Novel High Performance Catalyst for Complete and Energy Efficient Tar Reforming in Biomass Derived Syngas

Abstract

In hot gas cleaning of biomass gasification gas conversion results of a fixed bed MgO-NiO catalyst tested in a simulated biomass gasification gas at a naphthalene inlet content of 5 g / Nm³ in the presence of 100 ppmv H₂S have shown so far, that catalytic filtration is feasible, if a temperature of 800°C and a space velocity of 3054 or 3207 h^-1, respectively, is applied by integrating the catalyst in the cylindrical hollow space of a hot gas filter candle. In this work a novel patented tar reforming catalyst C&CS #1050 B is presented that exhibits a distinctly superior catalytic performance in direct comparison at a total model tar content of 13 g / Nm³. Complete conversion at a space velocity of 6000 h^-1 from 750°C down to 650°C was measured because of its more than 4-fold higher NiO density in a fixed bed compared to the MgO-NiO catalyst and its approx. 3.5 – 4.5 times higher BET surface area compared to typical commercial steam reforming catalysts. Due to its 21-fold higher NiO density compared to a catalyst integrated in a filter candle as catalytic layer, fixed bed based catalytic filter candles are superior to candles of catalytic layer design. Based on the evidence of 99% model tar conversion at 750°C also at a content of 4.9 g / Nm³ naphthalene and 9.3 g / Nm³ toluene of a C&CS #1050 B filled candle of 60 mm outer diameter complete real tar abatement with a capacity of 13 g / Nm³ is estimated at this temperature allowing a more energy-efficient hot gas filtration and enlarging the applicability of catalytic hot gas filters to higher tar inlet contents.