KR20230089282A - Pt-Ru-Ti catalyst electrode for ballast water electrolysis - Google Patents

Abstract

The present invention is a ballast water electrolysis electrode for sterilizing ballast water, comprising at least one selected from metal mesh, metal foam and metal plate, and Pt, Ru and Ti catalyst layers are located on top of them, The combined molar ratio of Pt:Ru in the catalyst layer is 1:9 to 9:1, and the molar ratio of (Pt:Ru):Ti is 1:1 to 3, and the amounts of Pt, Ru, and Ti catalysts loaded on the electrode for electrolysis are It relates to an electrode for ballast water electrolysis comprising 0.5 to 5 mg/cm ² .
The electrode for ballast water electrolysis according to the present invention does not decrease chlorine oxidation efficiency even in competition with water oxidation and shows a selectivity of 98% or more for generation of active chlorine species. In addition, since the catalyst layer is prepared by reducing the content of precious metals, there is an advantage in securing economic feasibility of the catalyst.

Description

Pt-Ru-Ti catalyst electrode for ballast water electrolysis}

The present invention relates to a Pt-Ru-Ti catalyst electrode for ballast water electrolysis and a manufacturing method thereof, and more particularly, to a Pt-Ru-Ti catalyst electrode for ballast water electrolysis comprising platinum, ruthenium and titanium catalyst layers. And it relates to a manufacturing method thereof.

In general, ballast water refers to seawater filled in a ship for safe and efficient operation of the ship. When a ship unloads its cargo, it rises above the water by the reduced weight, and as the center of gravity increases accordingly, the left and right shaking increases. Operating in this condition may lead to a rollover accident. In addition, if a lot of cargo is loaded on only one side of the ship, the ballast tank on the opposite side is filled with water to balance the left and right sides. Furthermore, ballast water is also necessary to increase the operation efficiency of a ship, because the ship must be submerged to a certain extent so that the propeller can operate under the water surface, so that the ship can operate efficiently. Although ballast water is essential for ship operation, it has a stigma as a major culprit in the destruction of marine ecosystems today, and various marine organisms included in ballast water may move to the coasts of other countries and disturb the ecosystem. Due to these problems, it has become mandatory to install a ballast water treatment system on new ships built after 2012 and on all ships currently operating after 2017, and accordingly, an efficient technology for ballast water treatment is required. As a general ballast water treatment technology, various treatment methods such as electrolysis (straight pipe type, side stream type), ultraviolet (UV), ozone, filter method, centrifugal separation, and heat treatment have been proposed. The most recently adopted method is the electrolysis method, of which the direct electrolysis method is used to disinfect ballast water through direct disinfection by hypochlorous acid (HClO, NaClO), OH radicals, or potential difference generated by electrolyzing seawater. method of sterilization. The conventional direct electrolysis method uses an electrolysis process in which oxygen or chlorine is generated, such as a seawater decomposition process, and uses a metal titanium as a substrate to form an electrode active material (oxides of platinum group metals such as iridium (Ir) and ruthenium (Ru)) on the substrate surface. It is common to use an electrode prepared by depositing a catalyst layer). Catalyst layers such as oxides of platinum group metals such as iridium and ruthenium are used to induce high chlorine production and reduction reactions, and these electrodes are commonly called DSA electrodes and are currently used in various chlor-alkali industries as well as ballast water treatment. However, there is a problem in that the price of the raw material is high and the process operation cost is increased. Therefore, in order to develop low-cost electrocatalytic electrodes that replace these DSA electrodes, research on binary and ternary electrodes combining Sn, Sb, Zr, etc. with existing platinum group noble metals such as Ru and Ir is being conducted, but chlorine is still generated. There is no satisfactory performance in terms of efficiency. Since the reduction potential of the chlorine generation reaction is similar to the oxidation potential of water, increasing the selectivity of the chlorine generation reaction is essential for efficient process operation. Therefore, it is necessary to solve the problem that the chlorine oxidation efficiency is lowered as the electrode operates in water to promote the chlorine generation reaction and to reduce the noble metal content to secure the economic feasibility of the catalyst.

Korean Patent Publication No. 10-2013-0130504

In order to solve the above problems, an object of the present invention is to provide an electrode for ballast water electrolysis for sterilizing ballast water.

