize efficient treatment of reverse osmosis concentrated water of petrochemical industrial plants through catalyst technology. SUMMARY

[0006] One of the purposes of the present application is to provide a potassium-based ozone oxidation catalyst with ternary active sites in view of the problems existing in the prior art; compared with traditional metal oxide catalysts, the active sites of the catalyst are green metal-nonmetal dual active sites (K, N-C and S-C), there is no potential risk of heavy metal pollution caused by metal ion leaching of traditional transition metal oxide catalysts, and the catalyst can efficiently treat reverse osmosis concentrated water of petrochemical industrial plants.

[0007] The second purpose of the present application is to provide a preparation method of the above-mentioned potassium-based ozone oxidation catalyst with ternary active sites, so as to prepare the above-mentioned potassium-based ozone oxidation catalyst with ternary active sites by the method, the preparation process is simple, the prepared catalyst has high catalytic efficiency and high stability, and can be recycled and reused.

[0008] Therefore, the first aspect of the present application provides a potassium-based ozone oxidation catalyst with ternary active sites, which is composed of a carrier and dual active components loaded on the carrier, wherein the ternary active components are K, N-C and S-C respectively.

[0009] According to the present application, the carrier is modified on the surface; preferably, the surface modification is to coat polymer on the surface of the carrier based on a modifier, and to simultaneously construct K, N-C and S-C ternary active sites with potassium hydroxide as a crosslinking agent and K site precursor, and thiourea as an S-C site precursor; further preferably, the modifier is dopamine hydrochloride.

[0010] In some embodiments of the present application, the specific surface area of the ozone oxidation catalyst is 110-150 m 2 / g, and the pore volume is 0.4-0.6 cm 3 / g.

[0011] The second aspect of the present application provides a preparation method of a potassium-based ozone oxidation catalyst with ternary active sites, comprising:

[0012] Step A: washing the carrier with water, drying, calcining, and obtaining a pretreated carrier;

[0013] Step B: placing the pretreated carrier in a potassium hydroxide aqueous solution, adding a modifier and thiourea, stirring, then filtering, washing, and drying to obtain a dry catalyst precursor;

[0014] Step C: calcining the dry catalyst precursor to obtain a potassium-based ozone oxidation catalyst with ternary active sites.

[0015] According to the present application, in Step A, the drying is performed under vacuum conditions, the drying temperature is 60-120℃, and the drying time is 6-12h.

[0016] In some embodiments of the present application, in Step A, the calcination temperature is 200-350℃, and the calcination time is 2-5h.

[0017] In some embodiments of the present application, in Step B, the modifier is dopamine hydrochloride, and the mass ratio of the modifier to the pretreated carrier is 1:30.

[0018] In some embodiments of the present application, in Step B, the concentration of potassium hydroxide is 0.5g / L-1g / L, and the mass ratio of the sodium metasilicate to the pretreated carrier is 1:200-400.

[0019] In some embodiments of the present application, in Step B, the amount of thiourea added is 0.75-2.25g / L based on the volume of the potassium hydroxide aqueous solution.

[0020] In some embodiments of the present application, in Step B, the stirring temperature is 20-35℃, and the stirring time is 6-12h.

[0021] In some embodiments of the present application, in Step B, the drying is performed under vacuum conditions, the drying temperature is 60-80℃, and the drying time is 6-12h.

[0022] In some embodiments of the present application, in Step C, the calcination is performed under an inert gas atmosphere, the calcination temperature is 700-900℃, and / or the calcination time is 2-5h.

[0023] The third aspect of the present application provides an application of the ozone oxidation catalyst according to the first aspect of the present application or the ozone oxidation catalyst prepared by the preparation method according to the second aspect of the present application in deep treatment of salt-containing organic wastewater.

[0024] The application comprises loading the ozone oxidation catalyst in a wastewater treatment device, passing the wastewater, and passing ozone to perform ozone oxidation treatment on the wastewater, so as to obtain oxidized effluent water meeting the discharge standard.

[0025] In the present application, the salt-containing organic wastewater comprises petrochemical wastewater reverse osmosis concentrated water and / or chemical wastewater; the COD of the wastewater is 40-60 mg / L, and the TDS is 3180-3190 mg / L.

[0026] In some embodiments of the present application, the reaction conditions of the ozone oxidation treatment are as follows: the pH of the wastewater is 8.13, the ozone flow rate is 0.03 L / min, the catalyst loading amount is 200 g / L, the reaction time is 60 min, and the ozone addition ratio is 0.8-2.2.

