Experimental investigation of fluidized-bed reactor performance for oxidative coupling of methane

Performance of the oxidative coupling of methane in fluidized-bed reactor was experimentally investigated using Mn-Na₂WO₄/SiO₂, La₂O₃/CaO and La₂O₃-SrO/CaO catalysts. These catalysts were found to be stable, especially Mn-Na₂WO₄/SiO₂ catalyst. The effect of sodium content of this catalyst was analyzed and the challenge of catalyst agglomeration was addressed using proper catalyst composition of 2%Mn-2.2%Na₂WO₄/SiO₂. For other two catalysts, the effect of Lanthanum-Strontium content was analyzed and 10%La₂O₃–20%SrO/CaO catalyst was found to provide higher ethylene yield than La₂O₃/CaO catalyst. Furthermore, the effect of operating parameters such as temperature and methane to oxygen ratio were also reviewed. The highest ethylene and ethane (C₂) yield was achieved with the lowest methane to oxygen ratio around 2. 40.5% selectivity to ethylene and ethane and 41% methane conversion were achieved over La₂O₃-SrO/CaO catalyst while over Mn-Na₂WO₄/SiO₂ catalyst, 40% and 48% were recorded, respectively. Moreover, the consecutive effects of nitrogen dilution, ethylene to ethane production ratio and other performance indicators on the down-stream process units were qualitatively discussed and Mn-Na₂WO₄/SiO₂ catalyst showed a better performance in the reactor and process scale analysis.