In order to achieve the above object, the present invention,

In the ballast water electrolysis electrode for sterilizing ballast water,

It includes at least one selected from metal mesh, metal foam, and metal plate, and Pt, Ru, and Ti catalyst layers are positioned on top of them,

The combined molar ratio of Pt:Ru in the catalyst layer is 1:9 to 9:1, the molar ratio of (Pt:Ru):Ti is 1:1 to 3,

A catalyst amount of Pt, Ru, and Ti loaded on the electrode for electrolysis is 0.5 to 5 mg/cm ² It provides an electrode for electrolysis of ballast water, characterized in that it comprises.

According to one embodiment of the present invention, the catalyst layer may be produced by firing at 400 to 900 °C.

According to another embodiment of the present invention, the catalyst layer may be manufactured by spray coating with an airbrush on at least one selected from a metal mesh, a metal foam, and a metal plate from which an oxide film is removed by acid treatment.

According to another embodiment of the present invention, at least one selected from the metal mesh, metal foam, and metal plate may use titanium, nickel, gold, copper, a nickel alloy, and stainless steel.

According to another embodiment of the present invention, a current density of 10 to 1000 mA/cm ² may be applied to the ballast water electrolysis electrode.

The electrode for ballast water electrolysis according to the present invention does not decrease chlorine oxidation efficiency even in competition with water oxidation and shows a selectivity of 98% or more for generation of active chlorine species. In addition, since the catalyst layer is prepared by reducing the content of precious metals, there is an advantage in securing economic feasibility of the catalyst.

1 shows an image of a two-electrode system according to an embodiment of the present invention.
2 shows a circuit model used in an experiment for measuring the charge transfer resistance of an electrode according to an embodiment of the present invention.
Figure 3 shows a graph of the concentration and current efficiency of the generated active chlorine species according to an embodiment of the present invention.
4 shows durability evaluation of an electrode according to an embodiment of the present invention.
5 shows a SEM image of an electrode surface according to an embodiment of the present invention.
6 shows an EDS analysis image of an electrode according to an embodiment of the present invention.
7 shows an XRD analysis image of an electrode according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

According to one aspect of the present invention, in the ballast water electrolysis electrode for sterilizing ballast water, it includes at least one selected from metal mesh, metal foam and metal plate, and Pt, Ru and Ti are on top of them. A catalyst layer is located, the combination molar ratio of Pt:Ru in the catalyst layer is 1:9 to 9:1, the molar ratio of (Pt:Ru):Ti is 1:1 to 3, Pt loaded on the electrode for electrolysis, A catalyst amount of Ru and Ti is 0.5 to 5 mg/cm ² It provides an electrode for electrolysis of ballast water, characterized in that it comprises.

The electrode for ballast water electrolysis of the present invention is manufactured by coating a Pt, Ru, and Ti catalyst layer on a metal mesh, metal foam and/or metal plate, and the detailed electrode manufacturing method is as follows. The metal mesh, metal foam and/or metal plate may be titanium, nickel, gold, copper, nickel alloy, or stainless steel, but is preferably titanium or stainless steel, most preferably titanium.

First, a mixture of Pt, Ru, and Ti metals is dissolved in a mixture of citric acid and ethylene glycol, and then fired for 30 minutes to 1 hour 30 minutes. Next, the obtained catalyst is put in isopropyl alcohol and ultrasonicated for 1 hour to 3 hours to make particles, and the oxide film is removed by treatment with strong acids such as hydrochloric acid, sulfuric acid, and nitric acid. Next, the Pt, Ru, and Ti catalysts from which the oxide film has been removed are coated on the titanium mesh, titanium foam, and/or titanium plate by a spray coating method using an airbrush.

The electrode of the present invention uses a Pt-Ru-Ti electrode as a working electrode, a Saturated Calomel Electrode as a reference electrode, and a counter electrode containing platinum or titanium. Electrolysis may be performed with an electrode system, or electrolysis may be performed with a two-electrode system using a Pt-Ru-Ti electrode as an anode and platinum or titanium as a cathode.

The efficiency of the chlorine oxidation reaction of the electrode manufactured by the above manufacturing method is measured by applying a current density of 10 to 1000 mA / cm ² to the electrode to measure the generation rate of active chlorine species, preferably 60 to 1000 mA / cm ² , more preferably is 80 to 1000 mA/cm ² , more preferably 80 to 800 mA/cm ² , and the efficiency of generating active chlorine species may be affected by the molar ratio of Pt and Ru, the catalyst amount, the firing temperature, and the presence or absence of Ti mixing. The molar ratio of Pt and Ru in the Pt-Ru-Ti catalyst layer may be 1:9 to 9:1, preferably 2:8 to 8:2. In the firing condition of 500 ° C, the efficiency is the best at a molar ratio of 8: 2, but excellent efficiency can be achieved with electrodes under other molar ratio conditions through a change in firing temperature, and the molar ratio of the electrode is selected in consideration of both efficiency and noble metal content. A catalyst having a molar ratio of Pt and Ru of 0:10 to 1:9 or 9:1 has a low active chlorine species generation rate, so the electrode cannot function properly.

