Jing Zhang

Assessing lignin-derived cycloalkane-rich fuels produced via depolymerization and hydrodeoxygenation as drop-in jet fuels, focusing on process intensification, aviation fuel standards, and environmental and economic sustainability.

Hydrogenolysis has emerged as a promising strategy for the chemical recycling of plastic waste, yet its reliance on high-pressure hydrogen poses significant challenges. Biomass- or CO₂-derived formic acid (FA) is a renewable hydrogen carrier with the advantages of low toxicity and ease of storage and transport. Here, we use FA to replace high-pressure hydrogen to convert polyethylene (PE) into fuels and chemicals with only 4.1% gaseous products by a RuPt alloy catalyst. We demonstrate that the trace amounts of CO generated from the decomposition of FA do not poison the active sites, but rather induce the formation of Ru^δ+, which facilitates the C–C bond cleavage during PE hydrogenolysis. This approach eliminates the need for high-pressure hydrogen and provides a more flexible and adaptable approach for decentralized plastic processing.

Catalytic hydrothermal processing is a promising technology for the production of biofuels used in transportation to alleviate the energy crisis. An important challenge for these processes is the need for an external supply of hydrogen gas to accelerate the deoxygenation of fatty acids or lipids. It follows that in situ-produced hydrogen can improve process economics. This study reports on the use of various alcohol and carboxylic acid amendments as sources for in situ hydrogen production to accelerate Ru/C-catalyzed hydrothermal deoxygenation of stearic acid. Addition of these amendments significantly increases yields of liquid hydrocarbon products, including the major product heptadecane, from stearic acid conversion at subcritical conditions (330 °C, 14-16 MPa during the reaction). This research provided guidance for simplifying the catalytic hydrothermal process of biofuel production, making the production of the desired biofuel in one pot possible without the need for an external H₂ supply.