Electrochemical hydrogen pumping

Electrochemical pumps and compressors that is, devices for dosage, separation, compression or removal of oxygen (or hydrogen), according to Faraday s law. The set-up devoted to separate oxygen from air has been also referred to as either the ion transport membrane (ITM) or solid electrolyte oxygen separation (SEOS) [6]. 

Qnda, K., Araki, T., Ichihara, K., Nagahama, M. (2009). Treatment of low concentration hydrogen by electrochemical pump or proton exchange membrane fuel cell. Journal of Power Sources, 788(1), 1—7. 

C3H6, H2O Pd/SCY/Pd H" 4-fold increase in the rate of propane decomposition. During the electrochemical pumping of hydrogen, the rate of hydrogen pumped to the outer chamber over I/2F reaches values up to 0.9 [24]... 

Fig. 24.2 Polarization curves (scan rate 1.4 mA s ) of an electrochemical pump operating on pure hydrogen at 160 °C, constant flow rate 94 mL min . Reproduced from [9] with permission of Elsevier...

Figure 11.3 Schematic of an electrochemical pump with a palladium membrane for hydrogen purification.

A hydrogen pump is an electrochemical cell of a proton conductor in which hydrogen in the anode compartment can be electrochemically pumped to the cathode by sending a direct current. Experiments of hydrogen pumps were conducted with the following gas atmospheres. 

If hydrogen is supplied to the cell in excess of that required for the reaction stoichiometry, this excess will leave the fuel cell unused. In case of pure hydrogen, this excess may be recirculated back into the stack so it does not change the fuel cell efficiency (not accounting for the power needed for hydrogen recirculation pump), but if hydrogen is not pure (such as in reformate gas feed), unused hydrogen leaves the fuel cell and does not participate in the electrochemical reaction. The fuel cell efficiency is then ... 

A Perkin-Elmer 5000 AAS was used, with an electrically heated quartz tube atomizer. The electrolyte is continuously conveyed by peristaltic pump. The sample solution is introduced into the loop and transported to the electrochemical cell. A constant current is applied to the electrolytic cell. The gaseous reaction products, hydrides and hydrogen, fonued at the cathode, are flowed out of the cell with the carrier stream of argon and separated from the solution in a gas-liquid separator. The hydrides are transported to an electrically heated quartz tube with argon and determined under operating conditions for hydride fonuing elements by AAS. 

The schematic of the electrolyser system is shown in Figure 1. A 5-cm2 PEM fuel cell hardware (Electrochem Inc.) was employed as an electrolytic cell. To perform electrolysis, the aqueous solution of CuCl (0.2 M) mixed with aqueous HC1 (2 M) was supplied from Reservoir 1 to the anode of the electrolyser via Pump 1. The aqueous HC1 solution (2 M) was supplied from Reservoir 2 to the cathode of the electrolyser via Pump 2. The hydrogen-producing electrolysis reaction was driven by an external applied voltage in the range 0.35-0.9 V. 

Hydrogen pumps — are electrochemical devices with proton-conducting - solid electrolytes, where hydrogen is transported through a dense electrolyte membrane by an applied electrical field. The device... 

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