Predictive Modeling and Comparative Studies on Different Methods for Dyes Removal from Wastewater

Abstract

The need to reduce the cost of adsorption technology has led scientists to explore the use of many low cost adsorbents obtained from various sources. Natural plant materials have been identified as potentially low cost and efficient adsorbent materials for the removal of dyes from coloured effluent. The aim of this study was to prepare a low cost adsorbent from the roots of an aquatic weed water hyacinth and subsequently evaluate its efficacy as adsorbents for dye removal from aqueous solution. newlineThe removal of dyes namely Methylene Blue (MB), Malachite Green (MG), Crystal Violet (CV), Congo Red (CR), Acid Blue 25 (AB 25), Direct Black 168 (DB 168) and Reactive Orange 16 (RO 16) from aqueous solution by batch adsorption technique using Water Hyacinth Root Powder (WHRP) as adsorbent was investigated. As the objective of the study was to find out a suitable low cost, environmental friendly and effective adsorbent to treat coloured effluent, in the present study adsorption efficiency of low cost adsorbent WHRP was determined. The influences of pH, adsorbent dose, initial adsorbate concentration and contact time on the adsorption process were investigated. The physicochemical properties of the adsorbents were studied using different characterization techniques Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). newlineThe pH of the dye solutions were varied to get optimum pH for all experimental dyes. Adsorption process was found to be highly pH dependent. The maximum percentage removal of MB, MG, CV, CR, AB 25, DB 168 and RO 16 were obtained at pH : 8.0, 9.0, 8.0, 5.0, 2.0, 2.0 and 3.0 respectively. newlineResults from adsorbent dose and percentage removal relationship shows that percentage removal increases with increase in adsorbent dose up to equilibrium and afterward there were no significant changes observed on increasing adsorbent amount. Further, in all the cases the uptake capacity showed a reverse trend with increase of adsorbent concentration. newline