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[Display omitted] • The APR of wastewater streams close to industrial complexity has been reviewed. • Food, biodiesel and lignocellulosic processing lead to by-products valorized via APR. • The differences between real and theoretical results are highlighted and examined. • The integration with other technologies is discussed to promote benefic synergies. Wastewater is of general concern for environmental sustainability. At the industrial level, carbon-laden aqueous streams must be treated and should be valorized to reduce environmental and economic concerns. Lignocellulosic biomass processing (such as hydrolysis, pyrolysis, and hydrothermal liquefaction) results in secondary aqueous streams in which a high fraction of the initial carbon content of the biomass is virtually lost; food industry (like breweries and cheese factories) produces streams with a variety of organic load and salinity, which may complicate conventional valorization treatments; biodiesel production leads to glycerol excess in the market, which needs to be valorized. Among other alternatives, aqueous phase reforming (APR) has been proposed as a process driven at relatively mild conditions, able to convert oxygenated molecules into hydrogen. Despite its potential, APR has commonly been investigated with model compounds, and a systematic study on the possible fields of application of this technology is lacking. In the present review, the study of the available literature was focused on the valorization of complex feedstocks, such as real waste streams or synthetic mixtures, showing the outcome derived from laboratory-scale experiments. The results were critically discussed, pointing out the present limitations for the full development of this process and its application to the industrial scale. Despite the challenges of APR, its potential is noteworthy for the development of a circular low-waste economy. [ABSTRACT FROM AUTHOR]

The aqueous phase reforming (APR) is a catalytic reaction able to produce hydrogen from oxygenated compounds. The catalytic system plays a pivotal role to permit high conversion of the substrate, high selectivity towards hydrogen, and stability in the view of an industrial application. These figures of merit depend on several strategies taken by the researchers to properly design the catalyst, like the preparation method, the choice of the active metal together with possible promoters, the type of the support and so on. The available literature reports several studies where these parameters are evaluated and discussed. In this review, they were critically examined with the aim of finding correlations between the properties of the catalyst and the activity, selectivity and stability for the APR of carbon-laden water fractions. Both theoretical and experimental works have been included in the literature survey. When available, studies with the use of in-situ techniques allowed to increase the understanding of the catalytic phenomena involved in the reaction. Great attention was also reported to recently published works, so that the review could present the most up-to-date developments in the field. The most important outcomes regarding each parameter have been highlighted; moreover, the synergy among each of them has been pointed out, together with the trade-off that the researcher has to deal with in the pursuit of the optimum catalyst. [Display omitted] • The research on catalyst design for aqueous phase reforming has been reviewed. • The effect of preparation method, metal choice and support was evaluated. • Use of first-principle approaches and in-situ techniques was reported. • Challenges and perspectives for optimal catalyst system were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The role of acidity and passivation of ZSM_5 was studied in DME-to-Olefins process. • Light olefins selectivity reached 60 %, with methanol as side product at low T. • Propylene was the most abundant produced hydrocarbon. • Alkene cycle of hydrocarbon pool mechanism seems to be the main reaction pathway. • Passivation of ZSM-5 (Si/Al = 25) improved the catalyst stability. In the present study, four different samples having different acidity were synthesized. Two MFI-type zeolites having silicon-to-aluminum ratio equal to 25 and 50 were prepared. Besides, two additional samples were obtained by external passivation of each parent zeolite with a layer of Silicalite-1, leading to a core–shell structure. Each sample was characterized to assess textural properties, structure, composition, and acidity, and then tested for dimethyl ether (DME) conversion at different reaction temperatures between 300 and 375 °C. The analysis of produced mixture revealed the simultaneous presence of hydrocarbons and methanol. DME conversion grew by increasing the temperature. Propylene was the most abundant hydrocarbon detected during all the time-on-stream analyses. Especially at 375 °C, the investigated samples having greater acidity showed faster deactivation due to coking. Samples with lower acidity were thus more stable but, on the other hand, they presented higher methanol selectivity and lower hydrocarbons yield. [ABSTRACT FROM AUTHOR]

[Display omitted] • An innovative double-stage HTL was tested for oil production from PVC. • 99% of Cl was removed and 94% of C was retained in the solid after subcritical HTL. • Addition of KOH affected dechlorination mechanisms mostly at low temperatures. • Supercritical HTL enabled 32% conversion of solid carbon into gas-oily hydrocarbons. • Double-stage HTL produces HCl solution, 29 wt.% of Cl-free char and hydrocarbons. Poly(vinyl chloride) (PVC) is globally the third most produced plastic, but recycling PVC waste through mechanical means is difficult. Due to the high presence of chlorine in PVC, it is unsuitable for both pyrolysis and combustion. Consequently, there is a need to explore innovative methods for harnessing its energy potential. Hydrothermal liquefaction (HTL) is a topic of growing interest in the literature for chemical recycling of waste plastic or conversion into liquid energy carriers. In this work an innovative sequential hydrothermal processing strategy was tested for oil production from PVC. PVC at high loadings (20 wt.%) was first processed under subcritical conditions to produce a chlorine-free solid, which was then liquefied in supercritical conditions. Different temperatures were tested for the dechlorination stage, and at 300 °C 99% of chlorine was removed, while 94% of carbon remained in the solid residue. The mechanism behind the solid's formation was investigated by assessing activation energies, both with the addition of KOH as a neutralizing agent (120 kJ/mol) and without it (186 kJ/mol). Different temperatures were screened for an HTL supercritical stage (420–480 °C), but the maximum conversion of the dechlorinated solid was 47%, and the maximum mass yield of oil was 10%. Overall, the subcritical phase demonstrated its potential as a technology for producing chlorine-free solid material with a high energy density. The subsequent supercritical step partially valorized the dechlorinated solid by producing an aromatic-rich oil phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Different heating rates were tested in HTL of model compounds and real food waste. • Heating rate strongly affected HTL performances at lower residence times. • Heating rate influence at longer residence times was limited. • HTL performance was well described by the kinetic severity factor. Hydrothermal liquefaction (HTL) emerges as an efficient technology for converting food waste into biocrude. Among HTL parameters, the impact of heating rate is understudied. This study systematically explores its variation (5–115 K/min) on HTL performance using actual food waste and model compounds representing its constituents. Results revealed that an increase in heating rates significantly impacts HTL performances (+63 % biocrude and −34 % solid with food waste) with short residence times, as slower heating rates imply a longer overall time and a higher kinetic advancement of the reaction. Conversely, with longer residence times, the influence of heating rates becomes negligible, as kinetics during heating times are overshadowed by those at operating temperatures. A subtle effect of heating variation at extended residence time was observed only with carbohydrates. This research emphasizes the utility of a kinetic severity factor (KSF) as a valuable tool for simultaneously considering heating rates, operating times, and temperatures. [ABSTRACT FROM AUTHOR]

