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Removing carbon dioxide from industrial effluents (i.e. flue gas) via solid sorbents is a potential greenhouse gas mitigation strategy. Lithium orthosilicate (Li4SiO4) is one of the most promising materials for CO2 capture at high temperature (500-700 °C). In this study, the non-hydrolytic sol-gel technique was used to synthesized Li4SiO4 nanoparticles for improving lithium silicate features as solid sorbent for carbon dioxide. The CO2 sorption properties of the obtained nanoparticles were investigated by using a thermal gravimetric analyzer (TGA) in a controlled gas flow environment at CO2 partial pressure of 0.6 atm and at 700 °C. Li4SiO4 nanoparticles with average diameter less than 100 nm aggregated in clusters less than 500 nm were obtained. An amount of adsorbed carbon dioxide of 6.9 mmol of CO2/g sorbent, corresponding to an 82.4 % conversion of lithium orthosilicate, was reached. The promising results could be related to high surface area of nano-size material synthesized by sol- gel process.

Hydrothermal carbonization (HTC) is a thermo-chemical process for recovery and valorization of biomass and organic waste that uses sub-critical liquid water as a reaction medium for converting feedstock into value- added products.. HTC treatment produces a carbonaceous solid, named hydrochar, with attractive characteristics that can be used in a variety of applications, such as activated carbon or soil amendment. In this study, activated carbons were prepared by KOH chemical activation of hydrochars obtained from hydrothermal carbonization of green waste and municipal solid waste. The effects of precursors and different KOH/char mass ratios on physical characteristics of the activated carbon were investigated. Methylene blue and iodine numbers were determined to evaluate the adsorption properties of obtained activated carbons. The results have shown a significant increase of porosity and a change in hydrochar structure by KOH activation method. The amount of mesopores and micropores increase with increasing KOH/char ratio. In particular, the sample by treatment of hydrochar from green waste activated with a 2:1 KOH/char weight ratio presented good mesoporosity, with a methylene blue number of 385 mg/g, and a well-developed micropore structure, with iodine number of 747 mg/g. Therefore, the application of KOH activated hydrochar as activated carbon appears to be promising.

In recent years, small scale cogeneration systems (< 500 kWe) distributed in different geographical locations using biomass has received special attention as economically competitive and environmentally friendly ways of producing energy. These systems can be integrated to industrial and agricultural activities where biomass residues are generated and can be converted into electricity and thermal energy by combustion or gasification. The legislations of many European countries such as Italy concerning renewable energy and energy efficiency along the taxation schemes have raised the incentives for small scale cogeneration plants. Consequently, there is a clear economic interest of the companies in this sector and there is also a scientific interest towards demonstration of their energetic efficiency, environmental performance and reliability. Among the suggested technologies for the biomass conversion into energy, downdraft gasification (using air as gasification agent), coupled with internal combustion engines, has the advantage of high electric efficiency (~ 25%) and low tar generation, making easier the gas cleaning process necessary for its use into engines. In the present work, the results of a measurement campaign performed on a commercial scale 350 kWth downdraft woodchips gasification plant, coupled with an SI internal combustion engine (ICE), are presented and discussed. The main goals of this first experimental campaign have been to verify the stability of gasifier and engine operation, operability of the plant and to determine its energy efficiency. The campaign verified a stable operation of the gasifier and the plant produced a syngas with a composition suitable for a gas engine. The energy balance resulted in a potential overall wood fuel to electricity efficiency of about 23 %.

With the awareness of the need for optimal and sustainable use of natural resources, hydrothermal treatment of biomass and biomass waste for energy and resource recovery has received increasing attention. The hydrothermal carbonization (HTC) of a biomass is achieved using water as the reaction medium and applying mild temperatures (180–250 ° C) under saturated pressure (autogenous or provided by a gas) for several hours. The thermochemical process applied to biomass includes simultaneous reactions of hydrolysis, dehydration, decarboxylation, condensation, polymerization and aromatization of the original precursor. The main resulting products are a carbon-rich solid, known as hydrochar, and a water phase containing soluble organic compounds. In this work, an experimental study on HTC process of orange peels to assess the yield of levulinic acid in water phase during the acid-catalyzed hydrolysis is reported. The results are promising, and comparable with other lignocellulosic biomass sources.

