For a large number of manufacturing processes the chemicals produced will contain moisture (water) , oxygen , nitrogen and other gases. This will affect the purity of the chemicals which are being produced.

Molecular Sieves are sorts of desiccants that have varying properties from those of silica gel. These materials are artificially created of exceptionally permeable translucent substance made of metal-aluminosilicates. The appearance is of minuscule obscure pinkish globules made of a few inside holes interconnected by window openings of exact distances across.