Response Surface Methodology as a Tool to Study the Removal of Amido Black Dye from Aqueous Solution using Anionic Clay Hydrotalcite

Abstract

Anionic clay hydrotalcite was used as an adsorbent to remove amido black dye from aqueous solutions. Response surface methodology (RSM) based on a five-level, four-variable Central Composite Rotatable Design (CCRD) was employed to evaluate the interactive effects of various optimization parameters. The parameters were contact time (6-10 hrs), solution pH (4-8), adsorbent dosage (200-600 mg) and dye concentration (50-100 mg/I). Simultaneously increasing contact time, initial concentration and amount of adsorbent dosage increased the quantity of amido black dye removed. The optimum conditions derived via RSM for the reaction were a reaction time of 8.48 hrs, a concentration of 58. 09 mg/I, an adsorbent dosage of 431. 2 4 mg/L and a solution pH of 6.27. The experimental percentage removal was 85.55 % under optimum conditions, which compares well with the maximum predicted value of 87.95 %.