One of the most important indicators for determining the quality of silica gel desiccant is the amount of adsorption. There are often several misunderstandings in determining the amount of adsorption:
1. Take a small amount of silica gel desiccant into the water and observe the intensity of its water explosion: the explosion is fast and the explosion effect is strong. The product is considered to have low water content and good adsorption capacity.
Misunderstanding: In fact, the water-explosion rate of silica gel desiccant has little to do with the water content and adsorption capacity of silica gel. It can't reflect the water absorption of desiccant very well, because "explosion" is only a moment, and the water absorption performance is continuous. The desiccant is not used to directly adsorb liquid water, but is used for adsorption. Gaseous water molecules in the air. Actually, there are some products on the market that are deliberately produced by the manufacturers with a "explosive rate". The water content can only reach 15%, and the adsorption capacity is far lower than the 28% specified in the silica gel desiccant industry standard GB10455-89. -30% is completely unqualified.
2. Take a small amount of silica gel desiccant and seal it with a small amount of color-changing silica gel to observe the discoloration speed of the color-changing silica gel. The slow color-changing speed proves that the water content of the product is low.
Misunderstanding: This test method is more scientific, but only shows whether the water content of the silica gel desiccant tested exceeds the color change silica gel. In addition, the color-changing silica gel produced by the respective manufacturers may also cause discoloration of the color-changing silica gel due to the difference in the proportion of the added raw materials. Therefore, we cannot fully convince this test method.
3. Take a small amount of silica gel desiccant and place it on the outside for 2 days. Weigh it and calculate the difference between the two weighing results. If the difference is large, the product is considered to have a good adsorption amount.
Misunderstanding: The principle of this method is correct, but because the external environment is constantly changing, the results detected by this method are not completely convinced.
4, Take a small amount of silica gel desiccant in your hand and feel it is hot. If it is hot, it proves that its quality is good.
Misunderstanding: Silica gel desiccant will release a certain amount of heat when absorbing moisture, but it is completely incorrect because it is artificially felt.