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The one-pot formation of amides by oxidative coupling of alcohols and amines via intermediate formation of methyl ester using supported gold and base as catalysts was studied using the Hammett methodology. Determining the relative reactivity of four different para-substituted benzyl alcohol derivatives showed that the first step of the reaction generates a partial positive charge in the benzylic position (i.e. by hydride abstraction), while the second step of the reaction builds up negative charge in the rate determining step. The aminolysis of the methyl ester intermediate was further investigated by means of DFT/B3LYP. The transition state structures and energies were determined for both a concerted and a neutral two-step reaction mechanism. As expected, the base-promoted two-step mechanism was found to be the most energetically favourable and this reaction mechanism was used to construct a theoretical Hammett plot that was in good agreement with the one obtained experimentally.

Here, we report the synthesis and characterization of hierarchical zeolite materials with MEL, BEA and FAU structures. The synthesis is based on the carbon templating method with an in situ-generated carbon template. Through the decomposition of methane and deposition of coke over nickel nanoparticles supported on silica, a carbon–silica composite is obtained and exploited as a combined carbon template/silica source for the zeolite synthesis. The mesoporous zeolite materials were all prepared by hydrothermal crystallization in alkaline media followed by removal of the carbon template by combustion, which results in zeolite single crystals with intracrystalline pore volumes of up to 0.44 cm3 g−1. The prepared zeolite structures are characterized by XRD, SEM, TEM and N2 physisorption measurements.

Formic acid has a great potential as a safe and convenient source of hydrogen for sustainable chemical synthesis and renewable energy storage. Here, we report a heterogeneous gold nanoparticles catalyst for efficient production of hydrogen from vapor phase decomposition of formic acid using zeolite incorporated gold nanoparticles. The catalyst is prepared by pressure assisted impregnation and reduction (PAIR), which results in a uniform distribution of small gold nanoparticles that are incorporated into zeolite silicalite-1 crystals. Consequently, the incorporated nanoparticles exhibit increased sintering stability. Based on these results, we believe that incorporation of metal nanoparticles in zeolites may find use as highly active and selective heterogeneous catalysts for the production of hydrogen in future renewable energy applications.

The increasing need for shifting to renewable feedstocks in the chemical industry has driven research toward using green aerobic, selective oxidation reactions to produce bulk chemicals. Here, we report the use of a ruthenium mixed oxide/hydroxide (RuO x ) on different support materials for the selective aerobic oxidation of ethanol to acetic acid. The RuO x was deposited onto different oxide supports using a new gas-phase reaction, which in all cases resulted in homogeneous nanoparticulate films. The RuO x particle size ranged from 0.3 to 1.5 nm. The catalytic activity was evaluated on TiO 2 , Mg 6 Al 2 (CO 3 )(OH) 16 · 4(H 2 O), MgAl 2 O 4 , Na 2 Ti 6 O 13 nanotubes, ZnO, γ -Al 2 O 3 , WO 3 , CeO 2 , and Ce 0.5 Zr 0.5 O 2 supports. The CeO 2 supported RuO x had the highest activity, and selectivity toward acetic acid, of all the materials when normalized with respect to Ru-loading. This high activity was independent of the surface area of the support and the loading of RuO x under the tested conditions. This was attributed to the highly uniform size of the RuO x deposits, demonstrating that the deposition is suitable for producing small nanoparticles at high loadings. To elucidate the reason for the promotional effect of CeO 2 , Ce 0.5 Zr 0.5 O 2 was investigated as a high oxygen storage capacity support, however, this did not result in higher catalytic activity. The high activity of CeO 2 supports compared to the low activity ZnO appear correlated to the presence of high valence Ru(VI) species analogous to that observed in literature.

During the last decade, heterogeneous catalysis using gold nanoparticles has gained importance as an efficient method for the oxidation of alcohols and aldehydes. The scope of these reactions has recently been extended to nitrogen-containing compounds, which is a particularly promising substrate class, as nitrogen is ubiquitous in both materials science and biology. It has been shown that gold nanoparticles can overcome many of the frequently encountered difficulties caused by the coordinating properties of nitrogen when using homogenous catalysis. This minireview is meant to serve as an entry point for new researchers in this emerging field and is divided into sections based upon which nitrogen-containing products are synthesized using gold nanoparticles in the critical reaction step.

