January 1, 2010.
The potential of biomass-derived transportation fuel via thermochemical conversion has been widely recognized due to its renewable and carbon-neutral characteristics. A notable limitation affecting the economic feasibility of thermochemically produced biofuels is the production of unwanted byproducts, including organic tar and inorganic gas constituents (such as sulfur, chlorine, and alkali metals). This investigation focuses on understanding inorganic sulfur contaminants by studying the content and speciation of sulfur in biochar. Various biochar samples were characterized using TruSpec Sulfur Analysis (S-Analysis) and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS). EDS X-ray mapping was used to study the speciation of sulfur in biochar. It was found that biochar from corn stover pyrolysis contains higher concentrations of sulfur than oak. It was also found that in biochar from corn stover pyrolysis, sulfur associates with potassium. Further investigation of sulfur speciation in biochar will help support the purposeful development of strategies to reduce the amount of undesirable sulfur in thermochemically derived biofuels.
National Renewable Energy Laboratory (NREL)