Utilisation of Chemically Activated Maize Tassel For Remediation of Eutrophic Phosphorus
Chemical precipitation with lime, the technology of choice for phosphate removal from contaminated waters, is expensive. In this study the feasibility of utilizing low-cost chemically activated maize tassel for the adsorptive removal of phosphate was assessed. H3PO4 was added to maize tassel powder in the impregnation ratio 2:1(w/w H3PO4: tassel) and activated at 600°C under an inert atmosphere of N2. The activated product was characterized by BET. Activation resulted in an increase in specific surface area from SBET 2.54 to 803.8 m2/g. Batch experiments were performed to study the removal of phosphate from simulated samples; the optimal parameters were found to be: contact time of 90 min, pH 7 and adsorbent dosage of 1.5 g per 100 mL solution. The adsorption data were fitted to the Langmuir isotherm model (R2 > 0.99), yielding an estimated adsorption capacity of 15.41 mg PO43- (as P) per g adsorbent. The activated product was successfully applied for the remediation of phosphate in selected sewage samples.
Keywords- Maize tassel, chemical activation, eutrophication, phosphate removal.