Heterogeneous catalyst systems comprising ruthenium hydroxide supported on different carrier materials, titania, alumina, ceria, and spinel (MgAl2O4), were applied in selective aerobic oxidation ethanol to form acetic acid, an important bulk chemical and food ingredient. The catalysts were characterized by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and nitrogen physisorption and utilized in the oxidation of 2.5–50 wt % aqueous ethanol solutions at elevated temperatures and pressures. The effects of Ru metal loading, pretreatment of catalysts, oxidant pressure, reaction temperature, and substrate concentration were investigated. Quantitative yield of acetic acid was obtained with 1.2 wt % Ru(OH)x/CeO2 under optimized conditions (150 °C, 10 bar O2, 12 h of reaction time, 0.23 mol % Ru to substrate).

Solid catalyst systems comprised of ruthenium hydroxide supported on magnesium-based carrier materials (spinel, magnesium oxide and hydrotalcite) were investigated for the selective, aqueous aerobic oxidation of the biomass-derived chemical 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid (FDA), a possible plastics precursor. The novel catalyst systems were characterized by nitrogen physisorption, XRPD, TEM and EDS analysis, and applied for the oxidation with no added base at moderate to high pressures of dioxygen and elevated temperatures. The effects of support, temperature and oxidant pressure were studied and optimized to allow a quantitative yield of FDA to be obtained.

The salts hexaaquamagnesium furan-2,5-dicarboxylate, [Mg(H(2)O)(6)](C(6)H(2)O(5)), (I), and hexaaquanickel furan-2,5-dicarboxylate, [Ni(H(2)O)(6)](C(6)H(2)O(5)), (II), provide the first crystallographic characterization of the furan-2,5-dicarboxylate dianion. Both structures exhibit extensive three-dimensional hydrogen-bonding networks between the octahedral coordinated hexaaquametal(II) ions and the dicarboxylate anions. Although the two structures are not isomorphous, they contain essentially identical two-dimensional slabs. The distinction between the structures is that these slabs are related by translation in (II), whereas adjacent slabs in (I) are reflected relative to each other by the action of a glide plane. The reflection occurs so that the local contacts between slabs are not changed, and thus the hydrogen-bond networks are identical except for the orientation of the water molecules at the interface between slabs.

Heterogeneous ruthenium-based catalysts were applied in the selective, aerobic oxidation of 5-hydroxymethylfurfural, a versatile biomass-derived chemical, to form 2,5-furandicarboxylic acid. The oxidation reactions were performed in water with dioxygen as the oxidant at different pressures without added base. Catalysts were prepared by depositing catalytically active Ru(OH)x species on a number of different supports, such as titanium-, aluminum-, cerium-, zirconium-, magnesium- and lanthanum oxides, magnetite, spinel, hydrotalcite and hydroxyapatite. All the catalysts were found to be active in the oxidation reactions, and the choice of support was demonstrated to be important for the catalytic performance.

Here, we report a synthesis and catalytic study of hybrid materials comprised of 1–3 nm sinter-stable Au nanoparticles in MFI-type zeolites. An optional post-treatment in aqua regia effectively remove Au from the external surfaces. The size-selective aerobic aldehyde oxidation verifies that the active Au is accessible only through the zeolite micropores.

The development of biorefineries means that a key feedstock for many new processes will be sugars in various forms, such as glucose or fructose. From these feedstocks a range of chemicals can be synthesized using heterogeneous catalysis, immobilized enzymes, homogeneous catalysts, soluble enzymes, fermentations or combinations thereof. This presents a particularly interesting process integration challenge since the optimal conditions for each conversion step will be considerably different from each other. Furthermore, compared to oil-based refineries the feedstock represents a relatively high proportion of the final product value and therefore yield and selectivity in these steps are of crucial importance. In this paper using the conversion of glucose to 2,5-furandicarboxylic acid and associated products as an example, alternative routes will be compared with respect to achievable selectivity, and achievable yield.

Nanosized Na2Ti3O7, K2Ti6O13 and Cs2Ti6O13 materials were prepared and used as supports of ruthenium nanoparticles for catalytic ammonia decomposition. It is shown that these catalysts exhibit higher catalytic activity than ruthenium supported on TiO2 nanoparticles promoted with cesium. The difference is attributed to the use of nanostructured materials with incorporated alkali metals in the crystal lattice, which apparently gives a higher effect of the promoter. All samples were characterized by X-ray powder diffraction, transmission electron microscopy and N2 physisorption measurements. Furthermore, the effect of ruthenium loading on the catalytic decomposition of ammonia was investigated.