A set of Dual Function Materials (DFMs) was prepared to seize the CO 2 from a rich feed gas and to in-situ convert it to methane (synthetic natural gas). Specifically, ruthenium-ceria composite materials were synthesized through successive impregnation depositions on two high surface area supports, namely Al 2 O 3 and ZSM-5. Cerium oxide has both the roles of CO 2 adsorbent and promoter support for ruthenium, which represents the active component for methanation. Three different quantities of ceria (10, 20, and 30 wt%) were dispersed onto the solid supports, and the adsorption capacities of the ceria-based materials were studied at different temperatures (150, 200, and 250 °C) at atmospheric pressure. The samples exhibiting the best results in terms of CO 2 adsorption (30 wt% CeO 2 /Al 2 O 3 and 30 wt% CeO 2 /ZSM-5) were subsequently impregnated to obtain ruthenium-loaded catalysts (2 wt% Ru). These functionalized materials were characterized by XRD, N 2 physisorption at − 196 °C, TPDRO, ICP-MS, XPS, FESEM, HRTEM, and FT-IR. Then, cyclic experiments of CO 2 adsorption and methanation were performed, simulating a real use of the catalysts at 250 °C and atmospheric pressure. The deposition of ruthenium-ceria on a high surface area support was found to be crucial for maintaining the methanation activity of this catalytic system under cyclic CO 2 adsorption-hydrogenation conditions. The Al 2 O 3 -supported ruthenium-ceria catalyst adsorbed a lower amount of CO 2 (ca. 200 μmol g−1 per each cycle) with respect to the zeolite-supported sample (ca. 300 μmol g−1); nevertheless, the former material presented the best methanation performances, thanks to an intermediate ruthenium-ceria interaction, yielding a maximum of 51% of CO 2 converted and producing up to 111 μmol g−1 of CH 4. [Display omitted] • As-prepared Ce-based samples show good CO 2 adsorption capacity at high temperature. • Synergic action of zeolite support allows a further rise in the adsorption capacity. • Cyclic methanation tests were performed, simulating continuous work of the material. • The catalysts are selective towards CH 4 production and active at ambient pressure. • A great stability is exhibited by the catalysts during cyclic experiments. [ABSTRACT FROM AUTHOR]

This article presents an investigation on the recovery of CO 2 from the combustion gases of the cement industry through a carbonation route in order to obtain Calcium Carbonate Nanoparticles (CCnP), which could find application as either polymer or cement fillers. Two different experimental setups, a Continuously Stirred Bubbling Reactor (CSBR) and a Packed Bed Reactor (PBR), were studied in order to improve the final product and enhance the process yield. The influence of the experimental parameters on the particle size and morphology was tested for both reactors. The process was intensified by employing the PBR, where cubic calcite particles smaller than 300 nm were synthesized and higher CO 2 conversions were obtained with respect to the CSBR performance. Unlabelled Image • CaCO 3 particles were synthesized through a carbonation route in different setups • By using a packed bed reactor (PBR), the process yields on CO 2 were increased • Size and morphology of CaCO 3 can be tailored by varying the operating conditions • Cubic calcite nanoparticles were obtained with optimized conditions in the PBR [ABSTRACT FROM AUTHOR]

A group of catalysts was developed with the purpose of enhancing the soot oxidation in the selective catalytic reduction on filter system, without negatively effecting the NOx conversion associated to NH3 oxidation. The impregnation with alkali metal of a series of supports, characterized by a lack of strong superficial acid sites, improved soot oxidation simultaneously preventing ammonia adsorption, thus its catalytic oxidation. Strong synergy was observed between a ZrO2–CeO2 support and potassium, decreasing the T50 of the soot conversion of 170 °C in loose contact. This catalyst was added to a Fe-ZSM5 selective catalytic reduction (SCR) catalyst without negative effect for the SCR activity. The complex interaction between the potassium-based soot oxidation catalyst and the SCR one was investigated. The soot–soot oxidation catalyst-SCR catalyst contact mode was found to be a key factor and the increased contact of the soot–soot oxidation catalyst is preferable. Such dual component catalyst system was demonstrated to be promising for simultaneous removal of NOx and soot on a single filter. [ABSTRACT FROM AUTHOR]

• Competitive adsorption in the valorization of wastewater via APR was investigated. • Combination of catalytic experiments and DFT modelling applied. • Glycolic acid significantly impedes conversion of both acetic and propionic in mixtures. • At high coverage, carboxylic acids preferentially adsorbed into dimer structures. • Adsorption strength trends found via DFT modelling reflected the experimental results. Biorefinery-derived wastewater is considered a valuable source of energy and chemicals thanks to its organic loading. However, it is constituted by different compounds which influence the performance of a catalytic valorization process. In this work, we investigated the treatment of a synthetic hydrothermal liquefaction-derived wastewater (HTL-WW) via aqueous phase reforming (APR) to obtain hydrogen. As a case study, we examined the underlying driving forces for performance differences in the APR of mono- and bi-component solutions of carboxylic acids as a model corn stover HTL-WW over Pt catalysts via a combined experimental and theoretical approach. In mono-component solutions, the conversion ranked as glycolic acid > propionic acid ≈ acetic acid, and the same was found for the hydrogen production tendency. Binary solutions of glycolic and acetic acid, with different concentration among the constituents, showed a strong inhibition of the acetic acid reactivity due to the prevalent adsorption of glycolic acid on Pt surface. The results from the APR of acetic and propionic acid solutions were less affected by such phenomena. DFT results showed that there are strong, attractive lateral interactions between carboxylic acids due to intermolecular hydrogen bonding that cause all carboxylic acids to preferentially adsorb in dimer structures. The lateral interaction strength was determined for both pure and binary mixtures of carboxylic acid dimers, with results showing that pure mixtures of carboxylic acids have stronger attractions and that glycolic acid dimers see the strongest attractions due to the added terminal hydroxyl functional group. The findings presented herein offer significant insights into the utilization of APR for industrial-like multi-component solutions, as well as for any catalytic process involving small organic compounds in an aqueous phase. [ABSTRACT FROM AUTHOR]

A set of Cu-Mn oxides was prepared through the simple and effective solution combustion synthesis method by varying the relative amount of copper and manganese. The physico-chemical properties of the samples were investigated through complementary techniques such as N 2 physisorption at − 196 °C, XRD, HR-TEM, Raman spectroscopy, temperature programmed analyses (H 2 -TPR, O 2 -TPD, and NH 3 -TPD), and XPS. The prepared catalysts were tested for the total oxidation of volatile organic compounds (ethylene, propylene, and toluene). The best performances, in terms of total VOC oxidation, were achieved with a copper content ranging from 15 at% to 45 at%. The catalytic test outcomes demonstrate the beneficial effect of acidic sites, oxygen mobility, and redox ability. In particular, ethylene oxidation is mainly favored by oxygen vacancies and redox properties, while propylene and toluene oxidation is mostly enhanced by acidic sites. All the catalysts prepared can totally oxidize the examined pollutants examined below 310 °C. Moreover, the binary oxides exhibit good catalytic stability over a time-on-stream of 7 h and low water vapor inhibition (5 vol% H 2 O in the gas stream). [Display omitted] • Cu-Mn oxides are effective catalysts for ethylene, propylene and toluene oxidations. • Solution Combustion Synthesis is the technique used to prepare Cu-Mn oxides. • The Cu-Mn oxide catalysts exhibit good stability. • Different oxidation mechanisms take place with ethylene, propylene and toluene. • Low catalytic deactivation occurs in the presence of water vapor 5 vol%. [ABSTRACT FROM AUTHOR]

