阅读说明：本技术 氢燃料电池废旧催化剂浆料的回收方法 (Method for recovering waste catalyst slurry of hydrogen fuel cell ) 是由 钟发平 倪江鹏 杨涵 贺凤 邓宇飞 尹涛 于 2020-06-18 设计创作，主要内容包括：本发明提供了一种氢燃料电池废旧催化剂浆料的回收方法,首先往废旧催化剂浆料中添加碱性溶液使得浆料的PH值控制在10以上,之后将调整好PH值的浆料加热至60～100℃并保持该温度1h以上,接着将浆料在一定环境温度下静置,直至浆料中的固态物质完成沉降,最后将上层清液直接回收作为膜电极制备时的清洗液,将下层沉降物质在使用去离子水冲洗后干燥形成固态物质粉末。本发明方法简单易行,可避免环境污染。(The invention provides a method for recovering waste catalyst slurry of a hydrogen fuel cell, which comprises the steps of firstly adding an alkaline solution into the waste catalyst slurry to control the pH value of the slurry to be more than 10, then heating the slurry with the adjusted pH value to 60-100 ℃ and keeping the temperature for more than 1h, then standing the slurry at a certain environmental temperature until solid substances in the slurry are settled, finally directly recovering supernatant as cleaning liquid during membrane electrode preparation, and drying the settled substances at the lower layer after washing with deionized water to form solid substance powder. The method is simple and easy to implement, and can avoid environmental pollution.)

1. A method for recovering waste catalyst slurry of a hydrogen fuel cell is characterized by comprising the following steps: firstly, adding an alkaline solution into waste catalyst slurry to control the pH value of the slurry to be more than 10, then heating the slurry with the adjusted pH value to 60-100 ℃ and keeping the temperature for more than 1h, then standing the slurry at a certain environmental temperature until solid substances in the slurry are settled, finally directly recovering supernatant as cleaning liquid during membrane electrode preparation, and drying the settled substances at the lower layer after washing with deionized water to form solid substance powder.

2. The method for recycling the spent catalyst slurry for hydrogen fuel cells according to claim 1, wherein: the alkaline solution is a sodium carbonate solution, a potassium carbonate solution, a sodium hydroxide solution or a potassium hydroxide solution, and the mass concentration of the alkaline solution is 10-20%.

3. The method for recycling the spent catalyst slurry of hydrogen fuel cells according to claim 2, characterized in that: during the addition of the alkaline solution, the slurry needs to be stirred at high speed at the same time.

4. The method for recycling the waste catalyst slurry of the hydrogen fuel cell according to any one of claims 1 to 3, characterized by comprising: the standing environment temperature is 10-30 ℃.

5. The method for recycling the waste catalyst slurry of the hydrogen fuel cell according to any one of claims 1 to 3, characterized by comprising: the waste catalyst slurry is waste catalyst slurry generated in the membrane electrode preparation process and the equipment cleaning process.

Technical Field

The invention relates to a method for recovering waste catalyst slurry of a hydrogen fuel cell.

Background

The core component of the fuel cell is a membrane electrode, which generally adopts noble metal Pt as a catalyst. Since Pt is expensive and scarce, it is necessary to recover Pt as much as possible to realize resource recycling. In the process of preparing the membrane electrode and cleaning equipment and accessories, a large amount of waste Pt-containing catalyst slurry can be generated, and if the Pt-containing catalyst slurry is directly discharged, not only is the Pt greatly wasted, but also the environment is polluted. At present, the recycling channel and the process of the catalyst slurry of the fuel cell are imperfect, and the catalyst slurry containing Pt is generally heated and distilled to remove the solvent according to the traditional method, and then the residue is recycled. However, the solid content of the waste Pt-containing catalyst slurry is low, generally below 1%, the time required for direct distillation treatment is long and the efficiency is low, and secondly, a large amount of organic solvent vapor is generated, which causes environmental pollution.

Disclosure of Invention

The invention aims to provide a simple and feasible method for recovering waste catalyst slurry of a hydrogen fuel cell, which can avoid environmental pollution.

The invention is realized by the following scheme:

a method for recycling waste catalyst slurry of a hydrogen fuel cell comprises the steps of firstly adding an alkaline solution into the waste catalyst slurry to control the pH value of the slurry to be more than 10, so that ionomer in the catalyst slurry is flocculated, then heating the slurry with the adjusted pH value to 60-100 ℃, and keeping the temperature for more than 1h to promote the flocculation of the ionomer and the agglomeration of catalyst particles, wherein the flocculation of the ionomer also promotes the agglomeration and sedimentation of the catalyst particles; and then standing the slurry at a certain environmental temperature until solid substances in the slurry are settled, finally directly recovering supernatant as cleaning liquid in membrane electrode preparation, and washing the lower settled substance with deionized water and then drying to form solid substance powder. In actual production, after the pH value of the slurry meets the requirement, the slurry is generally continuously stirred for more than 10min by magnetic force; the solid mass powder can be subsequently refined to obtain Pt metal according to the Pt refining process of the prior art. After multiple tests, the slurry is stood for more than 8 hours, and the solid substances in the slurry can be settled. The frequency of washing the lower-layer sediment material by using deionized water can be adjusted and designed according to needs, and is generally 1-3 times; the drying process generally comprises: and drying the lower-layer settled substance in an oven at the temperature of 60-80 ℃ for 1-2 h.

Further, the alkaline solution is a sodium carbonate solution, a potassium carbonate solution, a sodium hydroxide solution or a potassium hydroxide solution, and the mass concentration of the alkaline solution is 10-20%.

Further, during the addition of the alkaline solution, the slurry needs to be simultaneously stirred at a high speed. In practical production, the stirring mode is generally magnetic stirring.

Further, the standing environment temperature is 10-30 ℃.

Further, the waste catalyst slurry is waste catalyst slurry generated in membrane electrode preparation process and equipment cleaning process, solid substances in the slurry are catalyst particles and ionomer generally, a solvent of the slurry is a conventional water-alcohol mixed solvent generally, and the catalyst particles are Pt/C particles generally.

The method for recovering the waste catalyst slurry of the hydrogen fuel cell is simple and easy to implement, facilitates batch centralized treatment of the catalyst slurry, can settle solid substances in the catalyst slurry through flocculation of ionomer and agglomeration of catalyst particles by controlling the pH value and the temperature of the slurry, avoids solvent volatilization caused by a distillation method in the prior art, avoids environmental pollution, and can recover and reuse the solvent.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the description of the examples.