Comparative Study of Almond Shell Raw Activated Carbon, Chemically Activated and Adsorption of Anionic Dye from Wastewater

This study aims to use a biomaterial based on almond shells to prepare two types of activated carbon (AC), raw (rAC) and activated by 85% H₃PO₄ (cAC). These activated carbons were employed as adsorbents to treat an aqueous solution containing the Methyl Orange (MO) dye through the adsorption process. The study examined the influence of various factors such as pH, contact time, temperature, adsorbent material quantity, and initial concentration of Methyl Orange on the adsorption phenomenon. Experimental results revealed a rapid elimination phase within the first few minutes for both types of carbon, raw and chemically activated. At an ambient temperature of 25°C, with a mass of 1 gram, a concentration of 20 mg/L, and an agitation speed of 250 rpm, the maximum adsorption efficiency for the dye reached 94.3%. Chemical activation significantly improved the efficiency, reaching 98.30% for all variables studied. These findings underscore the efficacy of the biomaterial used as an adsorbent for liquid effluent treatment.