Since the CO2 separation is the first and most energy intensive step of carbon capture and storage (CCS) technology, many research have targeted at improving the current technologies or developing new approaches of CO2 separation and capture. In this study, lithium orthosilicate-based pellets were developed and characterized as potential regenarable high-temperature CO2 sorbents. A mechanical method was used for pelletization of the powdered materials, namely K2CO3-doped lithium silicate (Li4SiO4). For increasing the performance of the pellets over multiple cycles an activation strategy was applied: the powdered sorbents were pelletized with a binder for enhancing their porosity by applying a thermal activation before adsorption process. Different amounts of binders (layered graphite and carbon nanotubes) were added to powered doped-sorbent in order to identify the optimal amount to ensure an adequate porosity into the pellets. The CO2 sorption properties of the obtained pellets were investigated by using a thermal gravimetric analyzer (TGA) in a controlled gas flow environment at low CO2 partial pressure (0.04 atm). Compared to the pure K2CO3-doped lithium silicate pellets, the sorbents prepared using layered graphite showed greater CO2 capture capabilities, which were ascribed to the higher porosity developed as a result of the activation. At 580 °C and a CO2 partial pressure of 0.04 atm, the uptake of CO2 in pellets prepared with 20 % of graphite reached about 200 mg CO2/g sorbent within 120 minutes corresponding to a Li4SiO4-conversion of 72.1 %. During multiple sorption/desorption cycles, a decay of the sorption capacity of the pellets was observed due to a partial sintering of the materials.

Polyhydroxyalkanoates (PHAs) are a family of biopolyesters produced by many bacteria as intracellular storage carbon and energy source. Poly-ß-hydroxybutyrate (PHB) is probably the most common type of PHA. It is biodegradable and renewable, with relevant thermoplastic properties along with adjustable thermal and mechanical properties. The thermoplastic properties of PHB and its biodegradability make it a potential alternative to petroleum-based plastics. Several microorganisms growing in the dark and/or in the light produce PHB. The polymer is mainly accumulated in the cytoplasm of cells when microorganisms are growing under conditions of stress. If purple non-sulfur photosynthetic bacteria (PNSB) are grown under nitrogen starvation conditions, a photoevolution of molecular hydrogen occurs as well. The PHB amount increases when carbon and energy sources are in excess, but the growth is limited, for example, by the lack of a nitrogen, phosphorous or sulfur source. This work deals the possibility of producing PHAs by photosynthetic microorganisms belonging to cyanobacteria and PNSB. Different culture broths, with and without organic carbon sources, were investigated to maximize PHA production by photosynthetic microorganisms. An unbalanced agro-industrial wastewater has been also investigated in the present study. It concerns the olive mill wastewater (OMW) containing significant reusable carbon fractions suitable for an eco-efficient valorization by feeding photosynthetic processes. The maximum PHA concentration in a cyanobacterium dry- biomass was 317 mg/L, when growing cells in a medium with a low content of acetic acid (LAC). In PNSB dry- biomass the maximum PHB content was 215 mg/L, when growing PNSB in a synthetic medium. A simultaneous H2 co-production (1,295 mL/L of culture) was cumulated as well, at the end of the process.