[0027] The present application provides a potassium-based ozone oxidation catalyst with ternary active sites prepared based on carrier surface coating. Compared with traditional transition metal oxide catalysts, the catalyst has the advantages of high catalytic efficiency, high stability, simple preparation, etc., and does not have the problem of secondary pollution caused by leaching of transition metal ions. In addition, the porous material used as the catalyst carrier has a high specific surface area and a large pore volume, and has good adsorption capacity. The catalyst can significantly assist the catalytic oxidation reaction by enriching pollutants on the catalyst surface. When the catalyst is used to treat reverse osmosis concentrated water of a petrochemical industry factory, the fluorescence intensity of each region of the three-dimensional fluorescence spectrum of the oxidized effluent water is significantly reduced, among which the tryptophan-like (region II), fulvic acid-like (region III), and humic acid-like (region V) are completely degraded. In terms of COD removal, a COD removal rate of ≥40% can be stably achieved, which indicates that the catalyst has good treatment effect on the reverse osmosis concentrated water of the petrochemical industry factory. BRIEF DESCRIPTION OF DRAWINGS

[0028] The present application will be further described below with reference to the accompanying drawings.

[0029] Figure 1 The preparation process of the potassium-based ozone oxidation catalyst with ternary active sites in the present application is shown, wherein a is a pretreated alumina carrier, b is a catalyst precursor coated with dopamine, and c is a catalyst formed by calcining the catalyst precursor.

[0030] Figure 2 The three-dimensional fluorescence spectrum of the salt-containing organic wastewater (reverse osmosis concentrated water of a certain petrochemical industry factory) in the present application is shown.

[0031] Figure 3 The three-dimensional fluorescence spectrum of the effluent treated by ozone oxidation in Example 5.

[0032] Figure 4 The three-dimensional fluorescence spectrum of the effluent treated by ozone oxidation in Comparative Example 1. DETAILED DESCRIPTION

[0033] In order to make the present application easily understood, the present application will be described in detail below in conjunction with examples. However, before the present application is described in detail, it should be understood that the present application is not limited to the particular implementation described. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0034] Unless otherwise defined, all terms used in connection with the present application, have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are now described.

[0035] I. Terminology

[0036] The term "TDS" (Total dissolved solids) in the present application, also known as total dissolved solids, measured in milligrams per liter (mg / L), indicates how many milligrams of dissolved solids are dissolved in 1 liter of water. The higher the TDS value, the more dissolved substances contained in the water. Total dissolved solids refer to the total amount of all solutes in water, including the content of inorganic and organic substances. Generally, the conductivity value can be used to roughly understand the salt content in the solution. Generally, the higher the conductivity, the higher the salt content, and the higher the TDS. Therefore, TDS also reflects the salt level in wastewater.

[0037] The term "wastewater advanced treatment" in the present application generally refers to further treatment of residual organic matter in concentrated water after reverse osmosis by using advanced oxidation technology and the like.

[0038] The term "water" in the present application, without special explanation, refers to deionized water, distilled water or ultrapure water.

[0039] II. Embodiments

[0040] As described previously, although scholars at home and abroad have made a series of progress in the selection of active components of catalysts, modification strategies of carriers and structure-activity relationship research, but the traditional catalytic materials still have technical bottlenecks such as insufficient dispersion of active sites, limited mass transfer efficiency and weak resistance to salt ion interference, which leads to the catalytic performance decay in the high salt environment; and the most commonly used heterogeneous catalysts cause secondary pollution due to the leaching of metal active components on the surface of transition metal oxide catalysts caused by the collision of catalyst particles in the process of ozone catalytic oxidation. These problems are particularly prominent for the wastewater of petrochemical industry factory. In addition to the above problems, it is also difficult to achieve efficient treatment of reverse osmosis concentrated water of petrochemical industry factory by using traditional catalytic materials or the most commonly used heterogeneous catalysts. It has become a technical problem that the technical personnel in the field have been trying to solve for a long time but have been unable to solve. Therefore, the inventors have conducted a lot of in-depth research on ozone oxidation catalysts and treatment technology of reverse osmosis concentrated water of petrochemical industry factory.

[0041] The inventors have found that a potassium-based novel efficient ozone oxidation catalyst with ternary active sites can be prepared by using alumina as a carrier, using a potassium hydroxide solution as a crosslinking agent and K-site precursor, using thiourea as an S-C site precursor, and simultaneously performing surface modification and site attachment based on the monomer of dopamine hydrochloride salt modifier on the surface of the carrier, which is also an N-C site precursor. The catalyst can efficiently treat the reverse osmosis concentrated water of petrochemical industry factory, and the catalyst is simple to synthesize, has good catalytic performance, high stability and can be recycled.