After Ti mixing, the molar ratio of (Pt:Ru):Ti may be 3:7 to 7:3, but preferably the molar ratio of (Pt:Ru):Ti is 1:1 to 3. When the Ti content is increased, the noble metal content can be reduced, so that the economic feasibility of the electrode can be secured, and the function of the electrode can be stably maintained. The mixing of Ti stably maintains the function of the electrode with the active chlorine species production efficiency of 92 to 100% of the Pt-Ru-Ti electrode regardless of the firing temperature, and preferably the molar ratio of (Pt:Ru):Ti When 1: 1 to 3, it has a selectivity of 98 to 100% for the generation of active chlorine species.

In addition, when the molar ratio of (Pt:Ru):Ti after Ti mixing is 1:1 to 3, the charge transfer resistance It has the lowest electrochemically active area and the largest, the charge transfer resistance (R _ct ) of the electrode of the present invention is 30 to 40, and the electrochemical surface area is 5 to 7 mF/cm ² . At this time, the firing temperature is 450 to 550 ° C, most preferably 500 ° C.

The amounts of Pt, Ru, and Ti catalysts loaded on the electrode for electrolysis are 0.5 to 5 mg/cm ² , preferably 0.8 to 4 mg/cm ² . When the catalyst amount is less than 0.5 mg/cm ² , the rate of generation of active chlorine species of the electrode is significantly reduced, so that it cannot function as an electrode for ballast water electrolysis. When the catalyst amount is 5 mg/cm ² or more, the catalyst amount is 0.5 to 5 mg/cm The production rate of active chlorine species does not significantly increase compared to the case of using ² , and rather, the cost of electrode manufacturing increases.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. On the other hand, the drawings and detailed descriptions of configurations and their actions and effects, which can be easily known by those skilled in the art, are simplified or omitted, and will be described in detail focusing on parts related to the present invention.

<Example>

Example 1 - electrode fabrication

(1) Fabrication of Pt-Ru electrode

Pt and Ru were dissolved in a mixed solution of citric acid and ethylene glycol at a molar ratio of 0:10 to 9:1, and then calcined for 1 hour. At this time, the obtained catalyst was put in isopropyl alcohol, ultrasonicated for 2 hours to make particles, and then spray-coated using an airbrush on a titanium mesh from which oxide film was removed by acid treatment. At this time, in order to evaluate the durability of the electrode, some electrodes were heat treated at 300 ^*** C for 6 hours after spray coating separately. Then, the coated electrode was dried to complete the fabrication.

(2) Fabrication of Pt-Ru-Ti electrode

The ratio of Pt-Ru-Ti was 0.6:2.4:7 (mol%), and after dissolving in a mixture of citric acid and ethylene glycol, it was calcined for 1 hour. At this time, the obtained catalyst was put in isopropyl alcohol, ultrasonicated for 2 hours to form particles, and then coated with an airbrush on a titanium mesh from which an oxide film was removed by acid treatment. Then, the coated electrode was dried to complete the fabrication.

Example 2 - Performance analysis of the electrode

In order to observe chlorine oxidation of the electrode prepared in Example 1, an electrolysis experiment was conducted with a two-electrode system in 0.137 M, 0.5 M NaCl aqueous solution and artificial seawater. A Pt-Ru or Pt-Ru-Ti electrode was used as an anode and platinum or titanium was used as a cathode (see FIG. 1). As an electrode performance analysis experiment, the active chlorine species production efficiency and potential, electrochemical active area and charge transfer resistance according to the Pt-Ru combination ratio, firing temperature, and catalyst amount were measured. The current density applied to the electrode is 80 mA/cm ² , and the performance analysis method is as follows:

(1) Generation of active chlorine species

An experimental device was constructed with a two-electrode system, and electrolysis experiments were conducted in 0.137 M, 0.5 M, and 0.941 M NaCl aqueous solutions or artificial seawater. Hach is a method of calculating the concentration by extracting a certain amount of sample from the electrolyte according to time during the electrolysis experiment and measuring the absorbance of color development generated by the reaction between active chlorine species and DPD reagent (N,N-diethyl-p-phenylenediamine). method, the amount of active chlorine species generated during the reaction was measured and the Faradaic efficiency was calculated. When calculating the efficiency, it is calculated by multiplying by 2 because 2 electrons are required to generate active chlorine species:

[Equation 1]

Faradaic Efficiency (%)=

Q is the amount of charge (C) flowing during the electrochemical reaction, F is the Faraday constant (96485 C/mol), and n is the number of moles (mol) of the active chlorine species produced.

