Air filters of many types and materials of construction have been designed, manufactured, and applied to meet a wide variety of industrial and commercial requirements types). Commercially available filters are divided into three distinct categories based on how they operate to remove suspended particulate matter from the air passing through..

http://www.engineersedge.com/filtration/air_filter_types.htm

Acticvated Carbon, Air Fitlers, Bag Filters, Corrosion considerations, HEPA Filter design application and construction, High Temperature Filter, Liquid filtering, Membrane Filters, Stainless Steel Filters...

http://www.engineersedge.com/filtration/filtration_table_content.htm