A desiccant is a substance that removes some of the moisture from a moist material. For example, calcium sulfate, calcium chloride, etc., are dried by combining with water to form a hydrate.
1. Acidic desiccant, such as concentrated sulfuric acid, phosphorus pentoxide, etc.
(1), an acid desiccant for drying acidic or neutral gases, wherein concentrated sulfuric acid cannot dry hydrogen sulfide, hydrogen bromide, hydrogen iodide, strong reducing acid gas, pentoxide Phosphorus cannot dry ammonia.
2, a neutral desiccant, such as anhydrous calcium chloride.
(2), neutral desiccant, anhydrous calcium chloride, general gas can be dried, but anhydrous calcium chloride can not dry ammonia and ethanol.
3, alkaline desiccant, such as sodium hydroxide solid, quicklime and so on.
(3), alkaline desiccant, soda lime (a mixture of CaO and NaOH, KOH), quicklime (CaO), NaOH solids, used to dry neutral or alkaline gases.
Among these desiccants, there is a special desiccant which is [lime]
Because calcium contains calcium oxide, calcium oxide A chemical reaction will produce calcium hydroxide after encountering water.
In fact, most desiccants are, not like lime, so terrible.
There are many types of desiccants, but most of them are alkaline substances and are highly corrosive.
For example, lime calcium hydroxide is a desiccant with strong alkalinity.