The structure sensitivity of different transition metals in the hydrogenolysis, dehydrogenation, and coking reactions during ethane conversion has been investigated. The investigated metals, Ni, Ru, Rh, and Pd, are co-impregnated with Ag onto an inactive MgAl2O4 spinel support and tested in the conversion of ethane. A tendency is clear for all catalysts: In the first period of time 100% ethane is converted and roughly half of the carbon is converted into coke and deposited on the catalyst. The other half of the carbon is converted into methane. The active sites in the hydrogenolysis are blocked by coke during the initial period where after dehydrogenation of ethane is observed. It has previously been predicted in surface science studies that Ag covers the steps of certain transition metals. Here it is documented that the hydrogenolysis and coking reactions are significantly suppressed by co-impregnation of Ag and Ni. The effect of Ag is limited for Ru since the active sites are self-poisoned by carbon; nor for Rh/spinel is the effect observed, which is possibly due to island formation of Ag on the terraces of the Rh metal. A prolongation of the initial period with hydrogenolysis is observed for Ag-Pd/spinel due to an alloy formation of Ag and Pd at these conditions. From our results it can therefore be concluded that hydrogenolysis mainly takes place on the steps and kinks of the transition metal particles, dehydrogenation reactions mainly takes place on the terraces, and coking is significantly reduced by covering the steps sites by Ag. This important information can be used in designing new catalysts with improved selectivity and stability.

Gold nanoparticles are deposited on potassium titanate nanowires and used as heterogeneous catalysts in the aerobic oxidation of benzyl alcohol in methanol to methyl benzoate at ambient conditions. The presence of a catalytic amount of base promotes the reaction and the formation of free benzoic acid during the reaction poisons the catalyst. The activity however, of the catalyst can be restored again by addition of base.

Boron nitride coatings on high-surface area MgAl2O4 and Al2O3 have been synthesized and characterized by transmission electron microscopy and by X-ray powder diffraction. The metal oxide templates were coated with boron nitride using a simple nitridation in a flow of ammonia starting from ammonium borate adsorbed on MgAl2O4 or γ-Al2O3. This procedure resulted in the formation of a turbostraticboron nitride film with a thickness of a few individual BN layers.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The observation of chain-like structures of self-assembled C 60 molecules on HOPG surfaces at room temperature in aerial atmosphere by means of scanning tunneling microscopy is reported. The ca. 2.5 nm center-to-center distance between two fullerene molecules is much larger than in the close-packed layered or film structures of C 60 usually found on HOPG surfaces.

We report the synthesis and characterization of a series of new mesoporous zeolite and zeotype materials made available by combining new and improved procedures for directly introducing carbon into reaction mixtures with the fluoride route for conventional zeolite synthesis. The mesoporous materials were all prepared by hydrothermal crystallization of gels adsorbed on carbon matrices which were subsequently removed by combustion. The procedures presented here resulted in mesoporous zeolite and zeotypes materials with MFI, MEL, BEA, AFI and CHA framework structures. All samples were characterized by XRPD, SEM, TEM and N2 physisorption measurements. For the zeolite materials it was found that mesoporous MFI and MEL structured single crystals could indeed be crystallized from fluoride media using an improved carbon-templating approach. More importantly, it was found that mesoporous BEA-type single crystals could be crystallized from fluoride media by a newly developed procedure presented here. Thus, we here present the only known route to mesoporous BEA-type single crystals, since crystallization of this framework structure from basic media is known to give only nanosized crystals as opposed to mesoporous single crystals. For the zeotype materials it was found that highly crystalline mesoporous materials of AFI and CHA structure types could be synthesized using a newly developed procedure.

Caught in the act: Until now, the spatial property of the hyperfine interaction between the S=2 electronic spin and the I=5/2 nuclear spin in any chemically relevant MnIII compound has escaped observation. By taking multifrequency electron paramagnetic resonance measurements (see graph) on the [Mn(OH2)6]3+ ion doped into Cs[Ga(OH2)6](SO4)6 H2O, ground-state spin Hamiltonian parameters have been determined at an unprecedented level of precision.