[0042] To achieve the present application, the present application provides a preparation method of a potassium-based ozone oxidation catalyst with ternary active sites, and the preparation process is as follows Figure 1 The preparation method comprises the following steps:

[0043] (1) carrier pretreatment based on water washing, drying and calcination process:

[0044] The catalyst carrier is placed in a beaker, washed with deionized water for 1-3 times to remove surface impurities, dried in a vacuum drying oven at 60-120 DEG C, preferably 105 DEG C for 6-12 h, and then placed in a muffle furnace at 200-350 DEG C, preferably 350 DEG C for 2-5 h to realize the removal of organic impurities and the unblocking of the carrier pores, and obtain the pretreated carrier.

[0045] (2) carrier surface modification based on the polymerization process of dopamine in alkaline solution (the polymer chain formed has amino and hydroxyl groups, etc.):

[0046] A potassium hydroxide aqueous solution with a concentration of 0.5-1 g / L is prepared and added into a conical flask, then the pretreated carrier is added, and then dopamine hydrochloride (a modifier) and thiourea are added, and the mixture is stirred at 20-35°C for 2-12 h, filtered, washed with water and ethanol, and dried in a vacuum drying oven at 40-80°C for 6-12 h to obtain a dry catalyst precursor.

[0047] As a further improvement of the present application, the use of a carrier surface coating step is proposed in the catalyst preparation process to construct K (potassium), N-C (nitrogen-carbon) and S-C (sulfur-carbon) ternary active sites, and potassium hydroxide solution is used as a modifier and K precursor, which not only achieves the purpose of surface coating, but also loads active sites.

[0048] Preferably, in this step, the mass ratio of the modifier (dopamine hydrochloride) to the pretreated carrier is 1:30.

[0049] In some examples, the concentration of the potassium hydroxide aqueous solution is 0.5-1 g / L, and the mass ratio of the potassium hydroxide to the pretreated carrier is 1:200-400.

[0050] In some examples, the amount of thiourea added is 0.75-2.25 g / L

[0051] (3) The dry catalyst precursor is calcined at 600-1000°C under an inert gas atmosphere for 1-5 h to obtain a potassium-based ozone oxidation catalyst with ternary active sites.

[0052] Based on the above preparation method, a potassium-based ozone oxidation catalyst with double non-metal ternary active sites for deep treatment of salt-containing organic wastewater is prepared, which is composed of a carrier and a double non-metal ternary active component loaded on the carrier, wherein the double non-metal ternary active component is K, N-C and S-C, and the carrier is alumina.

[0053] The potassium-based ozone oxidation catalyst with double non-metal ternary active sites provided herein is a heterogeneous catalyst, and the active sites are K, N-C and S-C. The catalyst has high catalytic efficiency and high stability, and can be recycled and reused.

[0054] According to the present application, the carrier is coated by surface coating; preferably, the surface coating is based on the coating and polymerization of the cross-linking monomer dopamine on the surface of the carrier, with potassium hydroxide serving as a pH adjuster to adjust the pH value of the solution to be alkaline, so that dopamine is cross-linked on the surface of the carrier, and dopamine serves as a K site precursor, dopamine serves as an N-C site precursor, and thiourea is added as an S-C site precursor, and K, N-C and S-C ternary active sites are constructed synchronously; further preferably, the added potassium hydroxide can be used as a cross-linking agent for coating and cross-linking, replacing the traditional Tri-HCl buffer solution, and the catalyst is synthesized in one step.

[0055] The catalyst can be represented as K-NSC@Al2O3.

[0056] In some embodiments of the present application, the specific surface area of the ozone oxidation catalyst is 110-150 m 2 / g, preferably 129.5-145 m 2 / g, the pore volume is 0.4-0.6 cm 3 / g, preferably 0.4-0.55 cm 3 / g.

[0057] The application of the above-mentioned ozone oxidation catalyst in the deep treatment of salt-containing organic wastewater can be understood as a method for deep treatment of wastewater by using the above-mentioned ozone oxidation catalyst.

[0058] Specifically, the application comprises loading the ozone oxidation catalyst in a wastewater treatment device, passing in wastewater, and passing in ozone to perform ozone oxidation treatment on the wastewater, so as to obtain oxidized effluent water meeting the discharge standard.