(2) Measurement of the electrochemically active area of the electrode

The activity of the fabricated electrode was confirmed by calculating ECSA (ElectroChemical Surface Area) through cyclic voltamogramm (CV). CV is 0.85-0.95 V vs. 0.5 M NaCl. The SCE range was measured from 20 to 100 mV/s.

(3) Measurement of charge transfer resistance of electrodes

Resistance during the electrochemical reaction was measured using electrochemical impedance spectroscopy (EIS). It was measured and calculated at 10 mV intervals at 0.01 ~ 50000 Hz (1.1 V vs. SCE) in 0.5 M NaCl. The circuit model used is shown in FIG. 2 .

Example 3 - Evaluation of electrode durability

A voltage measurement experiment was conducted for 500 hours in 0.941 M NaCl by applying a current density of 800 mA/cm ² to the electrode under Pt:Ru:Ti=0.6:2.4:7 conditions.

Example 4 - Evaluation of physical properties of electrode

(1) SEM analysis

For SEM (Scanning Electron Microscope, Scanning Electron Microscope) analysis, an image of the electrode surface was taken by applying an accelerating voltage of 5.0 kV using a Su-8230 (Hitachi) equipment.

(2) EDS analysis

Element mapping was performed using OXFORD's Ultim Extreme equipment attached to the SEM.

(3) XRD analysis

It was observed by applying Cu-Kα radiation (40 kV, 30 mA) with a wavelength of 1.5406 Å using Panalytical's EMPYREAN equipment.

<Results and evaluation>

Active chlorine species production efficiency according to the molar ratio of Pt-Ru

0.137 M NaCl 0.5 M NaCl Pt:Ru molar ratio Active chlorine species generation efficiency Pt:Ru molar ratio Active chlorine species generation efficiency 0:10 32.34% 0:10 54.84% 1:9 39.37% 2:8 47.80% 2:8 67.49% 3:7 49.21% 4:6 54.83% 4:6 71.71% 5:5 59.06% 6:4 64.7% 6:4 80.15% 7:3 54.84% 8:2 71.71% 8:2 90% 9:1 36.56% 9:1 81.55%

Table 1 shows the active chlorine species production efficiency of the prepared electrode according to the molar ratio of Pt and Ru at a firing temperature of 400 °C. Referring to Table 1, it was confirmed that the ratio of Pt-Ru with the highest production efficiency for active chlorine species was 8:2, and the ratio showing the lowest potential when the same current density was applied was 2:8.

Active chlorine species production efficiency according to firing temperature

0.137 M NaCl 0.5 M NaCl Pt:Ru
mole ratio firing temperature
(℃) Active chlorine species generation efficiency Pt:Ru
mole ratio firing temperature
(℃) Active chlorine species generation efficiency 8:2 400 80.15% 8:2 400 90% 500 100% 500 100% 600 80.15% 600 91.4% 2:8 400 46.40% 2:8 400 67.49% 500 67.49% 500 84.37% 600 77.33% 600 95.62% 700 78.74% 700 92.80% 800 91.40% 800 95.62% 900 75.93% 900 90%

Table 2 shows the efficiency and potential of active chlorine species according to the firing temperature. Referring to Table 2, the molar ratio of Pt:Ru was fixed at 8:2 or 2:8, and the efficiency of generating active chlorine species was measured in the temperature range of 400 to 900 °C. When the molar ratio was 8:2, the firing temperature was 500 °C. It was confirmed that the generation efficiency of active chlorine species was 100% regardless of the molarity of the NaCl solution. In addition, when the molar ratio was 2:8, the 0.137 M NaCl aqueous solution showed the highest active chlorine species generation efficiency at 800 ° C and 91.40%, and the 0.5 M NaCl aqueous solution showed the highest activity at 600 ° C and 95.62%, respectively. It was confirmed that the chlorine species production efficiency was shown.

