A comprehensive study on the application of graphene as capacitive deionization electrode for the removal of chloride

Abstract

In Tamil Nadu there are 17 major river basin which have been categorized as non-perennial. Hence it depends on rainfall for its replenishment and the average rainfall of Tamil Nadu is estimated as 917.8 mm. If there is continuous rainfall with a yield of average rainfall, even then, the amount of surface water received will be able to tackle only 36% people s domestic demand. So the prevailing status of surface water make us to depend on other reliable resource which is none other than subsurface water. Out of 232 available subsurface potential, 75.43% reaches over exploitation status and only the remaining 24.57% is in rechargeable condition. The existing rechargeable subsurface potential is also not in a condition capable of supplying water in portable quality. Most of the subsurface potential which is in replenish condition, nearly 58.62% is affected by salinity. Thus the current scenario of surface water and subsurface water necessitates to rely on an alternate potential capable of supplying water to take care of all purposes without any interruption. Sea Water is one such source, which is capable of providing abundant water throughout the year but the presence of salt reduces the utility of it. Hence treatment required for the reduction of salt concentration is unavoidable to make it portable. Most commonly the conventional treatment process like Ion Exchange Process, membrane process and thermal processes such as Multi-Stage Flash (MSF), Multi-Effect Distillation (MED) are adopted to reduce the concentration of salt from subsurface water as well as from sea water. However, these technologies are able to tackle only one percent of world s water demand and this limited contribution is due to the cost incurred in providing energy during desalination. Apart from high investment, most of the existing industrial scale desalination facilities get their energy from the combustion of fossil fuels, which in turn exchange potable water for CO2 newline