Electrochemical methods used for the treatment of difficult to degrade organic matter has a very good effect, it can make non-biochemical degradation of organic matter into biochemical degradation of organic matter. The reaction rate of electrochemical conversion of organic matter is generally slow, so it is commonly used to increase the overpotential of the electrode, increase the surface area of the electrode, choose excellent electrode materials, and improve the electrode structure and other methods to improve. In electrochemical reactions, the surface area of the electrode is accompanied by a non-homogeneous catalytic reaction with charge movement, which is similar to chemical catalysis. In a certain electrolyte, under the same overpotential, the rate of electrode reaction and the type of reaction varies depending on the electrode substrate material, which is collectively called electrocatalysis in electrochemistry. In the electrocatalytic reaction, as an electrocatalyst, different electrode materials can make the electrochemical reaction rate change by orders of magnitude. Therefore, the selection of appropriate electrode materials is an effective way to improve the efficiency of electrochemical catalytic reactions.
In the field of water treatment, especially in the electrolysis of water, such as the generation of acid, alkali ionized water, the process of water, there are a variety of strong oxidizing substances, such as: O3, H2O2, HCLO, etc., and the anode is often changed, so it is necessary to use special functional electrodes. After years of research, our company has developed a long-life electrode ---- titanium coated electrode suitable for the field of water treatment. This kind of electrode is coated with platinum noble metal oxides with high electrocatalytic performance, strong antioxidant performance and good electrical conductivity on pure titanium substrate, which is an insoluble anode. The properties of this anode are:
1. Titanium is characterized by light specific gravity, good strength, corrosion resistance and good performance, especially the resistance to wet chlorine is incomparable to other metal materials. For example, when there is a trace amount of chlorine ions in the electrolysis of water, the Stainless Steel pole plate will pitting corrosion will occur very quickly, shortening the life of the electrode, while titanium does not have these problems. 2. In the coating due to the addition of a variety of platinum noble metals, so the current efficiency, good electrical conductivity, good electrocatalytic properties, strong oxidation resistance, long working life, energy saving.
3. It has very good reverse pole performance.
Titanium anode is the key component in water electrolysis machine, and the good or bad metal electrode directly affects the quality of the whole water machine. How to choose the electrode should be reasonably selected according to the different nature of work, in the field of water treatment metal electrode must have the following basic requirements:
1. Good electrical conductivity.
2. Strong corrosion resistance.
3. Good mechanical strength and processing performance.
4. Long working life.
5. Good electrocatalytic properties and so on.
Multi-component electrodes are also an important research aspect in electrochemical reactions.The preparation of Ti/Sn02-Sb203 “Mn02/Pb02-Mn02 anode can be used as an example of multi-component electrode design. The main reason for the failure of titanium anodes is the diffusion of new ecological oxygen from the oxygen precipitation reaction to the electrode surface, which generates a non-conductive Ti02 film on the titanium surface. In order to activate the anode, a PbO2-Mn02 active layer is added to the electrode surface; and in order to reduce the diffusion of new ecological oxygen onto the titanium surface, a SnOz-Sb203-Mn02 intermediate layer is added between the titanium anode substrate and the active layer. In the treatment of phenol-containing wastewater, the anode has high electrocatalytic activity and electrochemical stability.