In recent decades, climate change has become a major issue that needs to be addressed. Many efforts have been made on the reduction of CO 2 emissions and its conversion in energy carriers and high value-added products such as methane, methanol, dimethyl-ether, and hydrocarbons. The present study focuses on the development of catalysts for hydrogenating CO 2 to methanol, which is a useful chemical and an alternative liquid fuel. According to the literature, In 2 O 3 -based catalysts are particularly selective in the hydrogenation of CO 2 to methanol, reducing the production of CO even at high space velocities compared to the more common ternary catalysts such as Cu/ZnO/Al 2 O 3 or Cu/ZnO/ZrO 2. Therefore, the effects of CeO 2 and ZrO 2 on In 2 O 3 -based catalysts were investigated in the present study. The In x Ce 100−x and the In x Zr 100−x mixed oxides catalysts were synthesized via gel-oxalate coprecipitation by varying the atomic ratios between the elements. Subsequently, they were analysed with several characterisation techniques to rationalise the catalytic performances that were obtained by testing the samples in a fixed bed reactor under different reaction conditions. The addition of different amounts Ce or Zr modified the structure and morphology of the samples and promoted the adsorption of CO 2 from 1.8 mmol CO2 ⋅g cat −1 up to 10.6 mmol CO2 ⋅g cat −1. ZrO 2 stabilises the structure and the results suggests that the greater specific activity (168 mg CH3OH ⋅g In2O3 −1⋅h−1 at 300 °C and 2.5 MPa of In 40 Zr 60) could be ascribed to the electronic promotion of Zr. On the contrary, the addition of CeO 2 did not reveal a beneficial effect on the activity. Concerning the stability, In 2 O 3 -ZrO 2 binary oxides seemed to be affected mainly by sintering; whereas In 2 O 3 -CeO 2 were affected by at least three deactivating phenomena: sintering, reduction of In 2 O 3 to metallic indium and coking. Consequently, the deactivation rate of these binary oxides increased from 1.04 ⋅ 10−2 h−1 of the In 100 to 4.13 ⋅ 10−2 h−1 of the In 40 Ce 60. [Display omitted] • CeO 2 and ZrO 2 modify the morphology and boost the CO 2 adsorption rate. • The electronic promotion effect of Zr enhances the methanol synthesis from CO 2. • ZrO 2 stabilises the structure and mitigates the deactivation phenomena. • CeO 2 increases the reducibility of the samples without stabilising the structure. • In 2 O 3 -CeO 2 samples are affected by sintering, formation of metallic In and coking. [ABSTRACT FROM AUTHOR]

Sustainable aviation fuel (SAF) production is one of the strategies to guarantee an environmental-friendly development of the aviation sector. This work evaluates the technical, economic and environmental feasibility of obtaining SAFs by hydrogenation of vegetable oils thanks to in-situ hydrogen production via aqueous phase reforming (APR) of glycerol by-product. The novel implementation of APR would avoid the environmental burden of conventional fossil-derived hydrogen production, as well as intermittency and storage issues related to the use of RES-based (renewable energy sources) electrolysers. The conceptual design of a conventional and advanced (APR-aided) biorefinery was performed, considering a standard plant capacity equal to 180 ktonne/y of palm oil. For the advanced scenario, the feed underwent hydrolysis into glycerol and fatty acids; hence, the former was subjected to APR to provide hydrogen, which was further used in the hydrotreatment reactor where the fatty acids were deoxygenated. The techno-economic results showed that APR implementation led to a slight increase of the fixed capital investment by 6.6% compared to the conventional one, while direct manufacturing costs decreased by 22%. In order to get a 10% internal rate of return, the minimum fuel selling price was found equal to 1.84 $/kg, which is 17% lower than the one derived from conventional configurations (2.20 $/kg). The life-cycle GHG emission assessment showed that the carbon footprint of the advanced scenario was equal to ca. 12 g CO 2 /MJ SAF , i.e., 54% lower than the conventional one (considering an energy-based allocation). The sensitivity analysis pointed out that the cost of the feedstock, SAF yield and the chosen plant size are keys parameters for the marketability of this biorefinery, while the energy price has a negligible impact; moreover, the source of hydrogen has significant consequences on the environmental footprint of the plant. Finally, possible uncertainties for both scenarios were undertaken via Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

Removing pollutants for indoor air purification is a key point to ensure the health and well-being of people in confined environments. This work aims to provide new insight into the development of promising manganese oxide catalysts. The effects of different crystalline phases (MnO 2 and Mn 2 O 3) and the role of redox properties and structural defects were investigated to abate indoor pollutants at mild temperatures. These materials were extensively characterized through complementary techniques and catalytic tests were performed to oxidize 100 ppm of CO, ethylene, or propylene. The most promising catalyst was obtained through solution combustion synthesis, achieving total removal at 118, 222, and 172 °C, respectively, with the highest oxidation rate (2.41, 0.88, and 2.47 μmolg−1s−1) and lowest activation energy (50, 32, and 45 kJmol−1) for the three molecules. The synergy between crystalline phases enhanced the catalytic performance and their distribution in the structure was a crucial parameter affecting the number of structural defects. [Display omitted] • Solution combustion synthesis leads to the formation of highly defective structures. • Uncommon bipyramidal morphology was developed without any surfactants or templates. • Superior enhanced catalytic behavior of MnO 2 compared to Mn 2 O 3. • New insight into the role of De Wolff structural defects in oxidizing CO and VOCs. • Great stability in the presence of moisture and after 8 h under reaction conditions. [ABSTRACT FROM AUTHOR]

The catalytic performance of a Ni/Al hydrotalcite derived catalyst for CO 2 methanation was analysed under different operating conditions. The as synthesized sample has been characterized through atomic adsorption spectroscopy (AAS) X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, temperature programmed reduction (TPR) and CO chemisorption. Experimental investigation was carried out at atmospheric pressure by varying the reactor bed temperature (within the range 270–390 °C), the H 2 /CO 2 feed ratio and the reactant flow rate. The impact of methanation products on the reaction rate was also analysed by co-feeding reactants with steam and methane. Stability tests were also performed, showing a good catalytic performance of the hydrotalcite-derived catalyst over time. Different kinetic rate expressions were then developed starting from experimental results. Power law, power law with an inhibition term and Langmuir-Hinshelwood (LH) approach were tested and compared. The methanation reaction was first modelled by considering the Sabatier reaction. Then, the reverse water-gas shift (RWGS) was also added to account for the presence/formation of CO. A nonlinear regression analysis was performed with the aim of finding kinetic parameters values allowing the minimization of the discrepancy between measured and calculated values of the CH 4 yield (or CO 2 conversion). Results showed a better fitting of experimental data by using the LH expression and the power law (with inhibition influence of adsorbed water or hydroxyl). Main transport criteria were finally checked to evaluate whether operating conditions have been chosen properly in order to study the intrinsic reaction kinetics. [ABSTRACT FROM AUTHOR]

