# Effect of degassing on particle size

• kasse
In summary, degassing is the process of removing dissolved gases from a liquid or solid material, and it can affect particle size by decreasing it and resulting in a more homogeneous and finer particle size distribution. The most common methods for degassing in particle size analysis include vacuum degassing, sonication, and centrifugation. Degassing can improve the accuracy of particle size measurements by removing gas bubbles that can interfere with the process. However, it can be time-consuming and may require specialized equipment, and it can also potentially affect the properties of the particles themselves, so careful consideration is necessary before choosing to degas a sample.
kasse
The specific surface area of polluting dust particles has been determined by gas adsorption:

Treatment__________________Asp (m2g-1)
4 h under vacuum at 200 °C_____5.61
8 h under vacuum at 25 °C_____2.81

Assume that they are monodisperse spheres of density r = 2.2 g/cm3. Calculate the radius of the particles.
Propose an explanation for the effect of degassing on particle size.

The radia are 243 nm and 485 nm, but what is the explanation?

Daga
You know the rules. What thoughts do you have on the question?

When particles adsorb gas particles, they grow larger?

Last edited:

## 1. How does degassing affect particle size?

Degassing is the process of removing dissolved gases from a liquid or solid material. In the context of particle size, degassing can cause a decrease in particle size by reducing the presence of gas bubbles that can act as nucleation sites for the formation of larger particles. This can result in a more homogeneous and finer particle size distribution.

## 2. What methods are commonly used for degassing in particle size analysis?

The most common methods for degassing in particle size analysis include vacuum degassing, sonication, and centrifugation. Vacuum degassing involves subjecting the sample to reduced pressure to remove dissolved gases. Sonication uses high-frequency sound waves to agitate the sample and release trapped gases. Centrifugation involves spinning the sample at high speeds to force gases out of the solution.

## 3. Can degassing improve the accuracy of particle size measurements?

Yes, degassing can improve the accuracy of particle size measurements. This is because the presence of gas bubbles can interfere with the measurement process and lead to inaccurate results. By removing these gas bubbles, degassing can provide more reliable and precise particle size measurements.

## 4. Are there any drawbacks to degassing in particle size analysis?

One potential drawback of degassing in particle size analysis is that it can be time-consuming and may require specialized equipment. Additionally, some samples may be difficult to degas completely, which can affect the accuracy of the results. It is important to carefully consider the sample and the purpose of the analysis before deciding to degas.

## 5. Can degassing affect the properties of the particles themselves?

Yes, degassing can affect the properties of particles, particularly in materials that are highly sensitive to changes in gas concentration. For example, in some materials, degassing can result in changes in surface chemistry or morphology of the particles. Therefore, it is important to carefully consider the potential effects of degassing on the sample before conducting any analysis.

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