Removal of organic matter is normally done by activated sludge process in conventional plants. Studies have revealed that these plants are not effective and there is need for advanced treatment method for tackling the problem. The present work includes review of some investigations on various advanced methods for COD removal. Also experimental resluts of batch and column experiments for COD removal by using groundnut shell adsorbent are reported in the present paper.The parameters affecting the adsorption were studied and optimum values of these parameters were estimated. For the initial 0.5 to 1.5 grams of adsorbent,comparatively steep drop in concentration is observed. The central part of the curve indicates almost linear drop in COD with increase in adsorbent dosage.At lower pH, the H⁺ ions compete with adsorbate for the sites. At higher pH, there can be formation of complex ions or there can be hydroxides formation and subsequent precipitation also.