Mesoporous titanium silicalite-1 (TS-1) prepared by carbon-templating is significantly more active than conventional TS-1 for the oxidation of pyridine derivatives using aqueous hydrogen peroxide as oxidant. The catalytic activity is increased by the system of mesopores that helps to overcome the configurational diffusion limitations within the microporous catalyst. The use of a carbon-template for generation of secondary porosity is more effective than desilication. The desilicated catalyst is slightly more active than conventional TS-1, probably due to a decrease of the mean diffusion path length. In contrast, carbon-templated mesopores provides an efficient transport throughout the zeolite, thus preventing deactivation due to product confinement. All catalysts were characterised by X-ray powder diffraction, scanning electron microscopy, UV–Vis spectroscopy and nitrogen physisorption. The results indicate that desilication may cause a surface densification of less catalytically active extra-framework Ti species. Carbon-templating is thus a more gentle and effective method for generating secondary porosity. Utilization of carbon-templated mesoporous TS-1 for oxidation of pyridine derivatives represents a new and environmentally friendly method to synthesise N-oxides., We gratefully acknowledge the support of the Danish Council for Independent Research, Grant No. 10-093717 and Grant No. 12-127580. We would also like to thank for support from the Spanish Ministry of Science and Innovation (project CTQ2011-25517), and Unidad de Apoyo from Catalysis Institute (ICP-CSIC).

With the ongoing developments in biomass conversion, the oxidation of bioethanol to acetaldehyde may become a favorable and green alternative to the preparation from ethylene. Here, a simple and effective method to encapsulate gold nanoparticles in zeolite silicalite-1 is reported and their high activity and selectivity for the catalytic gas-phase oxidation of ethanol are demonstrated. The zeolites are modified by a recrystallization process, which creates intraparticle voids and mesopores that facilitate the formation of small and disperse nanoparticles upon simple impregnation. The individual zeolite crystals comprise a broad range of mesopores and contain up to several hundred gold nanoparticles with a diameter of 2-3 nm that are distributed inside the zeolites rather than on the outer surface. The encapsulated nanoparticles have good stability and result in 50 % conversion of ethanol with 98 % selectivity toward acetaldehyde at 200 °C, which (under the given reaction conditions) corresponds to 606 mol acetaldehyde/mol Au hour(-1) .

We describe a solid polyphenylene support that serves as an excellent platform for metal-catalyzed reactions that are normally carried out under homogeneous conditions. The catalyst is synthesized by palladium-catalyzed Suzuki coupling which directly results in formation of palladium nanoparticles confined to a porous polyphenylene network. The composite solid is in turn highly active for further Suzuki coupling reactions, including non-activated substrates that are challenging even for molecular catalysts. A major goal in catalysis is to combine the advantages of molecular catalysts and heterogeneous processes, ideally maintaining—or even improving—the reactivity and selectiv- ity of the molecular catalysts, while facilitating product recovery and catalyst recycling. (1-3) However, in fine-chem- icals synthesis molecular catalysts are predominantly used, partly because typical solids do not provide the nonpolar environments often required for organic reactions. This is often easier realized with metal complexes and suitable ligands and solvents, which provide the required geometry and stabilize the transition state of the reaction. (4-6) Polymers as less conventional supports could provide a "solvent"-like reaction environment, onto which ligands and metal com- plexes can be grafted to provide the catalytic functionality. (7, 8) Polymeric solids based on polystyrene, (9, 10) polydivinylben- zene (PDVB), (11) polyacrylate derivatives, (12) covalent organic frameworks (COF), (13) and hybrid metal-organic frame- works (14-16) have recently been explored as carriers for catalytic metal nanoparticles. Commercially, polymeric catalyst supports are limited to ion-exchange resins, for example, the Amberlyst series based on polystyrene-co-divinylbenzene. Also carbon materials are widely applied when an apolar carrier material is required to host metal catalytic species. (17) In our search for intermediate materials between carbons and the polymers listed above, we decided to study the performance of polyphenylene (PPhen) in catalysis. In this polymer, all the carbon atoms are sp 2 hybridized. The thermal and chemical stability of PPhen is higher than those of most other polymers, while it still provides a "solvent-like" reaction environment, suggesting its

Gas separation by ionic liquids (ILs) is a promising new research field with several potential applications of industrial interest. Thus cleaning of industrial off gases seems to be attractive by use of ILs and Supported Ionic Liquid Phase (SILP) materials. The potential of selected ILs for absorption of NOX, CO2 and SO2 are demonstrated and the possible mechanism of absorption described on the molecular level. Special focus regards the interaction of the ILs with water vapor, which is an important feature in envisaged application of flue gas cleaning in power plants, waste incineration plants, cement and glass factories as well as on board ships.

