Removal of nickel (II) from aqueous solutions by Sargassum filipendula biomass in multiple cycles of sorption-desorption - DOI: 10.4025/actascitechnol.v31i1.840

Abstract

The behavior of seaweed Sargassum filipendula during a removal of nickel from a 50 mg/L aqueous solution at pH 3.5 in fixed-bed columns operating in adsorption/desorption cycles has been studied. Two elution systems were tested; the first one operating with the direct passage of eluant and the second one with the solution recycle.Then, ten consecutive sorption-desorption cycles were investigated in two packed-bed columns, the first column was regenerated with H2SO4 (0.1 M) and the second one with MgSO4 / H2SO4 (3.5% in pH 3) in eluant recycle system. The sorption and desorption stages were carried out for about 30h and 2 h, respectively, representing 20 days of a continuous use of the biomass. A high quantity of recovered nickel was observed in the elution stages (approximately 97%). After 10 cycles, it was verified that the Sargassum filipendula biomass continued accomplishing elevated values of nickel removal from the solution, showing to be an efficient alternative treatment of wastewaters containing metals. The biomass is easily found and the regeneration presented low cost besides having facilitated the treatment process dispensing successive biomass changes.