Application of Moringa peregrina seed extract as a natural coagulant for phenol removal from aqueous solutions

Abstract

Phenol and its derivatives are toxic pollutants frequently found in surface and tap waters, and in aqueous effluents from various manufacturing processes such as petroleum and petrochemical, coal conversion, synthetic rubber, plastics, paper, oil refineries and phenol-producing industries. In the present study, the ability of Moringa peregrina seed extract to remove phenol from aqueous solutions in a batch system was investigated. The effects of major operating variables such as coagulant dose (0.05 - 4 ml//L), initial phenol concentration (5, 10, 20, 50 and 100 mg/L) and pH (3-9) were investigated. The optimum pH for phenol removal by coagulation using M. peregrina seed extract was 5, with coagulant dose of 0.1 and 0.3 ml/L and the highest removal was found to be 95.16, 95.84, 97.91, 98.27 and 99.9% at initial phenol concentration of 5, 10, 20, 50 and 100 mg/L, respectively, as a result of precipitation, co-precipitation and adsorption mechanisms. According to these results, it was defined that M. peregrina seed extract is not only an inexpensive coagulant, but also quite an effective factor in the removal of phenol from aqueous environments.

Key words: Phenol removal, Moringa peregrina, coagulation, natural coagulants.