Iron nanoparticles (FeNPs) were prepared from the green tea extracts at different temperatures through green synthesis procedure and characterized by various physicochemical techniques like UV-Visible spectroscopy, FTIR Spectroscopy, energy dispersive X-ray spectrometry (EDS), X-ray diffraction and high resolution tunneling microscopy (HRTEM) and the results confirmed the synthesis of polydisperse and stable FeNPs by the tea extracts. The catalytic activity of FeNPs was investigated using a common environmental pollutant BTB often used in textile industries for dyeing purposes. In these tests, catalytic degradation of BTB with FeNPs at a 10 μL or 30 μL concentration was done in the presence of 2% hydrogen peroxide. Results show no BTB degradation in the absence of the FeNPs. However, a 38% and 68% degradation of BTB was realized in the presence of 10μL and 30 μL FeNPs respectively indicating that the iron nanocatalysts were responsible for the dye degradation. The BTB degradation kinetics was found to follow pseudo-first order kinetics with rate constants at the two catalyst concentrations being 0.023 min-1 and 0.063 min-1 respectively.