【Daily Question】12.8 Cathodic protection and anodic protection (2 wealth points for a reply + additional 3–8 wealth points for a correct answer)
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This post was last edited by lzy4225925 on 2015-12-9 08:18. The Mechanical Section has introduced the \"Question of the Day\" feature, which aims to foster an active atmosphere for technical discussions and guide the direction of such exchanges. It also provides users with financial rewards, helping them experience various cool features. Question: Briefly describe the differences between cathodic protection and anodic protection? 1) Metals can all be cathodically protected in electrolytes ； Anodic protection is only applicable when the metal can be anodically passivated in that dielectric. 2) During cathodic protection, a deviation in potential only reduces the efficiency of protection and does not accelerate corrosion ； In anodic protection, if the potential deviates from the passivation potential range, corrosion will be accelerated. 3) For strongly oxidizing media such as sulfuric acid and *ao acid, cathodic protection is less effective than anodic protection. 4) During cathodic protection, if the potential becomes too negative, the equipment may suffer from hydrogen embrittlement. During anodic protection, the equipment acts as the anode, and hydrogen embrittlement only occurs on the auxiliary cathode. 5) The auxiliary electrode for cathodic protection is an anode that is meant to dissolve, so its use in highly corrosive media is limited. The auxiliary electrode for anodic protection is the cathode, which is itself protected to a certain extent. Please note: We will close this thread after 24 hours, and at that time we will announce the best reply (the best assistance), as well as the answer and explanation. Charisma Reward: If you post a topic in this section within two days to provide a detailed explanation or discussion of the knowledge points related to this question, please reply or leave a comment in this post to let us know, and we will have a moderator award you charisma points. It is not allowed to simply copy and paste; original content is preferred, with at least some organization by the user along with personal insights. After registration, we will rank participants based on the content of their posts: the last-place participant will receive +1 charm, the second-to-last +2 charm, and so on, with the highest score earning +5 charm. Other details: Recruitment for moderators & technicians in the [Mechanical Area] – applications and referrals are welcome. 【Valid indefinitely】【If you’re interested, come ahead!】 】(Click to enter) 【Mechanical Zone】Comprehensive guide to preventing equipment freezing over winter in the Mechanical Zone 【Mechanical Zone】Call for collection of essential knowledge 【Seeking manufacturer sponsors】(Ongoing campaign) 【Rewards for recommending valuable content; the “Active Users and Weekly Stars” competition in the Mechanical Zone has begun】
Cathodic protection is a type of electrochemical protection technique. Its principle involves applying an external current to the surface of the metal structure that is subject to corrosion; the structure under protection becomes the cathode, which prevents or reduces the electron migration that leads to metal corrosion. There are two types of cathodic protection technologies: sacrificial anode cathodic protection and forced current (external current) cathodic protection. Sacrificial anode cathodic protection is a technique in which a metal or alloy with a more negative potential than the metal to be protected is electrically connected to it; the current generated by the continuous corrosion and dissolution of this metal with the more negative potential is used to protect the other metals. Forced current cathodic protection technology involves inserting a DC power supply into the circuit; with the help of an auxiliary anode, direct current is directed to the metal to be protected, thereby turning that metal into a cathode and providing protection.
Cathodic protection involves connecting a metal to the cathode of a power source; since the cathode continuously supplies electrons, it prevents the metal atoms from losing electrons, thereby protecting the metal. Anodic protection involves placing a more reactive metal A in contact with metal B. Because active A has a stronger reactivity, AB forms a galvanic cell; during the reaction, it is A that loses electrons, thereby protecting B.
Briefly describe the differences between cathodic protection and anodic protection? The difference between cathodic protection and anodic protection: Both cathodic protection and anodic protection belong to the category of electrochemical protection methods. However, they each have distinct characteristics, as follows: ① In the case of cathodic protection, a deviation in potential only results in a reduced level of protection; it does not accelerate the rate of corrosion. In the case of anodic protection, if the potential moves away from the passivation region, it will lead to increased corrosion ； ②In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is employed. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. ③During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is very dangerous for pressurized systems. ④The auxiliary electrode for cathodic protection is the anode, which needs to dissolve. Chemical media are highly corrosive, and it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive environments. As a result, the application of cathodic protection in certain chemical media is limited. However, the auxiliary electrode for anodic protection is the cathode, which itself also receives a certain degree of protection
1. During cathodic protection, a deviation in potential only leads to a reduction in the effectiveness of protection; it does not accelerate the rate of corrosion. When anodic protection fails, if the potential deviates from the passivation region, corrosion will increase； 2. In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is used in 1. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. 3. During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is extremely dangerous for pressurized systems. 4. The auxiliary electrode for cathodic protection is the anode, which is meant to dissolve. Chemical media are highly corrosive, and it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive environments; as a result, the use of cathodic protection in certain chemical media is limited. However, the auxiliary electrode of anodic protection is the cathode, which is also protected to a certain extent.
