Journal of Hazardous Materials 264 (2014) 153–160 Contents lists available at ScienceDirect Journal of Hazardous Materials jou rn al hom epage: www.elsevier.com/locate/jhazmat Fabrication of glycine-functionalized maghemite nanoparticles for magnetic removal of copper from wastewater Natálie C. Feitoza a , Thamires D. Gonc ¸ alves a , Jéssica J. Mesquita a , Jucely S. Menegucci a , Mac-Kedson M.S. Santos a , Juliano A. Chaker a , Ricardo B. Cunha b , Anderson M.M. Medeiros b , Joel C. Rubim b , Marcelo H. Sousa a,∗ a Universidade de Brasília, Faculdade de Ceilândia, Centro Metropolitano Conjunto A Lote 1, Ceilândia, DF, CEP 72220-900, Brazil b Universidade de Brasília, Instituto de Química, CP 04478, Brasília, DF, CEP 70919-970, Brazil h i g h l i g h t s • Glycine-functionalized magnetic nanoadsorbents are proposed for copper removal. • Nanoadsorbents present highly efficient removal of copper ions from wastewater. • Nanoadsorbents are magnetically separable and reusable for removal of copper. • Synthesis utilizes a cost-effective and environmentally friendly procedure. • Removal can be extended to other heavy metal ions from wastewater. a r t i c l e i n f o Article history: Received 4 September 2013 Received in revised form 7 November 2013 Accepted 10 November 2013 Available online 18 November 2013 Keywords: Magnetic nanoparticles Glycine-functionalized Wastewater Copper adsorption a b s t r a c t Maghemite nanoparticles (MNPs) were functionalized with glycine, by a cost-effective and environmen- tally friendly procedure, as an alternative route to typical amine-functionalized polymeric coatings, for highly efficient removal of copper ions from water. MNPs were synthesized by co-precipitation method and adsorption of glycine was investigated as a function of ligand concentration and pH. The efficiency of these functionalized nanoparticles for removal of Cu 2+ from water has been explored and showed that adsorption is highly dependent of pH and that it occurs either by forming chelate complexes and/or by electrostatic interaction. The adsorption process, which reaches equilibrium in few minutes and fits a pseudo second-order model, follows the Langmuir adsorption model with a very high maximum adsorp- tion capacity for Cu 2+ of 625 mg/g. Furthermore, these nanoadsorbents can be used as highly efficient separable and reusable materials for removal of toxic metal ions. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Contamination of water with toxic metal ions is becoming a severe environmental and public health problem. Thus, rising demands for clean and safe water in extremely low levels of heavy metal ions make it greatly important to develop improved technologies for heavy metal ions removal. The conventional methods commonly used for the removal of metals from liq- uid effluents, such as precipitation and flocculation, have several disadvantageous features such as expensive equipment require- ment, continuous replenishment of chemicals, time consuming and easy to produce secondary pollution. Alternative methods, as adsorption, present several advantages on the other tech- ∗ Corresponding author. Tel.: +55 61 9206 0946. E-mail addresses: mhsousa@unb.br, mhsqui@gmail.com (M.H. Sousa). niques for water reuse in terms of the initial cost, simplicity of design, ease of operation, low quantity of residues gener- ated, easy recovery of metals and the possibility to reuse the adsorbent [1]. Recent advances suggest that many of the issues involving water quality could be resolved or greatly ameliorated using nanoparticles (NPs), nanofiltration or other products result- ing from the development of nanotechnology [2]. Particularly, nanostructured materials have been investigated due to its high superficial adsorbent area and capability of functionalization with different molecules. Moreover its unique physical and physico- chemical properties (structural, electrical, optical, magnetic, etc.) can provide unprecedented opportunities for the adsorption of heavy metals ions in highly efficient and cost-effective approaches. Advantageously, the manipulability of magnetic nanoparticles by an external magnetic field gradient opens up many applications involving the environmental area [3,4]. However, bare mag- netic nanoparticles present non-specific adsorbent surface, easily 0304-3894/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jhazmat.2013.11.022