[0059] The wastewater treatment device in the present application is not particularly limited as long as it can realize ozone catalytic oxidation, for example, a conventional wastewater treatment device for ozone catalytic oxidation in the art can be used.

[0060] The salt-containing organic wastewater in the present application includes but is not limited to wastewater reverse osmosis concentrated water of a petrochemical plant and / or chemical wastewater.

[0061] In some embodiments of the present application, the wastewater is reverse osmosis concentrated water of a petrochemical plant.

[0062] The three-dimensional fluorescence spectrum of the wastewater is as shown in the following figure. Figure 2 The three-dimensional fluorescence spectrum (EEM) is a powerful analysis technology for obtaining complete fluorescence fingerprint information of a sample by simultaneously scanning excitation and emission wavelengths. The three-dimensional fluorescence spectrum analysis of the wastewater can determine the organic matter contained in the water, and the three-dimensional fluorescence spectrum can be divided into five regions. Region I: tyrosine-like substances, excitation / emission wavelength (Eex / Eem) is 200-250 nm / 200-330 nm; Region II: tryptophan-like substances, Eex / Eem is 200-250 nm / 330-380 nm; Region III: fulvic acid-like substances, Eex / Eem is 200-250 nm / 380-500 nm; Region IV: soluble metabolic product-like organic matter (SMP), Eex / Eem is 250-350 nm / 200-380 nm; Region V: humic acid-like substances, Eex / Eem is 250-400 nm / 380-500 nm. The composition of organic matter in raw water is complex, mainly composed of tryptophan-like substances (region II) and fulvic acid-like substances (region III).

[0063] COD of the wastewater: 40-60 mg / L, TDS: 3180-3190 mg / L.

[0064] The reaction condition of the ozone oxidation treatment is that the pH of the wastewater is 8.13, the ozone flow is 0.03 L / min, the catalyst loading is 200 g / L, the reaction time is 60 min, and the ozone addition ratio is 0.8-2.2.

[0065] The experimental results show that the COD removal rate of the wastewater treated by the ozone oxidation catalyst is greater than or equal to 40%, and even as high as 53.93% when the reverse osmosis concentrated water of a petroleum chemical industry factory is treated.

[0066] The present application improves the preparation method of the catalyst, uses K, N-C and S-C as green and efficient active components, uses dopamine hydrochloride (DA) to coat the carrier, anchors the active components based on the chemical bond effect of the cross-linking process, and enhances the stability of the catalyst, thereby preparing a green and efficient new type of double non-metallic site ozone oxidation catalyst; the present application directly provides a DA cross-linking alkaline environment by using potassium hydroxide, loads the active components on the carrier by using a one-step method, the preparation process is simple and fast, the cost is effectively saved, the catalyst has good catalytic performance for the deep treatment of salt-containing organic wastewater (for example, the reverse osmosis concentrated water of a petroleum chemical industry factory), is suitable for large-scale industrial production, and has a broad prospect.

[0067] III. Examples

[0068] The present application is further specifically described below by means of the drawings and specific examples. The experimental methods described below are all conventional laboratory methods unless otherwise specified. The experimental materials described below can be obtained from commercial channels unless otherwise specified.

[0069] In the following examples, the COD is determined by using a Hash COD reagent on a Hash DRB200 digestion instrument (American Hash Company) after digestion, and then determined by using a DR5000 ultraviolet spectrophotometer (American Hash Company). The TDS is determined by using a DDSJ-319L type conductivity meter (Shanghai Ray Meter Instrument Co., Ltd.). The COD removal rate is calculated according to the following formula:

[0070] COD removal rate = (COD 原始 -COD 氧化后 ) / COD 原始 ×100%.

[0071] Example 1:

[0072] Aluminum oxide (3-5 mm) is used as the carrier to prepare the catalyst and determine the performance.

[0073] (1) The alumina trihydrate was washed in deionized water for 3 times to remove dust, dried in a vacuum drying oven at 120℃ for 10h, and then calcined in a muffle furnace at 350℃ for 4h to remove organic impurities in the pores and on the surface, to obtain a pretreated carrier;

[0074] (2) The pretreated carrier was placed in a 0.8g / L potassium hydroxide solution, the ratio of potassium hydroxide to pretreated carrier was 1:250, 1g of dopamine hydrochloride and 0.1125g of thiourea were added, the mass ratio of dopamine hydrochloride to pretreated carrier was 1:30, and then stirred for 6h, filtered and washed with water and ethanol, and dried in a vacuum drying oven at 60℃ for 6h to obtain a catalyst precursor;

[0075] (3) The catalyst was dried and placed in a tube furnace under an inert gas atmosphere, and calcined at 700℃ for 2h to obtain a K-NSC@Al2O3 catalyst sample.