Generally, the thickness of thick metallic plates is measured by exploitation of some physical phenomenon outside of eddy currents which are naturally limited for thin plates with respect to the skin effect. Indeed, it is the capacitive or ultrasound sensors which are the commonly used for thick plates. This paper proposes an alternative for thickness evaluation of thick metallic plates using eddy currents. The measurement system consists mainly of two eddy current sensors, an impedance analyzer LCR-meter and a personnel computer equipped with the Labview software. The plate we want to measure its thick thickness is placed between the two sensors. The proposed measurement procedure is based on lift-offs evaluation of a bi-eddy current sensor. The system has been verified and validated with success using several thick aluminum plates. The realized experimental setup can be used for online thickness measurement in some industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Analysis of the reuse of CO 2 from a waste incinerator in a power-to-gas system. • Different carbon capture and electrolysis technologies are considered. • Detailed modelling of all sections of the power-to-gas system is performed. • KPIs are presented to investigate the energy and environmental performance. • A comparative assessment of the different power-to-gas configurations is provided. Power-to-gas (PtG) and carbon capture and utilisation are expected to play a key role in promoting a sustainable energy transition. In this work, a detailed energy analysis of a complete PtG system integrated with a real waste incinerator is performed. A fraction of the renewable electricity and heat produced by the waste incinerator is used in the PtG system to produce hydrogen, which is further converted into SNG by methanation with CO 2 recovered from the plant flue gases. A PtG plant able to produce up to 500 m3/h of SNG is considered. A total of six different plant configurations are analysed, obtained by the combination of different electrolysis and post-combustion carbon capture technologies. Specifically, alkaline and PEM electrolysers are considered for the production of hydrogen, while absorption with monoethanolamine solution, absorption with monoethanolamine and ionic liquid solution, and temperature swing adsorption with solid sorbent are selected for carbon capture. The main sections of the PtG system are modelled and the performance of the overall system is evaluated by computing key performance indicators, such as the global energy efficiency and the Specific Plant Energy Consumption for CO 2 Avoided (SPECCA). Special attention is also paid to the thermal integration between the methanation unit and the carbon capture unit. The heat produced during the methanation process is sufficient to cover the entire heat demand of the CO 2 capture unit in almost all configurations investigated. In particular, thermal integration increases the global energy efficiency by 5–9% and reduces the SPECCA indicator by 5–8%. Considering the thermally integrated configurations, the global energy efficiency is estimated to be between 44.6% and 46.7%, while the SPECCA value ranges from 40.5 MJ/kg to 42.4 MJ/kg. Finally, some technical considerations are given, including the quality of SNG produced and the degradation phenomena in the considered technologies. [ABSTRACT FROM AUTHOR]

Copper-ceria mixed oxides are widely considered promising catalysts for oxidation reactions, especially when the participation of lattice oxygen is required. However, the mechanistic understanding of these catalytic systems is still incomplete, due to their considerable complexity. In fact, copper doping of ceria results in the formation of a significant number of different interacting sites in continuous evolution during the catalytic processes. In the present study, pure and Cu-doped ceria samples were deeply investigated through combined spectroscopic techniques, i.e. XPS, EPR, and in situ FTIR and Raman spectroscopy. Through this systematic approach, the copper sites and lattice defects responsible for the enhanced CO oxidation activity of doped ceria were elucidated. Superficial Cu+ species and small Cu0 clusters promote the adsorption of CO at low temperature, while isolated Cu2+ monomers and dimers well-dispersed in the ceria matrix foster lattice oxygen mobility, involving the sub-surface in the redox phenomena. Consequently, the structure of Cu-doped ceria undergoes substantial modifications throughout CO oxidation in the absence of O 2 , with the formation of oxygen vacancy clusters. Anyway, these changes are reversible, and structural reorganization in the presence of O 2 can occur even at room temperature. The excellent performance of Cu-doped ceria eventually stems from the effective cooperation among the different catalytic sites in the mixed oxide. [Display omitted] • The different defects and Cu sites in doped ceria are complementarily investigated. • Cu+ sites and small Cu0 clusters at the catalyst surface enhance CO adsorption. • Isolated Cu2+ monomers and dimers in the CeO 2 matrix foster lattice oxygen mobility. • Clusters of oxygen vacancies may form when the oxygen demand at the surface is high. • The effective cooperation of the different sites promotes ceria catalytic activity. [ABSTRACT FROM AUTHOR]

A sample of pure CeO 2 and two samples of Fe-doped CeO 2 containing either 3 or 6 at.% Fe were obtained by microwave assisted combustion synthesis. The powders were extensively characterized by several techniques and tested as catalysts for both CO oxidation and soot combustion. As-synthesized CeO 2 nanoparticles have a mostly squared shape and size well below 100 nm; they are characterized by the presence of surface Ce 3+ species likely due to the occurrence of very defective ceria crystalline phases, as revealed by HR-TEM. Oxidation at 400 °C leads to the formation of a hydroxyls-rich surface, with several types of OH groups related to both Ce 4+ and Ce 3+ species; reduction in H 2 at mild temperature (200 °C) leads both to reduction of surface Ce 4+ to Ce 3+ and formation of new OH groups. With respect to CeO 2 nanoparticles, Fe-doped ones have, as a whole, a larger size and less abundant surface OH species. A core-shell structure is inferred where Fe is mostly present in the shell, both in a secondary phase (CeFeO 3 ) and as a dopant, finally lowering the band gap of the material. The presence of Fe improved samples reducibility, as shown by the lowering of the onset of temperature programmed reduction. Catalytic tests of CO oxidation showed that surface Fe species significantly improve the catalytic performance of the samples, by lowering the onset of CO conversion to CO 2 especially at low Fe content ( i.e. 3 at.%), whereas at 6 at.% Fe loading, the preferential formation of the secondary phase CeFeO 3 occurs, finally lowering the CO conversion with respect to the sample containing 3 at.% Fe. Conversely, the soot combustion activity was higher for pure CeO 2 nanoparticles, likely due to their smaller size, which increases the amount of solid–solid contact points between soot and the catalyst. However, a positive effect of the presence of surface Fe species on the catalytic activity towards soot combustion was observed, as well. [ABSTRACT FROM AUTHOR]

Solid state ion exchange was performed for the successful introduction of Fe cations in the small pore CHA structured SSZ-13 zeolite. The produced catalysts were characterized by IR and UV-Vis spectroscopies and thermally programmed reaction techniques to probe the Fe sites formed during the exchange and the catalytic activity for the NO x SCR reaction. The results indicate that highly dispersed and heterogeneous Fe sites are formed, and the type depends on the Al distribution in the zeolite. Dimeric Fe species are formed preferentially at the start of the exchange on the 6- and 8-member rings that contain at least two Al exchange sites and once these sites are fully saturated the Fe is exchanged as isolated cations. [Display omitted] • Through SSIE Fe2 + cations can be reliably introduced in small pore SSZ-13 zeolite. • Absence of O2 and using the NH4 + form of the zeolite during SSIE was critical. • SSIE of Fe proceeded in ordered fashion, likely influenced by the Al distribution. • Final product contained highly heterogeneous Fe distribution. • High catalytic activity for SCR of NOx. [ABSTRACT FROM AUTHOR]

Ceria-based catalysts with different topological and textural properties have been prepared to study the role of the soot-catalyst contact on the soot oxidation reaction. The physico-chemical features of the catalysts have been investigated by means of complementary techniques, such as powder XRD, N 2 physisorption at −196 °C, optical microscopy at variable temperature, FESEM, TEM, and thermogravimetric analysis. As a whole, the best catalytic activity has been obtained with the CeO 2 -nanocubes (denoted to as “Ce-NC”) because of their higher intrinsic reactivity. On the other hand, high-surface area materials prepared by the cerium nitrate decomposition (denoted to as “Ce-ND”) or hydrothermal route (CeO 2 -stars, referred to as “Ce-SAS”) resulted less effective toward the soot combustion, confirming the surface-sensitivity for this reaction. Moreover, it has been proven a higher dependence of the oxidation activity on the catalyst-to-soot ratio (wt./wt.) for the nanostructured catalyst (Ce-NC) exhibiting the lowest BET specific surface area (S BET = 4 m 2 g −1 ). On the other hand, the accessible (real) surface area, at variance of the BET surface area, seems to play a relevant role for this solid–solid reaction mediated by gas-phase oxygen. [ABSTRACT FROM AUTHOR]

