Sunil K. Deokar

Rice Husk Ash for Fast Removal of 2,4-Dichlorophenoxyacetic Acid from Aqueous Solution

Rice husk ash (RHA) is a rich source of micronutrients and improves yield, and is spread on agriculture lands as a farming practice. For the first time, RHA has been evaluated as an adsorbent for pesticide removal from aqueous solutions. RHA was characterized extensively by X-ray fluorescence, Fourier transform infrared spectroscopy, BET surface area, CO2, H2O, N2 and SO2 (CHNS) analysis. 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. Compared with granulated activated carbon, RHA gave 10,000 times higher rate constant. Thus, RHA adsorbs 2,4-D instantly and stops its further transport through soil. On the basis of adsorption capacity, RHA dosage per hectare of land is recommended for different crops and fruits. Thus, RHA serves dual purposes: (a) as a source of micronutrients and (b) as an effective adsorbent for fast removal of pesticide, in addition to inhibiting groundwater leaching.

Use of Biomass Ashes in Agriculture with Reference to Farming Practices in Vidarbha, Maharashtra, India

As a regular farming practice in India, especially in Vidarbha, biomass ashes (BMAs) are spread on farmland. BMA forms a protective layer on the soil surface and acts as a barrier, thereby preventing direct contact between pesticides and soil. BMA acts: (i) as an adsorbent for removal of pesticides; (ii) as a soil additive and water enhancer, and (iii) as a micronutrient source for plants. In this study, paraquat, a representative chemical was selected to prove the hypothesis that BMAs are the most efficient adsorbents of herbicides used in Vidarbha. The adsorption capacity (mg/m) of BFA for removal of paraquat was found to be greater than that reported for natural adsorbents. Based on adsorption capacity, RHA and BFA dosages per hectare of land are recommended for different crops and fruits.