[0076] The ozone oxidation catalyst was loaded in a wastewater treatment device, wastewater was introduced, and ozone was introduced to perform ozone oxidation treatment on the wastewater:

[0077] The wastewater was reverse osmosis concentrated water from a certain petrochemical industry factory, the COD of the wastewater was 40-60mg / L, and the TDS was 3180-3190mg / L;

[0078] The reaction conditions were as follows: pH=8.13, ozone flow rate was 0.03L / min, catalyst loading amount was 200g / L, reaction time was 60min, and ozone addition ratio was 1.1.

[0079] The experimental results showed that the COD removal rate could reach 42.37%, and the catalyst did not show obvious powder loss during the catalytic process, and had good reusability.

[0080] Example 2:

[0081] Alumina trihydrate (3-5mm) was used as a carrier to prepare a catalyst and determine its performance.

[0082] (1) The alumina trihydrate was washed in deionized water for 3 times to remove dust, dried in a vacuum drying oven at 120℃ for 10h, and then calcined in a muffle furnace at 350℃ for 4h to remove organic impurities in the pores and on the surface, to obtain a pretreated carrier;

[0083] (2) The pretreated carrier is placed in a 0.8 g / L potassium hydroxide solution, the dosage ratio of potassium hydroxide to the pretreated carrier is 1:250, 1 g of dopamine hydrochloride and 0.1125 g of thiourea are added, the mass ratio of dopamine hydrochloride to the pretreated carrier is 1:30, after sufficient stirring for 6 h, filtration and washing with water and ethanol, drying in a vacuum drying oven at 60℃ for 6 h, a catalyst precursor is obtained;

[0084] (3) The catalyst is dried and then placed in a tube furnace under an inert gas atmosphere, calcined at 800℃ for 2 h, and a K-NSC@Al2O3 catalyst sample is obtained.

[0085] The ozone oxidation catalyst is loaded in a wastewater treatment device, wastewater is introduced, and ozone is introduced to perform ozone oxidation treatment on the wastewater:

[0086] The wastewater is reverse osmosis concentrated water of a certain petrochemical industrial factory, the COD of the wastewater is 40-60 mg / L, and the TDS is 3180-3190 mg / L.

[0087] The reaction conditions are as follows: pH = 8.13, ozone flow rate is 0.03 L / min, catalyst loading amount is 200 g / L, reaction time is 60 min, and ozone addition ratio is 2.2.

[0088] The experimental results show that the COD removal rate can reach 53.93%, and the catalyst does not obviously fall off during the catalytic process, and the reusability is good.

[0089] Example 3:

[0090] Aluminum oxide (3-5 mm) is used as a carrier to prepare a catalyst and determine the performance.

[0091] (1) The aluminum oxide is washed in deionized water for 3 times to remove dust, dried in a vacuum drying oven at 120℃ for 10 h, and then calcined in a muffle furnace at 350℃ for 4 h to remove organic impurities in the pores and on the surface, and a pretreated carrier is obtained.

[0092] (2) The pretreated carrier is placed in a 0.8 g / L potassium hydroxide solution, the dosage ratio of potassium hydroxide to the pretreated carrier is 1:250, 1 g of dopamine hydrochloride and 0.3375 g of thiourea are added, the mass ratio of dopamine hydrochloride to the pretreated carrier is 1:30, after sufficient stirring for 6 h, filtration and washing with water and ethanol, drying in a vacuum drying oven at 60℃ for 6 h, a catalyst precursor is obtained.

[0093] (3) The catalyst is dried and then placed in a tube furnace under an inert gas atmosphere, calcined at 800℃ for 3 h, and a K-NSC@Al2O3 catalyst sample is obtained.

[0094] An ozone oxidation catalyst is filled in a wastewater treatment device, wastewater is introduced, and ozone is introduced to perform ozone oxidation treatment on the wastewater:

[0095] The wastewater is reverse osmosis concentrated water of a certain petrochemical industrial factory, the COD of the wastewater is 40-60 mg / L, and the TDS is 3180-3190 mg / L.

[0096] The reaction conditions are that the pH is 8.13, the ozone flow rate is 0.03 L / min, the catalyst filling amount is 200 g / L, the reaction time is 60 min, and the ozone addition ratio is 1.9.

