Removal of arsenic (V) from aqueous solutions using chemically modified sawdust of spruce (Picea abies): Kinetics and isotherm studies

Abstract

ABSTRACT:Arsenic is a ubiquitous element in the environment and occurs naturally in both organic and inorganic forms. Under aerobic condition, the dominant form of arsenic in waters is arsenate, which is highly mobile and toxic. Arsenic poisoning from drinking water remains a serious world health issue. There are various standard methods for arsenic removal from drinking waters (coagulation, sorption, ion-exchange reactions or methods of reverse osmosis) and alternative methods, such as biosorption. Biosorption of arsenic from natural and model waters by native or chemically modified (with urea or ferric oxyhydroxides) plant biomass prepared from sawdust of Picea abies was studied. The kinetic of the adsorption process fitted well the pseudo second order adsorption model and equilibrium was achieved after 2 h. The results showed that biosorption was well described by both Langmuir and Freundlich isotherms. The maximum biosorption capacity of the sawdust modified with ferric oxyhydroxides, evaluated by Langmuir adsorption model, was 9.259 mg/g, while the biosorption capacity of unmodified biosorbent or biosorbent modified with urea was negligible. The adsorption capacity is comparable to results published by other authors, suggesting that the prepared chemically modified biosorbent has potential in remediation of contaminated waters.

Biosorptive behaviour of mango leaf powder and rice husk for arsenic(III) from aqueous solutions

“…The low-frequency bands around 1,550 cm -1 indicating the presence of amino groups. The surface complex formation between dissolved metal ion species and surface functional groups with biosorption capacity is a function of its density as well as the nature of metal ions in solution (Urik et al 2009). Figure 2b shows the FTIR analysis for As(III)-loaded MLP biomass.…”

“…6a, b for As(III)-MLP and As(III)-RH systems could be fitted well for the pseudosecond-order (R 2 = 0.986-0.999) model of adsorption rate. However, the best adjustment was observed for the pseudosecond-order kinetic which is based on the assumption that rate limiting step is chemisorption involving valance forces through sharing or exchange of electrons between As(III) ion and the adsorbent provides the best correlation data for the As(III) ion (Urik et al 2009). Similar phenomenon has been observed in the biosorption of heavy metals onto untreated coffee husks (Oliveira et al 2008).…”

“…As it can be seen, the Freundlich isotherm gave better fits than the Langmuir isotherm, which illustrated that the biosorption on the surface of MLP and RH was a multilayer biosorption. Urik et al (2009) and Mondal et al (2006) reported the mechanism of As(III) adsorption onto modified sawdust and granular activated carbon seem to be formation of inner and outer sphere surface complex. Thus, the formation of chemical bond present in the surface of biomass and metal ions.…”

Arsenic in soil, vegetation and water of a contaminated region

“…The occurrence of high concentrations of arsenic (As), one of the most hazardous chemical elements in drinking water has been recognized, over the past two or three decades, as a great public health concern in several parts of the world (Mukherjee et al, 2006;Urík et al, 2009). Seventy five percent of the samples taken from the wells in the study areas contained As at concentrations higher than 100 µg/L (Table 1), greatly exceeding the maximum allowed limit for drinking waters (50 µg/L) (USEPA, 1980;WHO, 1993 and1996 Ranunculus arvensis 7 6.22 ± 0.6 9.62 ± 0.5 ND Table 3: Arsenic concentration in leaf samples collected from three contaminated areas in Bijar County Natural contamination of surface waters with As, has been recognized before in some villages in Bijar and Qorveh districts (Mosaferi et al, 2003).…”

Arsenic(III) removal from aqueous solution by raw and zinc-loaded pine cone biochar: equilibrium, kinetics, and thermodynamics studies

“…The toxicity of As exists greatly in its oxidation states (-3, 0, ?3, and ?5), and the trivalent form [As(III)] is recognized as most hazardous state (Manju et al 1998). The World Health Organization (WHO), the European Union (EU), and several countries including Japan, India, China, Bangladesh, and Vietnam have recommended its maximum contaminant level (MCL) of 10 lg L -1 in drinking water Urík et al 2009;Mafu et al 2013).…”