Investigation of Moringa Oleifera as Potential Green Coagulant for Removal of Phenol from Aqueous Solution

Highly water-soluble phenols have not satisfactorily been removed by current
physical or chemical treatment of water thus a new approach using coagulation with a
natural coagulant was investigated in this study. The need for alternative coagulant was
crucial because conventional coagulant produce high amount of sludge which is nonbiodegradable.
The seed powder of a pan tropical tree, Moringa Oleiftra was tested as a
natural coagulant for phenol removal in wastewater treatment. Natural coagulants are
more environmental friendly and produce lesser amount of sludge. The use of this
coagulant was assisted by coagulants aids like bentonite and lime.
Phenol contaminated wastewater was treated using the enhanced coagulation
method. The experiments had been carried out by varying few parameters like dosage of
coagulant (Moringa Oleiftra), pH, temperature and effect of coagulant aids (lime and
bentonite). Series of jar test had been conducted with 3 minutes of rapid mixing at 200
rpm, followed by 30 minutes of slow mixing at 45 rpm and 1 hour of settling process.
Afterwards, the solution was tested for phenol level, Chemical Oxygen Demand (COD)
and amount of sludge produced.
The optimum condition for the process was at 4000ppm of Moringa Oleifera, pH
11 at room temperature and lime as coagulant aid at 2000ppm. The phenol removal
percentage was 77%, COD reduction percentage was 70% and 0.7324g sludge was
produced at the optimum condition.