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This document describes the dataset of depth (pressure)/temperature profiles collected by means of the AdriFOOS infrastructure in the period 2012–2020 and briefly illustrates the structure of this facility, the oceanographic dataset validation procedures, some of the results achieved, and also lists some possible operational applications. In fact, in the last decade, CNR IRBIM's AdriFOOS has collected an enormous amount of georeferenced oceanographic and catch data through the use of commercial fishing vessels operating in the Adriatic Sea. This information is of the utmost importance to provide data to feed oceanographic models and advance knowledge on climate change, as well as to improve the ecosystem approach to fisheries management.

Generic models for the mean carbon number n̄, H/C ratio β and chain growth probability α, as a function of C5+ selectivity for Fischer–Tropsch reactions, have been developed based on gas analysis data and product mass. These models allow predicting the parameters when detailed compositions of oil and wax are unavailable. Meanwhile, the distribution of individual 2–5 methyl paraffins of iron and cobalt catalysts containing K, Zr and Pt promoters or poisoned by COS and HBr were studied. The chain-length-dependent formation of methyl paraffins was demonstrated on both iron and cobalt catalysts. The fraction of the methyl paraffins produced on an active iron catalyst (15–22%) was 5–7 times higher than that of a cobalt catalyst (1–3%). Ethylidene (CH2CH–M) was proposed as one possible iso-chain growth monomer, based on the higher fraction of 3-methyl product. The effects of the promoters and the poisons on the formation of iso-paraffins and 1-olefin were complicated. K (Fe), Zr and S (Co) improved the formation of 1-olefins and suppressed the formation of iso-paraffins, partly due to the electronic effect (back-donation) of the promoters. Pt inhibited the formation of both 1-olefins and iso-paraffins on a cobalt catalyst. Adding HBr was found to promote the formation of iso-paraffins on an iron catalyst.

Different low-cost cobalt precursors (acetate, chloride) and thermal treatments (air calcination/H2 reduction versus direct H2-activation) were investigated to alter the interaction between cobalt and silica. H2-activated catalysts prepared from cobalt chloride had large Co0 particles (XRD, chemisorption) formed by weak interactions between cobalt chloride and silica (temperature programmed reduction (TPR), TPR with mass spectrometry (TPR-MS), TPR with extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge spectroscopy (XANES) techniques) and retained Cl-blocked active sites, resulting in poor activity. In contrast, unpromoted Co/SiO2 catalysts derived from cobalt acetate had strong interactions between Co species and silica (TPR/TPR-MS, TPR-EXAFS/XANES), adding Pt increased the extent of the Co reduction. For these Pt-promoted catalysts, the reduction of uncalcined catalysts was faster, resulting in larger Co0 clusters (19.5 nm) in comparison with the air-calcined/H2-activated catalyst (7.8 nm). Both catalysts had CO conversions 25% higher than that of the Pt-promoted catalyst prepared in the traditional manner (air calcination/H2 reduction using cobalt nitrate) and three times higher than that of the traditional unpromoted Co/silica catalyst. The retention of residual cobalt carbide (observed in XANES) from cobalt acetate decomposition impacted performance, resulting in a higher C1–C4 selectivity (32.2% for air-calcined and 38.7% for uncalcined) than that of traditional catalysts (17.5–18.6%). The residual carbide also lowered the α-value and olefin/paraffin ratio. Future work will focus on improving selectivity through oxidation–reduction cycles.

