ADSORPTION AND KINETICS STUDY FOR THE REMOVAL OF PENDIMETHALIN FROM AQUEOUS SOLUTION USING ACTIVATED CARBON PREPARED FROM AGRICULTURAL WASTE

The wreak havoc pose by herbicide on the environment and the ecosystem has become an issue of interest to the environmentalist over the past years. Up till date, adsorption methods has been demonstrated to be an excellent technique to remediate herbicides by comparison with other traditional methods due to its high efficiency, low operating and maintenance cost, simple design, insensitivity for toxic substances, suitable for most contaminated waters and the complete removal of contaminants even from the dilute solutions. This paper is aim at investigating and establishing the adsorption efficiency of activated Bambara groundnut shells in the removal of pendimethalin (PE) herbicide from aqueous solution under different experimental conditions. The pore volume analysis of the adsorbent demonstrated good quality of the activated carbon. It also had low moisture content and bulky density respectively. The activated Bambara groundnut shell (ACBGNS) was also characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) analysis methods. The Effect of initial concentration (10 to 60mg/l), solution pH (3 to 8), adsorbent dosage (0.2 to 1.2g) and contact time (20 to 120) were optimized and reported. Adsorption capacity qe (mg/g) of PE onto ACBGNS was found to be 14.93mg/g. A comparison of kinetic models applied to the adsorption of PE on the ACBGNS was evaluated for the pseudo first-order, the pseudo second-order, Elovich and intra-particle diffusion kinetic models, respectively. Results showed that the pseudo second-order kinetic model was found to relatively correlate the experimental data well when compared to other models