Preparation method of passive hydrogen recombiner catalyst based on foam metal

Abstract

The invention relates to the technical field of catalyst preparation, in particular to a preparation method of a passive hydrogen recombiner catalyst based on foam metal. The problem that hydrazine and hydroboron are used as reducing agents in the preparation process is solved. Comprising the steps that firstly, foam metal is soaked in hydrochloric acid, acetone, ethyl alcohol and deionized water in sequence, ultrasonic treatment is conducted at the same time, and the foam metal is washed with deionized water after being soaked and then dried; 2, Pt salt and Pd salt are dissolved in deionized water, ultrasonic treatment is carried out, uniform stirring is carried out, and a precursor solution is obtained; and step 3, soaking the treated foam metal in the precursor solution, washing with deionized water after soaking, and drying in a vacuum drying oven to obtain the nano flower-shaped Pt-Pd bimetallic catalyst after drying. The catalyst is prepared by adopting a chemical platinum and palladium plating method, the use of highly toxic hydrazine and a dangerous article hydroboron as a reducing agent is avoided, the preparation process is simple, and the problems that the preparation of a common catalyst is complicated and the preparation process is possibly toxic are solved.

Description

Technical Field

[0001] The invention relates to the technical field of catalyst preparation, in particular to a method for preparing a passive hydrogen recombiner catalyst based on foamed metal. Background Art

[0002] The passive hydrogen recombiner is a device specially designed for the safety of nuclear power plants. Its purpose is to automatically catalyze the reaction of hydrogen and oxygen to produce water without the need for external energy supply, thereby reducing the hydrogen concentration, preventing explosions and fires caused by hydrogen, and ensuring the safety of nuclear power plants.

[0003] At present, the catalytic plate is mainly composed of catalyst, carrier and substrate, and the design between the catalyst and the carrier is particularly important. At the same time, in the process of preparing the catalyst, highly toxic hydrazine and dangerous borohydride may be used as reducing agents, or reduction may be carried out in a hydrogen and nitrogen mixture at high temperature.

[0004] Therefore, it is urgent to propose an efficient and non-toxic catalyst preparation method to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a simple, efficient, non-toxic passive hydrogen recombiner catalyst based on foamed metal, which solves the problem of using highly toxic hydrazine and dangerous borohydride as reducing agents in the process of preparing the catalyst, and a brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to determine the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0006] The technical solution of the present invention:

[0007] A method for preparing a passive hydrogen recombiner catalyst based on foamed metal comprises the following steps:

[0008] Step 1: Soak the foam metal in hydrochloric acid, acetone, ethanol, and deionized water in sequence, and simultaneously perform ultrasonic treatment. After soaking, rinse the foam metal with deionized water, and dry it after soaking.

[0009] Step 2: dissolving Pt salt and Pd salt in deionized water, performing ultrasonic treatment, and stirring uniformly to obtain a precursor solution;

[0010] Step 3: Soak the treated foam metal in the precursor solution, rinse with deionized water after soaking, and then put it into a vacuum drying oven for drying to obtain a nanoflower-shaped Pt-Pd bimetallic catalyst.

[0011] Preferably, in step 1, the concentration of hydrochloric acid is 0.5-2.0 M, the ethanol is anhydrous ethanol, and the ultrasonic treatment time is 10-30 min.

[0012] Preferably, the Pt source of the precursor solution is chloroplatinic acid hexahydrate, and the Pd source is palladium chloride.

[0013] Preferably, the concentration of Pt ions in the precursor solution is 0.01-5.0 mM, and the concentration of Pd ions is 0.01-3.0 mM.

[0014] Preferably, the immersion time of the foam metal in step 3 is 2-8 hours.

[0015] Preferably, the vacuum drying temperature in step 3 is 40-60° C. and the drying time is 4-8 h.

[0016] The present invention has the following beneficial effects:

[0017] Pt and Pd catalysts have high catalytic activity and can efficiently catalyze the reaction between hydrogen and oxygen and quickly reduce the hydrogen concentration;

[0018] Pt and Pd catalysts can work at room temperature and have strong adaptability to the environment;

[0019] Metal foams have a high specific surface area, which helps provide more active sites and thus improve catalytic efficiency;

[0020] The pore structure of metal foam can provide channels for reactants and products, which helps to improve the efficiency of material transmission;

[0021] The pore size, shape and chemical composition of metal foams can be adjusted as needed to suit different catalytic reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a SEM image of the Pt1-Pd1 / NF catalyst prepared in Example 1;