A new, green protocol for producing simple esters by selectively oxidizing an aldehyde dissolved in a primary alcohol has been established, utilising air as the oxidant and supported gold nanoparticles as catalyst. The oxidative esterifications proceed with excellent selectivities at ambient conditions; the reactions can be performed in an open flask and at room temperature. Benzaldehyde is even oxidised at a reasonable rate below −70 °C. Acrolein is oxidised to methyl acrylate in high yield using the same protocol.

Silver nanoparticles supported on alumina were prepared and tested in the catalytic reduction of various imines to primary and secondary amines and were shown to be exceptionally active and chemoselective. Furthermore, the catalytic activity of the prepared nanocatalyst was also tested in the synthesis of secondary amines from primary amines in a tandem reaction protocol (oxidation–imination–reduction) using air and molecular hydrogen as oxidizing and reducing agents, respectively. The reported synthesis is performed under mild reaction conditions, which complies with the demands of modern organic synthesis. Due to the mild reaction conditions and high conversion as well as high selectivity, we consider that the utilization of silver nanoparticles supported on alumina represents an attractive and environmentally friendly alternative to the current synthesis of N-alkyl amines.

The catalytic performance of zeolite‐supported vanadia catalysts was examined for the aerobic oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF) in organic solvents such as N,N‐dimethylformamide (DMF), methyl isobutyl ketone, toluene, trifluorotoluene and DMSO. Catalysts based on the four different zeolite supports H‐beta, H‐Y, H‐mordenite, and H‐ZSM‐5 with 1–10 wt % vanadia loading were prepared and characterized by nitrogen physisorption, X‐ray powder diffraction, scanning electron microscopy, ammonia temperature‐programmed desorption, Raman spectroscopy and UV/Vis spectrophotometry. The H‐beta zeolite catalysts were found to contain highly dispersed vanadium oxide species at all loadings, and provided the highest reaction selectivity towards DFF and the lowest metal leaching of the examined systems. In particular, 1 wt % V2O5/H‐beta was found to be a stable, recyclable, and non‐leaching catalyst for the production of DFF under mild conditions in DMF as solvent, although with low DFF yield. To increase the yield, oxidation of HMF at elevated pressures was also investigated with this catalyst. Under optimized conditions, a reaction selectivity towards DFF of >99 % at 84 % HMF conversion was obtained, albeit with some contribution from lixiviated species to the total catalyst activity., The authors thank Bodil F. Holten (CSC, DTU) and Anders B. Laursen (CINF, DTU) for assistance during catalyst characterization. The Danish Agency for Science, Technology and Innovation provided a grant (#09‐065038/FTP) for the UV‐laser Raman instrumentation. I.S. is grateful to the Spanish National Research Council (CSIC) for a JAE‐Predoc grant and for financial support to the research stay at CSC, Technical University of Denmark.

During the last decade, heterogeneous catalysis using gold nanoparticles has gained importance as an efficient method for the oxidation of alcohols and aldehydes. The scope of these reactions has recently been extended to nitrogen-containing compounds, which is a particularly promising substrate class, as nitrogen is ubiquitous in both materials science and biology. It has been shown that gold nanoparticles can overcome many of the frequently encountered difficulties caused by the coordinating properties of nitrogen when using homogenous catalysis. This minireview is meant to serve as an entry point for new researchers in this emerging field and is divided into sections based upon which nitrogen-containing products are synthesized using gold nanoparticles in the critical reaction step.

Synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines via intermediate formation of methyl esters is highly efficient and selective when using a catalytic system comprised of supported gold nanoparticles and added base in methanol.

Synthesis of amides by aerobic oxidative coupling of alcohols or aldehydes with amines via intermediate formation of methyl esters is highly efficient and selective when using a catalytic system comprised of supported gold nanoparticles and added base in methanol.

Over the past decades it has become clear that supported gold nanoparticles are surprisingly active and selective catalysts for several green oxidation reactions of oxygen-containing hydrocarbons using molecular oxygen as the stoichiometric oxidant. We here report that bifunctional gold–titania catalysts can be employed to facilitate the oxidation of amines into amides with high selectivity. Furthermore, we report that pure titania is in fact itself a catalyst for the oxidation of amines with molecular oxygen under very mild conditions. We demonstrate that these new methodologies open up for two new and environmentally benign routes to caprolactam and cyclohexanone oxime, both of which are precursors for nylon-6.

