Desiccator

Desiccators are small enclosures which are used in laboratories to store the chemical substances which would otherwise react with the moisture or humidity present in the air. A typical desiccator is made of heavy glass (usually rugged soda lime glass) and has two compartments in it. The lower one has a desiccant, which withdraws the moisture out of the air and keeps the desiccator dry. These desiccants could be anhydrous sodium chloride pellets or silica gel. The upper compartment keeps the substance which needs to be protected. A lid at the top closes the desiccator. Some enclosures use an additional vacuum stopcock for further evacuation of air. These are called vacuum desiccator. A manual of specifications with regards to handling and maintenance comes along. Things to take care of • Desiccators should be tested before using • It may take some time after adding the desiccants for the adsorption of moisture • A vacuum grease or petroleum jelly is used on the lid to ensure air-tight sealing • A highly hygroscopic substance may not be suited for this type of desiccator since the lid open time to time • Not suitable for large storage. A cabinet desiccator must be used for large storage. • A dehumidifier zone may be set up around the desiccator for maximum efficiency