Solid-phase Extraction of 4-Nitrophenol from Aqueous Solution by Brachystegia eurycoma Seed Hulls

The adsorption of 4-Nitrophenol in aqueous solution by B. eurycoma seed hull was studied under the influence of environmental factors. Our result showed that 0.5 g B. eurycoma seed hull can effectively achieve 98% removal of 4-Nitrophenol at pH 12, temperature 25°C, 40 mins contact time, 8 mg/Linitial concentration of 4-Nitrophenol. From the data obtained in this research, the adsorption process did not fit into the Langmuir isotherm (RL value = 0.002593) but followed the Freundlich isotherm (n = 2.04). This showed that B. eurycoma seed hulls can be used to adsorb 4-nitrophenol from aqueous solution and also used in environmental phytoremediation.