Experimental study on dynamic release and transformation of sulfur during pyrolysis of Shanxi high-sulfur anthracites based on MFBRA and XPS

Pyrolytic desulfurization of two Shanxi high-sulfur anthracites was investigated experimentally under hydrogen atmospheres using a micro fluidized bed reaction analyzer (MFBRA), the dynamic release behavior of sulfur-containing gas during pyrolysis was characterized by a rapid online gas analyzer, and the transformation between sulfur-containing components in the resultant char was analyzed based on morphological and XPS characterizations. The results show that the dynamic release of sulfur-containing gas features two intensity peaks at 530−560 ℃ and 812−830 ℃, respectively, indicating that the sulfur release proceeds by two subsequent processes: the reduction reaction of pyrite and the organic sulfur decomposition. The migration from inorganic to organic sulfur occurs predominately at lower temperatures, while the transformation between different forms of organic sulfur components is dominant at higher temperatures. Overall, the anthracite coal with a higher organic sulfur content has a higher sulfur removal efficiency in the hydrogen atmosphere. The research results provide the essential data supporting the development of highly efficient pyrolysis desulfurization technology for clean and efficient utilization of high sulfur anthracite coal resources.