When a metal surface experiences stress—such as a dent—oxidation can occur, leading to rust formation, otherwise known as corrosion. This is a common problem for industrial equipment, especially cooling towers and other water treatment apparatuses. Rusted equipment can no longer operate optimally, leading to slower production and safety risks. The guide below discusses how corrosion inhibitors work and what types are available to you. 

What Is a Corrosion Inhibitor?

Corrosion is a chemical reaction, in which an anode—a type of electrode—lose electrons to a cathode—another type of electrode—in a two-step process involving an anodic reaction and a cathodic reaction. A corrosion inhibitor decreases the potential for the metal to react, thereby acting as a protective barrier against rust. 

Types of Corrosion Inhibitors 

When choosing a corrosion inhibitor, you’ll have four main options:

• Anodic Inhibitors: These react with oxygen to form a protective film on a metal surface that’s less susceptible to corrosion. Specifically, they interfere with anodic reactions. Common examples include chromate, orthophosphate, and nitrite. 
• Cathodic Inhibitors: This type of inhibitor works in two different ways depending on the form. Some types, such as arsenic and selenium ions, prevent corrosion by slowing cathodic reactions. Others, which are known as oxygen scavengers and include sulfite and bisulfite ions, combine with oxygen to form sulfate, which reduces the rate of corrosion.
• Mixed Inhibitors: These inhibitors form a protective film on a metal surface to prevent both cathodic and anodic reactions.
• Volatile Corrosion Inhibitors: Metal surfaces in closed environments, such as those found in condenser tubes or those being shipped in airtight packages, face an increased risk of corrosion due to humidity exposure—as does metal equipment used in water treatment. Volatile corrosion inhibitors form a protective film on these metals to keep them safe. They have a higher vapor pressure at normal temperatures than other inhibitors. 

To protect your equipment from corrosion, turn to Western Environmental Management Corp. Established over 35 years ago, the Carlsbad, NM-based company will help you find the ideal corrosion inhibitors to protect your investments. Serving facilities throughout New Mexico and El Paso, TX, the team also offers a variety of water treatment products and services, such as water softeners, water boilers, and water analysis. Learn more about the company online. Call (575) 885-5709 to discuss your needs with a team member.