The present study reports an improved design for Pd/Ce-Pr catalysts. Pd-impregnated nanostructured ceria-praseodymia catalysts with different compositions were comprehensively characterized and tested for dry and wet methane oxidation. The strong PdO-PrO x interaction, detected via XRD, TPR/TPO, Raman and HRTEM analyses, retains Pd mainly in its oxidized form in the materials with high praseodymium content, thus resulting in a lower activity. Conversely, the introduction of a limited amount of Pr in ceria allows to obtain a more active catalyst (2% of Pd supported on a mixed oxide with 10% of Pr) than the typical Pd/CeO 2 systems. Hence, the simultaneous presence of Pd in its reduced and oxidized forms results to be a key factor for high activity. Additionally, the higher hydrophobicity of this sample, investigated through NMR and in situ FTIR, markedly reduces the H 2 O inhibition effect typical of Pd-based materials, paving the way for using this system in real applications. [Display omitted] • Pd on nanostructured Ce-Pr oxides were studied for the complete methane oxidation. • The effect of the support composition on the Pd oxidation state was investigated. • A small amount of Pr (Pd/Ce90Pr10) was promising for dry and wet methane oxidation. • Pd/Ce90Pr10 higher activity was related to optimized hydrophobicity/hydrophilicity. [ABSTRACT FROM AUTHOR]

Commercial Mn 2 O 3 , Mn 3 O 4 and MnO 2 and the same after thermal or ball-milling treatments have been examined as catalysts for the photocatalytic water oxidation reaction, using [Ru(bpy) 3 ] 2+ as photosensitizer and S 2 O 8 2− as sacrificial electron acceptor. Tests were performed in a bubbling reactor, allowing the calculation of the actual rate of O 2 evolution as a function of time from raw data (oxygen flow, concentration of dissolved oxygen, DO) through a model able to take into account mass transfer phenomena Hernández et al. [19]. A few parameters are proposed for measuring activity, and comparison among them is made. The activity per unit mass of commercial samples is Mn 2 O 3 > MnO 2 > Mn 3 O 4 , in agreement with the literature. Increase in the surface area brought about by milling correspond, as expected, to a steady increase in activity in the case of Mn 3 O 4 , whereas had no effect with Mn 2 O 3 . The markedly higher specific surface of Mn 2 O 3 and Mn 3 O 4 samples obtained by thermal treatment of MnO 2 and a home-made sample, respectively, correspond surprisingly to activities lower than low surface area ball milled samples. Reasons for this are proposed to be a different nature of the surfaces arrived at, because of the different preparation route. A similar study of the effect of surface area for MnO 2 specimens is prevented by their largely amorphous nature. Comparison of present data with those already reported gives further support to the bounty of the model taking into account mass transfer. [ABSTRACT FROM AUTHOR]

There is an ever-increasing attention directed to the development of solar fuels by photo-electrochemical water splitting, given the inexhaustible availability of solar energy. The water oxidation half-reaction is a critical step for the overall water splitting reaction, and the development of suitable photoanodes is therefore required. The present research work focuses on bismuth vanadate thin films’ deposition on FTO glass electrodes, through the dip coating technique, and discusses the influence of the film preparation technique on the electrode's photo-electrochemical performance. The bismuth vanadate thin films were synthesized with thicknesses ranging from 60 to 210 nm, depending on a number of dip coatings from 2 to 15. The structural and optical characterization of the films showed that monoclinic scheelite-type phase was obtained in all samples, with crystal sizes ranging from 24 to 65 nm, at increasing film thicknesses, and corresponding band gaps between 2.55 and 2.35 eV. A maximum photo-current density of about 0.57 mA cm −2 at 1.23 V vs. RHE under sunlight illumination was obtained for an electrode thickness of 160 nm. The electrochemical impedance spectroscopy elucidated the transport mechanisms occurring at the electrolyte–electrode interface, as well as inside the film. The estimation of the equivalent circuit parameters showed that an increasing film thickness decreased the resistance associated to the charge transfer between the electrolyte and the electrode (from 1100 to 450 Ω, from 60 to 160 nm layer thickness, respectively), given the higher number of active sites involved in the reaction. However, excessive film thicknesses increase the probability of charge recombination within the film and, in the specific case here investigated, can also be associated to film imperfections arising from several deposition-calcination cycles, which further act as traps. These concurring phenomena are of high relevance to isolate the rate-determining step of the water oxidation half-reaction, in the perspective of an optimization of bismuth vanadate film coating on FTO to obtain photo anodes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Physicochemical parameters affecting the photochemical water oxidation activity. [•] (NH4)2CO3 used to influence preferential crystal growth along (040) facets. [•] Mathematical model to estimate more accurately the O2 production rate. [•] Morphology optimization of BiVO4 to produce a highly active photocatalyst. [ABSTRACT FROM AUTHOR]

CaCO 3 particles are widely employed in different fields due to their properties, such as tunable size and morphology, tailored porosity and surface area, biocompatibility and nontoxicity. Therefore, many researchers have studied and developed several synthesis methods, even with and without additives. Among them, the synthesis of CaCO 3 through the carbonation method can be considered the most eco-friendly and innovative one. A continuously growing research effort has been devoted to this method since it could represent a potential process for CO 2 mitigation. Furthermore, this method could involve the use of several wastes as raw inputs, such as flue gases, distiller waste, steel converter slag, oil shale ash, waste concrete, etc., which would reduce the environmental impact of the process. This review article is mainly focused on this approach and the process parameters that affect the yield, particle size, morphology and crystalline phase. The control of size and morphology through different experimental setups and the use of additives is also described. Furthermore, the current uses of CaCO 3 in different fields, such as material filling, papermaking, medicine and personal care, are discussed, and its role in these applications is reported. [Display omitted] [ABSTRACT FROM AUTHOR]