In this work, blends of poly(3-hydroxybutyrate) (PHB), the most widespread member of the polyhydroxyalkanoates (PHAs), with wood fibres were investigated to assess the feasibility of producing biodegradable materials suitable for applications in packaging and agricultural environment. Due to its high crystallinity, PHB is stiff and brittle resulting in very poor mechanical properties with low extension at break, which limits its range of application. PHB was compounded successfully with wood fibres up to 30 % by weight in presence of polyethylene glycol (PEG) by extrusion. The composites were characterized by differential scanning calorimetry (DSC) and by scanning electron microscopy (SEM). Their mechanical properties were tested by dynamic mechanical thermal analysis (DMTA) and tensile tests. Preliminary tests in soil were carried out on the samples with wood fibres in order to investigate their biodegradation behavior, and further tests were performed in compost. Polyethylene glycol resulted effective as lubricating agent for the production of composites based on PHB and fibres. The good preliminary biodegradability results in soil showed that the blends PHB/wood fibres appear suitable for the production of natural fibre-reinforced thermoplastic items degradable in agricultural environment.

In this study, high-temperature CO2 capture by solid sorbent based on lithium orthosilicate (Li4SiO4) was investigated in the presence of gas contaminants, such as NO and SO2. Simulated flue gas containingCO2 (4 vol%), SO2 (up to 2,000 ppm), and NO (up to 1,000 ppm) was used during the CO2 capture process. The CO2 sorption properties of the sorbent were investigated at high temperature (580 °C) by a thermal gravimetric analyzer (TGA). The tested sorbent showed high CO2 sorption capacity (210 mg CO2/g sorbent) along with high absorption rates, and lower regeneration temperature than other solids such as calcium oxide. The results also showed that the solid sorbent is inert with respect to NO. Instead, the presence of SO2 resulted in a negatively effect on the sorption capacity of the sorbent, due to an irreversible reaction with the adsorbent. Thus, industrial application would require desulfurization of flue gas prior to contacting the sorbent.

The use of plastics packaging is widespread. For this reason, there is a growing interest in develop of novel materials by blends of synthetic and natural polymers which can help to reduce the environmental impact of plastics. Hydrolyzed collagen (HC) from leather industry is an inexpensive natural biopolymer and it is a promising material for blending with synthetic polymers (e.g., polyethylene) to produce different types of item (it is no food competition, low cost, and biodegradable-compostable). Due to the wide di?erence in polarity, the natural polymer does not disperse easily in nonpolar thermoplastics, therefore the structural di?erencesbetween polyethylene and collagen hydrolizate make them incompatible. Thus, in this work compatibilizingagents as maleic anhydride functionalized ethylene elastomers have been used. The content of HC in polyethylene matrix varied between 10 and 50 wt%. Transparent, cohesive and flexible films, having an average thickness of 60 µm, were obtained by using the film blowing technique. Film blowing is a shaping technique used extensively to produce most plastics films and bags for packaging applications. The extruded films were characterized through mechanical testing, scanning electron microscopy, and thermal analysis. The films containing up to 20 % of collagen hydrolizate, in the presence of compatibilizing agents, are characterized by satisfactory thermal-mechanical properties. Thus HC/PE blends appear as promising candidate for the production of innovative material suitable for production of thermoplastic items for applications in packaging and agricultural segments.

Actually, several applications of small (=1 MWe) CHP (Combined Heat and Power) plants fuelled with solid wood can be found in Europe. Innovative technologies are facing the market, giving new perspectives for wood utilisation in district heating and/or in industrial-commercial activities. However, while the energy saving and the environmental benefits of CHP plants are undoubted, technological and no technological barriers still obstacle their large diffusion. The present study reports a comparative evaluation of the different available technologies in terms of thermal and electric efficiencies and their possible applications. Taking into consideration the electric-thermal performances of each configuration and the actual economic incentives guaranteed by the Italian government, a preliminary estimation of economic convenience of each plant is given.

