Adsorption of Metanil Yellow Using Flavonoid Extract from Longan Peel (Dimocarpus longan): Optimization of pH and Concentration

Water pollution can come from industrial waste containing various toxic pollutants, one of which is dye. Hazardous dyes are stable and resistant to biodegradation due to their complex aromatic structure, so dyes need to be treated. Metanil Yellow is a dye that is harmful to aquatic life and the human body. One method that can be used is adsorption with the batch method because it has the advantage of low cost and simple processing. Flavonoid extracts have high potential to be used as biosorbents because they have hydroxyl and carbonyl groups. This study aims to determine the potential of flavonoid extracts to adsorb metanil yellow dye using optimum pH and solution concentration and to determine its absorption capacity. The results showed that the optimum pH obtained was at pH 2 and the optimum solution concentration was at 150 ppm with an absorption capacity of 9.22078 mg/g.