Removal of organic pollutants in Fenton process using nano zero valent iron (nZVI) has certain drawbacks such as formation of sludge, difficulty in recovery/reuse of nZVI and high concentration of Fe2+/Fe3+ ions into the final effluent. The challenge is to stabilize the nZVI and control leaching of Fe2+/Fe3+ ions without compromising the primary objective of removal of organic pollutants. This study demonstrates low temperature synthesis of carboxymethyl cellulose (CMC) stabilized nZVI hybrid (CMC-Fe2+(-nZVI)). In this hybrid, Fe2+ ion present on the surface of nZVI is sandwiched between CMC and nZVI. At low temperature (similar to 10 degrees C), CMC provides excellent control over the size (<7 nm) of CMC-Fe2+(-nZVI). The new orientation of peaks in the UV-Vis absorbance spectra of CMC, Fe2+-CMC and CMC-Fe2+(-nZVI) further supported the formation of CMC-Fe2+(-nZVI) hybrid. Similarly, ATR-FTIR spectra of CMC and CMC-Fe2+(-nZVI) showed significant shift in the functional groups of -C=O and OH and confirmed their chelation with Fe2+ central ion. Redox properties of CMC-Fe2+(-nZVI) when evaluated with cyclic voltammetry (CV) showed distinct oxidation and reduction peaks due to the formation of Fe2+ and Fe3+ ions. Furthermore, the redox properties and performance of CMC-Fe2+ (-nZVI) catalyst was assessed in Fenton process using phenol as a representative pollutant. Cyclic stability of CMC-Fe2+(-nZVI) was performed at the scan rate of 60 mV/s and only less than 1% reduction in stability was observed at the end of 100 cycles. The Fe2+(-nZVI) particle was effectively stabilized by CMC and only trace amount of Fe2+ was observed in solution at the end of the reaction. In addition, reuse of CMC-Fe2+(-nZVI) led to complete phenol removal and this sustained for more than 50 cycles. (C) 2015 Elsevier B.V. All rights reserved.