Photoreduction of Pb(II) ions from aqueous solution by titania polyvinylalcohol-alginate beads

Knowing the photocatalytic reduction of heavy metal ions in waters is of interest and putting this to practical options for improving the environment performance. The purpose of this study was to assess effectiveness of the titania polyvinylalcohol-alginate beads (TPVAABs) as photocatalyst in the removal of Pb(II) ions from aqueous solution, compared to the maghemite polyvinylalcohol-alginate beads (MPVAABs). This study performed the tests of photoreduction of Pb(II) ions by both TPVAAB5 and TPVAABs in batch experiments. The results showed that the use of TPVAABs could be effective to remove Pb(II) ions from aqueous solution with 98% efficiency after 135 min of reaction time under sunlight irradiation, compared with 98.3% efficiency for the use of MPVAABs. The desorption of Pb(II) ions for the first cycle of adsorption/desorption appeared to be optimal for the TPVAAB5 recovery. The photocatalytic reduction of Pb(II) ions by TPVAABs can be used repeatedly more than seven cycles of adsorption/desorption. The present study reported photoreduction treatment system to remove Pb(II) ions from aqueous solution by TPVAABs, as well as by MPVAABs, represents a rapid and reliable method to strengthening physicochemical process of treating metal-contaminated wastewater in the future. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.