[0097] The experimental results show that the COD removal rate can reach 49.74%, and the catalyst does not obviously fall off during the catalysis process, and the reusability is good.

[0098] Example 4:

[0099] Aluminum oxide (3-5 mm) is used as a carrier to prepare a catalyst and determine the performance.

[0100] (1) The aluminum oxide is washed in deionized water for 3 times to remove dust, dried in a vacuum drying box at 120°C for 10 h, and then calcined in a muffle furnace at 350°C for 4 h to remove organic impurities in the pores and on the surface, to obtain a pretreated carrier;

[0101] (2) The pretreated carrier is placed in a 0.8 g / L potassium hydroxide solution, the amount ratio of potassium hydroxide to the pretreated carrier is 1:250, 1 g of dopamine hydrochloride and 0.1125 g of thiourea are added, the mass ratio of dopamine hydrochloride to the pretreated carrier is 1:30, the mixture is stirred for 12 h, then filtered and washed with water and ethanol, and placed in a vacuum drying box to dry at 60°C for 6 h, to obtain a catalyst precursor;

[0102] (3) The catalyst is dried and placed in a tube furnace under an inert gas atmosphere, and calcined at 800°C for 2 h to obtain a K-NSC@Al2O3 catalyst sample.

[0103] An ozone oxidation catalyst is filled in a wastewater treatment device, wastewater is introduced, and ozone is introduced to perform ozone oxidation treatment on the wastewater:

[0104] The wastewater is reverse osmosis concentrated water of a certain petrochemical industrial factory, the COD of the wastewater is 40-60 mg / L, and the TDS is 3180-3190 mg / L.

[0105] The reaction conditions are that the pH is 8.13, the ozone flow rate is 0.03 L / min, the catalyst filling amount is 200 g / L, the reaction time is 60 min, and the ozone addition ratio is 0.8.

[0106] The experimental results show that the COD removal rate can reach 41.27%, and the catalyst does not obviously fall off during the catalysis process, and the reusability is good.

[0107] Example 5:

[0108] Aluminum oxide (3-5mm) is used as a carrier to prepare the catalyst and determine the performance.

[0109] (1) The aluminum oxide is washed in deionized water for 3 times to remove dust, and then dried in a vacuum drying oven at 120°C for 10h, and then calcined in a muffle furnace at 350°C for 4h to remove organic impurities in the pores and surface, to obtain a pretreated carrier;

[0110] (2) The pretreated carrier is placed in a 0.8g / L potassium hydroxide solution, and the ratio of potassium hydroxide to pretreated carrier is 1:250, 1g dopamine hydrochloride and 0.285g thiourea are added, and the ratio of dopamine hydrochloride to pretreated carrier is 1:20, and then stirred for 6h, filtered and washed with water and ethanol, and then dried in a vacuum drying oven at 60°C for 6h to obtain a catalyst precursor;

[0111] (3) The catalyst is dried and placed in a tube furnace under an inert gas atmosphere, and then calcined at 800°C for 3h to obtain a K-NSC@Al2O3 catalyst sample.

[0112] The detection results show that the specific surface area of the ozone oxidation catalyst prepared in the above examples is 110-150m 2 / g, and the pore volume is 0.4-0.6cm 3 / g.

[0113] The ozone oxidation catalyst is filled in a wastewater treatment device, wastewater is introduced, and ozone is introduced to perform ozone oxidation treatment on the wastewater:

[0114] The wastewater is reverse osmosis concentrated water of a certain petrochemical industry factory, and the COD of the wastewater is 40-60mg / L, and the TDS is 3180-3190mg / L.

[0115] The wastewater is analyzed by three-dimensional fluorescence spectroscopy (Hitachi F7000 fluorescence spectrophotometer, scientific compass test platform detection), and the three-dimensional fluorescence spectrum of the wastewater is as follows Figure 2The organic matter in water can be determined, and the three-dimensional fluorescence spectrum can be divided into five regions. Region I: tyrosine-like substances, excitation / emission wavelength (Eex / Eem) is 200-250 nm / 200-330 nm; Region II: tryptophan-like substances, Eex / Eem is 200-250 nm / 330-380 nm; Region III: fulvic acid-like substances, Eex / Eem is 200-250 nm / 380-500 nm; Region IV: soluble metabolic product-like organic matter (SMP), Eex / Eem is 250-350 nm / 200-380 nm; Region V: humic acid-like substances, Eex / Eem is 250-400 nm / 380-500 nm. The organic matter composition of reverse osmosis concentrated water is complex, mainly composed of tryptophan-like substances (region II) and fulvic acid-like substances (region III).