A new, green protocol for producing simple esters by selectively oxidizing an aldehyde dissolved in a primary alcohol has been established, utilising air as the oxidant and supported gold nanoparticles as catalyst. The oxidative esterifications proceed with excellent selectivities at ambient conditions; the reactions can be performed in an open flask and at room temperature. Benzaldehyde is even oxidised at a reasonable rate below −70 °C. Acrolein is oxidised to methyl acrylate in high yield using the same protocol.

We present the angular variation of the resonance magnetic fields as well as the angular variation of the linewidths obtained from single-crystal electron paramagnetic resonance spectra of Δ ( + ) [Cr(( − )chxn) 3 λ λ λ ] 3+ (chxn = trans -1,2-cyclohexanediamine) doped into the nitrate salt of the isostructural Rh(III) ion Δ ( + ) [Rh(( − )chxn) 3 λ λ λ ](NO3)3⋅3 H 2 O. An analysis of the angular variation of the resonance magnetic fields indicates axial symmetry for the cation. An analysis of the angular variation of the linewidths, on the other hand, reveals that not all the paramagnetic sites have perfect axial symmetry.

Gas separation by ionic liquids is a promising new research field with several applications of industrial interest. Thus cleaning of industrial off gases seems to be attractive by use of ionic liquids and Supported Ionic Liquid Phase (SILP) materials. The potential of selected ionic liquids for absorption of NOx, COx and SOx will be demonstrated and the possible mechanism of absortion will be described on the molecular level. Our vision of application of these ionic liquids to flue gas cleaning in power plants, waste incineration plants, cement and glass factories as well as unborad ships will be adressed.

The structure of the title complex, [CrCl3(C9H21N3)], contains a distorted octa­hedral chromium(III) centre. The facial tridentate N-coordinating 1,4,7-trimethyl-1,4,7-triaza­cyclo­nonane ligand and three chloride ions make up the first coordination sphere.

This perspective covers the use of molybdenum disulfide and related compounds, generally termed MoSx, as electro- or photoelectrocatalysts for the hydrogen evolution reaction (HER). State of the art solutions as well as the most illustrative results from the extensive electro- and photoelectrocatalytic literature are given. The research strategies currently employed in the field are outlined and future challenges pointed out. We suggest that the key to optimising the HER activity of MoS2 is divided into (1) increasing the catalytic activity of the active site, (2) increasing the number of active sites of the catalyst, and (3) improving the electrical contact to these sites. These postulations are substantiated by examples from the existing literature and some new results. To demonstrate the electrocatalytic properties of a highly conductive MoS2 hybrid material, we present the HER activity data for multi-wall MoS2 nanotubes on multi-wall carbon nanotubes (MWMoS2@MWCNTs). This exemplifies the typical data collected for the electrochemical HER. In addition, it demonstrates that the origin of the activity is closely related to the amount of edges in the layered MoS2. The photoelectrocatalytic HER is also discussed, based on examples from literature, with an emphasis on the use of MoSx as either (1) the co-catalyst providing the HER activity for a semiconductor, e.g. Mo3S+4on Si or (2) MoS2 as the semiconductor with an intrinsic HER activity. Finally, suggestions for future catalyst designs are given.

