Biotrickling filters work by passing a stream of contaminated air
through a chemically inert packing material, over which an aqueous
phase is continuously trickled. Microorganisms grow as biofilms on
the surface of the packing material by using pollutants transferred
from the gas to the biofilm phase as energy and/or carbon sources.
Removal of high loads of H2S in biotrickling filters under aerobic
and anoxic conditions has been reported as a viable and economical
technique with several advantages in comparison with classical
physical–chemical processes [5,6]. H