Removal of cesium, lead, nitrate and sodium from wastewater using hydroponic constructed wetland

Hydroponic constructed wetlands are effective alternative technology for water and wastewater treatment. In the present research, Chenopodium album, Amaranthus cruentus, Phragmites australis and Bambusa vulgaris plants were used in hydroponic constructed wetland for phytoremediation of cesium, lead, nitrate and sodium from synthesized wastewater. During the treatment of wastewater containing CsCl and Pb(C2H3O2)(4), 59.57 +/- 2.12% cesium and 95.32 +/- 1.32% lead were remediated by Amaranthus cruentus at a period of 14 days. Initial concentration of CsCl and Pb(C2H3O2)(4) was 0.5 mg L-1. In wastewater containing 5 mg L-1 CsCl and 5 mg L-1 Pb(C2H3O2)(4), Cs phytoremediation efficiency was 49.11 +/- 3.78%. Simultaneously, 98.40 +/- 0.05% Pb was removed in a period of 14 days. In mesocosm constructed wetland vegetated with Phragmites australis and Bambusa vulgaris, 46.28 +/- 0.005% nitrate was taken up by Bambusa vulgaris and 35.80 +/- 0.01% nitrate was removed by Phragmites australis from wastewater containing 1000 mg L-1 KNO3 and 2000 mg L-1 NaCl in a period of 14 days. In the case of desalination, sodium uptake efficiencies by Phragmites australis and Bambusa vulgaris were 16.73 +/- 0.56% and 32.62 +/- 2.56%, respectively. In all the experiments, cesium shoot accumulation was more than root, while lead accumulated in roots more than shoots. The results also show that hydroponic constructed wetlands vegetated with terrestrial and aquatic plants are promising technology for wastewater treatment.