• Enabling technologies are potential tools for process intensification of lignin. • Mechanochemical and cavitation treatments are the most effective pre-treatment for biomass. • Membrane technology is a valid means for the fractionation of extracted lignin. • Microwaves are more suitable as efficient device for lignin depolymerization. • Techno-economic analysis of unconventional technologies is crucial to scale up. Nowadays, the increasing concern about the declining fossil fuel reserves and the environmental impact derived from their use has put considerable interest in lignocellulose exploitation as a renewable source of biofuels and biomaterials, according to the biorefinery concept. Several processes and technologies have been extensively studied in order to optimize biomass treatments aiming to enhance the recovery of its main products: cellulose, hemicelluloses and lignin. Lignin is, in fact, considered a valid substitute to petroleum as a source of aromatics, thanks to its abundance in nature. However, its complex and highly resistant structure limits its further applications, therefore, lignin upgrading is considered extremely challenging: various processes have been developed in recent years, but their feasibility at industrial scale still represents a bottleneck. Recently, process intensification has gained considerable attention in the design of sustainable procedures for lignin valorization. In particular, non-conventional technologies such as Ball milling, Ultrasounds (US) and Microwaves (MW) have recently shown promising results in biomass exploitation, thanks to their ability in generating specific high-energy microenvironments which could enhance process efficiency: mechanochemical and US activation have been mostly applied to biomass pre-treatment, in order to separate its components and enhance lignin extraction yield, while MW have been exploited as a means for lignin depolymerization, achieving higher yields of aromatics in milder reaction conditions. However further efforts should be done to improve profitability through new processes, aiming to reduce the cost associated to bio-derived products. In the present review, recent approaches to lignin valorization are discussed, focusing on new alternative methodologies for process intensification, besides their challenges and feasibility at industrial scale. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • CaCO 3 from CO 2 and Ca+ salts can be a valuable product within a cement factory. • Ca+ sourced from wastes implies the presence of other ions (Na+, NH 4 + and K+). • The presence of foreign ions can affect the precipitation of the CaCO 3 crystals. • NH 4 + favors the nucleation of metastable vaterite crystals over stable calcite. • Calcite growth rate is enhanced in the presence of Na+ and K+ ions over NH 4 +. The aim of this work is to study the effect of the presence of different monovalent ions (Na+, NH 4 + and K+) on the nucleation and growth rates of CaCO 3 precipitation. There is currently great interest in the precipitation of CaCO 3 particles reusing CO 2 rich flue gases and calcium-rich wastes, which implies the presence of foreign ions that can affect the crystallization process. Unseeded and seeded tests were carried out in a batch system to estimate the nucleation and growth kinetics, respectively. Tests with Na 2 CO 3 and CaCl 2 as precursors led to the classical calcite crystallization mechanism via vaterite formation at high supersaturations. On the other hand, the use of (NH 4) 2 CO 3 entailed lower pH and the presence of NH 4 +, which stabilized the vaterite and avoided its transformation into stable calcite crystals. Thus, faster nucleation kinetics by using Na 2 CO 3 were obtained. To estimate the growth rate, tests with two initial seed loadings and types (micro and nano seed) were performed. The growth rate increased with the crystal size and decreased with the magma density. The results indicate that the ion effect on the growth rate seems to be related to the ionic radius of the foreign ion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Methanol is firstly produced by CO 2 electroreduction with a CuO/ZnO/Al 2 O 3 catalyst. • CO 2 -to-methanol conversion is scaled-up from lab data process simulation results. • Electrocatalytic CO 2 conversion is sustainable with 90% of FE and 200 mA/cm2. • CO 2 -to-Methanol could be economically competitive at productivity >20 kg/h methanol. • The carbon footprint is 62% lower for both processes using 100% of renewable energy. Electrocatalytic (EC) and thermocatalytic (TC) conversion of CO 2 to methanol are promising carbon capture and utilization technologies. Herein, these CO 2 -to-methanol conversion processes are analysed in terms of technical, environmental and economic feasibility. To this purpose, the catalytic performance of the same catalyst (CuO/ZnO/Al 2 O 3) was evaluated in both EC and TC processes. Here is showed for the first time that this catalyst is (apart from TC route) also able to generate methanol through CO 2 EC reduction. This work presents lab scale tests, scaled-up simulations and evaluates the environmental and economic performance of these processes. The carbon footprint of the TC and EC processes, scaled-up to the same productivity of ~ 3 kg/h methanol, scored ~ 8 kg CO2 eq /kg CH3OH. Strategies to reduce this impact are presented, such as improving the current density of the EC cell (i.e. 200 mA/cm2 results in a reduction of 68% to 2.72 kg CO2 eq /kg CH3OH) and the availability of 100% renewable electricity (saving up to 62% carbon footprint of both processes). Considering an effective allocation of the methanol productivity on a real market scenario, both the TC and EC processes would start to be economically competitive at methanol productivities > 19.1 kg/h and 3.3 kg/h, respectively. Moreover, if O 2 valorisation, a low price of the renewable electricity and a carbon tax are considered, the economic profitability will rise; e.g. the minimum levelised cost of product (LCOP of 1.45 €/kg and 1.67 €/kg, respectively) could be reduced by 53%. Finally, our results pointed out that the CO 2 electroreduction process must be optimized (e.g. improving catalysts performance and EC cell design reducing mass transfer limitations) to achieve industrially relevant rates and the maturity of the thermocatalytic technology. [ABSTRACT FROM AUTHOR]

• Cu-SSZ-13 was mixed with CeO 2 -SnO 2 for enhanced resistance to hydrocarbon poisoning. • Synergy for C 3 H 6 oxidation between the two components was observed. • NO and C 3 H 6 oxidation were competitive over Cu-SSZ-13 but cooperative over Composite. • No negative effect on NO x conversion or selectivity was observed in the Composite. The state-of-the-art Cu-SSZ-13 was mixed with CeO 2 -SnO 2 to form a Composite catalyst which was resistant towards hydrocarbon poisoning of the NH 3 -mediated NO x -SCR reaction. The Composite was prepared via a solid-state synthesis through ball milling, which did not influence the final morphology. The resistance towards propylene poisoning was remarkably enhanced as the NO x conversion over the Composite catalyst decreased only 9% compared to 40 % over the unmodified Cu-SSZ-13. Transient and dynamic reactivity studies showed that the coke formed during the C 3 H 6 protolytic polymerization was dispersed inside the zeolite pores and the addition of CeO 2 -SnO 2 did not prevent its formation nor enhance its oxidation with O 2. The ion-exchanged Cu was the principal active component for the coke and hydrocarbon oxidation and the hydrocarbon poisoning prevention was attributed to the complex interaction between the three primary active sites (Cu – CeO 2 -SnO 2 – protonic sites). Propylene oxidation over Cu-SSZ-13 was inhibited when NO was included in the reaction stream, while over the H-Composite (mixture of H-SSZ-13 and CeO 2 -SnO 2) it had the reverse effect, since C 3 H 6 and NO x oxidation did not compete for the same active sites on CeO 2 -SnO 2. Basing on reactivity studies coupled with IR analysis, a deactivation and poisoning prevention mechanism was proposed, whereby the HONO/nitrate intermediates formed over the CeO 2 -SnO 2 catalyst re-activated the zeolitic copper for the SCR reaction. [ABSTRACT FROM AUTHOR]

Calcium carbonate nanoparticles (CaCO 3 NPs) derived from CO 2 are evaluated in terms of toxicological profile both in vitro (cells) and in vivo (zebrafish). The toxicity in cells is investigated as cell viability, while in zebrafish using different biological parameters (i.e. survival). • CaCO 3 NPs are purely cubic calcite with a narrow particle size distribution. • CaCO 3 NPs do not affect the cell viability of normal (NIH 3T3) and cancer (MCF7) cells. • High concentrations of CaCO 3 NPs exhibit no genotoxicity against NIH 3T3 and MCF7 cells. • CaCO 3 NPs have no developmental toxicity to zebrafish embryos. Calcium carbonate nanoparticles (CaCO 3 NPs) derived from CO 2 are promising materials for different industrial applications. It is imperative to understand their toxicological profile in biological systems as the human and environmental exposures to CaCO 3 NPs increases with growing production. Here, we analyse the cytotoxicity of CaCO 3 NPs synthesized from a CaO slurry on two cell lines, and in vivo on zebrafish (Danio Rerio). Our results demonstrate the CaCO 3 NPs in vitro safety as they do not cause cell death or genotoxicity. Moreover, zebrafish treated with CaCO 3 NPs develop without any abnormalities, confirming the safety and biocompatibility of this nanomaterial. [ABSTRACT FROM AUTHOR]

