Polydopamine Nanoparticles as a New and Highly Selective Biosorbent for the Removal of Copper (II) Ions from Aqueous Solutions

• Published in: Water, air, and soil pollution Vol. 223; no. 6; pp. 3535 - 3544
• Main Authors: Farnad, Neda, Farhadi, Khalil, Voelcker, Nicolas H.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-07-2012; Springer; Springer Nature B.V
• Subjects: Adsorbents; Adsorption; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Atoms & subatomic particles; Biopolymers; Bioremediation; Climate Change/Climate Change Impacts; Copper; Copper compounds; Diffraction; Dopamine; Earth and Environmental Science; Entropy; Environment; Environmental monitoring; Experiments; Free energy; Heavy metals; Hydrogeology; Ions; Isotherms; Mathematical models; Nanoparticles; Nanostructure; Oxidation; Pollutants; Scanning electron microscopy; Soil Science & Conservation; Studies; Thermodynamics; Water Quality/Water Pollution; X-ray diffraction; X-rays; Zinc compounds; Nanoparticles; Polydopamine; Adsorption; Copper; Biopolymer
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-012-1131-7

The adsorption and desorption of copper (II) ions from aqueous solutions were investigated using polydopamine (PD) nanoparticles. The nanoscale PD nanoparticles with mean diameter of 75 nm as adsorbent were synthesized from alkaline solution of dopamine and confirmed using scanning electron microscopy and X-ray diffraction analysis. The effects of pH (2–6), adsorbent dosage (0.2–0.8 g L
−1
), temperature (298–323 K), initial concentration (20–100 mg L
−1
), foreign ions (Zn
2+
, Ni
2+
, Cd
2+
, Fe
2+
, and Ag
+
), and contact time (0–360 min) on adsorption of copper ions were investigated through batch experiments. The isotherm adsorption data were well described by the Langmuir isotherm model. The maximum uptake capacity of Cu
2+
ions onto PD nanoparticles was found to 34.4 mg/g. The kinetic data were fitted well to pseudo-second-order model. Moreover, the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy) were studied.