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Cobalt molybdenum carbide supported on activated carbon was synthesized and the effect of sulfiding in catalytic activity of the glycerol trioleate deoxygenation process (DOX) was evaluated. Prior to glyceryl trioleate deoxygenation reactions, the catalyst was reduced and sulfided with CS2/H2. CoMo/CA carbide was characterized by specific area (B.E.T), X-ray diffraction (DRX), elemental analysis (CHON-S), potentiometric titration with butylamine and X-ray photoelectron spectroscopy (XPS). The surface area of the CoMo/CA carbide and the support were 246 m2/g and 881 m2/g, respectively. The XRD analysis verified the presence of the Co6Mo6C2 and metallic cobalt. XPS showed the presence at the surface of signals assignable to Mod+, Mo4+, Mo6+, Co2+, S2- and SO4 2-. The sulfided CoMo/CA carbide showed higher glyceryl trioleate deoxygenation activity than the no sulfided CoMo/CA carbide. The highest yield was obtained at 310 °C, 900 psi H2 and 2 h of reaction (conversion to 100%) and a higher selectivity to heptadecane (55%) and octadecane (45%), favoring the decarboxylation (HDCX) and decarbonylation (HDCn) than the hydrodeoxygenation (HDO). [ABSTRACT FROM AUTHOR]

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Ozone exposure from environmental smog has been implicated as a risk factor for developing dry eye disease (DED). The tear film lipid layer (TFLL), which is the outermost layer of the tear film and responsible for surface tension reduction while blinking, is in direct contact with the environment and serves as the first line of defense against external aggressors such as environmental pollution. The impact of exposure to ozone on the biophysical properties of three TFLL model membranes was investigated. These model membranes include a binary mixture of cholesteryl oleate (CO) and L-α-phosphatidylcholine (egg PC), a ternary mixture of CO, glyceryl trioleate (GT) and PC, as well as a quaternary mixture of CO, GT, a mixture of free fatty acids palmitic acid and stearic acid (FFAs) and PC. Biophysical impacts were evaluated as changes to the surface activity, respreadability, morphology and viscoelastic properties of the films. Expansion to higher molecular areas was observed in all the TFLL model membrane films which is attributable to the accommodation of the cleaved chains in the film. Significant morphological changes were observed, namely fluidization and the disruption of the phase transition behaviour of GT, and multilayer formation of CO. This fluidization reduces the hysteresis loops for the model membranes. On the other hand, the viscoelastic properties of the films exhibited differential impacts from ozone exposure as a function of composition. These findings are correlated to chemical changes to the lipids determined using ESI-MS.