Adsorption of p-Phenylenediamine onto Activated Carbon Prepared from Jatropha curcas and Terminalia catappa Seed Coats

This research work is concerned with the applicability of sodium hydroxide-activated carbon prepared from Jatropha curcas seed coats and Terminalia catappa seed coats in the removal of p-phenylenediamine (PPD), a component of hair dye industrial effluent. The surface characteristics of the prepared activated carbons were examined using Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis and Fourier Transform Infrared Spectroscopy (FTIR). The influence of various factors such as initial concentration, pH, contact time, adsorbent dose and temperature were studied and the p-phenylenediamine adsorption capacity was found to be 32.4 mg/g and 45.5 mg/g for Jatropha activated carbon (JAC) and Terminalia activated carbon (TAC), respectively. The experimental data were analysed using Langmuir, Freundlich and Dubinin-Radushkevich isotherms. The data could be fitted successfully for both systems by the Langmuir and Freundlich isotherms. The data show also that the sorption process is exothermic and that it follows pseudo second order kinetics.