[0023] Figure 2 is a SEM image of the Pt2-Pd1 / NF catalyst prepared in Example 2;

[0024] Figure 3 is a SEM image of the Pt1-Pd2 / NF catalyst prepared in Example 3;

[0025] Figure 4 is a scanning electron microscope (SEM) image of the pretreated nickel foam;

[0026] Figure 5 is the X-ray diffraction (XRD) pattern of the Pt-Pd / NF catalyst prepared in Example 1-3;

[0027] Figure 6 This is a graph showing the catalytic capacity of the Pt1-Pd1 / NF catalyst prepared in Example 1 under different hydrogen concentrations. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0029] Specific implementation method 1: Combination Figure 1-Figure 6 To illustrate this embodiment, a method for preparing a passive hydrogen recombiner catalyst based on foamed metal in this embodiment comprises the following steps;

[0030] Step 1: Soak the foam metal in hydrochloric acid, acetone, ethanol, and deionized water in sequence, and simultaneously perform ultrasonic treatment. After soaking, rinse the foam metal with deionized water, and dry it after soaking.

[0031] Step 2: dissolving Pt salt and Pd salt in deionized water, performing ultrasonic treatment, and stirring uniformly to obtain a precursor solution;

[0032] Step 3: Soak the treated foam metal in the precursor solution, rinse it with deionized water, and then put it into a vacuum drying oven to dry it. After drying, a nanoflower-shaped Pt-Pd bimetallic catalyst is obtained. This catalyst exhibits excellent activity in catalytic reactions due to its unique nanostructure and bimetallic effect, and has broad application prospects.

[0033] Specific implementation method 2: This implementation method is a method for preparing a passive hydrogen recombiner catalyst based on foam metal. The foam metal in step 1 includes but is not limited to foam nickel, foam copper, foam aluminum, foam nickel iron, and foam titanium dioxide.

[0034] Specific implementation method three: Combination Figure 1 The present embodiment is described as a method for preparing a passive hydrogen recombiner catalyst based on foam metal. In step 1, the concentration of hydrochloric acid is 0.5-2.0 M, ethanol is anhydrous ethanol, and the ultrasonic treatment time is 10-30 min to thoroughly clean the surface of the foam metal.

[0035] Specific embodiment 4: This embodiment is a method for preparing a passive hydrogen recombiner catalyst based on foam metal, wherein the platinum salt includes but is not limited to potassium chloroplatinate, chloroplatinic acid, and platinum acetylacetonate; the palladium salt includes but is not limited to palladium nitrate, palladium chloride, and platinum acetylacetonate.

[0036] Specific implementation mode 5: In the present implementation mode, a method for preparing a passive hydrogen recombiner catalyst based on foamed metal is provided, wherein the concentration of platinum ions in the precursor solution is 0.01-5.0 mM, and the concentration of palladium ions is 0.01-3.0 mM.

[0037] Specific implementation method six: In this implementation method, a passive hydrogen recombiner catalyst based on foamed metal is prepared. In step three, the immersion time of the foamed metal is 2-8 hours, and a catalyst with a desired deposition amount and good morphology can be prepared.

[0038] Specific implementation method seven: In this implementation method, a foam metal-based passive hydrogen recombiner catalyst is prepared. In step three, the vacuum drying temperature is 40-60°C and the drying time is 4-8h. The drying temperature and drying time are controlled to ensure the quality and performance of the catalyst.

[0039] Example 1

[0040] Taking nickel foam as an example, the pretreatment of the foam metal includes the following steps:

[0041] Step 1: Cut the nickel foam into the required size, then soak it in a 1M hydrochloric acid aqueous solution, and place the whole in an ultrasonic bath for 15 minutes to remove surface impurities;

[0042] Step 2: After the ultrasonic treatment, take out the nickel foam and rinse it with deionized water, then soak it in acetone and ultrasonicate it again for 15 minutes;

[0043] Step 3: After the ultrasonic treatment, take out the nickel foam and rinse it with deionized water, then soak it in ethanol and ultrasonicate it again for 15 minutes;

[0044] Step 4: After the ultrasonic wave is completed, take out the nickel foam with tweezers and rinse it with deionized water, then immerse it in deionized water and ultrasonicate it again for 15 minutes. After the ultrasonic wave is completed, take it out and dry it for later use;

[0045] Prepare 50 mL of an aqueous solution with a concentration of 1 mM chloroplatinic acid and 1 mM palladium chloride, ultrasonically stir the solution to make a homogeneous solution, and then soak the pretreated nickel foam block in the homogeneous solution for 4 hours. After soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum drying oven at 60°C for 4 hours to obtain a Pt1-Pd1 / NF catalyst.

