Fenton like oxidative degradation of toxic water pollutants by iron nanoparticles synthesized via facile green route using waste iron rust as the iron precursor

Abstract

Corrosion of iron by oxidation is a global problem that affects the economy and gives rise to environmental pollution. Iron rust is oxide or hydroxide of iron, it can be used as a secondary iron source which will lead to its management as well as reduce the pressure on primary iron sources. In the present study, waste iron rust was used as the precursor of iron for the synthesis of iron nanoparticles via the green route using extract of dried Jatropha leaf. Synthesized nanoparticles were characterized using different instrumental techniques. Synthesized iron nanoparticles bear an extremely large specific surface area of 190.2 m2/g. The catalytic potential of synthesized nanoparticles was tested for the degradation of toxic organic pollutants phenol and p-nitrophenol (PNP) in an aqueous solution. Both the pollutants were removed rapidly in the initial 30 minutes of the reaction time. Optimization of the removal process was done by varying different variables. Maximum removal of phenol (~98%) and PNP (~95%) was achieved at 0.1 g/L concentration of nanoparticles. The degradation reaction rate was determined by pseudo-first-order and pseudo-second-order kinetics and the data was found to be followed best by the pseudo-first-order kinetics.