Solid-liquid two-phase partitioning bioreactors (TPPBs) operated with waste polymers. Case study: 2,4-dichlorophenol biodegradation with used automobile tires as the partitioning phase

Used automobile tire pieces were tested for their suitability as the sequestering phase in a twophase partitioning bioreactor to treat 2,4-dichlorophenol (DCP). Abiotic sorption tests and equilibrium partitioning tests confirmed that tire ''crumble'' possesses very favourable properties for this application with DCP diffusivity (4.8 9 10-8 cm2/s) and partition coefficient (31) values comparable to those of commercially available polymers. Biodegradation tests further validated the effectiveness of using waste tires to detoxify a DCP solution, and allow for enhanced biodegradation compared to conventional singlephase operation. These results establish the potential of using a low-cost waste material to assist in the bioremediation of a toxic aqueous contaminant.