Parametric study of the cadmium thermoelectrochemical hydrogen cycle

Conference · Wed Dec 31 23:00:00 EST 1980

OSTI ID:6173493

Schreiber, J D; Carty, R H

A parametric study of the flowsheet efficiency of the Institute of Gas Technology (IGT) Hybrid Cadmium Cycle, Reactions 1 through 3, has been performed. (1) Cd(s) + 2H/sub 2/0(l) ..-->.. Cd(OH)/sub 2/(s) + H/sub 2/(g) (electrolysis) (2); Cd(0H)/sub 2/(s) ..-->.. Cd0(s) + H/sub 2/O(g); and (3)d0(s) ..-->.. Cd(g) + 1/2 0/sub 2/(g). All steps of this cycle have been experimentally investigated. Reaction 1 was conducted electrolytically with a sodium chloride electrolyte to produce cadmium chloride in the anode compartment and hydrogen and sodium hydroxide in the cathode compartment. The cadmium chloride and sodium hydroxide solutions are then removed and mixed to form the Cd(0H)/sub 2/ precipitate and NaCl solution. The rate of Reaction 2 has been studied at temperatures between 425 and 675 K. The decomposition of the cadmium oxide, Reaction 3, has been demonstrated using concentrated solar heat in a SERI-sponsored program. The parameters varied in this study of the cycle flowsheet efficiencies were - Electrolytic cell voltage: 0 to 1 V; Temperature of Cd0 decomposition: 300 to 1900 K; and Heat loss due to quenching of the cadmium vapor formed in Reaction 3: 0% and 100%. At a cell potential of 0.2 V, the efficiencies were - No quenching of Cd Vapor: 53.7% to 61.1%; and Total quenching: 37.8% to 42.1% over the temperature range investigated.

• OSTI ID: 6173493
• Report Number(s): CONF-810812-38
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080101* -- Hydrogen-- Production-- Electrolysis
080102 -- Hydrogen-- Production-- Thermochemical Processes
CADMIUM
CADMIUM COMPOUNDS
CADMIUM OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
DIAGRAMS
EFFICIENCY
ELECTROLYSIS
ELEMENTS
FLOWSHEETS
HYDROGEN COMPOUNDS
HYDROGEN PRODUCTION
LYSIS
METALS
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PRODUCTION
THERMOCHEMICAL PROCESSES
WATER