The main objective of this study was to investigate the performance of a cyclic rotating-bed biological reactor (CRBR) in comparison to a sequencing continuous-inflow reactor (SCR) for the biodegradation and mineralization of catechol. Results showed that catechol degradation and mineralization in the SCR at the organic loading of 7.82 kg COD/m(3) d and the hydraulic retention time (HRT) of 9 h were 28.2% and 10.3%, respectively. Under similar operating conditions to SCR, steady-state performance of CRBR with polyurethane foam (PUF) media for degradation and mineralization of catechol achieved was 98.7% and 97.9%, respectively. In comparison, the CRBR with 2H media attained average steady-state catechol degradation and mineralization of 89.1% and 83.6%, respectively, under similar conditions. Accordingly, the CRBR with PUF media presents a promising process for efficiently treating wastewater containing high concentrations of toxic, inhibitory and resistant compounds at a relatively short HRT. (C) 2013 Elsevier Ltd. All rights reserved.