Modelling of biological Cr(VI) removal in draw-fill reactors using microorganisms in suspended and attached growth systems

► Cr(VI) bio-reduction was examined in suspended and attached growth reactors. ► Enrichment culture was comprised mainly of Enterobacteriacea and Pichiaceae members. ► Tsao & Hanson's and Aiba & Shoda's models were used to describe Cr(VI) bioreduction. ► Attached growth reactors presented reduced inhibitory effect of Cr(VI).