As an alternative to the traditional process based on the use of sulfides, an unhairing process in drum by hydrogen peroxide, named DEPOXO, was developed for the production of high-quality bovine upper leather. A preliminary investigation at laboratory scale has allowed to set out the optimal process conditions, in terms of H2O2 dosage (9 %) and pH (12.5), in order to achieve an effective unhairing and a compatible swelling of hides. The following pilot-scaled runs have assessed the industrial feasibility of the process that allows the production of a versatile base for different final applications of the leather (either chrome or vegetable tanned), and appear practical to implement. The crust leather obtained by the oxidative unhairing process showed good physical-mechanical and technical properties comparable with those obtained by the traditional one, and the leather was technically assessed as satisfactory and suitable according to the market request. The actual reduction of the environmental impact of the novel process, in relation with the traditional one, was evaluated performing a Life Cycle Assesment (LCA) using SimaPro 7.3, one of the most used software for LCA analysis. The results of the life cycle impact assessment underline that damages on main impact categories are greatly reduced through the adoption or the oxidative unhairing. Therefore, the DEPOXO process appears a feasible process, either from the environmental or from the technical point of view, to produce high quality bovine upper leather.

The Life Cycle Assessment (LCA) is an ISO standardized and widely used methodology for environmental assessment of products, processes and services, by identifying, quantifying and evaluating all the resources consumed and all the emissions and wastes released. The LCA methodology enables adequate comparison between different remediation options and can be used as a decision-making tool for the authorities. In this study, LCA was used to compare, in terms of their associated environmental burdens, two scenarios for managing the contaminated dredged sediments of the seabed of the Livorno Port area. The compared options were: (i) confined longshore disposal, i.e. placement of dredged material in a confined disposal facility; (ii) phytoremediation treatment, by an association of salt-tolerant shrub and grass species, aimed at turning the polluted sediment an agronomic substrate (techno-soil). The results of the life cycle impact assessment underline that the potential impacts of the two compared options involve different environmental problems. Indeed, for phytoremediation the most significant impacts are related to energy and resources consumption, while for the confined disposal is related to loads in the marine ecotoxicity categories. Therefore, phytoremediation can be considered a promising alternative solution for the management and valorization of contaminated dredged sediments.

In this study, lithium orthosilicate-based pellets were developed and characterized as potential regenarable high-temperature CO2 sorbents. A mechanical method was used for pelletization of the powdered materials, namely K2CO3-doped lithium silicate (Li4SiO4) with cellulose fibres. Different amounts of cellulose fibres (20, 30 and 40 wt%) were added to powered doped-sorbent in order to identify the optimal amount to ensure an adequate porosity to the produced pellets. The CO2 sorption properties of the produced pellets were investigated at high temperature (500 - 600 °C) by using a thermal gravimetric analyzer (TGA) at low CO2 partial pressure with repeated calcination/carbonation cycles. Compared to the pure K2CO3-doped lithium silicate pellets, the sorbents prepared using cellulose fibres showed greater CO2 capture capabilities, which were ascribed to the higher porosity developed as a result of thermal degradation of cellulose. At 580 °C and a CO2 partial pressure of 0.04 atm, the uptake of CO2 in pellets prepared with 20 % of cellulose fibres reached about 20 wt% within 120 min corresponding to a Li4SiO4-conversion of 57 %. During multiple sorption/desorption cycles, a decay of the sorption capacity of the pellets was observed due to a partial sintering of the materials. This suggested that an appropriate binder should be added in order to improve the cyclic stability and the strength of the produced pellets.

In this paper, a one-dimensional unsteady state mathematical model for the simulation of a small scale fixed-bed updraft gasifier is presented. The model is based on a set of differential equations which couples heat and mass transport in the solid and gas phases with sewage sludge drying and devolatilization, char gasification and combustion of both char and gaseous species. The model was used to simulate the behavior of sewage sludge with 20 % moisture in an updraft fixed-bed gasifier (2 m height, 0.165 m i.d.) of a pilot-scale plant operating at atmospheric pressure. Good agreement was achieved between predictions and experimental measurements for the dynamic axial temperature profiles and the steady state composition of the producer gas.

