BACKGROUNDRecent studies have characterized the most effective absorbent polymers for the removal of volatile hydrophobic pollutants from air. This study evaluates the performance of a laboratory scale -pinene-degrading biotrickling filter (BTF) packed with lava rock. A second solid phase, Hytrel((R)) G3548L (5%, v/v), was added in order to check its effect on the performance of the system during long-term operation. RESULTSThe biodegradation profile was similar in both bioreactor configurations, with or without solid polymers, reaching a maximum elimination capacity (ECmax) around 25.6gm(-3)h(-1) when an inlet loading rate of 57.2gm(-3)h(-1) was applied. Tracer studies were carried out in order to determine the effect of the liquid and gas velocities, and to analyze the gas distribution with the different packing materials. CONCLUSIONSDeviation from ideal flow caused by channelling of the fluid was observed from tracer studies. No better performance was observed under steady-state conditions in the presence of polymeric Hytrel material. Further considerations are needed for the selection of an appropriate absorbent polymer for -pinene removal. (c) 2015 Society of Chemical Industry