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Conversion of organosolv lignins isolated with and without an inorganic acid catalyst (H2SO4) from hard- and softwood (birch and spruce) into bio-oil through hydrothermal liquefaction has been investigated. Furthermore, fractions of the isolated bio-oils were catalytically deoxygenated to improve the bio-oil properties. As elucidated through NMR, both biomass source and extraction mode influence the bio-oil product distribution. Depending on whether the lignins carry a high content of native structures, or are depolymerized and subsequently condensed in the presence of sugar dehydration products, will dictate heavy oil (HO) and light oil (LO) distribution, and skew the HO product composition, which again will influence the requirements upon catalytical deoxygenation., Validerad;2023;Nivå 2;2023-11-14 (marisr);Funder: European Regional Development Fund (FEDER); general council of Moselle, Region Grand Est, Metz Metropole; University of Lorraine (RESEX project);License fulltext: CC BY, Upgrading of organosolv lignin to jet fuel (GOLdJET FUEL), Eco-efficient biorefinery for competitive production of green renewable shipping fuels (ECO-FORCE FUELS)

Secondary ion mass spectrometry (SIMS), in which energetic ions are implemented to interrogate the surface, is an efficient technique for the molecular analysis and imaging of solid surfaces. Improving the yield of secondary ions remains a challenge in SIMS. Metal-Assisted SIMS (MetA SIMS), where a small quantity of metal (Au, Ag, Pt…) is condensed on the sample surface, was one among the proposed ways to increase the yield using keV monatomic projectiles. In this thesis, the yield enhancements obtained upon 12 keV Ga+, 30 keV Bin+ (n =1,3,5) and 6MeV O3+ bombardment on metal deposited organic materials are investigated. The MeV bombardment results show that the maximum enhancement is achieved only for the thinnest gold films (0.5-2nm), whereas with keV projectiles, the observed enhancement is present for much thicker films (up to 8nm). Following from the studies in Metal Assisted Secondary Ion Mass Spectrometry (MetA SIMS), gold nanoparticles condensed on the surface of organic materials were used as an alternative to the matrix-assisted laser desorption ionization (MALDI). Herein, the influence of a thin layer of gold (1-15 nm) condensed on the surface of a series of pure organic materials, without the use of a MALDI matrix, in the laser ablation using a 355 nm wavelength light has been investigated. For all the investigated materials, the largest signals of characteristic ions are measured after metallization with 4-8 nm of gold. The observed effects can be tentatively explained by the increased laser absorption by the gold nanoparticles in this wavelength range and, as suggested by surface potential measurements, by an increase of the ionization probability. The results suggest that metal-assisted LDI provides an interesting alternative to MALDI for the surface analysis and, potentially, imaging of certain classes of materials, when a minimal perturbation of the surface structure is desired., (FSA 3) -- UCL, 2012

Heteroleptic triphenylphosphine carbonyl palladium clusters of different nuclearities were prepared under mild conditions by only varying the amount of ligand (PPh(3)) used in the synthesis: three different clusters were successfully isolated after CO bubbling in a solution of [Pd(2)(dba)(3)] (dba = dibenzylideneacetone) with 3, 1 or 0.5 equiv of PPh(3), which led, respectively, to [Pd(4)(CO)(5)(PPh(3))(4)] (1), [Pd(10)(CO)(12)(PPh(3))(6)] (2) and [Pd(n)(CO)(x)(PPh(3))(y)] (3) (n approximate to 24). The molecular structures of compounds 1 and 2 were determined by X-ray crystallography. The metal cores in these compounds were shown to consist in a butterfly for 1 and a bridged octahedron for 2. Compound 3 was shown to be at the boundary between molecular clusters and colloidal particles with tentative formulation arising from characterization data. These three clusters and the known [Pd(10)(CO)(12)(PBu(3))(6)] and [Pd(12)(CO)(15)(PBu(3))(7)] were submitted to NaBH(4) reduction. The Pd(4) cluster 1 did not react. The colloidal Pd(n) species led to no isolable product. By contrast, the two Pd(10) and the Pd(12) clusters led to reduction products, isolated as NEt(4)(+) salts. In the case of the reduced Pd(12) cluster, its structure was resolved by X-ray crystallography: the metal core consists of a face-capped octahedron. The reduced species reacted readily with Au(PPh(3))(+), confirming their anionic nature. (C) 2011 Elsevier B. V. All rights reserved.