Utilization of an Agro Waste, Groundnut Shell Ash, for Removal of 2,4-Dichlorophenoxyacetic Acid

The work highlights efficient utilization of groundnut shell ash (GSA) for various applications. The production groundnut seeds average about 45,654 metric tons across the globe. Those seeds are used as a food material and for extraction of edible oil. The shells of groundnut seeds are waste, having a high calorific value so its potential is tapped in industries and boilers. Subsequently upon the utilization of biomass, the ash, which is produced, is of ample quantity needs to be addressed properly for its chemical, physical properties and its potential application. GSA is a rich source of micronutrients and improves yield, and is spread on agriculture lands as a soil additive. Groundnut shells are a rich source of fuel. From literature study it is evident that the GSA is used for various applications like stabilization of black cotton soil, adsorption, as a concrete admixture. For the first time, GSA has been evaluated as an adsorbent for 2,4-D removal from aqueous solutions and as a soil additive. GSA was characterized extensively by X-ray fluorescence, BET surface area and SEM image. Results of XRF analysis showed that GSA can be used as a rich source of micronutrients such as MgO, Al₂O₃, SiO₂, K₂O and CaO. 2,4-Dichlorophenoxyacetic acid (2,4-D), a commonly used pesticide, was chosen as a representative adsorbate for studying the effects of various parameters in batch adsorption. BET surface area is found to be 22 m²/gm. SEM image shows a very rough and irregular structure of the GSA surface. Batch adsorption experiment studied to find the effect of adsorbent dose, initial 2,4-D concentration, and equilibrium time. Based on the batch results dosages of GSA/hectare have been recommended for different crops to serve the dual purpose i.e., as an adsorbent and a soil additive.