With the development of industry,water sources are increasingly polluted by various organic compounds.The traditional method of chlorination disinfection in water supply systems has been found to form harmful substances to the human body?Therefore,researching new alternative sterilization methods has increasingly become a hot topic and important development direction both domestically and internationally?Most of the existing commercialized electric disinfection water processors produce disinfectants such as chlorine dioxide and sodium hypochlorite through electrolysis after adding electrolytes such as sodium chloride?Xinxiang Future Water Chemistry Co.,Ltd.has developed a new type of electrolytic sterilizer using its own insoluble titanium anode,titanium electrode,and platinum plated titanium electrode materials,which can achieve the effect of sterilization and algae removal without affecting water quality.
At present,water treatment sterilization commonly adopts the oxidation disinfection method of adding chlorine or chloride to water.But it was found that adding chlorine disinfection can lead to the production of"carcinogenic,teratogenic,and mutagenic"substances in drinking water.The UV,ozone,ultrasound,magnetization,electrostatic and other treatment methods developed in recent years have not been widely applied due to complex equipment,low water flow rate,or high treatment costs.The electrolysis method is popular as a sterilization water treatment technology with good sterilization effect,strong usability,and no secondary pollution.
Electrolytic sterilization can be divided into two types:indirect sterilization and direct sterilization:
1、Indirect sterilization:using electrolysis to produce substances such as ClO-,HclO3,H2O2,O2-,·OH-to kill microorganisms.The existing commercialized disinfection processors mostly produce disinfectants such as chlorine dioxide and sodium hypochlorite after adding electrolytes such as sodium chloride.
2、Direct sterilization:Direct sterilization is the use of electrolytic electrodes to directly act on microorganisms,causing them to die.
Mechanism of electrolytic sterilization and disinfection:
Electrolysis of chlorine containing water produces ClO-and a small amount of higher valence chlorate.The reaction on the electrode is as follows:anode:2Cl-2e→Cl2,Cl2+H2O→HClO+H++Cl-,OH-ions diffuse into the liquid layer around the anode and react with hypochlorous acid to form ClO-,?And further react to generate chloric acid:12ClO-+6H2O-12e→4HClO3+8HCl+3O2?The HClO and HClO3 produced are both strong oxidants with strong bactericidal effects on microorganisms.
When electrolyzing water without chloride ions,there is also a good bactericidal effect when the raw water does not contain Cl-,indicating that HOCl is removed during electrolysis?Other oxidizing substances,after analysis,exhibit the following reactions on the anode side:?①The H2O?→H+?+?OH-?②20H-?-?2e?→[O]+?H2O?→H2O2?③4OH-?－?4e?→2H2O?+?02?④[O]+?O2?→O3
Therefore,strong oxidizing disinfectants such as H2O2,O3,[O]are produced,which make the treated water electrolyzed and have a strong bactericidal effect.????⑶Electrolysis directly acts on bacterial cell bodies,damaging a certain bacterial organ and causing bacterial death.
The modern view on the bactericidal effect of chlorine is that it mainly works through HClO.When HClO molecules reach the interior of bacteria,they can oxidize and destroy the bacterial enzyme system?As a result,bacteria die and the final products of oxidation are CO2 and H2O.Therefore,even with continuous use of chlorine,it will not cause bacteria to develop drug resistance.
