Liquid phase self-oxidation type platinum-manganese-copper ternary ozone catalyst and preparation method thereof

Abstract

The present application relates to the technical field of water treatment catalyst, and relates to a platinum-manganese-copper ternary ozone catalyst with a metal oxide active layer directly synthesized by an oxidizing solution and a preparation method thereof.The preparation method comprises the following steps: adding a metal salt solution containing Pt, Mn and Cu into a suspension liquid of a pretreated oxidizing carrier; in a gradient adding mode of an oxidizing agent, the initial oxidizing agent concentration is controlled to be 0.1-0.5 mol / L, three-stage supplement is performed, and the oxidizing rate is controlled to be less than or equal to 0.8 mmol / min; the catalyst comprises a carrier gamma-Al2O3 and an active layer loaded on the surface of the carrier, and the active layer is composed of PtO2, MnO2 and CuO.The catalyst prepared by the preparation method of the present application has excellent performance in coking wastewater treatment, can efficiently degrade various pollutants in the wastewater, and has a wide application prospect; the energy consumption can be reduced by more than 65%, and the energy consumption and production cost are greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of water treatment catalyst technology, specifically to a platinum-manganese-copper ternary ozone catalyst and its preparation method, which directly synthesizes a metal oxide active layer through an oxidizing solution. Background Technology

[0002] In the field of industrial wastewater treatment, especially coking wastewater treatment, the performance and preparation method of catalysts have a crucial impact on treatment efficiency and cost. Currently, traditional catalyst preparation methods have many shortcomings.

[0003] Currently, among the commonly used methods for preparing water treatment catalysts in industrial production, calcination requires high temperatures (>500℃), leading to extremely high energy consumption. Furthermore, the high temperatures cause metal particles to sinter, increasing their size (typically >20nm), thus reducing catalyst activity and stability, and resulting in environmental pollution from the generated waste gas. While chemical deposition avoids some of the problems associated with high-temperature calcination, this method is cumbersome, requiring multiple washing operations, which increases process complexity and significantly increases wastewater discharge. Methods for preparing catalysts by forming an active layer on a support surface through solution oxidation are rarely reported. Moreover, the lack of effective control techniques for the co-oxidation process of noble and transition metals makes it difficult to prepare catalysts with excellent and stable performance.

[0004] Therefore, there is an urgent need to develop a new catalyst preparation method to overcome the shortcomings of existing technologies and improve the performance and efficiency of catalysts in coking wastewater treatment. Summary of the Invention

[0005] The purpose of this invention is to provide a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst and its preparation method, so as to solve the problems mentioned in the background art.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for preparing a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst includes the following steps:

[0008] (1) Add the metal salt solution containing Pt, Mn and Cu to the pretreated suspension containing an oxidizing carrier;

[0009] (2) The oxidant was added in a gradient manner, with the initial oxidant concentration controlled at 0.1-0.5 mol / L, and added in three stages to control the oxidation rate ≤0.8 mmol / min.

[0010] Preferably, the oxidant is a chlorate / hydrogen peroxide composite system, wherein the molar ratio of NaClO3 to H2O2 is 1-5:1.

[0011] The present invention patent application also discloses a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst prepared by the above-mentioned preparation method of a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst. The catalyst comprises a support γ-Al2O3 and an active layer supported on the surface of the support, wherein the active layer is composed of PtO2, MnO2 and CuO.

[0012] Preferably, the active components contain 0.01-1 wt% Pt, 0.1-2 wt% Mn, and 0.1-2 wt% Cu.

[0013] Preferably, the active components contain 0.06 wt% Pt, 1.6 wt% Mn, and 1.7 wt% Cu.

[0014] Compared with the prior art, the advantages of the liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst and its preparation method of the present invention are as follows:

[0015] 1. Catalyst performance advantages: The liquid-phase self-oxidation type platinum-manganese-copper ternary ozone catalyst prepared by this patent application has excellent performance in coking wastewater treatment; the catalyst has been tested in pilot-scale tests and the COD removal rate can be kept stable at 2000mg / L under the condition of fluctuating influent COD, and the treatment effect is efficient and stable, and is not affected by chloride ion concentration.

[0016] 2. Advantages of the preparation process: energy saving and consumption reduction. The liquid phase self-oxidation process adopted in this patent application avoids the high-temperature process required by the traditional calcination method. Compared with the traditional calcination method, it can reduce energy consumption by more than 65%, which greatly reduces energy consumption and production costs.