Briefly describe the differences between cathodic protection and anodic protection? ①During cathodic protection, a deviation in potential only leads to a reduction in the effectiveness of protection; it does not accelerate the rate of corrosion. After the deterioration of anodic protection, if the potential deviates from the passivation region, corrosion will increase ； ②In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is employed. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. ③During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is extremely dangerous for pressurized systems. ④The auxiliary electrode for cathodic protection is the anode, which needs to dissolve. Chemical media are highly corrosive, and it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive environments; as a result, the use of cathodic protection in certain chemical media is limited. However, the auxiliary electrode of anodic protection is the cathode, which is also protected to a certain extent.
Both cathodic protection and anodic protection fall under the category of electrochemical protection, but they have different characteristics. As follows: ① In the case of cathodic protection, a deviation in potential only results in a reduced level of protection; it does not accelerate the rate of corrosion. In contrast, with anodic protection, if the potential deviates from the passivation region, it leads to increased corrosion. ②In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is employed. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. ③During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is extremely dangerous for pressurized systems. ④The auxiliary electrode for cathodic protection is the anode, which needs to dissolve. Chemical media are highly corrosive, and it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive environments; as a result, the use of cathodic protection in certain chemical media is limited. However, the auxiliary electrode of anodic protection is the cathode, which is also protected to a certain extent.
In the oxidation process of metals, they lose electrons and turn into metal cations. If we want to prevent them from losing electrons, then: 1. Cathodic protection involves connecting the metal to the cathode side of the power supply; since the cathode continuously supplies electrons, this prevents the metal atoms from losing electrons, thus protecting the metal. 2. Anodic protection involves placing a metal with higher reactivity, A, in contact with the metal B in question. Because A has greater reactivity, a galvanic cell is formed, and during the reaction it is A that loses electrons, thereby protecting B
1. Cathodic protection involves connecting the metal to the cathode of a power source; since the cathode continuously supplies electrons, it prevents the metal atoms from losing electrons, thereby protecting the metal. 2. Anodic protection involves placing a metal with higher reactivity, A, in contact with metal B. Because A has greater reactivity, a galvanic cell is formed, and during the reaction it is A that loses electrons, thus protecting metal B
The differences between cathodic protection and anodic protection: Both cathodic protection and anodic protection belong to the category of electrochemical protection methods. However, they each have distinct characteristics, as follows: ① In the case of cathodic protection, a deviation in potential only results in a reduced level of protection; it does not accelerate the rate of corrosion. On the other hand, in anodic protection, if the potential deviates from the passivation region, it will lead to increased corrosion； ②In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is employed. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. ③During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is very dangerous for pressurized systems. ④The auxiliary electrode for cathodic protection is the anode, which needs to dissolve. The corrosivity of chemical media is very high; however, it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive media. As a result, the application of cathodic protection in certain chemical media is limited. However, the auxiliary electrode of anodic protection is the cathode, which is also protected to a certain extent.
Both cathodic protection and anodic protection belong to electrochemical protection methods, but they each have distinct characteristics. As follows: ① In the case of cathodic protection, a deviation in potential only leads to a reduction in the effectiveness of protection; it does not accelerate the rate of corrosion. In the case of anodic protection, if the potential deviates from the passivation region, it will result in increased corrosion； ②In strongly oxidizing media, such as sulfuric acid and *ao acid, a very large current is required when cathodic protection is employed. However, strongly oxidizing media are more conducive to the formation of a passivation film, thereby enabling anodic protection. For example, the anodic protection of sulfur trioxide generators. ③During cathodic protection, if the potential becomes too negative, hydrogen embrittlement can occur in the equipment, which is extremely dangerous for pressurized systems. ④The auxiliary electrode for cathodic protection is the anode, which needs to dissolve. Chemical media are highly corrosive, and it is not easy to find a material that can resist corrosion under the action of anodic current in such highly corrosive environments; as a result, the use of cathodic protection in certain chemical media is limited. However, the auxiliary electrode of anodic protection is the cathode, which is also protected to a certain extent.