Active chlorine species generation efficiency according to catalyst amount

Pt:Ru=8:2 Pt:Ru=2:8 electrolyte catalytic amount
(mg/cm ² ) Active chlorine species generation efficiency electrolyte catalytic amount
(mg/cm ² ) Active chlorine species generation efficiency 0.137M
NaCl 3.33 100% 0.137M
NaCl 3.33 91.40% 2.50 100% 2.50 90% 1.67 100% 1.67 70.30% 0.83 100% 0.83 66.09% 0.5M
NaCl 3.33 100% 0.5M
NaCl 3.33 95.62% 0.83 97.02% 0.83 100%

Table 3 shows the active chlorine species generation efficiency and potential according to the amount of catalyst in the state where the molar ratio of Pt-Ru and the firing temperature are fixed. Referring to Table 3, when the molar ratio of Pt-Ru is 8:2, the 0.137 M NaCl aqueous solution showed 100% active chlorine species generation efficiency regardless of the catalyst amount, and at 3.33 mg/cm ² in the 0.5 M NaCl aqueous solution. It was confirmed that the generation efficiency of active chlorine species was 100%. In addition, when the molar ratio of Pt-Ru is 2:8, in 0.137 M NaCl aqueous solution, as the amount of catalyst added increases, the active chlorine species generation efficiency increases, and it is the highest at 3.33 mg/cm ² at 91.40%, whereas in 0.5 M NaCl aqueous solution Rather, it was confirmed that the generation efficiency of active chlorine species was 100% when the catalyst amount was reduced to 0.83 mg/cm ² .

Observation of electrode performance according to Ti ratio after Ti mixing

0.137 M NaCl 0.5 M NaCl (Pt:Ru):Ti molar ratio Active chlorine species generation efficiency (Pt:Ru):Ti molar ratio Active chlorine species generation efficiency 1:9 83% 1:9 85.77% 2:8 85.77% 2:8 91.397% 3:7 98.43% 3:7 100%

Table 4 shows electrode performance evaluation according to Ti ratio after Ti mixing. Referring to Table 4, when the molar ratio of (Pt:Ru):Ti was 3:7, it was confirmed that the efficiency of generating active chlorine species was 98% or more and had the best performance.

Observation of electrode performance after Ti mixing

0.137 M NaCl 0.5 M NaCl Pt:Ru:Ti molar ratio firing temperature
(℃) Active chlorine species generation efficiency Pt:Ru:Ti molar ratio firing temperature
(℃) Active chlorine species generation efficiency 0.6:2.4:7 400 92.80% 0.6:2.4:7 400 94.21% 500 98.43% 500 100% 600 99.83% 600 100% 700 97.02% 700 94.21% 800 94.21% 800 92.80% 900 98.43% 900 100%

Table 5 shows the performance evaluation of the ternary electrode after Ti mixing. Referring to Table 5, it can be seen that (Pt:Ru):Ti was combined at a molar ratio of 3:7 and the ratio of Pt:Ru combined with Ti was set at 2:8, and the conventional Pt:Ru = 2: Compared to the electrode manufactured with a molar ratio of 8, it was confirmed that it showed excellent performance regardless of the firing temperature.

Observation of electrode characteristics after Ti mixing

Pt:Ru:Ti molar ratio Firing temperature (℃) EIS ECSA R _{s Rct Cdl} (mF/cm ² ) 0.6:2.4:7 400 6.358 69.63 0.81 500 6.182 35.71 5.745 600 5.884 95.92 4.385 700 6.450 259.6 0.63 800 4.771 333.2 1.875 900 3.719 427.9 0.685

Table 6 shows the observed characteristics of the ternary electrode after Ti mixing. Referring to Table 6, the lowest charge transfer resistance and the largest electrochemical active area were observed at the firing temperature of 500 ° C, which showed the best performance in the active chlorine species experiment, and it can be seen that the firing temperature of 500 ° C is an excellent manufacturing condition. there was.

Observation of electrode performance according to catalyst amount after Ti mixing

0.137 M NaCl 0.5 M NaCl Catalytic amount (mg/cm ² ) Active chlorine species generation efficiency Catalytic amount (mg/cm ² ) Active chlorine species generation efficiency 3.33 98.43% 3.33 100% 0.83 100% 0.83 100%

Table 7 shows the performance evaluation of the three-way electrode according to the catalyst amount after Ti mixing. As a result of observing the electrode performance according to the catalyst amount by fixing the molar ratio of Pt:Ru:Ti = 0.6:2.4:7 and the firing temperature at 500 °C, it was confirmed that the electrode exhibited excellent performance regardless of the catalyst amount. Figure 3 shows a graph of the concentration and current efficiency of the generated active chlorine species according to an embodiment of the present invention. Referring to FIG. 3, the current efficiency is 95% or more, which means that the Pt-Ru-Ti catalyst shows a selectivity of 95% or more for the generation of active chlorine species.

