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Mono and bimetallic platinum-ruthenium nanoparticles have been generated on N-doped graphene (NH-rGO) following an organometallic approach. Surface and structural studies confirmed the formation of bimetallic MNPs with controlled metal compositions. To evaluate the activity/selectivity of the different materials prepared we used the hydrogenation of acetophenone as a model reaction. We found that both the activity and selectivity of the supported-bimetallic NPs are highly dependent on the support and the atomic composition. The higher the Pt/Ru ratio, the higher the selectivity towards 1-phenylethanol. Indeed, a remarkable activity and selectivity in the hydrogenation of acetophenone was observed for PtRu@NH-rGO. The reactivity of these catalysts was also investigated in the hydrogenation of other substrates such as functionalized arenes (i.e.nitrobenzene and benzaldehyde) or hydroxymethylfurfural (HMF), demonstrating that it is possible to control the activity and selectivity of bimetallic Pt-Ru MNPs supported on N-doped graphene by adjusting their metal composition.

This is the peer reviewed version of the following article: Y. Mathieu, J. D. Vidal, L. Arribas Martínez, N. Abad Fernández, S. Iborra, A. Corma, ChemSusChem 2020, 13, 4743, which has been published in final form at https://doi.org/10.1002/cssc.202001295. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving., [EN] During oxidative depolymn. of lignin in aq. alk. medium using mol. oxygen as oxidant, the highly functionalized primary phenolic monomers are not stable products, owing to various not fully identified secondary reaction mechanisms. However, better understanding of the mechanisms responsible for the instability of the main part of the products of interest derived from lignin is of much interest. Evaluation of their individual reactivities under oxidative conditions should significantly help to find a better way to valorize the lignin polymer and to maximize the yields of target value-added products. Consequently, the main objective of this study is to assess the individual stabilities of some selected ligninbased phenolic compds., such as vanillin, vanillic acid, and acetovanillone, together with some other pure chem. compds. such as phenol and anisole to give an insight into the mechanisms responsible for the simultaneous formation and repolymn. of those products and the influence of the oxidn. conditions. Various complementary strategies of stabilization are proposed, discussed, and applied for the oxidative depolymn. reactions of a tech. lignin extd. from pinewood with a high content of b-O-4 interconnecting bonds to try to obtain enhanced yields of value-added products.

[EN] A biocrude was obtained via the catalytic hydrothermal treatment of lignocellulosic biomass. This was further co-hydroprocessed with Straight Run Gas Oil (SRGO) under desulphurization conditions. Amounts of biocrude of up to 20 wt% could be co-processed, while maintaining a diesel stream density within the specifications contained in the road diesel regulation EN 590. The changes in the diesel properties associated with an increasing amount of biocrude were not a simple linear function of biocrude content. Rather, some positive correlations seem to exist between biocrude and SRGO at low biocrude contents, possibly due to intramolecular hydrogen transfer, yielding a diesel stream with a better quality than would be obtained from simply mixing hydrotreated pure streams in a 80% to 20% ratio.

[EN] The direct cracking of crude oil is an interesting option for producing cheaply large amounts of petrochemicals. This may be carried out with catalyst and equipment similar to that of catalytic cracking, but at a temperature range between that of standard catalytic cracking and steam cracking. Thermal cracking will play a role in the conversion, but is rarely disclosed in experimental or modeling work. Thus, a crude oil and its fractions were thermally cracked and the products yields were modeled using a 9 lumps cracking scheme. It was found that heavy fraction cracks twice as fast as diesel fraction and ten times faster than gasoline fraction, with activation energies in the 140-200 kJ/mol range. Selectivity to ethylene, propylene and butenes were found similar in the operating range explored.

[EN] An extra-heavy crude oil was treated at a short contact time in the 510-580 degrees C temperature range in a FCC-like process, first thermally and then in the presence of a solid with low catalytic activity. The treatment greatly improved the properties of the crude oil, reducing the density and viscosity to values that make the oil transportable without dilution in a pipeline. In addition, the upgraded oil was substantially free of contaminants such as metals and heptane insolubles. The use of the solid allowed upgrading all properties with a minimum coke penalty. The residual fraction of the upgraded oil had to be eliminated to obtain a syncrude stable in asphaltene proof, which could be obtained by recycling to extinction in a cracking reactor.

