Kinetics of non-premixed hydrogen-oxygen catalytic recombination reaction at ambient temperature

This study proposes the use of the hydrogen-oxygen catalytic recombination reaction to safely eliminate the leaked hydrogen in a confined environment. Experiments on the hydrogen-oxygen reaction catalyzed by using Pt/C as a catalyst are conducted at ambient temperature in a small cylindrical vessel. The macroscopic kinetic process of the hydrogen-oxygen recombination reaction is investigated, and the effects of the reaction parame-ters, such as the initial hydrogen volume fraction and catalyst layer position, on the re-action temperature and hydrogen conversion are examined. The reaction temperature and temperature rise rate are shown to reach the maximum values when the initial hydrogen fraction is 70 vol%. When the initial hydrogen fraction is < 67 vol%, the hydrogen con-version reaches 100%. After the initial hydrogen fraction is > 67 vol%, the hydrogen con-version decreases significantly, and the hydrogen conversion is only 53% for the initial hydrogen fraction is up to 80 vol%. Moreover, the position of the catalyst layer has a sig-nificant effect on the reaction rate and heat distribution inside the vessel. When the catalyst layer is near the bottom of the reaction vessel, the reaction rate is accelerated and the released heat accumulates at the bottom of the vessel. The influence law of the aforementioned factors can provide a technical reference for applications of the hydrogen-oxygen catalytic reaction.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.