Efficiency of production of active chlorine species in artificial seawater

Pt:Ru = 8:2 (500 ℃) Pt:Ru = 2:8 (600 ℃) Pt:Ru:Ti = 0.6:2.4:7 (500 °C) catalytic amount
(mg/cm ² ) Active chlorine species generation efficiency catalytic amount
(mg/cm ² ) Active chlorine species generation efficiency catalytic amount
(mg/cm ² ) Active chlorine species generation efficiency 3.33 90.00% 3.33 95.62% 3.33 91.40% 0.83 90.00% 0.83 92.80% 0.83 91.40%

Table 8 shows the efficiency of producing active chlorine species in artificial seawater of the manufactured electrode. Referring to Table 8, it was confirmed that the efficiency was slightly decreased compared to the NaCl solution condition of a similar concentration due to the influence of various ions contained in the artificial seawater, but it showed excellent performance of 90% or more even in artificial seawater.

Durability evaluation of Pt-Ru-Ti electrode

4 shows durability evaluation of an electrode according to an embodiment of the present invention. Referring to FIG. 4, it was observed that the electrodes that were not heat-treated were damaged and the voltage greatly increased after 14 hours, but the heat-treated electrodes did not increase the voltage for 500 hours, confirming that they had strong durability. .

In addition, before and after the durability evaluation experiment, an active chlorine species generation experiment was performed while applying a current density of 80 mA/cm ² in a 0.941 M NaCl aqueous solution, and the results were compared to evaluate whether or not the electrode was damaged during the durability evaluation. Table 9 is a result of comparing the efficiency of generating active chlorine species of the electrode before and after the durability evaluation experiment. After the durability evaluation, it was confirmed that the efficiency of the electrode decreased slightly, but it was confirmed that the efficiency was still high.

0.941 M NaCl Pt-Ru-Ti Active chlorine species generation efficiency as-synthesized 97% used 90%

Evaluation of physical properties of Pt-Ru-Ti electrode

5 shows a SEM image of an electrode surface according to an embodiment of the present invention. Referring to FIG. 5 , it was confirmed that the Pt-Ru-Ti catalyst was formed in the form of nanoparticles on the titanium substrate. 6 shows an EDS analysis image of an electrode according to an embodiment of the present invention. Referring to FIG. 6, it can be seen that each element of the Pt-Ru-Ti catalyst on the titanium substrate is not unevenly distributed and is evenly distributed over the entire electrode. 7 shows an XRD analysis image of an electrode according to an embodiment of the present invention. Referring to FIG. 7, peaks of RuO ₂ , TiO ₂ and Pt appeared, whereby it can be seen that Ru and Ti exist in oxide form and Pt exist in metal form, and RuO ₂ , TiO ₂ and metal Pt are present. It can be seen that they are mixed.

The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the scope of the invention which follows may be better understood. Those skilled in the art to which the present invention pertains will understand that the present invention can be embodied in other specific forms without changing its technical spirit or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. The scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the claims and equivalent concepts should be construed as being included in the scope of the present invention.

Claims (5)

In the ballast water electrolysis electrode for sterilizing ballast water,
It includes at least one selected from metal mesh, metal foam, and metal plate, and Pt, Ru, and Ti catalyst layers are positioned on top of them,
The combined molar ratio of Pt:Ru in the catalyst layer is 1:9 to 9:1, the molar ratio of (Pt:Ru):Ti is 1:1 to 3,
Electrode for ballast water electrolysis, characterized in that the catalyst amount of Pt, Ru and Ti loaded on the electrode for electrolysis comprises 0.5 to 5 mg/cm ² .
According to claim 1,
The catalyst layer is an electrode for ballast water electrolysis, characterized in that produced by firing at 400 to 900 ℃.
According to claim 1,
The catalyst layer is an electrode for ballast water electrolysis, characterized in that produced by spray coating with an airbrush on at least one selected from a metal mesh, metal foam and metal plate from which oxide film is removed by acid treatment.
According to claim 1,
Electrode for ballast water electrolysis, characterized in that at least one selected from the metal mesh, metal foam and metal plate is titanium, nickel, gold, copper, nickel alloy and stainless steel.
According to claim 1,
An electrode for electrolysis of ballast water, characterized in that a current density of 10 to 1000 mA/cm ² is applied to the electrode for electrolysis of ballast water.

Images