[EN] Wood chips were hydrothermally treated in near critical point water in the presence of a catalyst to yield a raw biocrude, containing a wide range of organic components. This product was subsequently distilled to remove its heaviest fraction, which tends to yield chary products if heated above 350 degrees C. The biocrude obtained has an oxygen content of 12wt% and was subsequently hydrotreated to obtain a hydrocarbon stream. Varying the hydrotreatment operating conditions and catalyst yielded a deoxygenated syncrude which quality improved with operation severity. The hydroprocessed stream produced under very mild conditions can be further upgraded in conventional refinery operations while the stream produced after more severe hydrotreatment can be mixed with conventional diesel. This proof of concept was demonstrated with commercial hydrotreating catalysts, operating between 350 and 380 degrees C, 40 to 120bar pressure and 0.5 to 1h(-1) contact time.

[EN] An unconventional crude from biomass (biocrude) has been processed to yield a hydrocarbon stream that is not only fully processable in conventional refineries but is already close to the specification of commercial fuels such as transportation diesel. The upgrading of biocrude was carried out with a combination of hydrotreatment and catalytic cracking, yielding middle distillate as the main product.

[EN] The possibility to fulfill the increasing market demand and producers' needs in processing crude oil, a cheap and universally available feedstock, to produce petrochemicals appears to be a very attractive strategy. Indeed, many petrochemicals are produced as side streams during crude oil refining, which primary goal remains transportation fuel production. Availability of some critical feedstocks may then depend on local refining policy. In order to improve flexibility, it has been proposed to directly crack crude oil to produce petrochemicals, in particular light olefins (ethylene, propylene, butenes), using technologies derived from fluid catalytic cracking. This paper attempts to review the main research works done on the topic in the literature in the last five decades, focussing on process as well as catalyst technology, with a special interest for fluid catalytic cracking (FCC) based technology that can be used towards maximizing chemicals from crude oil. Factors investigated include use of severe cracking conditions, on-purpose additives (from ZSM5 to more exotic, metal doped additives), recycle streams and multiple riser systems.

The possibility to fulfill the increasing market demand and producers' needs in processing crude oil, a cheap and universally available feedstock, to produce petrochemicals appears to be a very attractive strategy. Indeed, many petrochemicals are produced as side streams during crude oil refining, which primary goal remains transportation fuel production. Availability of some critical feedstocks may then depend on local refining policy. In order to improve flexibility, it has been proposed to directly crack crude oil to produce petrochemicals, in particular light olefins (ethylene, propylene, butenes), using technologies derived from fluid catalytic cracking. This paper attempts to review the main research works done on the topic in the literature in the last five decades, focussing on process as well as catalyst technology, with a special interest for fluid catalytic cracking (FCC) based technology that can be used towards maximizing chemicals from crude oil. Factors investigated include use of severe cracking conditions, on-purpose additives (from ZSM5 to more exotic, metal doped additives), recycle streams and multiple riser systems.

Precipitated kraft lignin from black liquor was converted into green diesel in three steps. A mild Ni-catalyzed transfer hydrogenation/hydrogenolysis using 2-propanol generated a lignin residue in which the ethers, carbonyls, and olefins were reduced. An organocatalyzed esterification of the lignin residue with an insitu prepared tall oil fatty acid anhydride gave an esterified lignin residue that was soluble in light gas oil. The esterified lignin residue was coprocessed with light gas oil in a continous hydrotreater to produce a green diesel. This approach will enable the development of new techniques to process commercial lignin in existing oil refinery infrastructures to standardized transportation fuels in the future.