Direct reduction of cobalt nitrate versus conventional calcination/reduction treatment was conducted using alumina with identical methodology as previously applied to SiO2 and TiO2. Similar BET surface areas, pore volumes and pore size distributions were obtained for the activated calcined and uncalcined catalysts indicating no significant difference in morphological properties. However, the reducibility slightly increases and Co crystallite size is smaller for activated uncalcined samples. Reduction phenomena were analyzed by TPR-MS and TPR-EXAFS/XANES. Combining these techniques allows an explanation of the complex phenomena occurring during the direct reduction of cobalt nitrate, as both nitrate decomposition and cobalt oxide reduction are involved. Cobalt nitrate species are converted to CoOx intermediates. These species are oxidized by NOX (from nitrate decomposition) to Co3O4 spinel, which is converted to CoO prior to Co0 formation. Noble metals (Pt, Re, Ru and Ag) improve cobalt oxide reducibility, especially for the final reduction step (i.e., CoO to Co0). The effect of direct nitrate reduction on FT activity was investigated using a 1 L CSTR. Activated unpromoted and Pt-promoted uncalcined catalysts achieved higher initial and steady-state CO conversions in comparison to the corresponding calcined catalysts. The best performance was achieved with direct reduction of uncalcined 0.5 %Pt-25 %Co/Al2O3.

The effect that sodium has on Pt/m-ZrO2 catalyst was investigated during ethanol steam reforming (ESR). Sodium doping decreases the catalytic activity, but significantly increases CO2 selectivity, providing a means of improving H2 selectivity. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) results suggest that acetate species are intermediates in the reaction and that their decomposition can follow different routes depending on the catalyst formulation. When Pt/m-ZrO2 is promoted by sodium, decarboxylation is the favored route: forward decomposition of acetate at lower temperatures yields essentially methane and adsorbed carbonate, further decomposing to carbon dioxide. At higher temperature, the methane precursor can be intercepted by the metal for further steam reforming or a separate methane steam reforming catalyst can be used downstream. Decarbonylation is instead favored for the unpromoted catalyst; decarbonylation tends to lower the H2 selectivity of the overall process. Finally, the addition of sodium promotes C–C scission as methane formation is detected at lower temperature by DRIFTS and TPD-MS of ethanol in steam. This is analogous to formate C–H bond breaking in methanol steam reforming, steam-assisted formic acid decomposition, and water-gas shift reactions. In catalytic testing of ESR utilizing a tubular reactor at low temperatures (where steam reforming of CH4 is limited), methane and CO2 selectivities are higher with the Na-promoted catalyst than with the unpromoted catalyst. Thus, promotion of the forward decomposition of acetate route by Na addition is confirmed.

Deuterium tracer studies coupled with kinetic approach were developed to accurately determine the kinetic isotopic effects (KIE) for the CO hydrogenation and the formations of CO2, CH4 and light hydrocarbons (C2-C4) over iron, cobalt and ruthenium catalysts. Pronounced inverse kinetic isotope effects (IKIE) (kco,H/kco,D = 0.64–0.66) over the Fe and Co catalysts and a moderate IKIE (kco,H/kco,D = ∼0.8) on the Ru catalysts for the CO hydrogenation were obtained under typical FTS conditions. The IKIE was also found in CH4 formation, but the Co and Ru catalysts showed stronger IKIE than the Fe catalysts (kCH4/kCD4 = 0.6 vs 0.87). Regardless of catalyst type, only a minor normal KIE for the CO2 formation was obtained (kCO2, H/kCO2, D ˜ 1.1). The IKIE was found on various light 1-olefins and n-paraffin hydrocarbons as well. All the IKIEs can be explained by thermodynamic and kinetic isotope effects. The results suggested that deuterium was involved in quasi-equilibrated and hydrogenation steps that determined KIE. However, the Fe, Co and Ru catalysts showed different deuterium isotopic effect for the hydrocarbon selectivity. Deuterium promoted chain growth, thus lowered CH4 and light hydrocarbons selectivities and enhanced C5+ selectivity on both the Fe and Co catalysts; while it enhanced the hydrogenation rate to the low hydrocarbons and suppressed the formation of heavier hydrocarbons on the Ru catalysts. Deuterium isotopic effect on the formation of 1-olefins, n-paraffins and 2-olefins in C10-C18 range (in liquid phase) was also studied in detail. Deuterium was found to enhance 1-olefins formation, but suppressed or only slightly changed n-paraffins formation over the Fe and Co catalysts. However, deuterium led to greater amount of n-paraffins and less 1-olefins on the Ru catalysts. The results suggested that the IKIE originated from different hybridization changes of carbon in C–H (sp1->sp2 and/or sp2->sp3) on the Fe, Co and Ru catalysts, which implied different reaction pathways on the Fe, Co and Ru catalysts.

