Two-step thermochemical cycles for hydrogen production using NiFe 2 O 4 /m-ZrO 2 and CeO 2 devices

Two-stepthermochemicalcycleusingferrite-oxide(Fe2O4)devicewasinvestigated.TheH2O(g)wasconverted into H2 in thefirstexperimentwhich wasperformed using a dish typesolarthermalsystem.Howeverthe experimentwaslastedonlyfor2cyclesbecausethemetaloxidedevicewassinteredandbrokendown.Another problem wasthatthereactionwastakenplacemainlyonasideofthemetaloxidedevice.Them-ZrO2,which waswidelyknownasamaterialpreventingsintering,wasappliedonthemetaloxidedevice.Theferriteloading rateandthethicknessofthemetaloxidedevicewereincreasedfrom 10.67wt% to20wt% andfrom 10mm to15mm, respectively.Thechemicalreactorhavingtwoinletswasdesignedinordertosupplythereactantsuniformlyto themetaloxidedevice.Thesecond-experimentwaslastedfor5cycles,whichwasfor6hours.Thetotalamount oftheH2 productionwas861.30ml.Andcerium oxide(CeO2)devicewasusedforincreasingH2 productionrate. CeO2 devicehadlow thermalresistance,however,moreH2 productionratethanFe2O4 device.