Simultaneous 4-chlorophenol and nitrogen removal in moving bed sequencing batch reactors packed with polyurethane foam cubes of various sizes

► Removal of 4-CP and TN in MBSBR with polyurethane (PU) foam cubes of various sizes. ► High 4-CP and TN removal in MBSBR with 27-mL PU cubes at high 4-CP concentration. ► Biomass in inner layers of PU foam cubes was shielded from the 4-CP inhibition. ► Optimum packing volumes of 20% of 27-mL PU cubes in high 4-CP removal.