The decarboxylation pathway in ethanol steam reforming ultimately favors higher selectivity to hydrogen over the decarbonylation mechanism. The addition of an optimized amount of Cs to Pt/m-ZrO2 catalysts increases the basicity and promotes the decarboxylation route, converting ethanol to mainly H2, CO2, and CH4 at low temperature with virtually no decarbonylation being detected. This offers the potential to feed the product stream into a conventional methane steam reformer for the production of hydrogen with higher selectivity. DRIFTS and the temperature-programmed reaction of ethanol steam reforming, as well as fixed bed catalyst testing, revealed that the addition of just 2.9% Cs was able to stave off decarbonylation almost completely by attenuating the metallic function. This occurs with a decrease in ethanol conversion of just 16% relative to the undoped catalyst. In comparison with our previous work with Na, this amount is—on an equivalent atomic basis—just 28% of the amount of Na that is required to achieve the same effect. Thus, Cs is a much more efficient promoter than Na in facilitating decarboxylation.

The effect of the direct reduction of cobalt nitrate versus the more conventional calcination/reduction treatment has been investigated. Porosity properties of the catalysts are not significantly modified by avoiding the calcination step, as similar BET surface area, pore volume and pore diameter are obtained for the activated catalysts. In contrast, the cobalt reducibility decreases, but smaller cobalt particles size and higher dispersion are obtained. The reduction phenomena occurring for the uncalcined catalysts are more complex because of the additional nitrate decomposition steps. TPR-MS and TPR-XANES point out that CoOx intermediate species are formed during the reductive nitrate decomposition. However, these species are oxidized by NOX (formed by nitrate decomposition) to spinel type Co3O4, which is then converted to CoO prior to the final reduction step to Co0. The addition of promoters (Pt, Re, Ru, Ag) improves the cobalt reducibility, especially by shifting the final reduction step (i.e., CoO to Co0) to lower temperature. FT activity testing data show that activated uncalcined catalysts have higher CO conversion following the initial decline and leveling off period relative to the activated calcined catalyst. The best performance is achieved with uncalcined Pt-12%Co/TiO2. This catalyst has the highest CO steady state conversion, which is 1.2 times higher than the Pt-promoted calcined catalyst. Moreover, its deactivation rate is 0.13%/h compared to 0.2%/h for the corresponding calcined catalyst. The difference in the catalytic activity is even higher for the un-promoted samples, where the activated uncalcined catalyst has almost double the CO conversion as compared to its calcined counterpart. Finally, the addition of other promoters such as Ru, Re and Ag has no significant effect on catalytic activity.

The decomposition selectivity of formaldehyde during steam reforming was explored using unpromoted and sodium promoted Pt/m-ZrO2 catalysts, and the Na content was varied (0.5%Na, 1%Na, 1.8%Na, 2.5%Na, and 5%Na). In situ DRIFTS experiments during temperature programmed reaction in flowing H2O revealed that formaldehyde is adsorbed at reduced defect sites on zirconia, where it is converted to formate species through the addition of labile bridging OH species. Formate species achieve a maximum intensity in the range of 125–175 °C, where only slight changes in intensity are observed. Above this temperature, the formate decomposition reactivity strongly depends on the Na loading, with the optimum loadings being 1.8%Na and 2.5%Na. CO2 temperature programmed desorption results, as well as a greater splitting observed between the formate νasym(OCO) and νsym(OCO) bands in infrared spectroscopy, indicate greater basicity is induced by the presence of Na. This strengthens the interaction between the formate -CO2 functional group and the catalyst surface, weakening the formate C-H bond. A shift in the ν(CH) band of formate to lower wavenumbers was observed by addition of Na, especially at 1.8%Na and higher loadings. This results in enhanced decarboxylation and dehydrogenation of formate, as observed in in situ DRIFTS, temperature-programmed reaction/mass spectrometry experiments of the steam reforming of formaldehyde, and fixed bed reaction tests. For example, 2.5%Na addition of 2.5% increased the CO2 selectivity from 83.5% to 99.5% and the catalysts achieved higher stable conversion at lower temperature than NiO catalysts reported in the open literature. At 5%Na loading, Pt sites were severely blocked, hindering H-transfer.

