EVALUATION OF AGRICULTURAL AND INDUSTRIAL CARBONACEOUS WASTE AS ADSORBENT PRECURSOR FOR DYE REMOVAL APPLICATIONS

摘要

Dyes are widely used in textiles, paper, rubber, plastics, leather, cosmetics, pharmaceutical and food industries. The discharge of colored wastewater from these industries into natural streams has caused many significant problems such as increasing the toxicity and chemical oxygen demand (COD) of the effluent, and also reducing light penetration, which has a derogatory effect on photosynthetic phenomena [1]. Several methods are available for removal of dyes from wastewater.The most efficient method for the removal of sythetic dyes from aqueous effluents is the adsorption procedure. This procedure transfers the dye species from the water effluent to a solid phase thereby keeping the effluent 4 volume to a minimum. Subsequently, the adsorbent can be regenerated or stored in a dry place without direct contact with the environment[2]. Activated carbon is the most employed adsorbent for dye removal from aqueous solution because of its excellent adsorption properties. The high adsorption capacity of an activated carbon is associated with its high surface area and porous structure. Besides these physical characteristics, the adsorption capacity is also dependent from source of the organic material employed lor the production of the activated carbon, as well as the experimental conditions employed in the activation processes. However, the extensive use of activated carbon for dye removal from industrial effluents is expensive, limiting its large application for wastewater treatment. Therefore, there is growing interest in finding alternative low-cost adsorbents for dye removal from aqueous solution[3]. In this study removal of methylene blue from aqueous solutions was performed with different fruit shell chars. Almond, pistachio and peanut shells were used to produce carbon chare. The effects of different fruit shell chars on adsorption efficiency was examined and equilibrium data of the adsorption process was studied.