[0017] 3. Controllable Structure: By precisely controlling the gradient addition of oxidant, the thickness of the active layer can be accurately controlled. Furthermore, the catalyst prepared using this method possesses unique microstructural advantages: layered MnO2 and PtO2 form a PN junction, reducing electrochemical impedance by 40% and effectively improving electron transport efficiency; the CuO embedded structure enhances the catalyst's resistance to sulfur poisoning, further extending its service life.

[0018] 4. Structural Advantages: The catalyst prepared according to this patent application possesses a unique microstructure. The PN junction formed by layered MnO2 and PtO2 optimizes the electron transport path and improves the electron transfer efficiency of the catalytic reaction; the embedded structure of CuO enhances the catalyst's resistance to poisons such as sulfides, effectively solving the problem of traditional catalysts being easily poisoned and deactivated. These structural advantages enable the catalyst of this invention to exhibit excellent performance in coking wastewater treatment, efficiently degrading various pollutants in the wastewater and showing broad application prospects. Detailed Implementation

[0019] The following are specific embodiments of the present invention, which further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0020] Example 1: A method for preparing a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst, comprising the following steps:

[0021] (1) Add the metal salt solution containing Pt, Mn and Cu to the pretreated suspension containing an oxidizing carrier;

[0022] (2) The oxidant was added in a gradient manner, with the initial oxidant concentration controlled at 0.1-0.5 mol / L, and added in three stages to control the oxidation rate ≤0.8 mmol / min;

[0023] The oxidant mentioned above is a chlorate / hydrogen peroxide composite system, wherein the molar ratio of NaClO3 to H2O2 is 1-5:1.

[0024] The present invention patent application also discloses a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst prepared by the above-mentioned preparation method of a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst. The catalyst comprises a support γ-Al2O3 and an active layer supported on the surface of the support, wherein the active layer is composed of PtO2, MnO2 and CuO.

[0025] The active components contain 0.01 wt% Pt, 0.1 wt% Mn, and 0.1 wt% Cu.

[0026] Example 2: A method for preparing a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst, comprising the following steps:

[0027] (1) Add the metal salt solution containing Pt, Mn and Cu to the pretreated suspension containing an oxidizing carrier;

[0028] (2) The oxidant was added in a gradient manner, with the initial oxidant concentration controlled at 0.1-0.5 mol / L, and added in three stages to control the oxidation rate ≤0.8 mmol / min;

[0029] The oxidant mentioned above is a chlorate / hydrogen peroxide composite system, wherein the molar ratio of NaClO3 to H2O2 is 1-5:1.

[0030] The present invention patent application also discloses a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst prepared by the above-mentioned preparation method of a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst. The catalyst comprises a support γ-Al2O3 and an active layer supported on the surface of the support, wherein the active layer is composed of PtO2, MnO2 and CuO.

[0031] The active components contain 0.06 wt% Pt, 1.6 wt% Mn, and 1.7 wt% Cu.

[0032] Example 3: This Example 3 differs from Examples 1 and 2 in that the liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst disclosed in this patent application comprises a support γ-Al2O3 and an active layer supported on the surface of the support. The active layer is composed of PtO2, MnO2 and CuO; wherein the active components contain 1 wt% Pt, 2 wt% Mn and 2 wt% Cu.

[0033] (I) Catalyst Preparation

[0034] Carrier pretreatment: 5 mm γ-Al2O3 microspheres were used as carriers, and 10% nitric acid was used to activate the γ-Al2O3 carriers to increase the number of active sites and surface properties on the carrier surface, and enhance the binding ability of the carrier to the active components.

[0035] Oxidation solution preparation: A mixed solution of NaClO3 / H2O2 was selected as the oxidant, with a molar ratio of 3:1. This composite oxidant provides stable and suitable oxidation power, ensuring sufficient oxidation of the metal salt while avoiding the introduction of excessive impurities. H2PtCl6・6H2O, MnSO4, and Cu(NO3)2 were weighed, with a molar ratio of Pt, Mn, and Cu of 1:2:2, to prepare the metal salt solution.

[0036] In-situ oxidation: The prepared metal salt solution was added to a support containing pretreated γ-Al₂O₃, and an oxidizing agent was added simultaneously to initiate the in-situ oxidation reaction. During the reaction, the reaction temperature was controlled at 65-90℃ to ensure the oxidation efficiency of manganese and the stability of the reaction. Stirring speed ensured uniform mixing of the reaction system, allowing the metal salt and oxidant to fully contact and react. The oxidant was added in a gradient. After the reaction, the product was centrifuged to remove excess solution. Then, the separated product was washed with ethanol to remove residual impurities and anions. Finally, the washed product was placed in a vacuum drying oven and dried at 80℃ for 6 hours to obtain the final platinum-manganese-copper ternary ozone catalyst.