This report will compile the outcomes of the work performed in Task 2.1 (Political and societal drivers and requirements), informing on the potential of evolving trends in technological progress in advancing contemporary marine environmental monitoring practices and examining the role any resulting changes in established operating paradigms could play in shaping the socio-political framework defining ocean observing needs at the global and European levels

A Before–Intermediate–After Multiple Sites (BIAMS) analysis, namely a modified version of the Before–After–Control–Impact (BACI) approach, was used to evaluate the possible effects of fishery management measures implemented in the Pomo/Jabuka Pits area, a historically highly exploited ground for Italian and Croatian fisheries, whose impact may have contributed over the years to the modification of the ecosystem. Since 2015, the area was subject to fishing regulations changing the type of restrictions over time and space, until the definitive establishment in 2018 of a Fishery Restricted Area. These changes in the regulatory regime result in complex signals to be interpreted. The analysis was carried out on abundance indices (i.e., kg/km2 and N/km2) of five commercially or ecologically relevant species, obtained in the period 2012–2019 from two annual trawl surveys. BIAMS was based on the selection of a Closure factor, declined in three levels (i.e., BEFORE/INTERMEDIATE/AFTER) and accounting for regulation changes in time, and on three adjacent strata (i.e., “A”, “B”, and “ext ITA”) a posteriori determined according to the latest regulations. BIAMS allowed us to identify early effects (i.e., changes in abundances), overcoming the unavailability of a proper independent control site; furthermore, the selection of adjacent strata allowed the inference of possible interactions among them.

Recent studies have shown that appropriate levels of alkali promotion can significantly improve the rate of low-temperature water gas shift (LT-WGS) on a range of catalysts. At sufficient loadings, the alkali metal can weaken the formate C–H bond and promote formate dehydrogenation, which is the proposed rate determining step in the formate associative mechanism. In a continuation of these studies, the effect of Rb promotion on Pt/ZrO2 is examined herein. Pt/ZrO2 catalysts were prepared with several different Rb loadings and characterized using temperature programmed reduction mass spectrometry (TPR-MS), temperature programmed desorption (TPD), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), an x-ray absorption near edge spectroscopy (XANES) difference procedure, extended x-ray absorption fine structure spectroscopy (EXAFS) fitting, TPR-EXAFS/XANES, and reactor testing. At loadings of 2.79% Rb or higher, a significant shift was seen in the formate ν(CH) band. The results showed that a Rb loading of 4.65%, significantly improves the rate of formate decomposition in the presence of steam via weakening the formate C–H bond. However, excessive rubidium loading led to the increase in stability of a second intermediate, carbonate and inhibited hydrogen transfer reactions on Pt through surface blocking and accelerated agglomeration during catalyst activation. Optimal catalytic performance was achieved with loadings in the range of 0.55–0.93% Rb, where the catalyst maintained high activity and exhibited higher stability in comparison with the unpromoted catalyst.

This study reports the shapes, dimensional classes, types and counts of microplastics (MPs) found in 23 individuals of N. norvegicus collected from two wild populations of the Adriatic Sea (Mediterranean basin). The focus was on three different anatomical compartments (gut, hepatopancreas and tail), which were analysed separately. MPs were found in all the investigated individuals with an average of about 17 MPs/individual. Fragments were predominant over fibers with a ratio of about 3:1. The majority of MPs were in the dimensional range 50–100 μm. The predominant polymers were polyester, polyamide 6, polyvinyl chloride and polyethylene, which together constitute about 61% of all the MPs found. Fragments were more concentrated in the hepatopancreas, with no significant difference between gut and tail, while fibers were more concentrated in the gut than in the tail with hepatopancreas somehow in between. The dimensional class of the MPs influences their anatomical distribution. There were no statistical differences among individuals from the two sampling sites. Sex of the individual did not influence the level of retained MPs, while length had a very marginal effect. The information reported here contributes to understanding of the possible risks linked to human consumption of different tissues from contaminated Norway lobsters.

