Remoção de níquel (II) de soluções aquosas pela biomassa Sargassum filipendula em múltiplos ciclos de sorção-dessorção

Abstract

The behavior of seaweed Sargassum filipendula during a removal of nickel from a 50 mg L-1 aqueous solution at pH 3.5 in fixed-bed columns operating in adsorption/desorption cycles was 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 an eluant recycle system. The sorption and desorption stages were carried out for about 30 and 2h, respectively, representing 20 days of 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 to accomplish elevated levels of nickel removal from the solution, proving to be an efficient alternative treatment for wastewaters containing metals. The biomass is easily found and the regeneration presented low cost, in addition to having facilitated the treatment process by not requiring successive biomass changes.