Selective adsorption of metallic complex using polyaniline or polypyrrole

The preparation of composites of cellulose acetate, triphenyl phosphate and poly (acrylic acid) (M), coated with polyaniline (M-PAni) or polypyrrole (M-PPy), including tests of the adsorptivity of complexes of copper-iodide, are presented in this work. Characterization of M-PAni and M-PPy by FT-IR and TGA before and after being exposed to natural weathering conditions are done to study the effects that environmental conditions have on them. In solutions with Cu only, the M-PAni presented 51.6% Cu adsorption and M-PPy presented 10.7%. SEM analysis, EDS, XPS and ATR-FTIR of M-PAni and M-PPy before and after of Cu adsorption are included. In the presence of gold-iodide complex, M-PAni shows 47.4% Cu adsorption, six times higher than the M-PPy, 7.2%; this result is attributed to better interaction between the PAni and the copper-iodide complex than PPy and the copper-iodide. The adsorption equilibrium data of copper-iodide complex fits the Langmuir isotherm model for both M-PAni and M-PPy, suggesting the formation of an adsorbed monolayer. Desorption process for Au is more effective in the two materials, 34.1% with M-PAni and 86.6% with M-PPy, than for Cu with 1.0% and 2.6% respectively. The present method, which uses iodide as a single leaching agent for Au and Cu and M-PAni and M-PPy as adsorbents is recommended. These composites are suitable selective materials.