[0046] Example 2

[0047] The nickel foam pretreatment step is consistent with that in Example 1;

[0048] Prepare 50 mL of an aqueous solution with a concentration of 2 mM chloroplatinic acid and 1 mM palladium chloride, sonicate and stir the solution to make a homogeneous solution, then soak the pretreated nickel foam pieces in the homogeneous solution for 5 hours. After the soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum drying oven at 60°C and dry it for 4 hours to obtain the Pt2-Pd1 / NF catalyst.

[0049] Example 3

[0050] The nickel foam pretreatment step is consistent with that in Example 1;

[0051] Prepare 50 mL of an aqueous solution with a concentration of 1 mM chloroplatinic acid and 2 mM palladium chloride, sonicate and stir the solution to make a homogeneous solution, then soak the pretreated nickel foam pieces in the homogeneous solution for 6 hours. After the soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum drying oven at 60°C and dry it for 4 hours to obtain the Pt1-Pd2 / NF catalyst.

[0052] Example 4

[0053] The nickel foam pretreatment step is consistent with that in Example 1;

[0054] Prepare 50 mL of an aqueous solution with a concentration of 3 mM potassium chloroplatinate and 1 mM palladium chloride, ultrasonically and stir the solution to make a homogeneous solution, and then soak the pretreated nickel foam pieces in the homogeneous solution for 4 hours. After the soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum dryer at 60°C for 4 hours to obtain a Pt3-Pd1 / NF catalyst.

[0055] Example 5

[0056] The nickel foam pretreatment step is consistent with that in Example 1;

[0057] Prepare 50 mL of an aqueous solution with a concentration of 1 mM potassium chloroplatinate and 3 mM palladium nitrate, sonicate and stir the solution to make a homogeneous solution, then soak the pretreated nickel foam pieces in the homogeneous solution for 5 hours. After the soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum dryer at 60°C for 4 hours to obtain a Pt1-Pd3 / NF catalyst.

[0058] Example 6

[0059] The nickel foam pretreatment step is consistent with that in Example 1;

[0060] Prepare 50 mL of an aqueous solution with a concentration of 2 mM platinum acetylacetonate and 2 mM palladium acetylacetonate, sonicate and stir the solution to make a homogeneous solution, then soak the pretreated nickel foam pieces in the homogeneous solution for 6 hours. After the soaking, take out the nickel foam, rinse it with deionized water, and then put it into a vacuum dryer at 60°C for 4 hours to obtain a Pt2-Pd2 / NF catalyst.

[0061] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a passive hydrogen recombiner catalyst based on foamed metal, characterized in that: The method comprises the following steps: Step 1: Soak the foam metal in hydrochloric acid, acetone, ethanol, and deionized water in sequence, and simultaneously perform ultrasonic treatment. After soaking, rinse the foam metal with deionized water, and dry it after soaking. Step 2: Prepare a precursor solution using Pt salt, Pd salt and deionized water; Step 3: Soak the treated foam metal in the precursor solution, rinse with deionized water after soaking, and then put it into a vacuum drying oven for drying to obtain a nanoflower-shaped Pt-Pd bimetallic catalyst.

2. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: The foam metal is one of foam nickel, foam copper, foam aluminum, foam nickel iron, and foam titanium dioxide.

3. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: The concentration of hydrochloric acid is 0.5-2.0 M, the ethanol is anhydrous ethanol, and the ultrasonic treatment time is 10-30 min.

4. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: The Pt salt is one of potassium chloroplatinate, chloroplatinic acid, and platinum acetylacetonate; the Pd salt is one of palladium nitrate, palladium chloride, and palladium acetylacetonate.

5. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: When preparing the precursor solution, first weigh the Pt salt and the Pd salt, add them into deionized water, and prepare a homogeneous precursor solution by stirring, ultrasonic treatment, etc.

6. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: The concentration of Pt ions in the precursor solution is 0.01-5.0 mM, and the concentration of Pd ions is 0.01-3.0 mM.

7. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: The immersion time of the foam metal in step 3 is 2-8 hours.

8. The method for preparing a passive hydrogen recombiner catalyst based on foamed metal according to claim 1, characterized in that: In step 3, the vacuum drying temperature is 40-60°C and the drying time is 4-8h.

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