[0116] Reaction conditions: pH = 8.13, ozone flow rate is 0.03 L / min, catalyst loading is 200 g / L, reaction time is 60 min, and ozone dosage ratio is 1.4.

[0117] The experimental results show that the COD removal rate can reach 42.86%, and the catalyst does not show obvious powder loss during the catalytic process, and the reusability is good. Because the wastewater treatment of this embodiment can meet the discharge requirements, and the ozone dosage ratio of this embodiment is also more economical, the conditions of this embodiment are used in the subsequent research process, therefore, the oxidation effluent of this embodiment is selected for three-dimensional fluorescence spectrum test to analyze the removal effect of organic matter in water, and the three-dimensional fluorescence spectrum of the oxidation effluent is shown in Figure 3 It can be seen from Figure 3 that the spectrum shows that the fluorescence response intensity of each region is further reduced, and the tryptophan-like substances (region II), fulvic acid-like substances (region III), and humic acid-like substances (region V) are completely degraded.

[0118] Comparative Example 1

[0119] An ozone oxidation catalyst with both metal and non-metal active sites is used as a comparison. Aluminum trioxide (3-5 mm) is used as a carrier for catalyst preparation and performance determination.

[0120] (1) Place the catalyst carrier in a beaker, wash it with deionized water for 8 times to remove surface impurities, dry it in a blast drying oven at a temperature of 100°C for 10 h, and then place the dried carrier in a crucible and put it in a muffle furnace at 300°C for 3 h to obtain a pretreated carrier;

[0121] (2) Configuration 0.016 mol / L NaOH solution, 30 g of pretreated carrier and 150 mL of alkaline solution (carrier and alkaline solution dosage ratio is 0.2 g / mL) into a conical flask, after shaking in the shaker for 1 h, add 1.5 g of coating agent, 20℃ in the shaker for 6 h, filter and wash with ultrapure water 3 times, loaded into a culture dish, in the drying oven, set the temperature to 60℃, dry for 6 h, obtain the catalyst precursor;

[0122] (3) The catalyst precursor is placed in a tube furnace, and inert gas protection is passed, and is calcined at 800℃ for 2h to obtain an ozone oxidation catalyst with metal and non-metallic dual active sites.

[0123] The ozone oxidation catalyst is loaded in a wastewater treatment device, wastewater is introduced, and ozone is introduced to perform ozone oxidation treatment on the wastewater:

[0124] The wastewater is reverse osmosis concentrated water of a certain petrochemical industry factory, COD: the COD of the wastewater is 40-60 mg / L, and TDS: 3180-3190 mg / L.

[0125] Reaction conditions: pH = 8.13, ozone flow rate is 0.03 L / min, catalyst loading amount is 200 g / L, reaction time is 60 min, and ozone addition ratio is 1.4.

[0126] The experimental results show that the COD removal rate of the catalyst in the comparative example can only reach 17.68%. The three-dimensional fluorescence spectrum of the oxidation effluent of the comparative example is tested to analyze the removal effect of organic matter in water, and the three-dimensional fluorescence spectrum of the oxidation effluent is shown in Figure 4 From Figure 4 It can be seen that the fluorescence response intensity of each region of the spectrum is reduced, but no region is completely degraded, and the organic matter removal effect cannot achieve the same effect as example 5.

[0127] Comparative example 2:

[0128] An ozone oxidation catalyst with metal and non-metallic dual active sites is used as a comparison. Aluminum oxide (3-5 mm) is used as a carrier to prepare the catalyst and determine the performance.

[0129] (1) The catalyst carrier is placed in a beaker and washed with deionized water for 8 times to remove surface impurities, and dried in a drying oven at a temperature of 100℃ for 10 h. The dried carrier is loaded into a crucible and placed in a muffle furnace and calcined at 300℃ for 3 h to obtain a pretreated carrier;

[0130] (2) 0.05 mol / L NaOH solution was configured, 30 g of the pretreated carrier and 150 mL of the alkaline solution (the carrier to alkaline solution dosage ratio was 0.2 g / mL) were added into a conical flask, after oscillation in a shaking bed for 1 h, 1.5 g of the coating agent was added, oscillation was carried out in a shaking bed at 20℃ for 6 h, filtration was carried out and washing was carried out with ultrapure water for 3 times, the catalyst precursor was obtained by loading into a culture dish, setting the temperature to 60℃ in a blast drying oven, and drying for 6 h;

[0131] (3) The catalyst precursor was placed in a tube furnace, inert gas protection was carried out, and calcination was carried out at 800℃ for 2 h, and the ozone oxidation catalyst with metal and nonmetal dual active sites was obtained.

