Hydrodesulfurization (HDS) processes are essential to petroleum refining as they remove S-atoms from sulfur-containing molecules from petroleum streams before they can poison precious metal catalysts employed in later steps. The resulting S-atoms are separated from the petroleum streams in H2S, an extremely toxic gas that cannot be released into the environment or conveniently stored as waste. The H2S(g) is oxidized to cyclo-octasulfur (S8), a non-toxic solid that can be readily manipulated under a wide variety of environmental conditions. In this manner, petroleum refineries generate nearly 7 million metric tons of S8 that find no productive use and are discarded in solid-waste storage sites. Elemental sulfur is a remarkably unreactive compound, but at temperatures &gt;160 °C, the cyclo-S8 form ring-opens to generate oligo- and poly-sulfur chains comprising sulfur-radical termini. These radical termini can then react with alkenes to form highly-crosslinked polymers and networks. Research in our group has emphasized alkene-containing carbon feedstocks derived from agricultural wastes. Unsaturated free fatty acids (FFAs) are particularly promising feedstocks given that they are generally discarded as unusable wastes following rendering processes and that they comprise C=C bonds without requiring any additional chemical functionalization. Our findings on FFA/S8 thermoplastics and cements will be presented.

Versatile, valuable materials from waste products of petroleum and agriculture industries

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.