Executive Summary : | The advanced treatment technologies adopted for dye wastewater treatment involve high operating and maintenance cost. Micro and small-scale industries are reluctant to bear the additional cost for these treatment units. Thus, there is a need to provide a cost-effective feasible solution to such industries that would encourage them not to discharge the polluted streams in nearby areas rather to treat and reuse the water. Adsorption, owing to its ease of operation and low maintenance cost, is a viable method to treat dye contaminated streams. In this regard, a number of conventional and low-cost adsorbents have been investigated but these studies are limited up to a binary and ternary systems and may not be much effective to treat the actual effluent which is a multicomponent mixture. This proposal is intended to provide a low-cost continuous multi-bed adsorption technology to the micro and small-scale industries. Preliminary experiments indicate that with the developed material, high concentration of anionic dyes may be removed followed by adsorption of cationic dyes. These results triggered the idea of developing a multi-bed adsorption column in which a multicomponent mixture of cationic, anionic, and non-ionic dyes may be adsorbed in a sequential manner. The basic purpose of the proposed work is to gain in-depth understanding of the process including the thermodynamics, kinetics, equilibrium, and competitive effects. The study is required before the process is scaled up for commercialization. Our group has already carried out batch and continuous studies for selective removal of anionic dyes from a binary mixture of cationic-anionic dyes. Further studies are suggested for removing multicomponent mixture of dyes with different charge groups using multibed column studies. |