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Catalytic hydrothermal liquefaction (HTL) of cardboard was carried out in a 300 mL Parr batch reactor using 5 wt % Ni­(NO3)2, Ca­(NO3)2, and NiCl2 in a temperature range of 225–300 °C for H2, biocrude, and bio-oil production. A slurry with cardboard to water weight ratio of 1:30, 1:10, 1:4, or 1:1.5 was loaded in the reactor and pressurized with N2 (40 or 200 psi). HTL was performed at various temperatures for 120 min. While HTL was in progress, gas samples were withdrawn periodically and analyzed by GC. The maximum H2 yield of 11.46 mL/g of cardboard was obtained using Ni­(NO3)2 at 300 °C in 30 min. The percent liquefaction of biomass was quantified by TOC. The liquefaction yields were found to be dependent on reaction temperature, residence time, cardboard to water ratio, and operating pressure. The highest biocrude yield of 47.14% was observed at 275 °C in 30 min. Light bio-oil (LBO) and heavy bio-oil (HBO) were extracted by dichloromethane and acetone, respectively, and characterized by GC/MS and elemental analyzer. LBO contained mainly C4–C11 oxygenated hydrocarbons with a higher heating value (HHV) of 27.71 MJ/kg. HBO consisted of C17–C22 oxygenated compounds with a HHV of 29.62 MJ/kg.

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The greater activity of MMP-12 than MMP-3 toward substrates from protein fibrils has been quantified. Why is MMP-12 the more active protease? We looked for behaviors associated with the higher activity of MMP-12 than MMP-3, using nuclear magnetic resonance to monitor backbone dynamics and residue-specific stabilities of their catalytic domain. The proteolytic activities are likely to play important roles in inflammatory diseases of arteries, lungs, joints, and intestines. Nuclear magnetic resonance line broadening indicates that regions surrounding the active sites of both proteases sample conformational substates within milliseconds. The more extensive line broadening in MMP-3 suggests greater sampling of conformational substates, affecting the full length of helix B and beta-strand IV forming the active site, and more remote sites. This could suggest more excursions to functionally incompetent substates. MMP-3 also has enhanced subnanosecond fluctuations in helix A, in the beta-hairpin of strands IV and V, and before and including helix C. Hydrogen exchange protection in the EX2 regime suggests that MMP-3 possesses 2.8 kcal/mol higher folding stability than MMP-12(E219A). The beta-sheet of MMP-3 appears to be stabilized still more. The higher stability of MMP-3 relative to MMP-12 coincides with the former's considerably lower proteolytic activity. This relationship is consistent with the hypothesis that enzymes often trade stability for higher activity.

Short energy intensive hydrothermal liquefaction (HTL) of biomass in the presence of Ni salt catalyst selectively generates H 2 in the product gas and biocrude mainly containing C 1-C 3 acids (formic, lactic, propionic, acetic), HMF and furfural. The H 2 mass balance indicated that only 3.12 vol% H 2 in biomass (cotton) was released as product gas; 48.7 vol% was captured in the C 1-C 3 acids while the remainder H 2 was trapped in oxygenated compounds and char. Continuing HTL after 120 minutes caused no further increase in gas phase H 2 yields. To enhance the H 2 yields with minimal energy input, solar photocatalytic reforming (PR) of the biocrude with Pt/TiO 2 catalyst was investigated. Photocatalysis of activated carbon (AC) treated biocrude generated an additional H 2 , 17.82 wt%. H 2 yields from photoreforming of simulated biocrude acid mixture and actual biocrude were compared. Enhanced H 2 generation was observed with integrated HTL-PR of biomass.