Stabilization of Fe-Pd bimetallic nanoparticles with sodium carboxymethyl cellulose for catalytic reduction of para-nitrochlorobenzene in water

The reactivity of Fe-Pd bimetallic nanoparticles with sodium carboxymethyl cellulose (CMC) as a stabilizer toward para-nitrochlorobenzene (p-NCB) was investigated in this study. The CMC-stabilized Fe-Pd nanoparticles exhibited markedly greater reactivity than non-stabilized iron counterparts when used for the degradation of p-NCB in aqueous solution. Batch kinetic tests demonstrated that the pseudo-first order rate constant with the stabilized bimetallic particles was four times greater than that for the non-stabilized iron. At a dose of 0.2 gL(-1), the Fe-Pd bimetallic nanoparticles were able to remove 100% of p-NCB (C-0=50 mg L-1) within 40 min, small amounts of p-chloroaniline (p-CAN) as an intermediate were detected in the final stage of degradation, with no other products except aniline (AN) and inorganic chloride (Cl-). Insignificant reactions were observed with the unpalladized iron, suggesting that the presence of Pd could significantly enhance the reductive dechlorination. The degradation efficiency of p-NCB increased with the increasing addition of Pd bulk loading, Fe-Pd mass concentration and temperature, with the decrease of pH values and humic acid (HA) dosage. (C) 2010 Elsevier B.V. All rights reserved.