Emission of acidic gases such as NOX and SOx and COx, which are produced by combustion of fossil fuels during, e.g. energy production in power plants, is a major concern in relation to atmospheric pollution and climate changes by the so-called green-house effect. Accordingly, these gases have to be effectively removed from flue gases. Presently this is mainly achieved by relatively energy intensive and resource demanding technologies via selective catalytic reduction (SCR) of NOX with ammonia, by gypsum formation after SO2 wetscrubbing while organic amines are being used as absorbents in CO2 scrubbers leading to concern about, e.g. intensive energy requirements for desorption, corrosion of steel pipes and pumps, CO2 absorption capacity and thermal decomposition of the amine. In this work, we demonstrate how ionic liquids can be tuned by design to perform as selective, high-capacity absorbents of environmentally problematic flue gases like, e.g. SO2 , NO and CO2 . Reversible absorption performance has been tested for several different ILs at different temperatures and flue gas compositions. The structures of ILs are well-ordered even in the liquid state with regular cavities which can host selected solute species depending on the IL ion composition. ILs can be tuned to absorb selected gas molecules making them promising materials for selective, reversible absorption of gaseous pollutants in, e.g. power plant flue gases and other exhaust or industrial offgases.[1,2] In the present work ionic liquids composed of imidazolium or guanidinium based cations like EMIM, BMIM, OMIM and TMGH and anions like acetate, sulphate, triflate and halogenides have been selected for absorption of SO2 and for the first time as far as we know also for NO . Task-specific ionic liquids have been developed[3] which are able to make a chemical bond between CO2 and amine-functionalized ILs at ambient conditions. It appears, however, that this type of bonding is too strong to make reversible absorption/desorption economic in technical scale. Therefore, we have set out to synthesize new ionic liquids containing alternative nitrogen-based functionalities which absorb CO2 readily but less strongly than corresponding amine-based ILs. It is anticipated that the new ionic liquids could improve both chemical and physical absorption of CO2 by proper choice of substituents while maintaining an acceptable enthalpy of absorption and desorption. Reversible absorption performance has been tested for several different ILs at different temperatures and flue gas compositions. Furthermore, different porous, high surface area carriers have been applied as supports for the ionic liquids to obtain Supported Ionic LiquidPhase (SILP) absorber materials.[4] The use of solid SILP absorbers with selected ILs were found to significantly improve the absorption capacity and sorption dynamics at low flue gas concentration, thus making the applicability of ILs viable in technical, continuous flow processes for flue gas cleaning. The results show that CO2 , NO and SO2 can be reversible and selective absorbed using different ILs and that Supported Ionic Liquid-Phase (SILP) absorbers are promising materials for industrial flue gas cleaning. Absorption / desorption dynamics can be tuned by temperatures, pressures and gas concentrations.

The formation of imines by aerobic oxidative coupling of mixtures of alcohols and amines was studied using gold nanoparticles supported on titanium dioxide, TiO2, as a heterogeneous catalyst. The reactions were performed at ambient conditions (room temperature and atmospheric pressure) and occurred with excellent selectivity (above 98%) at moderate conversion under optimized conditions. The effect of catalytic amounts of different bases was studied, along with reaction temperature and time. Utilisation of a selective catalyst system that uses dioxygen as an oxidant and only produces water as by-product represents a new green reaction protocol for imine formation.

Over the past decades it has become clear that supported gold nanoparticles are surprisingly active and selective catalysts for several green oxidation reactions of oxygen-containing hydrocarbons using molecular oxygen as the stoichiometric oxidant. We here report that bifunctional gold–titania catalysts can be employed to facilitate the oxidation of amines into amides with high selectivity. Furthermore, we report that pure titania is in fact itself a catalyst for the oxidation of amines with molecular oxygen under very mild conditions. We demonstrate that these new methodologies open up for two new and environmentally benign routes to caprolactam and cyclohexanone oxime, both of which are precursors for nylon-6.

The research interests in biomass conversion to fuels and chemicals has increased significantly in the last decade in view of current problems such as global warming, high oil prices, food crisis and other geopolitical scenarios. Many different reactions and processes to convert biomass into high-value products and fuels have been proposed in the literature, giving special attention to the conversion of lignocellulosic biomass, which does not compete with food resources and is widely available as a low cost feedstock 1. Lignocellulose biomass is a complex material composed of three main fractions: cellulose (40-50%), hemicellulose (25-35%) and lignin (20-30%) 2. Lignin is mainly composed of three different monolignol monomers: p-coumaryl, coniferyl and sinapyl alcohol 2. These monomers are connected with various linkages with the most common one being the ß-O-4 linkage 3. The lignin structure is complex so different model compounds are often used to study lignin valorization. These model compounds contain the linkages present in lignin, simplifying catalytic analysis and present analytical challenges related to the study of the complicated lignin polymer and the plethora of products that could be obtained 2. Heiko Lange et al., has reported that the catalytic oxidation products of lignin and lignin model compounds range from aromatic aldehyde and carboxylic acid and they must be originate form oxidation of side chain. The products we obtained in these reactions are based on the severity of the reaction conditions 4. Here, we therefore present an overview of the recent research about conversion of some lignin model compounds using heterogeneous catalysis in oxidation reactions.