Gas Sparged Adsorber for Decolourization Dye Effluent

Abstract

The adsorption of basic dyestuff (Maxilon Red BL-3) from aqueous solution at 25 °C onto natural clay was studied. The clay showed high performance for dye removal, the maximum adsorption capacity of the natural clay was found to be 326 mg dye per g of natural clay. The experimental data were fitted to the Freundlich and Langmuir isotherm models. The best fitting isotherm was found to be the Langmuir isotherm. Mass balance calculation was carried out and the operating lines were used to calculate the amount of clay needed per unit volume of dye solution to reach the effluent concentration target. Gas sparged technique was proved to be very efficient technique, thus it was used to study the rate of dye removal from its solution using clay as adsorbent. A series of contact-time experiments was undertaken in a batch adsorber to assess the effect of the system variables, namely, gas flow rate, initial dye concentration, mass of clay and temperature of the solution, on the overall volumetric mass transfer coefficient. The study revealed that dye removal is diffusion controlled process.