Filtra Catalysts and Chemicals Ltd. Offer Candle Filters. Filtra Catalysts and Chemicals Ltd. Is an ISO 9001:2000 accredited company. The Candle Filters have a sturdy metallic casing to meet the requirement of installation, cleaning and reuse. The cast ceramic fibre provides the efficient filtering media. It has applications in Nitric Acid plants for filtration of air and ammonia mixture, Instrument Air Filters, Process gas filters where filtration of upto 1 micron size particles is desired, Filtration of liquids requiring very fine particles to be removed etc.