A Statistical Approach to Optimization of Congo Red Dye Removal (CRDR) Via Coconut Shell Activated Carbon (CSAC)

摘要

The use of low-cost, locally available, highly efficient and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from waste water. The aim of this work was the production of coconut shell activated carbon of Congo Red (CR) dye from aqueous solution. Batch adsorption studies were carried out by observing the effects of temperature and time, and the optimal experimental conditions were ascertained. Variables such as the adsorbent dose, initial concentration of solution and pH of solution were kept constant at 1 g, 100 mg/L and 7, respectively. The adsorptive capacity and percentage colour removal was mathematically described as a function of experimental parameters and was modelled through central composite response surface methodology (CCRSM). Results showed that the adsorption capacity and the percentage colour removal increased with an increase in time and temperature. The statistical predicted optimum values were validated by carrying out three experiments and an average Congo red (CR) of 86.82% and adsorption capacity (AC) of 8.50 mg/l were obtained at a time (Xsub1/sub) = -1 and a temperature (Xsub2/sub) = -1. The coefficient of determination (Rsup2/sup) and R-Sq. (adj.) for CR found in this study were 98.28% and 97.05%, while that for AC were 87.85% and 79.16%, respectively. Thus, the study concluded that the adsorbent was found to be effective, viable and suitable for the removal of Congo Red Dye from aqueous solution and its statistical analysis increased its optimum yields.