The release of light metals from a brown seaweed (Sargassum sp.) during zinc biosorption in a continuous system

Abstract

Financial support: CNPq (Conselho Nacional do Desenvolvimento Científico e Tecnológico), CAPES and UERJ (Universidade do Estado do Rio de Janeiro).Keywords: biomass, heavy metal, uptake, wastewater. * Corresponding authorThe biosorption of zinc and calcium was investigated with a biomass of Sargassum sp., a brown seaweed, in a continuous system consisting of three serial tubular fixed-bed laboratory reactors. Results indicated that zinc was efficiently recovered by the biomass. After treatment of 9.0 liters of a mixed solution containing 130.0 mg/l zinc and 260.0 mg/l calcium, the first column of the system saturated with zinc; the remaining columns did not saturate with zinc as a result of the pre treatment performed by the first reactor. Calcium was also efficiently biosorbed by the biomass, saturating the system much faster than zinc. X-ray fluorescence spectrum indicated the presence of various elements in the structure of the Sargassum sp. biomass, especially alkaline and alkaline-earth elements. Alkaline and alkaline earth elements played a key role in the biosorption of zinc, being responsible for ion-exchange reactions performed during zinc biosorption.Nonliving seaweed biomass can be used in the development of biosorbent materials to accumulate heavy metals. The biomass, in this case, must be selective, reusable and cheap, thus constituting an alternative technology for residual metal ions recovery. Non living biomass of seaweeds can be used for this purpose, being an efficient treatment for heavy metals contaminated effluents.For the uptake of heavy metals two different reactor configurations can be used: continuous stirred tank reactor and fixed bed columns.Even though the literature presents papers using bacteria (da Costa and Duta, 2001), algal cells (Schmitt et al. 2001), fungi (McAfee et al. 2001) and other biomaterials (Lister and Line, 2001;Schneider et al. 2001), little is known about the behavior of a continuous system, for this kind of treatment. The purpose of the present work was to investigate the behavior of continuous serial reactors for the uptake of zinc. As well, little is known about ion-exchange properties of the biomass. Most papers describe this process as a typical adsorption process, not investigating the

HybridSargassum-sand sorbent: A novel adsorbent in packed column to treat metal-bearing wastewaters from inductively coupled plasma-optical emission spectrometry

“…It is well known that seaweeds obtain these light metal ions from seawater. [25] High concentrations of Na, K, Ca and Mg are always related to TDS, water hardness, scale formation and water bitterness. [26,27] However, these light metal ions were well below the discharge standards (Table 1).…”

Growth responses of hydroponic green fodder system and Fusarium oxysporum to external supply of mycolytic enzymes applied on seaweed bagasse as carrier

“…This suggests that the observed effect can be attributed to water accumulated in bagasse, as well as to the presence of some additional nutrients contained in seaweed such as carbohydrates, minerals, some essential amino acids, and vitamins (Marín et al, 2009). Moreover, the components of Sargassum have the potential to accumulate metals (Costa et al, 2001); this capacity allowed that nutrients added during irrigation remain available for the period of HGF production. Considering the fungi count in studied systems (Table 3), it was possible to assume that height was not the parameter that was strongly affected by fungi presence probably due to F. oxysporum and fungi from environment require more time to penetrate the roots of HGF and to affect its growth.…”

Biomass and Phytal Animals of Floating

“…Sargassum spp algae contains mainly the polysaccharide alginate, usually calcium and sodium alginate, that is said to have the high potentials for the accumulation of heavy dissolved metals in the different water system [22]. The biosorbent with high adsorption process is generally rapid and it is suitable for the great extraction of metal ions from large volumes of water that is already accumulated [23]. A particular Sargassum species, S. muticum which is considered an invasive species is said to be the most accurate to use in the binding analysis with non great deal thermodynamically consistent absorption because of its high content of alginate [24].…”