Eco-friendly waste water purification using brown algae

Abstract

ABSTRACT Three brown algal biomasses namely, Sargassum latifolium, Padina pavonica and Dictyota dichotoma were used in the uranium biosorption from the processing effluent of Gattar pilot plant project, Eastern Desert, Egypt. Biosorption enhancement process was studied, and the uranium loading capacities were optimised at 1 h contact time, 1/1000 solid/liquid ratio, 200 ppm uranium as initial feed concentration, pH 4 and all experiments were at room temperature. The maximum capacities reached 190, 177 and 170 mg/g for Sargassum latifolium, Padina pavonica and Dictyota dichotoma, respectively. SEM examination for the three concerned algae showed different morphological and surface structural changes such as shrinking and appearance of large cavities. FTIR study revealed that, there are many functional groups contributed in uranium biosorption mechanism such as carboxylic, sulphonate, hydroxyl and amine groups. The obtained experimental data for the three concerned algal biomasses were comparable with pseudo-second-order model and best described by Langmuir isotherm model. 0.1 N HCl was used for desorption of the loaded uranium on the three algal masses. By applying the most effective alga (Sargassum latifolium) with fixing the optimum concluded conditions in the treatment of Gattar pilot plant effluent, it was clear that almost all elements and nearly uranium complete concentrations were recovered from the waste water and the water can be safely reused again. The present work concluded that the phyco-sorption is a sufficient, low costing, eco-friendly way for the recovery of variable elements and purification of waste water solutions.