JP-7854940-B2 - Cathode catalyst layer, organic hydride production apparatus, and method for preparing cathode catalyst ink.

Inventors

• 高村 徹
• 兼澤 みゆき
• 松岡 孝司
• 宗内 篤夫

Assignees

• ＥＮＥＯＳ株式会社

Dates

Publication Date

20260507

Application Date

20211029

Priority Date

20201030

Claims (4)

1. A cathode catalyst layer that hydrogenates a hydride with protons to produce an organic hydride, The system comprises a cathode catalyst for hydrogenating the substance to be hydrogenated, and a water-repellent agent composed of aggregates of any type of primary particles that have a higher affinity for the substance to be hydrogenated and the organic hydride than for water. The volume fraction of the water-repellent agent in the cathode catalyst layer is 15 vol% or more and 70 vol% or less relative to the total volume of solids in the cathode catalyst layer. Cathode catalyst layer.
2. The cathode catalyst layer contains a porous catalyst support on which the cathode catalyst is supported. The cathode catalyst layer according to claim 1.
3. An electrolyte membrane having a first surface and a second surface facing each other, which moves protons, A cathode provided on the first surface side of the electrolyte membrane, having the cathode catalyst layer according to claim 1 or 2, The electrolyte membrane comprises an anode provided on the second surface side, which oxidizes water to generate protons, Organic hydride manufacturing equipment.
4. A method for preparing a cathode catalyst ink used in a cathode catalyst layer that hydrogenates a hydride with protons to produce an organic hydride, The cathode catalyst and solvent are mixed to prepare the first solution. A dispersion of any type of primary particles having a higher affinity for the hydrogenated substance and the organic hydride than for water , wherein the dispersion is added to the first solution in an amount such that the volume fraction of the water repellent in the cathode catalyst layer is 15 vol% or more and 70 vol% or less relative to the total volume of solids in the cathode catalyst layer, to prepare a second solution. This includes agglomerating the primary particles in the second solution to form a water-repellent agent which has a higher affinity for the hydrogenated substance and the organic hydride than for water and is composed of aggregates of the primary particles. Method for preparing cathode catalyst ink.

Description

This invention relates to a cathode catalyst layer, an organic hydride production apparatus, and a method for preparing a cathode catalyst ink. In recent years, the use of renewable energy sources such as solar, wind, hydroelectric, and geothermal power generation has been anticipated as a way to reduce carbon dioxide emissions during energy production. For example, a system has been devised that uses electricity derived from renewable energy to electrolyze water and produce hydrogen. Furthermore, organic hydride systems are attracting attention as energy carriers for large-scale transportation and storage of hydrogen derived from renewable energy. Regarding the technology for producing organic hydrides, an organic hydride production apparatus is known that comprises an oxidation electrode that generates protons from water and a reduction electrode that hydrogenates organic compounds having unsaturated bonds (see, for example, Patent Document 1). In this organic hydride production apparatus, water is supplied to the oxidation electrode and the substance to be hydrogenated is supplied to the reduction electrode, and an electric current is passed between the oxidation electrode and the reduction electrode, thereby adding hydrogen to the substance to be hydrogenated and producing an organic hydride. International Publication No. 2012/091128 This is a cross-sectional view of an organic hydride production apparatus according to an embodiment.Figure 2(a) is an SEM image of the surface of the cathode catalyst layer according to Example 1. Figure 2(b) is an SEM image of the cross-section of the cathode catalyst layer according to Example 1.Figure 3 is an SEM image of the surface of the cathode catalyst layer according to Comparative Example 1.Figure 4(a) is an SEM image of the surface of the cathode catalyst layer according to Comparative Example 2. Figure 4(b) is an SEM image of the cross-section of the cathode catalyst layer according to Comparative Example 2.Figure 5(a) is an SEM image of the surface of the cathode catalyst layer according to Comparative Example 3. Figure 5(b) is an SEM image of the cross-section of the cathode catalyst layer according to Comparative Example 3.This figure shows the relationship between the toluene concentration in the cathode solution and the Faraday efficiency of the organic hydride production apparatus.This figure shows the properties of the cathode catalyst layer and the performance of the organic hydride production apparatus in Test Examples 1 to 23. The present invention will be described below with reference to the drawings, based on preferred embodiments. The embodiments are illustrative and not limiting, and not all features or combinations thereof described in the embodiments are necessarily essential to the invention. The same or equivalent components, members, and processes shown in each drawing are denoted by the same reference numerals, and redundant explanations are omitted as appropriate. Furthermore, the scale and shape of each part shown in each figure are set for convenience to facilitate explanation and are not to be interpreted restrictively unless otherwise specified. In addition, when terms such as "first," "second," etc. are used in this specification or claims, these terms do not indicate any order or importance, but are used to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted in each drawing. Figure 1 is a cross-sectional view of an organic hydride production apparatus 1 according to an embodiment. In Figure 1, the shapes of each part are simplified in the illustration. The organic hydride production apparatus 1 is an electrolytic cell (electrolytic cell) that hydrogenates the material to be hydrogenated by an electrochemical reduction reaction, and its main components include an electrolyte membrane 2, a cathode 4, an anode 6, and a pair of end plates 8. The electrolyte membrane 2, cathode 4, anode 6, and the pair of end plates 8 are each approximately flat or thin film in shape. The electrolyte membrane 2 is positioned between the cathode 4 and the anode 6 and is a membrane that moves protons from the anode 6 side to the cathode 4 side. The electrolyte membrane 2 has a first surface 2a and a second surface 2b that face each other, with the first surface 2a facing the cathode 4 and the second surface 2b facing the anode 6. The electrolyte membrane 2 is composed of, for example, a solid polymer electrolyte membrane having proton conductivity. The solid polymer electrolyte membrane is not particularly limited as long as it is made of a material that conducts protons, but examples include fluorine-based ion exchange membranes having sulfonic acid groups, such as Nafion (registered trademark). The electrolyte membrane 2 selectively conducts protons while suppressing the mixing or diffusion of substances between the cathode 4 and the anode 6. The thickness of the electr