Overview

The Fenton reaction system can effectively oxidize and remove refractory organic matter that cannot be removed by traditional wastewater treatment technologies. The essence is that H2O2 generates highly reactive hydroxyl radicals (•OH) under the catalysis of Fe2+. • OH can interact with most organic substances to degrade them. At the same time, the Fenton reaction system can also improve the biodegradability of sewage through oxidation. The role of Fenton reagent in water treatment mainly includes the oxidation and coagulation of organic matter:

Fenton oxidation: The reason why Fenton reagent has a very high oxidation ability is that under the catalysis of Fe2+ ions, the decomposition activation energy of H2O2 is low (34.9KJ/mol), which can decompose to produce hydroxyl radical OH-. Compared with some other oxidants, the hydroxyl radical OH- has a higher oxidation electrode potential, so it has a strong oxidation performance. Influencing factors of Fenton’s reagent to treat refractory organic wastewater According to the mechanism of the above-mentioned Fenton’s reagent reaction, OH- is an effective factor for oxidizing organic matter, and [Fe2+], [H2O2], [OH] determine the output of OH-, Thus determines the degree of reaction with organic matter.

Electrochemical action: When iron-carbon contacts with electrolyte solution, a primary battery with iron-carbon as two poles is formed. Among them, the carbon pole has a high potential and is the cathode, while the iron pole has a low potential and is the anode. In wastewater treatment, electrochemical corrosion is free to proceed. Since the continuous generation of Fe2+ can effectively overcome the polarization of the anode, thereby promoting the electrochemical reaction of the whole system, a large amount of Fe enters the solution and has a high electrochemical reduction activity. The new ecology produced by the electrode reaction can undergo redox reactions with many components in the solution. At the same time, iron is an active metal, and its reducing ability can reduce some components to a reduced state.

Filtration adsorption and co-precipitation: The internal electrolysis reaction column composed of iron filings and carbon particles has a good filtration effect, and the colloid formed by the reaction can not only strengthen the filtration adsorption effect, but also produce new colloidal particles. Its central gel core is an insoluble particle with a large specific surface area formed by the polymerization of many Fe(OH). It is easy to carry a large amount of harmful substances, and can co-precipitate with various metals to achieve the purpose of removal.

Features:

①Environmentally friendly: unlike other chemicals after treatment, such as bleach (sodium hypochlorite), it is easy to produce toxic substances such as chlorinated organics, which will cause harm to the environment.

②Small footprint: The oxidation rate of organic matter is quite fast, and the required residence time is short, about 0.5-3 hours, unlike general biological treatment, which takes about 12-24 hours. Due to the short time, the volume of the reaction tank is small Need too big, can save space.

③ Large operating flexibility: the operating conditions can be changed according to the quality of the influent water, and the processing capacity can be increased. However, general biological treatment is difficult to operate flexibly. For higher pollution, it is only necessary to increase the dosage of ferrous iron and H2O2 and to control the appropriate pH.

④ Low initial setup cost: Compared with general biological treatment systems, it only needs 1/3~1/4 of its investment cost.

⑤Strong oxidation ability: The generated hydroxyl radical (OH) has a strong oxidation ability. It can handle a variety of toxic substances, such as vinyl chloride, BTEX, chlorobenzene, 1,4Dioxane, phenol, polychlorinated biphenyls, TCE, DCE, PCE, etc., and EDTA and ketones MTBE, MEK, etc. are also effective.