Advanced Oxidation Technology Classification of Advanced Oxidation Technologies

Relying on the Institute of Ceramic Chemistry of Harbin Institute of Technology, Harbin Specification Technology Co., Ltd. is a high-tech enterprise engaged in metal surface research research, micro-arc oxidation power supply manufacturing, and production process research and development. The company's main technical personnel have nearly 20 years of experience in micro-arc oxidation, and took the lead in the research of micro-arc oxidation technology in China, first published the research on micro-arc oxidation treatment on the surface of titanium alloy in China, and obtained 11 authorized patents in the preparation process of related coatings and the development of power equipment. It has been supported by 9 scientific research projects, including the 863 Program, the National Natural Science Program, the National Natural Science Program, the Pre-research Program, and the Military Products Package.

It has laid a theoretical and technical foundation for the research and development of this technology, and has formed a team of ...

Due to the mild reaction conditions and strong oxidation ability, photochemical oxidation has developed rapidly in recent years, but due to the limitation of reaction conditions, a variety of aromatic organic intermediates will be produced when photochemical treatment of organic matter, resulting in incomplete degradation of organic matter, which has become a problem that needs to be overcome by photochemical oxidation. Photochemical oxidation methods include photoexcitation oxidation (e.g., 03 UV) and photocatalytic oxidation (e.g., Ti02 uv).

The photo-excited oxidation method mainly uses 03, H and air as oxidants, and produces ·OH under the action of light radiation; The photocatalytic oxidation method is to add a certain amount of semiconductor catalyst to the reaction solution to produce ·OH under the irradiation of ultraviolet light, both of which are treated with organic pollutants through the strong oxidation of ·OH. Ozone oxidation is mainly achieved through direct reaction and indirect reaction. Among them, direct reaction refers to the direct reaction between ozone and organic matter, which has strong selectivity, generally attacks organic matter with double bonds, and is usually more effective for unsaturated aliphatic hydrocarbons and aromatic hydrocarbons; Indirect reaction refers to the decomposition of ozone to produce ·OH, through which it oxidizes with organic matter, which is not selective.

Although the ozone oxidation method has a strong ability to decolorize and remove organic pollutants, the operation cost of this method is high, the oxidation of organic matter is selective, the pollutants cannot be completely mineralized in low doses and short time, and the intermediate products generated by decomposition will prevent the oxidation process of ozone. It can be seen that ozone oxidation still has great limitations in the treatment of landfill leachate. The Fenton-like method is to use the basic principle of the Fenton method to introduce UV, 03 and photoelectric effects into the reaction system, therefore, in a broad sense, all other technologies for the treatment of organic matter by generating hydroxyl radicals by H202 can be called the Fenton-like method.

As an improvement of the Fenton oxidation method, the Fenton-like method has greater development potential.

Advanced oxidation technology, also known as deep oxidation technology, is based on the use of electricity, light irradiation, catalysts, and sometimes combined with oxidants to produce highly active free radicals (such as Ho) in the reaction, and then through the addition of free radicals and organic compounds, substitution, electron transfer, bond breaking, etc., so that the macromolecules in the water body are oxidized and degraded into low-toxic or non-toxic small molecule substances, and even directly degraded into CO2 and H2O, which is close to complete mineralization, electrochemical oxidation, wet oxidation, supercritical water oxidation and photocatalytic oxidation.

Advanced oxidation technology, also known as deep oxidation technology, is characterized by the generation of hydroxyl radicals (·OH) with strong oxidation ability under the reaction conditions of high temperature and high pressure, electricity, sound, light irradiation, catalyst, etc., so that macromolecules refractory to degradation of organic matter are oxidized into small molecule substances with low toxicity or non-toxicity. Common ones are photooxidation, catalytic wet oxidation, ozone oxidation, electrooxidation, and fenton oxidation.

Advanced chemical oxidation technology is a new technology method that comes into being on the basis of the reform of the classical chemical oxidation method in the traditional water treatment technology

The non-advanced oxidation process is as follows:

There are many kinds of advanced oxidation processes, and the advanced oxidation method uses hydroxyl radicals as the main oxidant to realize the degradation process of organic matter. Using a large number of active hydroxyl radicals generated in physical and chemical processes such as light, sound and magnetism, because of its high redox electricity (E0=+), organic pollutants in water can be directly oxidized into non-toxic small molecule substances and even CO2 and H2O.

The advanced oxidation method has the following characteristics: First, it has high efficiency. A large number of hydroxyl radicals are produced during the oxidation process, and their oxidation capacity is second only to that of fluorine (.

In addition, hydroxyl radicals are intermediate products that can induce the continuation of subsequent reactions. Secondly, there is no secondary pollution. Hydroxyl radicals directly react with free radicals in water and oxidize to CO2 and H2O, which will not produce secondary pollution; Again, it has a wide range of applications.

The hydroxyl radical has a strong electronic affinity, which can directly drag out the H in the saturated hydrocarbon, so that the organic matter itself can be oxidized and the degradation of organic matter can be realized. Finally, it is controllable. AOPS is actually a physico-chemical treatment process, and its process is easy to control.

Photocatalytic oxidation of active blue fuel wastewater was carried out through a self-made TiO2 GEO2 composite membrane photocatalytic oxidation reactor. The reaction conditions were 400 H2O2 and 120 min of light, and the removal rate of COD was high, and the treatment effect was good.

It is not difficult to find that photocatalytic application technology has developed rapidly due to its advantages of low energy consumption, convenient operation, no secondary pollution, and mild reaction conditions, and is widely used in the treatment of refractory substances, such as printing and dyeing wastewater, inorganic polluted wastewater, bacterial-containing wastewater, and oily wastewater. However, it also has its own limiting factors, such as the catalyst is easy to deactivate and difficult to deactivate, and the light energy utilization rate is low.

Advanced oxidation technology, also known as deep oxidation technology, is characterized by the generation of hydroxyl radicals (·OH) with strong oxidation ability, and oxidizes macromolecules refractory organic matter into low-toxic or non-toxic small molecule substances under high temperature and high pressure, electrical, acoustic, photoirradiation, catalyst and other reaction conditions. According to the different ways of generating free radicals and reaction conditions, they can be divided into photochemical oxidation, catalytic wet oxidation, sonochemical oxidation, ozone oxidation, electrochemical oxidation, fenton oxidation, etc.

With the rapid development of China's national economy, the high concentration of organic wastewater poses a threat to China's precious water resources. However, the use of existing biological treatment methods, it is difficult to treat substances with poor biodegradability and relative molecular mass from thousands to tens of thousands, while advanced oxidation process (AOPS) can directly mineralize them or improve the biodegradability of pollutants through oxidation, and also has great advantages in the treatment of trace harmful chemicals such as environmental hormones, which can completely mineralize or decompose most organic matter, and has a good application prospect.