Titanium Anode for Chlor-Alkali Industry_Ruthenium Iridium Titanium Anode

The chemical industry that produces chlorine gas and caustic soda by electrolyzing salt (NaCl) water melt is called chlor-alkali industry. The products of the chlor-alkali industry—chlorine, hydrogen and caustic soda are basic chemical raw materials and are widely used in chemical, petrochemical, metallurgy, light industry, textile, and civil sectors.

The technical key to the production of chlorine and caustic soda by electrolysis of brine solution is to separate the cathode and anode products in the electrolytic cell. Otherwise, various side reactions and secondary reactions will occur, which will greatly reduce the yield and product quality, and may explode. According to the method of product separation, the chlor-alkali industry has formed two different production processes, namely diaphragm electrolysis and mercury electrolysis.

1. Diaphragm electrolysis

Diaphragm electrolysis separates the anode and cathode regions with a porous membrane, avoiding the mixing of the bipolar products. Diaphragm electrolytic cells began to use carbon anodes, which have high cell pressure and large losses. After the advent of metal anodes, they were applied to the chlor-alkali industry, making breakthroughs in the chlor-alkali industry. The metal anode coatings can be RuTi, RuSnTi, RuIrTi, etc.

2. Ion membrane electrolysis

The ionic membrane electrolysis method not only has the advantages of high product quality and low energy consumption, but also can eliminate the pollution and environmental pollution caused by the use of asbestos and mercury in the diaphragm method. Ion membrane electrolyzers all use metal anodes, and most of the cathodes use active cathodes that reduce the overpotential of hydrogen evolution.

Compared with the graphite electrode, the diaphragm method produces caustic soda, and the working voltage of the graphite anode is 8A/DM2, which can be doubled to 17A/DM2. In this way, the product can be doubled under the same electrolysis environment, and the quality of the produced product is high and the purity of chlorine gas is high.

Electrochemical performance of ruthenium-titanium coated metal anodes in chlor-alkali industrial electrolyzers

1. The discharge overpotential of chlorine on the ruthenium-titanium metal anode is significantly lower than that on the graphite anode.

2. The oxygen evolution potential of the ruthenium titanium coating is also low.

3. Strong corrosion resistance and long working life.