BACKGROUNDNitrobenzene (NB) is a persistent environmental pollutant difficult to degrade. The aim of this study was to accelerate the reduction of NB by immobilization of nanoscale zero-valent iron (NZVI) on an organobentonite (CTMA-Bent). RESULTSBatch experiments indicated that NB was almost completely reduced by the immobilized iron sample (NZVI/CTMA-Bent), with aniline as the dominant reduction product. While only 60% of NB was reduced by the bare NZVI, and aniline accounted for only half of the NB reduced. Kinetic studies confirmed that the reaction of NB with NZVI was accelerated through CTMA-Bent adsorption. XPS investigations suggested that the improved recycling of the NZVI/CTMA-Bent composite is related to less ferric (hydr)oxides formed during the reaction. CONCLUSIONImmobilization of NZVI on the organobentonite CTMA-Bent proved to be an effective method for quick and complete conversion of NB to biodegradable aniline. This novel method to remove recalcitrant organic pollutants may promote the industrial application of NZVI technique in environmental remediation. (c) 2013 Society of Chemical Industry