What Are the Different Kinds of Metal Anodes?

Metal anode ^[1], also known as shape-stable anode, is a coating of a mixed crystal structure of a platinum group metal (such as ruthenium) oxide and a valve metal (such as titanium) on the substrate of metal titanium by thermal decomposition. . This coating is more resistant to reduction than the noble metal passivation film, has good catalytic activity, is convenient for chloride ion discharge (chlorine overpressure is lower than on graphite), and has sufficient mechanical strength and corrosion resistance. It is resistant to salt water and airflow. Impact and chlorine corrosion. The shapes are drawn titanium plate (for diaphragm electrolytic cell and ion membrane electrolytic cell) and spacer titanium bar (for mercury electric rod). The projected area of the pore opening can reach 50% to 60% of the total anode area, allowing the bubbles formed on the anode surface to escape quickly, reducing the bubble effect, improving the circulation of the electrolyte, and reducing the concentration polarization effect. More importantly, it is used in diaphragm electrolyzers. Due to the stable external dimensions of the metal anodes, the distance between the yin and yang poles is constant during the operation of the electrolyzer, so the voltage drop in the brine gap is greatly reduced, and it is not fixed by pouring lead, eliminating lead Danger of pollution. Used in mercury electrolyzers, because the anode does not have to be replaced often, reducing the chance of pollution caused by exposure to mercury. Generally in a diaphragm electrolytic cell, the service life is 7 ~ 8 years; in a mercury electrolytic cell, the current density varies. High current density (10-12 kA / m2) is about two years, and low current density (5 -6 kA / m2) at about four years. And after failure, the coating can be used again after renewed.

Metal anode

Right!

Metal anode ^[1]

Pinyin: jinshuyangji

English name: dimensional stable anode; DSA

(1) The tank voltage is low;

(2) High current efficiency;

(3) Low power consumption;

(4) Can be used at high current density;

(5) The product has high purity;

(6) Durable and long-term use of electrolytic cell;

(7) Small maintenance workload and expense paper;

(8) Eliminate lead damage and reduce mercury pollution;

(9) Constant electrode spacing, high purity of electrolytic substance

By Chen Kangning, Metal Anode, Shanghai: East China Normal University Press, July 1989,

ISBN: 9787561702901/7561702906

Book Introduction

Abstract: Since the introduction of metal anodes in the late 1960s, they have received great attention from the majority of electrochemical workers. In the electrolytic industry (such as chlor-alkali industry, chlorate industry, electroplating, metal protection, water treatment, seawater desalination, electrochemical synthesis, mud method) Smelting, etc.) are widely used. This book introduces in detail the manufacturing process, coating formula, electrochemical characteristics, old electrode repair and recoating, recycling and application examples of metal anodes, and the active coating from the theory of material structure, semiconductor, electrochemistry, electrocatalysis, etc. The electrical conduction mechanism and the reason of the coating deactivation are discussed and recognized.

Book Catalog

table of Contents

Chapter 1 A Brief History of the Development of Metal Anodes

First, the origin of the invention of the metal anode

Technical and economic effects of metal anodes

Chapter 2 Electrode Materials

First, the characteristics of electrode materials

Second, electrocatalysis

Chapter III Anode Process

First, the significance of studying the anode process

Second, the dissolution process of the anode

Third, the anode passivation phenomenon

Fourth, the passivation mechanism of the anode

Chapter 4 Preparation Process of Ruthenium-Titanium Coated Metal Anode

First, the preparation process

Second, the main equipment

Factors affecting the quality of ruthenium-titanium coated metal anodes

Chapter 5 Electrochemical Characteristics of Ruthenium-Titanium Coated Metal Anode

First, the electrochemical performance of ruthenium-titanium coating

Second, the conductive mechanism of ruthenium-titanium coating

3. Discharge mechanism of chloride ion on ruthenium-titanium coating

Reasons for the loss of activity of ruthenium-titanium coatings

Chapter 6 Improvement of Ruthenium-Ti Coating on Metal Anode

I. High oxygen super-coated metal anode with iridium interlayer

Second, tin-antimony interlayer ruthenium-coated metal anode

Three, palladium-containing high oxygen super-coated metal anode

Chapter VII Operation and Management of Metal Anode Electric Cells for Chlor-Alkali Production

I. Factors affecting current efficiency

Protective measures during parking

Third, economic current density

Modification of asbestos diaphragm

V. Establishing and improving the management of electric troughs

Chapter VIII Repair and Recoating of Ruthenium-Titanium Coated Metal Anode

I. Standard questions about repainting

Selection of electrode recoating repair methods

Third, the sulfuric acid electrolytic method to remove the old coating

Chapter IX Recovery of Ruthenium

First, the process of electrolytic nail recovery

Relevant chemical principles in the recycling process

Third, examples of recycling ruthenium

4. Main equipment and operation requirements in the process of recovering ruthenium

5. The quality of -RuCl3 · xH2O produced by recycling

Economic benefits

Chapter 10 Measurement of the Microscopic State of Metal Anodes

I. Measurement method for conductivity type of metal anode coating

Second, the measurement of the resistance of the metal anode active coating

Measurement of chlorine release potential of metal anode coating

Fourth, the measurement of the oxygen anode passivation life of the metal anode coating

Five, phase composition analysis of metal anode coating

Determination of surface area of metal anode coatings

Determination of nail content in metal anode coatings

Observation of surface morphology of metal anode coating

Chapter XI Other Types of Metal Anodes

Manganese dioxide coated metal anode

Second, lead anode

3. Cobalt spinel anode

Chapter 12 Application Examples of Metal Anode

I. Metal anodes for the chlor-alkali industry

Second, for the production of hypochlorite (bleach, disinfectant)

Third, for the production of perchlorate

Fourth, for electrodialysis desalination

V. Used for electrolytic treatment of wool spinning and dyeing wastewater

Six, for electrolytic organic synthesis

Seven, hydrometallurgy and electroplating

Chapter 13 Examples of Typical Coating Formulations

First, ruthenium-containing coating

Second, non-ruthenium coating

Third, non-precious metal coating

Chapter XIV Outlook

First, continuously improve the performance of ruthenium-coated metal anodes

Research on coatings to reduce metal nails

Development of new coatings for non-precious metal oxides

Fourth, attach importance to basic theoretical research

Appendix I Reference electrode

First, the main performance of the reference electrode

Second, calomel electrode

Third, mercury-mercury oxide electrode

4. Mercury-Mercury Sulfate Electrode

Appendix II Hydrogen reduction method to determine the percentage of nails in RuCl3 · xH2O

Appendix III Quality Inspection Standards for Ruthenium-Chin Metal Anode Coatings (Interim, 1978)

Appendix IV Application of Thiourea Spectrophotometric Determination of Ruthenium

Appendix V International Atomic Scale