Cod removal by rice husk activated carbon

Wastewater from industrial, agricultural, and urban activities is channeled directly into the streams. High Chemical Oxygen Demand (COD) level in water indicated a vast amount oxidizable matter that consume a lot of dissolved oxygen in water. This results in adverse impacts on both aquatic ecosystems and human health. Wastewater from the fish cracker industry typically has high organic content and high COD value. In this study, rice husk was chose as adsorbent for it is abundance and economical. This study emphasized on the optimum adsorption parameters such as flow rate, time and initial COD concentration that affecting adsorption by rice husk activated carbon. Response Surface Methodology was used to optimize the variables affecting COD removal percentage. Activation of rice husk by phosphoric acid was done after it was carbonized at 450 °C for 2 h. The treatment was done in a continuous fixed bed column. The wastewater’s WQI value was calculated to be 11.82 and thus considered as polluted. From the Box-Behnken design, it was determined that a high 68.09 % removal percentage resulted from a best combination of 4.5 hours’ time, 1 ml/min of flowrate, and 5 % initial COD concentration. SEM micrograph shows the adsorbent consists of large amounts of pores. Based on the study, rice husk activated carbon is proved to be a good COD absorbent.