Hydrogen Generation in an Annular Micro-Reactor: an Experimental Investigation of Water Splitting Reaction Using Aluminum in Presence of Potassium Hydroxide

Abstract

Abstract Hydrogen is one of the important non-conventional energy sources because of its high energy content and non-polluting nature of combustions. The water splitting reaction is one of the significant methods for hydrogen generation from non-fossil feeds. In the present paper, the hydrogen generation has been experimentally investigated with water splitting reaction using metal aluminum in presence of potassium hydroxide as an activator under flow conditions. The rate of hydrogen generation was reported in the annular micro- reactor of 1 mm annulus using various flow rates of aqueous 0.5 N KOH ranging from 1 ml/min to 10 ml/min. The complete conversion of aluminum was observed at all the flow rates of aqueous KOH. The hydrogen generation rate was observed to depend on the flow rate of liquid reactant flowing through the reactor. At 1 ml/min of 0.5 N KOH, hydrogen generates at an average rate of 3.36 ml/min which increases to 10.70 ml/min at 10 ml/min of aqueous KOH. The Shrinking Core Model was modified for predicting the controlling mechanism. The rate of hydrogen generation was observed to follow different controlling mechanisms on various time intervals at low flow rates of aqueous KOH. It was observed that chemical reaction controls the overall rate of hydrogen generation at higher flow rates of aqueous KOH.