The removal of dye colours from aqueous solutions by adsorption on low-cost materials

The ability of five low cost adsorbents - rice husk, cotton, bark, hair and coal - to adsorb two basic dyes, namely, Safranine and Methylene Blue, has been studied. Equilibrium isotherms have been determined and analysed usin g the Langmuir equations. The monolayer saturation capacities for Safranine are 1119, 838, 875, 190 and 120 mg g(-1) adsorbent and for Methylene Blue are 914, 312, 277, 158 and 250 mg g(-1) adsorbent for bark, rice husk, cott on waste, hair and coal respectively. A limited number of fixed bed column studies have been performed and the bed depth service time for each dye-ads orbent system has been determined.