Ecological Engineering 93 (2016) 112–119 Contents lists available at ScienceDirect Ecological Engineering jo ur nal home p ag e: www.elsevier.com/locate/ecoleng Selected heavy metal biosorption by compost of Myriophyllum spicatum—A chemometric approach Jelena Milojkovi ´ c a,∗ , Lato Pezo b , Mirjana Stojanovi ´ c a , Marija Mihajlovi ´ c a , Zorica Lopiˇ ci´ c a , Jelena Petrovi ´ c a , Marija Stanojevi ´ c a , Milan Kragovi ´ c a a Institute for Technology of Nuclear and Other Mineral Raw Materials, 86 Franchet d’Esperey St. Belgrade, Serbia b Institute of General and Physical Chemistry, University of Belgrade, Studentski Trg 12 - 16, 11000 Belgrade, Serbia a r t i c l e i n f o Article history: Received 7 September 2015 Received in revised form 3 March 2016 Accepted 4 May 2016 Available online 20 May 2016 Keywords: Heavy metal removal Compost Myriophyllum spicatum Chemometric analysis a b s t r a c t In this study adsorption characteristics of lead, copper, cadmium, nickel and zinc ions onto the compost of Myriophyllum spicatum were examined. The effects of sorbent dose, duration of sorption and solution con- centration on the sorption of heavy metals have been investigated. Scanning electron microscope (SEM) and thermogravimetric and differential thermal analysis (TG-DTA) were used for the characterization of this biosorbent. Low coefficients of variation have been obtained for each applied assay, which confirmed the high accuracy of measurements. Principal component analysis (PCA) was applied for differentiation of samples. Mathematical models (form of second order polynomials) were developed for prediction of adsorption. Score analysis is being useful for accessing the effect of process parameters and the tool for determination of sorption quality. On the basic of experimental results and model parameters, it can be concluded that compost has a high biosorption capacity can be utilized for the removal of selected metals from wastewater. © 2016 Elsevier B.V. All rights reserved. 1. Introduction Biosorption was proven to be cost-effective and eco-friendly technology, which engages the use of biological materials for the treatment of wastewater (Kiran and Thanasekaran, 2011). Appli- cation of efficient natural materials is more cost effective than artificial materials (Turan and Altundo˘ gan, 2014). Different biosor- bents (raw or modified) were tested for the removal of various pollutants. Most studies of biosorption were primarily focused on heavy metal and dye pollutants (Anastopoulos and Kyzas, 2015). Amongst the various technologies for removal of toxic metals from wastewaters, it really represents an inexpensive alternative, because of the application of low-cost materials as sorbents (Veglio et al., 1998). Majority of the research in the biosorption of heavy metals refers to the removal of divalent cations (Michalak et al., 2013). Diva- lent heavy metal cations are widespread in ground and surface waters, soils and sediments due to human activity. Furthermore, like divalent cations, heavy metals can easily enter in the food chain, producing different toxic effects on living organisms (Smiciklas ∗ Corresponding author. E-mail addresses: j.milojkovic@itnms.ac.rs, jelenavmilojkovic@gmail.com (J. Milojkovi ´ c). et al., 2008). High solubility of heavy metals in the aquatic sur- roundings allows their adoption by living organisms (Babel and Kurniawan, 2004). The most important factors which affect to heavy metal mobility, toxicity, and reactivity are: pH, sorbent nature, Eh, temperature, presence and concentration of organic and inorganic ligands, etc. (Tessier et al., 1979). Chemical speciation of metal is determined by solution pH. For instance, lead is present as Pb(II) as dominant species at pH < 5.5 (Farooq et al., 2010). Metal species of selected heavy metals (Pb, Cu, Cd, Ni and Zn) are in the +2 oxidation states in aqueous solution where pH is around 5.0 (Vieira et al., 2012). The solubility of heavy metals determines their tox- icity. The metals are more toxic at lower pH values, because then their solubility increases (Beˇ celi ´ c and Tamaˇ s, 2004). Taking into account heavy metal mobility, toxicity, and reactiv- ity for this study Pb(II), Cu(II), Cd(II), Ni(II) and Zn(II) were selected. Among different biosorbents, the researchers consider on alter- native application of composts. It is well known that composts are mainly used as amendments to increase soil fertility (Anastopoulos and Kyzas, 2015). There is a constant increase in the number of papers in which compost is used as biosorbent of pollutants. Compost of M. spicatum can be successfully applied as biosor- bent for Pb(II) Milojkovi ´ c et al. (2014a) and selected heavy metals (Pb(II), Cu(II), Cd(II), Ni(II) and Zn(II)) (Milojkovi ´ c et al., 2014b). http://dx.doi.org/10.1016/j.ecoleng.2016.05.012 0925-8574/© 2016 Elsevier B.V. All rights reserved.