Sustainable Bio-Adsorbent for Treatment of Nitrate, Fluoride and TDS in Groundwater

Abstract

The quality of groundwater and surface water bodies have been analyzed globally and showed that 23% of primary drinking water sources have more than permissible limits of pollutants’ concentration. A major part of the world suffers from high concentrations of Nitrate, Fluoride and total dissolved solids (TDS) in drinking water. Therefore, the present work focuses on the treatment of these three parameters. There are many processes available to remove and reduce the higher concentration of the aforesaid pollutants in water with advantages and disadvantages. One of the main disadvantages of these processes is the sustainability and availability of treating materials. In this regard, the work explores different agricultural materials (nine to be exact) for reduction of Fluoride, Nitrate and TDS in water. It is found that most of the materials have the potential to reduce either of one contaminant. However, only potato gel has shown potential in reduction of all three contaminants', i.e. Fluoride, Nitrate and TDS, concentration. The Isotherm plots indicate that Nitrate and TDS biosorption mechanism follows the Langmuir Isotherm while Fluoride biosorption follows the Freundlich Isotherm. Optimization is carried out, using batch and continuous study, in terms of time and mass of adsorbent against the concentration of the contaminant. Adsorption column tests indicate the reduction of 89%, 92% and 86% in the concentration of Fluoride, Nitrate and TDS respectively by potato gel.