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Diversity of heterogeneous catalysis as a discipline spanning many scales resulted in less attention to the meso-scale. An important issue in catalysis research, often overlooked by the academic community, is preparation of shaped bodies in a systematic way unraveling the scientific basis of such preparation. In particular presence of binders in shaped catalysts could influence reactions on bifunctional catalysts. Several challenges related to efficient spatial arrangement of active catalytic phases with a controlled distance between active sites are discussed. Graphical Abstract

Measurements of the zeta potential of solid heterogeneous supports are important for preparation of metal supported catalysts and for shaping zeolites into extrudates. In the current work, different types of heterogeneous support materials such as SiO2, Al2O3, and a range of beta zeolites of different silica- to-alumina ratio were analysed. It was observed that parameters such as temperature, pH and acidity significantly affect the zeta potential. In several instances, depending on the materials’ acidity and microstructure, maxima in zeta potential were observed. The solid materials were thoroughly characterized using XRD, SEM, EDX, TEM, nitrogen physisorption, Al-NMR and FTIR with pyridine before zeta potential measurements.

This perspective describes different schemes of power systems integration for various process technology in oil refining and petrochemistry with a focus on distillation. An overview is given of different methods of gas turbines and turboexpanders. Application of the organic Rankine cycle is considered for distillation processes, especially for unconventional schemes, which are integrated into the main process as stand-alone ones, as well when the working fluid of an energy system is a process stream per se. Despite a more complex structure and potential interference with the main process, such schemes are advantageous in terms of more efficient equipment utilization. Integration of turboexpanders in separation processes and in reactor units can improve energy generation efficiency 2–3 fold compared with traditional schemes of energy generation from fossil feedstock. From the economic viewpoint for distillation columns, total annual costs can be decreased by ca. 5–15% with the specific costs of additional generated electricity being very close to the costs of a heating utility.

Kinetics and thermodynamics of α -pinene oxide isomerization was investigated both theoretically and experimentally in different solvents in the temperature range of 50–140 °C using different zeolites, iron modified zeolites, Fe–H–MCM-41 and micro-mesoporous ZSM-5 derived catalysts. The aim was to elucidate the effect of solvent basicity and polarity on the product distribution in this reaction giving as the main value-added products campholenic aldehyde and trans -carveol, which are used as fragrances and perfumes. A generic kinetic first order model was developed composed of both parallel and consecutive routes. A thermodynamic analysis showed that product selectivity is determined by kinetic control and not by thermodynamics. Formation of campholenic aldehyde was favored in non-polar solvents, whereas basic solvents promoted formation of trans -carveol independent on temperature. Graphical Abstract

Kinetics of guaiacol hydrodeoxygenation (HDO) was studied using supported Mo x C–SBA-15 and as a comparison 5 wt% Pt/C under 30 bar hydrogen at 200 °C and 300 °C. Catalyst characterization was done by a range of physical methods including also determination of the amount of coke and the nature of adsorbed species. Pt/C gave 2-methoxycyclohexanol as the main product, whereas Mo 2 C–SBA-15 promoted direct deoxygenation exhibiting also strong adsorption of guaiacol on the catalyst surface and formation of oligomers. Thermodynamics of guaiacol HDO was elucidated and the reaction network was proposed based on which kinetic modelling was done. Graphic Abstract

This review fills an apparent gap existing in the literature by providing an overview of the readily available terpenes and existing catalytic protocols for preparation of terpene-derived amines. To address the role of solid catalysts in amination of terpenes the same reactions with homogeneous counterparts are also discussed. Such catalysts can be considered as a benchmark, which solid catalysts should match. Although catalytic systems based on transition metal complexes have been developed for synthesis of amines to a larger extent, there is an apparent need to reduce the production costs. Subsequently, homogenous systems based on cheaper metals operating by nucleophilic substitution (e.g., Ni, Co, Cu, Fe) with a possibility of easy recycling, as well as metal nanoparticles (e.g., Pd, Au) supported on amphoteric oxides should be developed. These catalysts will allow synthesis of amine derivatives of terpenes which have a broad range of applications as specialty chemicals (e.g., pesticides, surfactants, etc.) and pharmaceuticals. The review will be useful in selection and design of appropriate solid materials with tailored properties as efficient catalysts for amination of terpenes.

The notion of apparent activation energy is discussed in relation to structure sensitivity of complex heterogeneous catalytic reactions comprising several steps. The cases of nonuniform surfaces (intrinsic and induced) are considered, showing that the apparent activation energy depends on the cluster size and surface coverage. The theoretical analysis of the apparent activation energy was also extended for the two step sequence with deactivating catalyst by poisoning or when coking occurs as a result of the reactant interactions with an intermediate. Graphical Abstract

The deoxygenation experiments of different reactants, i.e., pure palmitic acid, stearic acid, and a technical grade stearic acid containing a mixture of 59% of palmitic and 40% of stearic acid were successfully performed over 4 wt% Pd/C mesoporous catalyst at 300 °C under 17 bar of 5% H₂ in argon. The main product in catalytic deoxygenation of saturated fatty acids, C16 and C18, were aliphatic chain length hydrocarbons containing one less carbon than the corresponding acid. Additionally it was found that the deoxygenation rates of different reactant were independent on carbon chain length of its fatty acids.

Hydrodeoxygenation (HDO) of bio-oils, lignin and their model compounds is summarized in this review. The main emphasis is put on elucidating the reaction network, catalyst stability and time-on-stream behavior, in order to better understand the prerequisite for industrial utilization of biomass in HDO to produce fuels and chemicals. The results have shown that more oxygenated feedstock, selection of temperature and pressure as well as presence of certain catalyst poisons or co-feed have a prominent role in the HDO of real biomass. Theoretical considerations, such as density function theory (DFT) calculations, were also considered, giving scientific background for the further development of HDO of real biomass.

The use of carbon dioxide in the synthesis of chemicals, such as dimethyl carbonate (DMC), constitutes an environmentally attractive alternative to hazardous and toxic reagents. However, the direct synthesis of DMC from methanol and CO 2 is characterized by low yields due to the reaction equilibrium and the thermodynamic limitations . Alkoxide ionic liquids possessing alkylimidazolium and benzalkonium cations were prepared, characterised and tested together with ZrO 2 –MgO catalyst for the synthesis of DMC from methanol and CO 2 . By using the novel ionic liquid as additives, ca. 12% conversion of methanol, and 90% selectivity to DMC was obtained at 120 °C and 7.5 MPa. The water abstracting potential of the ionic liquids influenced the conversion of methanol and the selectivity to DMC. The alkoxide ionic liquids were recovered and reused in DMC synthesis without loss in activity and selectivity. Graphical abstract Synthesis of DMC from CO 2 and methanol catalysed by ZrO 2 –MgO using ionic liquid alkoxides as water abstracting additives. Comparison of the fresh and regenerated ionic liquid at 120 °C.