• Compounds representatives of biorefinery streams were tested by APR. • Several molecules were investigated for the first time. • Binary and ternary mixtures were explored to evaluate collateral effects. • Acetic acid was found as a key intermediate/by-product of APR. An extensive screening of representative molecules of a post-hydrothermal process side stream has been performed with the aim of producing a gas mixture rich in hydrogen by catalytic aqueous phase reforming. The survey enlightens possible routes of valorisation of these by-products, scarcely investigated with other processes so far. The influence of reaction temperature was studied in the 230–270 °C range, looking at both the composition of the gas phase and the characterization of the liquid products. Indeed, the information coming from the condensed phase may provide relevant insights on the components that are not easily reformed, and that should be studied to improve the performance of the process. Binary and ternary mixtures of four selected compounds were tested to investigate synergistic and inhibiting effects, going towards the direction of a real biorefinery stream. The spent alumina-supported catalyst was characterized, outlining possible deactivation mechanisms of the catalytic system, and reused in two successive tests. [ABSTRACT FROM AUTHOR]

Copper-exchanged ZSM-5 (Cu-ZSM-5) is a promising catalyst thanks to the Cu redox pair. A particular feature of this material consists in the presence of spontaneous isothermal oscillations which take place during N 2 O decomposition reaction, depending on the operating conditions. In the present work, a set of five Cu-ZSM-5 catalysts was synthesised by three procedures and three different copper precursor concentrations: i) wet impregnation, ii) single ion exchange, and iii) double ion exchange. Catalytic tests revealed that the ion-exchanged samples exhibit a low catalytic activity and no oscillatory behaviour, except for the twice-exchanged sample which achieves an average N 2 O conversion of 26 % at 400 °C. Conversely, the impregnated samples reach higher levels of N 2 O conversion (66 % for Cu 5 ZSM5_WI and 72 % for Cu 10 ZSM5_WI) and demonstrate a similar oscillating pattern. Further investigations disclosed that the most active catalysts, characterised by the presence of oscillatory behaviour, have more abundant and easily reducible copper species (ICP, EDX and H 2 -TPR) which interact better with the zeolitic support (FT-IR). Catalytic tests under a long time on stream (TOS) suggest that either self-organised patterns or deterministic chaos can be achieved during the reaction, depending on the operating conditions, such as temperature and contact time., (© 2024 Wiley-VCH GmbH.)

Many studies have clearly established that chronic psychosocial stress may sustainably worsen glycemic control in patients with type 1 diabetes mellitus (T1DMM), thus promoting diabetes complications. Chronic psychosocial stress may be due to: i) the long-term accumulation of stressful life events that require readjustment on the part of the individual (loosing friends, changing schools), and/or ii) exposure to severe chronic stressors (persistent difficulties and adversities of life). Whatever the reason, many studies have clearly established a positive correlation between chronic psychosocial stress and HbA1c levels. However, a small fraction of patients is minimally affected or not affected at all by chronic psychosocial stress. Conversely, positive life events can substantially improve glycemic control. Recent evidence suggests the existence of subpopulations that differ in personality traits, neurohormonal regulatory responses, and food intake behavior (increased or decreased). Better characterization of the clinical and neurohormonal differences between these subpopulations may help develop personalized treatment strategies in the future. In the near future, psychotherapeutic support and automated insulin delivery (AID) could alleviate chronic stress, prevent worsening glycemic control, and ease the burden of diabetes., Competing Interests: Declaration of Competing Interest SF has received personal compensation for board participation and speaking fees from Novo Nordisk, Roche Diagnostics, Lifescan, Sanofi, Diabeloop and Eli Lilly, received Research support from MSD outside of this work; SF is employed by CERITD and is a shareholder of Diabeloop. PS has received honoraria for her participation in advisory boards for Eli-Lilly, Novo-Nordisk, Ypsomed, Orkyn, Timkl, and participation in symposia organized by Novo-Nordisk, Abbott Diabetes Care, Roche, Sanofi, and Insulet outside the submitted work. GC is employed by CERITD and is a shareholder of Diabeloop. LO and SB are employed by CERITD and have no conflict of interest to declare. PL has no conflict of interest to declare. The Epistress 1 study was carried out with CERITD's own funds., (Copyright © 2023. Published by Elsevier Masson SAS.)

In skeletal muscle, chronic oxygen depletion induces a disturbance leading to muscle atrophy. Mechanical stress (physical exercise) and nutritional supplement therapy are commonly used against loss of muscle mass and undernutrition in hypoxia, while oxygenation therapy is preferentially used to counteract muscle fatigue and exercise intolerance. However, the impact of oxygenation on skeletal muscle cells remains poorly understood, in particular on signalling pathways regulating protein balance. Thus, we investigated the effects of each separated treatment (mechanical stress, nutritional supplementation and oxygenation therapy) on intracellular pathways involved in protein synthesis and degradation that are imbalanced in skeletal muscle cells atrophy resulting from hypoxia. Myotubes under hypoxia were treated by electrical stimulation, amino acids supplement or oxygenation period. Signalling pathways involved in protein synthesis (PI3K-Akt-mTOR) and degradation (FoxO1 and FoxO3a) were investigated, so as autophagy, ubiquitin-proteasome system and myotube morphology. Electrical stimulation and oxygenation treatment resulted in higher myotube diameter, myogenic fusion index and myotubes density until 48 h post-treatment compared to untreated hypoxic myotubes. Both treatments also induced inhibition of FoxO3a and decreased activity of ubiquitin-proteasome system; however, their impact on protein synthesis pathway was specific for each one. Indeed, electrical stimulation impacted upstream proteins to mTOR (i.e., Akt) while oxygenation treatment activated downstream targets of mTOR (i.e., 4E-BP1 and P70S6K). In contrast, amino acid supplementation had very few effects on myotube morphology nor on protein homeostasis. This study demonstrated that electrical stimulation or oxygenation period are two effective treatments to fight against hypoxia-induced muscle atrophy, acting through different molecular adaptations., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The development of efficient catalysts is one of the main challenges in CO 2 conversion to valuable chemicals and fuels. Herein, inspired by the knowledge of the thermocatalytic (TC) processes, Cu/ZnO and bare Cu catalysts enriched with Cu +1 were studied to convert CO 2 via the electrocatalytic (EC) pathway. Integrating Cu with ZnO (a CO-generation catalyst) is a strategy explored in the EC CO 2 reduction to reduce the kinetic barrier and enhance C-C coupling to obtain C 2+ chemicals and energy carriers. Herein, ethanol was produced with the Cu/ZnO catalyst, reaching a productivity of about 5.27 mmol·g cat -1 ·h -1 in a liquid-phase configuration at ambient conditions. In contrast, bare copper preferentially produced C 1 products like formate and methanol. During CO 2 hydrogenation, a methanol selectivity close to 100% was achieved with the Cu/ZnO catalysts at 200 °C, a value that decreased at higher temperatures (i.e., 23% at 300 °C) because of thermodynamic limitations. The methanol productivity increased to approximately 1.4 mmol·g cat -1 ·h -1 at 300 °C. Ex situ characterizations after testing confirmed the potential of adding ZnO in Cu-based materials to stabilize the Cu 1+ /Cu 0 interface at the electrocatalyst surface because of Zn and O enrichment by an amorphous zinc oxide matrix; while in the TC process, Cu 0 and crystalline ZnO prevailed under CO 2 hydrogenation conditions. It is envisioned that the lower *CO binding energy at the Cu 0 catalyst surface in the TC process than in the Cu 1+ present in the EC one leads to preferential CO and methanol production in the TC system. Instead, our EC results revealed that an optimum local CO production at the ZnO surface in tandem with a high amount of superficial Cu 1+ + Cu 0 species induces ethanol formation by ensuring an appropriate local amount of *CO intermediates and their further dimerization to generate C 2+ products. Optimizing the ZnO loading on Cu is proposed to tune the catalyst surface properties and the formation of more reduced CO 2 conversion products.