The effect of cobalt substitution with nickel was investigated for the Fischer&ndash, Tropsch synthesis reaction. Catalysts having different Ni/Co ratios were prepared by aqueous incipient wetness co-impregnation, characterized, and tested using a continuously stirred tank reactor (CSTR) for more than 200 h. The addition of nickel did not significantly modify the morphological properties measured. XRD, STEM, and TPR-XANES results showed intimate contact between nickel and cobalt, strongly suggesting the formation of a Co-Ni solid oxide solution in each case. Moreover, TPR-XANES indicated that nickel addition improves the cobalt reducibility. This may be due to H2 dissociation and spillover, but is more likely the results of a chemical effect of intimate contact between Co and Ni resulting in Co-Ni alloying after activation. FTS testing revealed a lower initial activity when nickel was added. However, CO conversion continuously increased with time on-stream until a steady-state value (34%&ndash, 37% depending on Ni/Co ratio) was achieved, which was very close to the value observed for undoped Co/Al2O3. This trend suggests nickel can stabilize cobalt nanoparticles even at a lower weight percentage of Co. Currently, the cobalt price is 2.13 times the price of nickel. Thus, comparing the activity/price, the catalyst with a Ni/Co ratio of 25/75 has better performance than the unpromoted catalyst. Finally, nickel-promoted catalysts exhibited slightly higher initial selectivity for light hydrocarbons, but this difference typically diminished with time on-stream, once leveling off in conversion was achieved, the C5+ selectivities were similar (&asymp, 80%) for Ni/Co ratios up to 10/90, and only slightly lower (&asymp, 77%) at Ni/Co of 25/75.

Undoped and gallium-doped iron oxide catalysts (100Fe, 100Fe:2Ga, and 100Fe:5Ga) were prepared by following a continuous co-precipitation technique using ammonium hydroxide as precipitant. The catalysts were characterized by BET surface area, X-ray diffraction, H2-temperature programmed reduction, 57Fe Mossbauer spectroscopy, and temperature programmed decarburization techniques. The addition of gallium affects both reduction as well as carburization of iron oxide. The CO conversion decreases with an increase of gallium content relative to iron. The gallium-doped iron catalyst (100Fe:2Ga) exhibits initially a lower CO conversion after H2 activation than an undoped iron catalyst; however, the activity of the doped catalyst kept increasing with time. A strong interaction between iron oxide and gallium could explain the suppressed formation of χ-Fe5C2 and metallic iron during the carburization and reduction of iron oxide, respectively. The relative percentage of iron in χ-Fe5C2 was found to correlate with the initial rates of FT and WGS activity indicating that iron carbide is the main active component for both FT and WGS reactions.

The purpose of this investigation was to examine the effect of sulfur impurity on 1%Pt/KL-zeolite catalyst by co-feeding 500 ppbv hydrogen sulfide (H2S) during hexane aromatization under industrially relevant conditions using a plug flow reactor. Product selectivity and hexane conversion were measured with time-on-stream and compared to a clean run carried out under otherwise identical conditions. Sulfur addition to the feed accelerated the rate of deactivation as observed by rapid declines in both hexane conversion and benzene selectivity; hexene selectivity, the product of the less structurally sensitive dehydrogenation reaction, increased significantly. After 20 h, which was enough time to observe sufficient deactivation, the reaction was stopped. For the purpose of catalyst characterization, after cooling to 150 °C, the catalyst was preserved in Polywax 725 to prevent catalyst oxidation. XANES analysis at the potassium K-edge suggests that the local environment for potassium was not significantly altered by sulfur addition, while sulfur K-edge results indicate that sulfur bound to platinum to form platinum sulfide (PtS, not PtS2). Platinum sulfide is likely responsible for accelerating Pt growth, as observed in DRIFTS of adsorbed CO and HR-TEM/STEM micrographs.

