Chemical and electrochemical Chromium (VI) recovery process by conducting composite, olive pomace/PANI-HCL.

The aim of this study is the use of a new conducting composite material which was prepared from an agricultural byproduct "olive pomace (OP)" and a polymer "polyaniline doped with a chlorhydric acid (PANI-HCl) and used for the fabrication of electrode, which was then used as substrate for the recovery of chromium hexavalent to an aqueous solution through chemical adsorption and electrosorption tests. We used the spectral analysis techniques such as FT-IR to characterize the material as well as scanning electron microscopy (SEM) to show that the PANI was successfully attached to OP. We carried out adsorption in batch system and electrosorption tests in acid medium within an electrochemical cell at a potential of +800 mV imposed and we compared the recovery with chemical adsorption at open circuit under the same conditions. For batch adsorption tests of Cr (VI) on olive pomace, PANI-HCl and the composites material prepared; the effect of several parameters such as the contact time, and the pH of the solution were studied. For the électrosorption tests, the results demonstrated that the electrosorption capacity of Cr (VI) is superior to the adsorption, which is due to the excellent electrical conductivity and mechanical properties of OP/PANI composite electrode. [ABSTRACT FROM AUTHOR]