Hypoxia, occurring in several pathologies, has deleterious effects on skeletal muscle, in particular on protein homeostasis. Different induction methods of hypoxia are commonly used in cellular models to investigate the alterations of muscular function consecutive to hypoxic stress. However, a consensus is not clearly established concerning hypoxia induction methodology. Our aim was to compare oxygen deprivation with chemically induced hypoxia using cobalt chloride (CoCl 2 ) or desferrioxamine (DFO) on C2C12 myotubes which were either cultured in hypoxia chamber at an oxygen level of 4% or treated with CoCl 2 or DFO. For each method of hypoxia induction, we determined their impact on muscle cell morphology and on expression or activation status of key signaling proteins of synthesis and degradation pathways. The expression of HIF-1α increased whatever the method of hypoxia induction. Myotube diameter and protein content decreased exclusively for C2C12 myotubes submitted to physiological hypoxia (4% O 2 ) or treated with CoCl 2 . Results were correlated with a hypophosphorylation of key proteins regulated synthesis pathway (Akt, GSK3-β and P70S6K). Similarly, the phosphorylation of FoxO1 decreased and the autophagy-related LC3-II was overexpressed with 4% O 2 and CoCl 2 conditions. Our results demonstrated that in vitro oxygen deprivation and the use of mimetic agent such as CoCl 2 , unlike DFO, induced similar responses on myotube morphology and atrophy/hypertrophy markers. Thus, physiological hypoxia or its artificial induction using CoCl 2 can be used to understand finely the molecular changes in skeletal muscle cells and to evaluate new therapeutics for hypoxia-related muscle disorders.

The aim of this work is to study the activity of novel TiO 2 -based photocatalysts doped with either phosphorus or zirconium under a UV-Vis source. A set of mesoporous catalysts was prepared by the direct synthesis: TiO 2 _A and TiO 2 _B (titanium oxide synthesized by two different procedures), P-TiO 2 and Zr-TiO 2 (binary oxides with either nonmetal or metal into the TiO 2 framework). Complementary characterizations (N 2 physisorption at 77 K, X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) analysis, X-ray Photoelectron Spectroscopy (XPS), and (DR)UV-Vis spectroscopy) were used to investigate the physicochemical properties of the prepared catalysts. Then, the photocatalysts were tested for the oxidation of propylene and ethylene under UV-Vis light. As a result, the most promising catalyst for both the propylene and ethylene oxidation reactions was the P-TiO 2 (propylene conversion = 27.8% and ethylene conversion = 13%, TOS = 3 h), thus confirming the beneficial effect of P-doping into the TiO 2 framework on the photocatalytic activity.

To reduce the emissions of internal combustion engines, ceria-based catalysts have been widely investigated as possible alternatives to the more expensive noble metals. In the present work, a set of four different ceria-based materials was prepared via hydrothermal synthesis, studying the effect of Cu and Mn as dopants both in binary and ternary oxides. In situ Raman analyses were carried out to monitor the behaviour of defect sites throughout thermal cycles and during the soot oxidation reaction. Despite ceria doped with 5% of Cu featured the highest specific surface area, reducibility and amount of intrinsic and extrinsic defects, a poor soot oxidation activity was observed through the standard activity tests. This result was confirmed by the calculation of soot conversion curves obtained through a newly proposed procedure, starting from the Raman spectra collected during the in situ tests. Moreover, Raman analyses highlighted that new defectiveness was produced on the Cu-doped catalyst at high temperature, especially after soot conversion, while a slight increase of the defect band and a total reversibility were observed in case of the ternary oxide and pure/Mn-doped ceria, respectively. The major increment was related to the extrinsic defects component; tests carried out in different atmospheres suggested the assignment of this feature to vacancy-free sites containing oxidized doping cations. Its increase at the end of the tests can be an evidence of peroxides and superoxides deactivation on catalysts presenting excessive oxygen vacancy concentrations. Instead, ceria doped with 5% of Mn exhibited the best soot oxidation activity, thanks to an intermediate density of oxygen vacancies and to its well-defined morphology.

A set of ceria, ceria-zirconia (Ce 80 at.%, Zr 20 at.%), ceria-praseodymia (Ce 80 at.%, Pr 20 at.%) and ceria-zirconia-praseodymia (Ce 80 at.%, Zr 10 at.% and Pr 10 at.%) catalysts has been prepared by the solution combustion synthesis (SCS). The effects of Zr and Pr as dopants on ceria have been studied in CO and soot oxidation reactions. All the prepared catalysts have been characterized by complementary techniques, including XRD, FESEM, N2 physisorption at -196 °C, H2-temperature-programmed reduction, and X-ray photoelectron spectroscopy to investigate the relationships between the structure and composition of materials and their catalytic performance. Better results for CO oxidation have been obtained with mixed oxides (performance scale, Ce80Zr10Pr10 > Ce80Zr20 > Ce80Pr20) rather than pure ceria, thus confirming the beneficial role of multicomponent catalysts for this prototypical reaction. Since CO oxidation occurs via a Mars-van Krevelen (MvK)-type mechanism over ceria-based catalysts, it appears that the presence of both Zr and Pr species into the ceria framework improves the oxidation activity, via collective properties, such as electrical conductivity and surface or bulk oxygen anion mobility. On the other hand, this positive effect becomes less prominent in soot oxidation, since the effect of catalyst morphology prevails.

The freezing of the food is one of the most important technological developments for the storage of food in terms of quality and safety. The aim of this work was to study the role of an ice structuring protein (ISP) on freezing-thawing cycles of different solutions and commercial Italian pasta sauces. Ice structuring proteins were related to the modification of the structure of ice. The results showed that the freezing time of an aqueous solution containing the protein was reduced to about 20% with respect to a pure water solution. The same effect was demonstrated in sugar-containing solutions and in lipid-containing sauces. The study proved a specific role of ISP during thawing, inducing a time decrease similar to that of freezing and even more important in the case of tomato-based sauces. This work demonstrated the role of ISP in the freezing-thawing process, showing a significant reduction of processing in the freezing and thawing phase by adding the protein to pure water and different sugar-, salt- and lipid-containing solutions and commercial sauces, with considerable benefits for the food industry in terms of costs and food quality.