Characterization and use of in natura and calcined rice husks for biosorption of heavy metals ions from aqueous effluents

Abstract

-Heavy metal removal by adsorption using rice husks as a bioadsorbent was evaluated as an alternative for wastewater treatment. Batch equilibrium experiments and kinetic sorption studies were performed using monocomponent solutions of Ni(II), Cd(II), Zn(II), Pb(II) and Cu(II) in surface samples of in natura (RH) and calcined rice husks (RHA). RHA showed higher potential for removing lead and copper. Experimental data for adsorption isotherms of lead and copper were adjusted by Langmuir, Freundlich and Dubinin-Radushkevick (D-R) models, being better represented by the Langmuir model. The calcination of RH increased its surface area, improving its adsorption properties. From a morphological analysis obtained by SEM and diffraction patterns (XRD), a longitudinal fibrous and amorphous structure was observed for RH. TGA results indicated a total mass loss of around 60% for RH and 24.5% for RHA.

Kinetic modelling of cadmium and lead removal by aquatic mosses

“…Various low cost adsorbents have been investigated for removing Cd, Pb and other metals from aqueous solutions: bentonite (Naseem and Tahir, 2001), expanded perlite (Torab-Mostaedi et al, 2010), mud (Salim, 1986), volcanic ash soil (Cajuste et al, 1996), pine bark (Al-Asheh et al, 1998), waste tire rubber ash (Mousavi et al, 2010), freshwater macrophytes (Schneider and Rubio, 1999), bacteria (Yilmaz et al, 2010), aquatic mosses (Al-Asheh et al, 1998;Martins and Boaventura, 2002), peat moss (McKay and Porter, 1997), alum sludge (Chu, 1999), soybean hulls, cottonseed hulls, rice straw and sugarcane bagasse (Marshall and Champagne, 1995), rice husk (Vieira et al, 2012;Senthil Kumar et al, 2010), olive stones (Calero et al, 2009), activated carbon from lignocellulosic residues (Giraldo and MorenoPiraján, 2008;Attia et al, 2010). The literature shows an extensive list of biomass used in metal biosorption; the novelty of this work is exactly the use of an aquatic moss, a less studied material.…”

Removal of the synthetic dye Remazol Brilliant Blue R from textile industry wastewaters by biosorption on the macrophyte Salvinia natans

“…Many studies have been developed in order to seek low-cost adsorbents such as peat, ash, wood chips, silica, and clays . The use of biomaterials as adsorbents for the treatment of wastewater is a potential alternative to conventional treatments (Vieira et al, 2014;2012;Mafra et al, 2013;Pelosi et al, 2013;Piccin et al, 2011;Kumar et al, 2005;Moreira et al, 2001). However, these low cost absorbers typically have low adsorption capacity (Srinivasan and Viraraghavan, 2010).…”

Biosorption study of Ni2+ and Cr3+ by Sargassum filipendula: kinetics and equilibrium

“…Experimental studies on biosorbent selection for heavy metal removal include bacteria, yeast, fungi, and algal and plant derived materials (Farooq et al, 2010;Vieira et al, 2012). Moreover, studies in which seaweed is used, especially the Sargassum species, confirm that this biomass can remove several metallic ions (chromium, cadmium, copper, nickel, zinc etc.)…”