Flow Injection Electrochemical Quartz Crystal Microbalance with ICP-OES Detection: Recovery of Silver by Electrodeposition with Redox Replacement in a Flow Cell

Abstract

We developed a new on-line hyphenated flow injection analysis technique (FI-EQCM-ICP-OES) that allows electrochemical deposition and stripping with mass detection and elemental analysis. This technique was used to study a new system for electrochemical recovery of silver from a 0.5 mM Ag+/5 mM Cu2+/0.5 M H2SO4 solution by pulsed electrodeposition with redox replacement (EDRR) in a small flow cell. The metal ions in a 500 μl sample are injected into the sulfuric acid carrier stream and deposited onto an electrochemical quartz crystal microbalance (EQCM) electrode housed in a 50 μl flow cell. The deposits are subsequently stripped off electrochemically in the same cell and analyzed downstream in an ICP-OES. The stripped metal layer was found to be composed of Ag with no detectable Cu for a redox replacement time of 10 s, and 91 wt.% Ag–9 wt.% Cu for a redox replacement time of 5 s. Microscopy measurements demonstrated that the electrode was covered with silver particles, some of which contain Cu in the case of the 5 s replacement time. This technique allowed the study of mass changes on the electrode during electrodeposition and open circuit times in each EDRR cycle in flowing solutions.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 01, 2021
Source ID
10.1149/1945-7111/abfcdd

Entities

People

  • Cornelius F Ivory
  • Daniel E Molina
  • Haluk Beyenal
  • Nathalie A. Wall

Organizations

  • Defense Threat Reduction Agency
  • National Nuclear Security Administration

Tags

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Electrochemical Surface Science
  • Fluid Mechanics and Fluid Dynamics.