PRODUCING CLEAN BIOMASS SYNGAS VIA CATALTYIC REFORMING FOR FUELS PRODUCTION

摘要

Thermochemical biomass conversion to fuels and chemicals can be achieved through thermochemical gasification to syngas. The biomass-derived raw syngas contains the building blocks of carbon monoxide and hydrogen as well as impurities such as tars, hydrocarbons, and hydrogen sulfide. These impurities must be removed prior to fuel synthesis. We use catalytic reforming to convert tars and hydrocarbons to additional syngas, which increases biomass carbon utilization. In this work, a multi-stage catalyst development approach was employed to evaluate and optimize fluidizable tar reforming catalysts for conditioning oak derived syngas for downstream fuel synthesis. Nickel-based catalysts using a fluidizable support were synthesized and evaluated for reforming performance in two types of pilot scale fluidized tests (circulating and coupled reforming regenerating) conducted with model and biomass derived syngas. Hydrogen sulfide present in raw syngas and added to model syngas impacted reforming performance and required catalyst regeneration. Regeneration processes comprising mixtures of steam and other gases were evaluated and optimized for pilot scale use as both processes are significant components of overall process economics. Multiple characterization techniques (physical and chemical) were used to determine catalyst differences and understand how use impacts reforming and regeneration. The evaluation of these catalysts with model and raw syngas, regenerability, and pre- and post use characterization will be discussed in the context of selecting the best process for pilot scale demonstration.