Ga- and In-modified ceria (Ce 0.8 Ga 0.2 O 2 , Ce 0.8 In 0.2 O 2 ) materials were used as supports for cobalt-catalyzed Fischer-Tropsch synthesis (FTS). The addition of Ga to ceria was found to improve CO conversion for cobalt-catalyzed FTS, while the addition of In tended to decrease it. A similar trend was observed with the Ag-promoted cobalt/ceria catalysts. Doping of ceria with Ga or In decreased methane and increased the selectivity to olefins and alcohols for Ag-promoted cobalt/ceria. The sum of the products of olefins and alcohols for various catalysts exhibited a decreasing trend as follows: Ag-Co/Ce-Ga > Ag-Co/Ce-In > Ag-Co/Ce. Results of H 2 -TPR-XANES showed that adding of Ga or In to ceria increases the fraction of Ce 3+ in the surface shell for both unpromoted and Ag-promoted catalysts in the range of temperature typical of catalyst activation. This partially reduced ceria plays an important role in controlling the product selectivity of cobalt-catalyzed FT synthesis.

In previous work, Na-doping of Pt/YSZ was found to facilitate the low temperature water gas shift reaction (LT-WGS), and the promoting effect was ascribed to an electronic weakening of the C H bond of the formate species, a proposed intermediate in the catalytic cycle. Formate has also been implicated as an intermediate in steam-assisted formic acid decomposition (SAFAD) and methanol steam reforming (MSR) pathways. In the current contribution, Na-doping was also found to significantly accelerate the SAFAD reaction. The high activity of Pt/YSZ for SAFAD, as well as the promoting effect of Na, are in stark contrast to the view that formates are too stable, precluding them as intermediates for LT-WGS. With MSR, a remarkable promoting effect of Na doping was observed in the selectivity to CO 2 (>90% for Na-doped relative to 22% for undoped at 300 °C); however, at the doping levels used in the current work, the activity was lower for the Na doped catalyst and further optimization is needed to improve MSR conversion.

The promoting effect of Mn and Zn on the performance of Fe-based catalysts has been comparatively investigated in the COx hydrogenation to heavy hydrocarbons in the presence of H2-deficient streams. To this scope, two catalysts have been prepared by coprecipitation, followed by impregnation with Cu and K, and tested at 220 °C and 30 barg after an activation treatment with syngas. Both catalysts have been found to be active and selective to long-chain hydrocarbons in the presence of either H2/CO or H2/CO2 mixtures. Despite lower catalyst reducibility, the presence of Zn has resulted in higher COx conversion rates. Furthermore, the Zn-promoted catalyst converted COx into heavier and less-saturated hydrocarbons. These results are consistent with a role of Zn in promoting the catalyst basicity, which is a key property to keep low the superficial H/C ratio and to slow chain termination reactions as well as secondary olefin hydrogenations. © 2017 American Chemical Society.

XANES K-edge spectra of potassium promoter in precipitated Fe catalysts were acquired following activation by carburization in CO and as a function of time on-stream during the course of a Fischer–Tropsch synthesis run for a 100Fe:2K catalyst by withdrawing catalysts, sealed in wax product, for analysis. CO-activated and end-of-run spectra of the catalyst were also obtained for a 100Fe:5K catalyst. Peaks representing electronic transitions and multiple scattering were observed and resembled reference spectra for potassium carbonate or potassium formate. The shift in the multiple scattering peak to higher energy was consistent with sintering of potassium promoter during the course of the reaction test. The catalyst, however, retained its carbidic state, as demonstrated by XANES and EXAFS spectra at the iron K-edge, suggesting that sintering of potassium did not adversely affect the carburization rate, which is important for preventing iron carbides from oxidizing. The method serves a starting point for developing better understanding of the chemical state and changes in structure occurring with alkali promoter.