The hygroscopic effect of the desiccant for laboratory equipment and glass instruments
The desiccant maintains the space desiccant by absorbing the moisture in the air. Usually, the action environment of the desiccant is not liquid water, and the target object is not selected correctly. A good desiccant will use waterproof and breathable packaging materials, because the desiccant absorbs water vapor in the air rather than liquid water. If the desiccant is directly thrown into the water, under the action of liquid water, the water should be an impermeable waterproof and breathable packaging material, otherwise the water can enter and reversely seep out (similar to a sponge), thus losing the desiccant itself. Moisture absorption and anti-reverse osmosis effect. After the desiccant absorbs moisture, the moisture should be absorbed in the desiccant, and there should be no moisture on the surface. If you take out the desiccant soaked in water, it will definitely drip. This also shows that the test method of directly throwing the desiccant into the water and soaking it is wrong. Desiccant absorbs moisture in the air to make the environment relatively dry, and its main ability is to absorb moisture in the air rather than liquid moisture.
It is not a sponge. Superabsorbent resins are used to absorb liquid water, so it is a wrong practice to directly pour water on the desiccant to test the moisture absorption effect. The temperature and humidity of the desiccant test environment are unstable. The ambient temperature and humidity have a significant impact on the moisture absorption capacity of the desiccant. The open test environment can only be used to make a year-on-year qualitative comparison of different desiccant products.
The direct test method is to weigh. The desiccants produced by our company are calcium chloride desiccants that can absorb moisture effectively, and their moisture absorption effect can reach more than 200%. So we only need to weigh it before absorbing the moisture, and let it absorb the moisture before weighing. This method is simple and easy to identify the moisture absorption rate.