Adsorption of Biodegradable Polyelectrolyte onto Cotton for Fixation of Copper and Lead: Comparison to a Cation Exchange Textile

Abstract

In order to develop fibrous materials for treatment of waste water and industrial effluents, cotton and Cation Exchange Textiles (CET) were used as supports. Their modification with the biodegradable positive polyelectrolyte (chitosan) improved performance for the fixation of heavy metals such as copper and lead. The influence of the amine group of chitosan on the anionic sites of textiles has been investigated. The adsorption isotherms were applied according to Freundlich and Langmuir models. No physical damage of the adsorbents was observed after seven cycles of adsorption/desorption using EDTA and HCl as eluents. The cation exchange capacity, pH, adsorption rate, and adsorption kinetics were also studied. The mechanical pathways of Pb(II) and Cu(II) uptake were examined by means of Fourier transform infrared (FTIR). The regeneration of the modified textiles (cotton and CET) with chemical reagents was satisfactory, but much less under the application of an electric field, because of complex phenomenon. Nevertheless, the membrane electroextraction of metal from CET still remains efficient since it obeys the ionic exchange process.

Keywords:

• adsorption
• membrane electroextraction
• metals
• polyelectrolyte
• textiles

Notes

a: 10⁻¹ mol / l.

b: 10⁻² mol / l.