The main goal of this research was to prepare composts from neem (Azadirachta indica A. Juss) leaves and water hyacinth plant for the remediation of Basic Blue 41 (BB41) bearing wastewaters. The process of composting was performed using Effective Microorganisms (EM) for neem tree leaves (EM LC ) and water hyacinth waste (EM WHC ). Through preliminary experiments, for biosorption of BB41, 1.18 mm and 2 g/L were identified as the optimum particle size and compost dosage, respectively. The pH edge experiments revealed that pH 8 as optimum for BB41 biosorption and the isotherm experiments indicated that EM LC and EM WHC can biosorb 456.8 and 158.0 mg/ g, respectively, according to the Langmuir model. The isotherm data were further examined using the Freundlich, Sips, Toth and Redlich-Peterson models, with the later produced high R 2 values and good prediction. Biosorption of BB41 onto EM LC and EM WHC was rapid with 90% BB41 removal was achieved within first 90 and 120 min of contact, respectively. The biosorbed BB41 was effectively desorbed from EM LC and EM WHC using HCl, HNO 3 , H 2 SO 4 , NaOH and CaCl 2 with desorption efficiencies greater than 94%. Both EM LC and EM WHC were also regenerated and re-used for BB41 biosorption in three consecutive sorptiondesorption cycles.

Due to the weathering of rocks, effluents from industries and geochemical responses the fluoride interacts with the ground water. Precipitation, adsorption, ion-exchange, membrane process techniques helps to process defluoridation in water. Among these fluoride removal strategies, adsorption technique is direct, reasonable, and appropriate for drinking water treatment. A few adsorbents, for example, activated carbon and alumina, agricultural and industrial wastes etc., were endeavor the permissible range of fluoride availability in water by adsorption technique. Use of plant related materials and agricultural wastes as adsorbents are commonly involved in adsorption technique since these materials are easily available with biodegradable nature and also they are inexpensive materials. The principle reason for this literature survey is to give new thoughts regarding the defluoridation in aqueous solutions by adsorption method which was analyzed by numerous analysts. In this review paper, different adsorbents has been reviewed and their adsorption efficiency based on pH, initial fluoride concentration, temperature, contact time has been analysed. It is obvious from the review that the various adsorbents have demonstrated incredible capability of defluoridation. Be that as it may, at present there is an earnest requirement for the identification and improvement of progressively novel adsorbents which depends on economic and innovative aspects.