PhD position in Poland (Marie Curie actions)

The Institute of Physical Chemistry of the Polish Academy of Sciences (IPC) in close cooperation with the Institute of Chemical Technology at Universität Leipzig (Germany) , will start in Nov. 2016 the call for PhD position.

PhD project: Mechanism of nanostructure formation and surface engineering for activated materials in catalysis.

See detail info here.

Supervisors: Juan Carlos Colmenares Q. (IPC), Roger Glaeser (Universität Leipzig).

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[PAPER] Adsorption of nickelocene and ruthenocene on mesoporous silica MCM-48 and activated carbon supports in supercritical carbon dioxide

New Research paper:

Adsorption of nickelocene and ruthenocene on mesoporous silica MCM-48 and activated carbon supports in supercritical carbon dioxide

Álvaro Sastre, Ángel Martín, Esther Alonso  /  J. Supercritical Fluids 117 (2016) 138-146

Available online until 24 September 2016

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Study of hemicelluloses composition of different tree species, extraction using subcritical water with a batch cascade reactor

woodchips_biofuel

Hemicelluloses from 10 different tree species commonly growing in the Castilla y Leon region have been extracted with a batch cascade reactor. Raw materials came from tree branches, cut during the seasonal pruning. The aim was to correlate the yield of hemicellulose achieved through the extractions, with the total composition and the structure of the species, identifying the best species to obtain a high concentration of hemicelluloses, high yield and high molecular weight. Continue reading

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Hydrothermal Conversion of Carbon Dioxide into formic acid and other organic compounds

daniel roman 2016

Conversions of CO2 of 65.3% with yields of formic acid of 40% were obtained by CO2 hydrothermal reduction in the frame of the project AQUA-CO2NV in High Pressure Process of the University of Valladolid. The process consists of introducing CO2 in water at temperatures above 250 ºC and at pressures over the saturation pressure of water, in order to keep water as a liquid. Metals such as Zn, Fe, Al or Ni acts as reduction agents, and they oxidized in the process. Continue reading

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Wine lees valorization: antioxidant activities

winesense

Wine lees are the dregs formed during the different fermentation steps in the vinification process.  These wine less constitute a novel source rich in polyphenols and other compound of high added value. Freeze-dried aging wine lees were, for the first time, exhaustively characterized in terms of antioxidant capacity with different assays: ORAC, HORAC, HOSC and FRAP. In order to develop this characterization, several solid-liquid extractions (5 min of stirring and 10 min of sonication) were performed with six different solvents. Furthermore, the terpene and sugar contents of the wine lees were analyzed. Continue reading

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Silica aerogels; alternative matrix for catalytic palladium nanoparticles

luismi

Effective routes to obtain more valuable products from biomass requires the design of efficient catalysts. Novel catalytic structures are therefore needed to overcome the present challenges. These novel structures require the integration of support active sites in a way that preserves their advantages and capabilities. Here, we introduce novel catalytic structures achieved by the integration of metallic nanoparticles evenly distributed in a mesoporous and high-surface aerogel.

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Disolution/Hydrolysis and repolymerization of lignin using ultrafast reactors in supercritical water

nerea1

Fig. 1. Visual cell to study hydrolysis reactions

Efficient biomass fractionation is actually one of the major challenges posed to the biorefinery, because the complex structure of the plant cell wall and the high crystallinity of cellulose make the feedstock recalcitrant to separation into its components. Isolation/pretreatment methods that result in consistent types of lignin of high quality and purity are highly desirable. In this work, depolymerization mechanisms of lignin in sub and supercritical water will be studied using a visual cell (Fig. 1), and the hydrolysis of lignin will be carried out in the continuous pilot plant shown in Figure 2, using sudden expansion micro-reactors.

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Efficient production of soy-bean lecithin – pluronic L64® encapsulated quercetin particles in nanometric scale using SFEE and PGSS drying processes

gyuri

Quercetin occurs in various fruits, vegetables and many other food components. According to preliminary studies, it has strong antioxidant-, antiviral-, antibacterial-, antihistaminic-, and anti-inflammatory effect. Due to these properties, quercetin is a highly promising material against a wide variety of diseases, including cancer. A major limitation for the clinical application of quercetin is its low bioavailability due to its low solubility in aqueous medium as human body, that makes it necessary to administrate in high doses (50 mg/kg). One way to increase the bioavailability of quercetin is to encapsulate and precipitate it in nanometric scale, using SFEE and/or PGSS drying technology.

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Catalytic hydrogenolysis of cellobiose into hexitols over Ru/Al-MCM48

alberto

Nowadays, the increasing energy demand, depletion of fossil fuels and global warming issues have motivated our society to look for alternative sources in order to produce energy, fuels and chemicals. In this sense, biomass is one of the most promising alternative carbon source which is renewable and potentially sustainable and thus a high research effort has been made for the conversion of cellulosic biomass towards platform chemicals. These kind of reactions are related to a high energy consumption and low selectivities to the desired products. Therefore, the design of selective and efficient catalysts for these purposes is a very important task. The combination of acidic properties and active metal sites in the same catalyst appears as a good alternative for the conversion of biomass into added valuable chemicals such as sorbitol. Sorbitol is an important feedstock for food and pharmaceutical industry and intermediate for the synthesis of isosorbide and 1,4-sorbitan. Moreover, in recent years the production of alkanes from sorbitol has been demonstrated by successive dehydration (on acidic sites) and hydrogenation reactions (on metallic sites).

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Heterogeneous catalysts for the extraction of arabinoxylans from wheat bran

nuria

The conversion of biomass within biorefineries into chemicals and energy is seen as a real possibility for the substitution of fossil resources. Raw materials of high lignocellulosic content are an interesting option. Nowadays wheat bran is gaining interest as raw material for biorefineries due to its high content in polysaccharides. In this sense, arabinoxylans (AX), which are the most abundant valuable components in wheat bran, are seen as suitable compounds for the production of sugar alcohols.

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