Cadmium-109 Radioisotope Adsorption onto Polypyrrole Coated Sawdust of Dryobalanops aromatic: Kinetics and Adsorption Isotherms Modelling

PLoS One. 2016 Oct 5;11(10):e0164119. doi: 10.1371/journal.pone.0164119. eCollection 2016.

Abstract

A radiotracer study was conducted to investigate the removal characteristics of cadmium (109Cd) from aqueous solution by polypyrrole/ sawdust composite. Several factors such as solution pH, sorbent dosage, initial concentration, contact time, temperature and interfering metal ions were found to have influence on the adsorption process. The kinetics of adsorption was relatively fast, reaching equilibrium within 3 hours. A lowering of the solution pH reduced the removal efficiency from 99.3 to ~ 46.7% and an ambient temperature of 25°C was found to be optimum for maximum adsorption. The presence of sodium and potassium ions inhibited 109Cd removal from its aqueous solution. The experimental data for 109Cd adsorption showed a very good agreement with the Langmuir isotherm and a pseudo-first order kinetic model. The surface condition of the adsorbent before and after cadmium loading was investigated using BET, FESEM and FTIR. Considering the low cost of the precursor's materials and the toxicity of 109Cd radioactive metal, polypyrrole synthesized on the sawdust of Dryobalanops aromatic could be used as an efficient adsorbent for the removal of 109Cd radioisotope from radionuclide-containing effluents.

MeSH terms

  • Adsorption
  • Cadmium Radioisotopes / isolation & purification*
  • Dipterocarpaceae / chemistry*
  • Hydrogen-Ion Concentration
  • Kinetics
  • Polymers / chemistry*
  • Pyrroles / chemistry*
  • Temperature
  • Water Pollutants, Chemical / isolation & purification*

Substances

  • Cadmium Radioisotopes
  • Polymers
  • Pyrroles
  • Water Pollutants, Chemical
  • polypyrrole

Grants and funding

This work was supported by the University of Malaya Research grant (Grant No PG027A–2014). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.