[0037] Liquid phase self-oxidation process:

[0038] This patent application proposes a novel liquid-phase self-oxidation process for preparing platinum-manganese-copper ternary ozone catalysts. This process eliminates the traditional high-temperature calcination and cumbersome chemical deposition steps, directly oxidizing platinum, manganese, and copper-containing metal salts on the support surface through an oxidizing solution to form a metal oxide active layer. This process not only reduces energy consumption during preparation but also effectively controls the structure and performance of the active layer, laying the foundation for the catalyst to exert its high-efficiency effect in coking wastewater treatment.

[0039] Oxidation control technology:

[0040] The oxidant is added in a gradient manner during the reaction. Initially, the oxidant concentration is controlled within the range of 0.1-0.5 mol / L, and then the oxidant is added gradually in three stages. In this way, the oxidation rate is precisely controlled to not exceed 0.8 mmol / min, ensuring that the metal salt can be oxidized uniformly and stably, and avoiding uneven active layer structure caused by excessively rapid oxidation.

[0041] Temperature synergy, controlling the reaction temperature between 55-95℃, revealed that manganese oxidation efficiency could increase by 2.3 times when the temperature exceeded 60℃. Through the synergistic effect of temperature and other control parameters, precise regulation of the metal oxidation process was achieved, improving the overall performance of the catalyst.

[0042] Catalyst performance advantages:

[0043] The platinum-manganese-copper ternary ozone catalyst prepared according to this patent application has significant advantages in the treatment of coking wastewater. In its active component, Pt, as an electron transport center, efficiently promotes electron transfer and accelerates the catalytic reaction process; MnO2 constructs abundant oxygen vacancies, promoting the generation of ·OH free radicals and enhancing the oxidation capacity of organic matter in the wastewater; CuO enhances the adsorption capacity for macromolecular organic matter, enabling more effective catalytic degradation of macromolecular organic matter. Furthermore, chloride ion concentration is a key factor affecting the service life of traditional catalysts; this catalyst exhibits excellent resistance to chloride and poisoning, thereby extending its service life.

[0044] Technological Breakthrough: This patent application breaks through the limitations of traditional catalyst preparation processes, proposing and successfully realizing the preparation of a platinum-manganese-copper ternary ozone catalyst via a liquid-phase self-oxidation process for the first time. This process eliminates the need for high-temperature calcination and cumbersome chemical deposition steps, simplifying the preparation process and reducing energy consumption and wastewater discharge, demonstrating significant environmental and economic value. Simultaneously, through innovative oxidation control technology, precise regulation of the metal oxidation process is achieved, providing a new approach for preparing high-performance catalysts.

[0045] Experimental data: Pilot-scale testing demonstrated that, regardless of fluctuations in the COD of the coking wastewater influent, the COD degradation remained stable at 2000 mg / L over the 70-day test period, with an average COD removal rate of 41.5%. Thiocyanate, cyanide, and volatile phenols were all degraded to varying degrees, significantly improving the biodegradability of the wastewater.

[0046] Contents not described in detail herein are existing technologies known to those skilled in the art. The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for preparing a liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst, characterized in that, Includes the following steps: (1) Add the metal salt solution containing Pt, Mn and Cu to the suspension containing the pretreated γ-alumina support; (2) The oxidant was added in a gradient manner, with the initial oxidant concentration controlled at 0.1-0.5 mol / L, and added in three stages to control the oxidation rate ≤0.8 mmol / min; The oxidant is a sodium chlorate / hydrogen peroxide composite system, wherein the molar ratio of NaClO3 to H2O2 is 1-5:

1.

2. The liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst prepared by the method according to claim 1, characterized in that, The catalyst comprises a support γ-Al2O3 and an active layer supported on the surface of the support, the active layer being composed of PtO2, MnO2 and CuO.

3. The liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst according to claim 2, characterized in that, The content of Pt is 0.01-1wt%, the content of Mn is 0.1-2wt%, and the content of Cu is 0.1-2wt%.

4. The liquid-phase self-oxidizing platinum-manganese-copper ternary ozone catalyst according to claim 3, characterized in that, The content of Pt is 0.06 wt%, the content of Mn is 1.6 wt%, and the content of Cu is 1.7 wt%.