Titanium Dioxide/Activated Carbon Electrode with Polyurethane Binder for the Removal of Indium Ions via Capacitive Deionization

Abstract

The process of removing indium ions from aqueous solutions by applying capacitive deionization (CDI) is reported in this manuscript. First, a modified carbon material was prepared by incorporating titanium dioxide (TiO2) into activated carbon (AC). A microwave-assisted ionothermal synthesis (MAIS) method was used to produce evenly distributed nanostructured anatase TiO2 on the surface of AC. A polyurethane (PU) elastomer was then synthesized as the binder material instead of using conventional polyvinylidene fluoride (PVDF). By combining the aforementioned materials, a MAIS TiO2/AC-PU electrode was synthesized and applied to CDI tests. Scanning electron microscopy (SEM) was used to characterize the size and dispersion of the composites. For electrochemical properties, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to analyze the synthesized electrode. The performance of the prepared electrode during the CDI process was tested in different concentrations of indium solutions. It was discovered that the indium removal efficiency can be as high as 84% in 1 and 5 ppm of indium solutions.

Using a Simple Magnetic Adsorbent for the Preconcentration and Determination of Ga(III) and In(III) by Electrothermal Atomic Absorption Spectrometry

“…On the other hand, since demand for them is very high, the need to recover these elements from manufactured products at the end of their useful life is becoming more and more evident. In this sense, some processes have recently been proposed for the recovery of indium by pre-leaching in HNO 3 + HF using a new adsorbent material consisting of mesoporous activated carbon [ 5 ] or an electrode with titanium dioxide and activated carbon [ 6 ]. In both cases, the recovery is close to 85%.…”