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Graphical abstract Highlights • Pd-containing nanoparticles were stabilized by hypercrosslinked polystyrene. • The structure and catalytic activity of Pd nanoparticles were found to be depended on the nature of the precursor. • Pd-containing nanoparticles stabilized by HPS showed high selectivity (more 85%) in the hydrogenation of FF to FA. Abstract We report the hydrogenation of furfural (FF) to furfuryl alcohol (FA) with Pd-containing catalysts stabilized by hypercrosslinked polystyrene (HPS). FF is one of the major ingredients of biooil produced by biomass pyrolysis, while FA is a source of value-added chemicals, thus, creating an effective path from biomass to important compounds. Different palladium precursors (PdCl 2 (CH 3 CN) 2 , Pd(CH 3 COO) 2) were used for the catalysts synthesis. The nature of the precursor influences the size of palladium nanoparticles. The TEM and SAXS data showed that when using PdCl 2 (CH 3 CN) 2 , a monomodal distribution of particles size with mean diameter 5.4 ± 1.2 nm was observed, whereas for Pd(CH 3 COO) 2 , multimodal particle size distribution with the mean particle sizes up to 13.8 ± 5.4 nm was observed. The comparison of the catalytic activities of Pd-containing catalysts indicated that the more disperse sample of palladium showed higher values of FF conversion and selectivity to FA because of small particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel bimetallic Ru-Co polymeric catalysts were synthesized. • Hydrogenation of levulinic acid was studied at variation of reaction conditions. • Impregnation of Co resulted in Ru redistribution inside the polymeric support. Levulinic acid (LA) is one of the substances, which can be obtained from cellulosic biomass via acid hydrolysis and serves as a precursor in the synthesis of gamma-valerolactone (GVL) – platform chemical for so-called valeric fuels. This work is devoted to the study of catalytic conversion of LA to GVL using mono- (Ru) and bimetallic (Ru-Co) catalysts based on ruthenium-containing nanoparticles immobilized in hyper-crosslinked polystyrene (HPS). It was shown that RuO 2 nanoparticles are an active phase of HPS-based Ru catalysts, which allow nearly 100 % yield of GVL at 120 °C and 2 MPa of hydrogen partial pressure for the reaction time 60 min. Introduction of cobalt in catalyst composition in a proper amount (Ru-to-Co weight ratio is 30) was found to result in Ru redistribution inside the polymeric support and, in turn, to the increase of reaction rate of LA hydrogenation. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is a substance, which can be obtained from cellulosic biomass and hydrogenated to gamma-valerolactone (GVL) – important platform chemical. This work describes the study of a ruthenium-containing catalysts synthesized by the impregnation of HZSM-5 having different silicate modulus (40, 80 or 400) with ruthenium precursor, which resulted in formation of oxidized Ru(III) and Ru(IV) species on the catalyst surface. Synthesized catalysts allowed more than 98% of LA conversion for 60 min of the reaction and 100% GVL selectivity while working at relatively mild conditions (100 °C, 1 MPa of H 2) in aqueous medium. It was demonstrated that the observed catalytic activity mainly depends on two factors: (i) concentration of strong Lewis acid centers on the catalyst surface and (ii) surface content of RuO 2 , since the synthesized catalysts needed no preliminarily activation procedure. [Display omitted] • Novel Ru/HZSM-5 catalysts were synthesized. • Hydrogenation of levulinic acid was studied at variation of reaction conditions. • RuO 2 was catalytically active phase. • Zeolite acidity was responsible for the reaction acceleration. [ABSTRACT FROM AUTHOR]

Kinetics of the selective hydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol (MBE) over Pd supported on hypercrosslinked polystyrene bearing amino-groups was studied at variation of the MBY-to-Pd ratio and reaction temperature. For the catalyst, containing 0.7 wt.% of Pd, optimal reaction conditions were found providing >98% of the MBE selectivity at 95% of the MBY conversion. Kinetic modeling and temperature variations as well as studies of a hydrogen consumption rate allowed us to suggest that a thermodynamic factor is most likely responsible for the high MBE selectivity. [ABSTRACT FROM AUTHOR]

Here, we report the development of novel Ru-containing catalysts based on porous metal oxide supports such as SnO 2 , Nb 2 O 5 , and Nb 2 Sn 5 O 15. We assessed structure, porosity, acidity and morphology of both supports and catalysts and established a relationship between surface interactions and catalytic performance in hydrogenation of biomass based levulinic acid (LA) to γ-valerolactone (GVL). All metal oxide supports stabilize small Ru-containing nanoparticles (NPs), whose makeup includes a prevailing fraction of Ru(OH) 3. Yet, Nb 2 O 5 stabilizes ∼1 nm Ru-containing NPs which are homogeneously distributed on the metal oxide surface, while for SnO 2 and Nb 2 Sn 5 O 15 , sub-nanometer NPs are formed, which are prone to aggregation to minimize surface energy. These differences are assigned to nucleation of NPs on support oxygen vacancies, whose amounts vary and are consistent with NP characteristics. The catalytic testing shows that the 100 % conversion and selectivity as well as high turnover frequency are achieved for Ru/Nb 2 O 5 , whose surface morphology includes well-dispersed 1 nm Ru-containing NPs. These and high stability of catalytic performance upon multiple reuse, make Ru/Nb 2 O 5 promising for practical applications. Furthermore, this work validates the usefulness of surface interactions on metal oxides in development of efficient catalytic systems. [ABSTRACT FROM AUTHOR]