title: Sono-electrochemical recovery of metal ions from their aqueous solutions.
abstract: Metal recovery from aqueous waste streams is an important goal for recycling, agriculture and mining industries. The development of more effective methods of recovery have been of increasing interest. The most common methods for metal recovery include precipitation, electrochemical, ion exchange, flocculation/coagulation and filtration. In the current work, a sono-electrochemical technique employing sound field at megasonic frequency (500kHz or 1MHz) in conjunction with electrochemistry is evaluated for enhanced recovery of selected metal ions (palladium, lead and gallium) with different redox potentials from their aqueous solutions. The surface morphology and elemental composition of the metal deposits were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The percent recovery was found to depend on the type of metal ion and the megasonic frequency used. Palladium was recovered in its metal form, while lead and gallium were oxidized during or after the recovery process.
authors.affiliation: Department of Materials Science and Engineering, The University of Arizona, 1235 E. James E. Rogers Way, Tucson, AZ 85721, USA.
authors.forename: Bingfeng
authors.initials: B
authors.lastname: Dong
authors.affiliation: Department of Materials Science and Engineering, The University of Arizona, 1235 E. James E. Rogers Way, Tucson, AZ 85721, USA.
authors.forename: Asher
authors.initials: A
authors.lastname: Fishgold
authors.affiliation: Department of Chemistry and Biochemistry, The University of Arizona, 1306 E. University Blvd, Tucson, AZ 85721, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, The University of Arizona, 1235 E. James E. Rogers Way, Tucson, AZ 85721, USA.
authors.forename: Keith
authors.initials: K
authors.lastname: Runge
authors.affiliation: Department of Materials Science and Engineering, The University of Arizona, 1235 E. James E. Rogers Way, Tucson, AZ 85721, USA.
authors.forename: Pierre
authors.initials: P
authors.lastname: Deymier
authors.affiliation: Department of Materials Science and Engineering, The University of Arizona, 1235 E. James E. Rogers Way, Tucson, AZ 85721, USA. Electronic address: manishk@email.arizona.edu.
authors.forename: Manish
authors.initials: M
authors.lastname: Keswani
keywords: Electrochemistry; Megasonic; Metal recovery; Sonochemistry