Design and Setup Activities for the Development of Methane Autothermal Reforming in a Jet Fountain Fluidized Bed Reactor

Abstract

In the framework of hydrogen production and process intensification for energy applications, this work presents the design and the construction of a novel lab-scale experimental facility, which is aimed at testing and demonstrating the feasibility of the auto-thermal catalytic reforming of methane in a recently proposed reactor configuration, i.e., the jetting fountain fluidized bed (JFFBR). The proposed solution consists of a jet pipe and an annulus which are concentrical and it is designed to operate the auto-thermal reforming in two almost-distinct zones: oxidant (oxygen or air) is only fed to the jet pipe, which substantially provides methane partial oxidation and consequently heat generation; the annulus is designed to operate in a bubbling fluidized bed regime, and it is the region in which methane steam reforming essentially occurs. The two zones communicate through a pair of holes in the bottom part of the jet pipe, which determine the entrainment of solid particles and the fountain on the top of the jet pipe. The jetting fountain fluidized bed regime is expected to enhance the heat and mass transfer phenomena, while the selective fed of the oxidant to the jet pipe is expected to provide an in-situ regeneration of the catalyst. In view of starting an actual experimental program with the designed facility, a suitable catalyst has been selected and its catalytic activity has been characterized in a lab-scale fixed-bed reactor. The formulation, previously optimized, involves a ceria-silica support, which can be easily fluidized, and two active phases, namely Ni and Pt, obtaining a final catalyst 3%Pt-10%Ni/CeO2/SiO2.The catalyst performed well in terms of activity and selectivity. The activity test results from the fixed-bed reactor allowed to set-up a satisfactory kinetic model of the reacting system.