Precipitated kraft lignin from black liquor was converted into green diesel in three steps. A mild Ni-catalyzed transfer hydrogenation/hydrogenolysis using 2-propanol generated a lignin residue in which the ethers, carbonyls, and olefins were reduced. An organocatalyzed esterification of the lignin residue with an insitu prepared tall oil fatty acid anhydride gave an esterified lignin residue that was soluble in light gas oil. The esterified lignin residue was coprocessed with light gas oil in a continous hydrotreater to produce a green diesel. This approach will enable the development of new techniques to process commercial lignin in existing oil refinery infrastructures to standardized transportation fuels in the future.

The single and combined effects on catalyst stability, activity and selectivity of iron and calcium metal organic contaminants deposited on a fluidized catalytic cracking (FCC) catalyst via a cyclic deactivation treatment have been studied. It has been found that iron contamination decreases catalyst activity by two different mechanisms. At low iron concentration the deactivation is mainly due to the direct poisoning of acid sites while at higher iron concentration the deactivation is mainly due to pore blocking. Moreover, iron clusters formed on FCC catalyst particles catalyze dehydrogenation reactions which lead to a higher coke selectivity. Calcium contamination is also at the origin of a large deactivation of the FCC catalyst which occurs by neutralizing acid sites and in a large extension by lowering the hydrothermal stability, at the origin of an important collapse of the zeolitic component. The combined contamination by iron and calcium does not show synergetic effects. Nevertheless, the fact that coke formation increases with iron can enhance the catalyst temperature in the industrial regenerator, leading to a further negative effect of calcium via zeolite destruction.

In the present work, we have investigated how the single and combined addition of commercial separate particle additives, such as Bottom Cracking additive (BCA) and Propylene Booster additive (ZSM-5 based-PBA), to a FCC USY catalyst can influence the product distribution and quality during FCC processing. Due to the relatively low catalytic activity of the BCA additive, the increasing single addition of BCA implies a higher ratio of thermal to catalytic cracking, leading in particular to higher dry-gases and coke selectivities and a lower gasoline pool quality. The Bottom Cracking ability of the BCA additive is feed dependent and starts to be representative for high addition levels of about 50-60 wt%, allowing the increase of the LCO pool selectivity and quality. The single and low addition level (i.e. 10 wt%) of ZSM-5 based additive allows to drastically improve the light alkenes selectivity at the expense of the gasoline selectivity, improving, due to concentration effects, the quality of the FCC gasoline pool, but generally limiting the LCO selectivity and quality while the coke selectivity is little increased. The combined use of both additives looks like an interesting upgrading strategy considering that it is possible to keep a high catalytic activity, to fully take advantage of the beneficial effects of the ZSM-5 and BCA additives, and to mitigate at the same time the increase of the coke and dry gases selectivities.

El objetivo principal de este estudio es entender mejor la influencia de las cargas que tienen un alto contenido en ácidos nafténicos (ANs) en los rendimientos del proceso de craqueo catalítico en fase fluida (FCC). El estudio implica; la preparación de cargas seleccionadas para quitar específicamente los ácidos nafténicos; el estudio comparativo de los rendimientos de craqueo catalítico entre las cargas desacidificadas y originales para ver solamente la influencia de la presencia de los ácidos nafténicos. Los resultados conseguidos son muy claros, ninguna influencia directa del contenido en ácidos nafténicos se ha observado. Al contrario, el estudio del craqueo catalítico de una carga dopada con ácidos nafténicos, permitiendo trabajar bajo condiciones extremas ha demostrado, debido al alto grado de craqueo de los ácidos nafténicos, que hay una mejora de la conversión cuando aumenta el contenido en ácidos nafténicos. Por otra parte, el balance molar en COOH, el balance molar en oxígeno y el estudio del efecto a largo plazo, han mostrados que muy pocos compuestos oxigenados potencialmente son atrapados en el catalizador y por lo tanto ninguna desactivación a largo plazo debida a los ácidos nafténicos ocurre. Además, el estudio RMN de las cargas ácidas para encontrar un parámetro estructural especial presente únicamente en las cargas teniendo valores altos de TAN y que podría explicar una caída de los rendimientos del craqueo catalítico no ha mostrado ningunas particularidades. Así, en acuerdo con estos resultados, las cargas que presentan un gran contenido de ácidos nafténicos se pueden tratar en el proceso FCC sin condiciones particulares.