Hydrogen production by the Cu-Cl thermochemical cycle: Investigation of the key step of hydrolysing CuCl sub(2 to Cu) sub(2)OCl sub(2 and HCl using a spray reactor)

• Published in: International journal of hydrogen energy 2010-02, Vol.35 (3), p.992-1000
• Main Authors: Ferrandon, Magali S, Lewis, Michele A, Tatterson, David F, Gross, Adam, Doizi, Denis, Croize, L, Dauvois, V, Roujou, J L, Zanella, Y, Carles, P
• Format: Article
• Language: English
• Subjects: Atomizers; Copper; Hydrolysis; Nozzles; Reactors; Spectrometry; Sprayers; Sprays
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2009.09.086

One of the most challenging steps in the thermochemical Cu-Cl cycle for the production of hydrogen is the hydrolysis of CuCl sub(2 into Cu) sub(2)OCl sub(2 and HCl while avoiding the need for excess water and the undesired thermolysis reaction, which gives CuCl and Cl) sub(2). Argonne National Laboratory has designed a spray reactor where an aqueous solution of CuCl sub(2 is atomized into a heated zone, into which steam/Ar are injected in co- or counter-current flow. The solid products of the reaction were analyzed by XRD and SEM. With a pneumatic nebulizer, the counter-current flow design gave high yields of Cu) sub(2)OCl sub(2 compared to the co-current flow design, but some CuCl) sub(2) remained unreacted in both designs. With an ultrasonic nozzle, essentially 100% yields of Cu sub(2OCl) sub(2) were obtained. Some CuCl was present in the products with both types of atomizers but this is believed to be due to decomposition of Cu sub(2OCl) sub(2) rather than CuCl sub(2. Analyses of gaseous products from the hydrolysis reactions in a fixed bed were conducted at the Commissariat a L'Energie Atomique using ultraviolet-visible spectrometry and conductivity. At a reaction temperature of 390 degree C, the desired HCl was formed while no Cl) sub(2) was detected until the bed temperature was above 400 degree C.