Kinetic and electrochemical analyses of a CuCI/HCl electrolyzer

Abstract

Summary An electrochemical analysis is carried out from a kinetic electrochemistry perspective of a CuCl/HCl electrolysis cell, within the CuCl thermochemical water splitting process for hydrogen production. The anolyte is a solution of 2 mol L−1 CuCl(aq) and 10 mol L−1 HCl(aq) while the catholyte solution is 11 mol L−1 HCl(aq). The cell current density of 0.5 A cm−2 and voltage of 0.7 V are the desired working conditions for a CuCl/HCl electrolyzer. The current density of 0.5 A cm−2 is assumed to occur at a 5% anolyte conversion degree. At 25°C, the activation overpotential of the anode half‐reaction is found to be 53 mV for a current density of 0.5 A cm−2 while the activation overpotential of the cathode half‐reaction for the same condition is 87 mV. An increase in working temperature decreases the overpotential of the anode half‐reaction and increases the cathode half‐reaction activation overpotential. The ohmic overpotential of the cell membrane is almost 1000 times smaller than that of the activation overpotentials of the electrode half‐reactions for the same temperature and current density. A higher working temperature results in a lower membrane ohmic overpotential. The required voltage to trigger electrolysis for a current density of 0.5 A cm−2 is found to be 0.53 V at 25°C and 0.59 V at 80°C and a higher temperature results in a higher electrochemical efficiency. The cell electrochemical efficiency increases linearly with working temperature while the voltage efficiency peaks at 75% at 60°C.

NiFeCo oxide as an efficient and sustainable catalyst for the oxygen evolution reaction

“…Hydrogen possesses outstanding properties as an energy source, such as carbon neutrality, high efficiency, and nontoxic to environment . Electrocatalysis is an important emerging technology, because it is an inexpensive, clean, and environmentally friendly source of hydrogen energy . It is a simple process by which the strong bonds in water are broken to yield oxygen and hydrogen.…”

“…1 Electrocatalysis is an important emerging technology, because it is an inexpensive, clean, and environmentally friendly source of hydrogen energy. [2][3][4][5] It is a simple process by which the strong bonds in water are broken to yield oxygen and hydrogen. Two chemical reactions occur during electrocatalysis, the oxygen evolution reaction (OER), and the hydrogen evolution reaction (HER).…”

Enhancing stability region of time‐delayed smart power grids by non‐integer controllers

“…When energy is needed, the stored hydrogen is converted into electrical energy by FCs. 2,29,30 The FC and ES, which are other elements of the primary frequency control, are represented by a first-order transfer function in reference to the operation of a battery energy storage facility as shown in Ref. 27 The transfer function G FC (s) of the FC and the transfer function G ES (s) of the ES are shown in Equation 3.…”

“…When wind and solar energy production is high, hydrogen is produced by ES and stored in hydrogen tank. When energy is needed, the stored hydrogen is converted into electrical energy by FCs 2,29,30 . The FC and ES, which are other elements of the primary frequency control, are represented by a first‐order transfer function in reference to the operation of a battery energy storage facility as shown in Ref 27 .…”

A review of alkaline solid polymer membrane in the application of AEM electrolyzer: Materials and characterization

“…Besides, without any delay in fuel processing, hydrogen can be generated directly via the electrolyzer unit. It can be placed anywhere, not like a solar cell requiring areas of high sunlight intensity 21,22 . In addition, an electrolyzer unit can be integrated with another power source system in various applications such as stationary, portable, and transportation to provide reliable energy supplies over a long period.…”