Production of clean hydrogen from methane decomposition over molten NiO‐LiOH catalyst systems supported on CaO: Synergistic effect of molten LiOH on catalyst activity

Abstract

AbstractMature hydrogen producing technologies like steam methane reforming, coal combustion, and hydrogenation of hydrocarbons are leading emitters of greenhouse gases into the atmosphere. Catalytic decomposition of methane into carbon and hydrogen is a sure way of controlling the net emission of this greenhouse gas into the atmosphere. In this study, we present an environmentally benign approach of producing hydrogen from methane over a supported molten metal oxide catalyst. Catalyst systems were prepared by incipient wetness impregnation and characterized for crystallinity, shape and size, and surface area using various techniques. Methane conversion experiments were done in a packed bed reactor over three different catalyst systems synthesized from nickel oxide, lithium hydroxide, and calcium oxide (CaO) under various process conditions. Gaseous products from the reactor were analyzed using gas chromatography. Using catalyst 38N12L, 45.9% hydrogen yield was obtained at 650°C and GHSV of 1.2 Lg−1cath−1. The molten environment provided by LiOH enhanced hydrogen yields by 12.6% through surface reaction and chemisorption. Calcium oxide played a bifunctional role as a catalyst support and an adsorbent of in situ generated CO/CO2 gases thereby improving hydrogen quality.