Solid sorbents based on lithium orthosilicate (Li4SiO4) have shown promise for CO2 capture at high temperature. Improved sorption properties can be obtained by appropriate doping. In this study, different promoted Li4SiO4-based sorbents were prepared by addition of potassium carbonate and binary/ternary alkali (Li, K and Na) carbonate eutectic mixtures. The CO2 sorption properties of the sorbents were investigated by thermal gravimetric analysis (TGA) at different temperatures in the range between 500 and 600 °C and at low CO2 partial pressure (0.04 atm). The results showed that all the promoters used noticeably improved the CO2 sorption capacity in comparison to no-promoted Li4SiO4. At the optimum sorption temperature of 580 °C, Li4SiO4 with addition of 30 wt% of K2CO3 showed the best CO2 adsorption proprieties with sorption capacities of 230 mg CO2/g sorbent corresponding to a conversion of about 80 %. Besides this sample maintained its original capacity during multiple CO2 sorption/desorption cycles.

Microglia chronic activation is a hallmark of several neurodegenerative diseases, including the retinal ones, possibly contributing to their etiopathogenesis. However, some microglia sub-populations have anti-inflammatory and neuroprotective functions, thus making arduous deciphering the role of these cells in neurodegeneration. Since it has been proposed that functionally different microglia subsets also rely on different metabolic routes, we hypothesized that modulating microglia metabolism might be a tool to enhance their anti-inflammatory features. This would have a preventive and therapeutic potential in counteracting neurodegenerative diseases. For this purpose, we tested various molecules known to act on cell metabolism, and we revealed the anti-inflammatory effect of the FDA-approved piperazine derivative Ranolazine on microglia cells, while confirming the one of the flavonoids Quercetin and Naringenin, both in vitro and in vivo. We also demonstrated the synergistic anti-inflammatory effect of Quercetin and Idebenone, and the ability of Ranolazine, Quercetin and Naringenin to counteract the neurotoxic effect of LPS-activated microglia on 661W neuronal cells. Overall, these data suggest that using the selected molecules -also in combination therapies- might represent a valuable approach to reduce inflammation and neurodegeneration while avoiding long term side effects of corticosteroids., (© 2023. The Author(s).)

