How does a defoaming agent work?

Defoaming agent is a common chemical substance whose main function is to remove bubbles on the surface of liquids. In many industrial and production processes, the presence of air bubbles can adversely affect product quality and performance. Therefore, defoaming agents are widely used in many fields, such as food, chemical industry, pharmaceuticals, textiles, papermaking, etc.

The function of defoaming agents is to remove bubbles by changing the surface tension of liquids. Liquid surface tension refers to the intermolecular interaction force on the liquid surface, which causes the liquid surface to exhibit a state of tension and form a film that hinders the release of bubbles. The molecular structure of the defoaming agent contains hydrophilic and hydrophobic groups, which can form a molecular film on the surface of the liquid, change the surface tension of the liquid, and cause the bubbles to burst and disappear.

The hydrophilic groups of defoaming agents are usually hydroxyl groups, alcohol groups, acid groups, etc. They can form hydrogen bonds with water molecules and adsorb on the liquid surface. Hydrophobic groups are usually alkyl groups, aryl groups, etc., which can interact with gas molecules to burst bubbles. The molecular structure of the defoaming agent contains both hydrophilic and hydrophobic groups, allowing them to form a molecular film on the liquid surface and adsorb on the bubble surface, causing the bubbles to burst and disappear.

The selection and use of defoaming agents need to consider many factors, such as liquid properties, bubble size, usage environment, etc. Different defoaming agents are suitable for different liquids and bubbles. Choosing the appropriate defoaming agent can improve the defoaming effect and reduce the usage and cost of defoaming agents. There are many ways to use defoaming agents, such as adding them directly to the liquid, spraying on the surface of the liquid, passing through a gas disperser, etc. The specific selection method needs to be based on the actual situation.

In addition to defoaming agents, there are some other defoaming methods, such as mechanical defoaming, vacuum defoaming, ultrasonic defoaming, etc. Each of these methods has advantages and disadvantages, and the appropriate method needs to be selected based on the actual situation. Mechanical defoaming requires equipment investment and the cost is high; vacuum defoaming requires equipment and operating technology; ultrasonic defoaming requires an ultrasonic generator and control system. In contrast, defoaming agents are a simple, convenient and economical method of defoaming and are used in various fields.

In short, defoaming agent is an important chemical substance. Its function is to remove bubbles by changing the surface tension of liquid. The selection and use of defoaming agents need to consider many factors, such as liquid properties, bubble size, usage environment, etc. Defoaming agent is a simple, convenient and economical defoaming method, which is used in various fields.