[0132] The ozone oxidation catalyst was loaded in a wastewater treatment device, wastewater was introduced, and ozone was introduced, and the wastewater was subjected to ozone oxidation treatment:

[0133] The wastewater was reverse osmosis concentrated water of a certain petrochemical industry factory, the COD of the wastewater was 40-60 mg / L, and the TDS was 3180-3190 mg / L.

[0134] The reaction conditions were as follows: pH = 8.13, the ozone flow rate was 0.03 L / min, the catalyst loading amount was 200 g / L, the reaction time was 60 min, and the ozone addition ratio was 2.2.

[0135] The experimental results showed that the COD removal rate of the catalyst in the comparative example could only reach 23.57%.

[0136] It should be noted that the above-described embodiments are only the preferred embodiments of the present application, which are used to explain the present application and do not constitute any limitation on the present application. The present application is described by referring to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than limiting words. The present application can be modified within the scope of the claims of the present application, and the present application can be revised without departing from the scope and spirit of the present application. Although the present application described therein relates to specific methods, materials and embodiments, it does not mean that the present application is limited to the specific examples disclosed therein, on the contrary, the present application can be extended to all other methods and applications with the same function.

Claims

1. A potassium-based ozone oxidation catalyst having a ternary active site, which is composed of a support, a ternary active component supported on the support, wherein, The ternary active component is K, N-C and S-C.

2. The potassium-based ozone oxidation catalyst of claim 1, wherein, The carrier is modified by a surface modification; preferably, the surface modification is a polymerization on the surface of the carrier based on a modifier, with potassium hydroxide as a crosslinking agent and a K precursor, with thiourea as an S precursor, and a K, N-C and S-C ternary active site is constructed simultaneously; further preferably, the modifier is dopamine hydrochloride. 3.A method for preparing a potassium-based ozone oxidation catalyst with a ternary active site, comprising: Step A: washing the carrier with water, drying, calcining, and obtaining a pretreated carrier; Step B: placing the pretreated carrier in an aqueous potassium hydroxide solution, adding a modifier and thiourea, stirring, then filtering, washing, and drying to obtain a dry catalyst precursor; Step C: calcining the dry catalyst precursor to obtain a potassium-based ozone oxidation catalyst with a ternary active site.

4. The production method according to claim 3, characterized by, In step A, the drying is performed under vacuum, the drying temperature is 60-120℃, and the drying time is 6-12h; and / or, the calcining temperature is 200-350℃, and the calcining time is 2-5h. 5.The method according to claim 3, characterized in that, In step B, the modifier is dopamine hydrochloride, and the mass ratio of the modifier to the pretreated carrier is 1:30; and / or, the concentration of the aqueous potassium hydroxide solution is 0.5-1g / L, and the mass ratio of the potassium hydroxide to the pretreated carrier is 1:200-400; and / or, the addition amount of thiourea is 0.75-2.25g / L based on the volume of the aqueous potassium hydroxide solution.

6. The preparation method according to claim 3, characterized in that, In step B, the stirring temperature is 20-35℃, and the stirring time is 6-12h; and / or, the drying is performed under vacuum, the drying temperature is 60-80℃, and the drying time is 6-12h.

7. The preparation method according to claim 3, characterized in that, In step C, the calcining is performed under an inert gas atmosphere, the calcining temperature is 700-900℃, and / or, the calcining time is 2-5h. 8.The ozone oxidation catalyst of any one of claims 1-3 or the ozone oxidation catalyst prepared by the method of any one of claims 4-8 is applied in the advanced treatment of salt-containing organic wastewater.

9. Use according to claim 8, characterized in that, The application comprises loading the ozone oxidation catalyst in a wastewater treatment device, passing in wastewater, and passing in ozone to perform ozone oxidation treatment on the wastewater to obtain oxidized effluent water meeting emission standards. The salt-containing organic wastewater comprises petrochemical wastewater reverse osmosis concentrated water and / or chemical wastewater; the COD of the wastewater is 40-60mg / L, and the TDS is 3180-3190mg / L.

10. Use according to claim 9, characterized in that, The reaction conditions of the ozone oxidation treatment are as follows: the pH of the wastewater is 8.13, the ozone flow rate is 0.03L / min, the catalyst loading amount is 200g / L, the reaction time is 60min, and the ozone addition ratio is 0.8-2.2.

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