The use of electrolyte redox potential to monitor the Ce(IV)/Ce(III) couple

Abstract

Mathematical modelling of the oxidation reduction redox potential (ORP) of an electrolyte has been carried out for a batch system comprising an electrochemical reactor and an electrolyte circuit containing a redox couple. The ORP can be useful to monitor the environmental impact of chemical species in solution that represent a risk to the environment. Considerations of four fundamental equations, namely, the Nernst equation, a mass balance, Faraday's laws of electrolysis and a first order kinetic equation, leads to an expression for the electrolyte redox potential as a function of the batch time, the electrical charge and the redox concentration. Such an expression facilitates graphical plots which can be used to estimate kinetic parameters, current efficiency and the relative redox concentration. The Ce(IV)/Ce(III) system has been chosen as a model reaction for electrolyte redox potential measurement in a batch recycle system consisting of a pumped flow through a divided FM01-LC parallel-plate electrochemical reactor (64 cm 2 projected electrode area) and a well mixed tank (3600 cm 3 ). The differences between experimental and model predictions are discussed. r

Redox flow batteries: a review

“…Trinidad et al developed an oxidation-reduction-redoxpotential model to monitor the Ce(III)/Ce(IV) couple [177] E e ¼ E …”

Electrochemical redox processes involving soluble cerium species

“…Volumetric determination of Ce(IV) can be performed with excellent results against a standard solution of Fe(II) prepared with ammonium iron(II) sulphate using ferroin as indicator [183]. If Ce(III) analysis is required, it can be easily oxidised to Ce(IV) by treatment with ammonium persulfate in presence of sulfuric acid and silver nitrate as catalyst [183].…”

“…If Ce(III) analysis is required, it can be easily oxidised to Ce(IV) by treatment with ammonium persulfate in presence of sulfuric acid and silver nitrate as catalyst [183]. These methods have been used routinely for the determination of cerium in MSA solutions [68,71].…”

“…These methods have been used routinely for the determination of cerium in MSA solutions [68,71]. Cerium can also be determined by UV spectroscopy [105,173,184], fluorimetry [185], voltamperometry [173], and potentiometric cells [183]. Atomic absorption (AA) and inductively coupled plasma mass spectrometry (ICP) are more appropriate techniques for trace analysis.…”

A Smart Multi-parameter Sensor with Online Monitoring for the Aquaculture in China

“…So, only the detection principles about ion-selective electrodes and other physical electrodes are introduced here. Nernst equation is a mathematical description of an ideal pH or ORP electrode behavior [6][7][8]. It's an important connection between the electric potential difference and the density of the active material in electrochemical system:…”