The management of sewage sludge is currently an open issue due to the large volume of waste to be treated and the necessity to avoid incineration or landfill disposal. Hydrothermal carbonization (HTC) has been recognized as a promising thermochemical technique to convert sewage sludge into value-added products. The hydrochar (HC) obtained can be suitable for environmental application as fuel, fertilizer, and sorbent. In this study, activated hydrochars (AHs) were prepared from sewage sludge through HTC followed by chemical activation with potassium hydroxide (KOH) and tested for the removal of pollutants in gaseous and aqueous environments, investigating carbon dioxide (CO 2 ) and ciprofloxacin (CIP) adsorption capacity. The effects of activation temperature (550-750 °C) and KOH/HC impregnation ratio (1-3) on the produced AHs morphology and adsorption capacity were studied by Response Surface Methodology (RSM). The results of RSM analysis evidenced a maximum CO 2 uptake of 71.47 mg/g for mild activation conditions (600-650 °C and KOH/HC = 1 ÷ 2), whereas the best CIP uptake of 628.61 mg/g was reached for the most severe conditions (750 °C, KOH/HC = 3). The prepared AHs were also applied for the removal of methylene blue (MB) from aqueous solutions, and the MB uptake results were used for estimating the specific surface area of AHs. High surface areas up to 1902.49 m 2 /g were obtained for the highest activation temperature and impregnation ratio investigated. Predictive models of CO 2 and CIP uptake were developed by RSM analysis, and the optimum activation conditions for maximizing the adsorption performance together with high AH yield were identified: 586 °C and KOH/HC ratio = 1.34 for maximum yield (26.33 %) and CO 2 uptake (67.31 mg/g); 715 °C and KOH/HC ratio = 1.78 for maximum yield (18.75 %) and CIP uptake (370.77 mg/g). The obtained results evidenced that chemical activation of previously HTC-treated sewage sludge is a promising way to convert waste into valuable low-cost adsorbents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Today application of sewage sludge (SL) and hydrochar (HC) in agriculture is a common practice for soil conditioning and crop fertilization, however safety concerns for human and environmental health due to the presence of toxic compounds have recently been expressed. Our aim was to test the suitability of proteomics coupled with bioanalytical tools for unravelling mixture effects of these applications in human and environmental safety assessment. We conducted proteomic and bioinformatic analysis of cell cultures used in the DR-CALUX® bioassay to identify proteins differentially abundant after exposure to SL and the corresponding HC, rather than only using the Bioanalytical Toxicity Equivalents (BEQs) obtained by DR-CALUX®. DR-CALUX® cells exposed to SL or HC showed a differential pattern of protein abundance depending on the type of SL and HC extract. The modified proteins are involved in antioxidant pathways, unfolded protein response and DNA damage that have close correlations with the effects of dioxin on biological systems and with onset of cancer and neurological disorders. Other cell response evidence suggested enrichment of heavy metals in the extracts. The present combined approach represents an advance in the application of bioanalytical tools for safety assessment of complex mixtures such as SL and HC. It proved successful in screening proteins, the abundance of which is determined by SL and HC and by the biological activity of legacy toxic compounds, including organohalogens., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ilaria Corsi reports financial support was provided by Tuscany Region., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Levulinic acid production by acid-catalyzed hydrothermal conversion of (ligno)cellulosic biomass generates significant amounts of carbonaceous hydrochar, which is currently considered a final waste. In this work, the hydrochar recovered after the levulinic acid production, was subjected to cascade pyrolysis and chemical activation treatments (by H 3 PO 4 or KOH), to synthesize activated carbons. The pyrolysis post-treatment was already effective in improving the surface properties of the raw hydrochar (Specific Surface Area: 388 m 2 /g, V P : 0.22 cm 3 /g, V MESO : 0.07 cm 3 /g, V MICRO : 0.14 cm 3 /g), by removing volatile compounds. KOH activation resulted as the most appropriate for further improving the surface properties of the pyrolyzed hydrochar, showing the best surface properties (Specific Surface Area: 1421 m 2 /g, V P : 0.63 cm 3 /g, V MESO : 0.10 cm 3 /g, V MICRO : 0.52 cm 3 /g), which synergistically makes it a promising system towards adsorption of CO 2 (∼90 mg/g) and methylene blue (∼248 mg/g). In addition, promising surface properties can be achieved after direct chemical activation of the raw hazelnut shells, preferably by H 3 PO 4 (Specific Surface Area: 1918 m 2 /g, V P : 1.34 cm 3 /g, V MESO : 0.82 cm 3 /g, V MICRO : 0.50 cm 3 /g), but this choice is not the smartest, as it does not allow the valorization of the cellulose fraction to levulinic acid. Our approach paves the way for possible uses of these hydrochars originating from the levulinic acid chain for new environmental applications, thus smartly closing the biorefinery loop of the hazelnut shells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Hydrothermal carbonization (HTC) is emerging as a promising technology for the management of sewage sludge. The fate of phytosanitary products, Polycyclic aromatic hydrocarbons (PAHs) and PCBs (Polychlorinated biphenyls) after HTC, as well as the formation of dioxins and furans, is still unclear. Moreover, only little information is available on the distribution of heavy metals and major nutrients between the hydrochars and the process water. Here, we aim to contribute to fill these gaps. HTC of sewage sludge from six different wastewater treatment plants has been carried out at 220 °C for 85 min. Feedstock, hydrochars and spent liquor have been then characterized and discussed. HTC is here proven to be a suitable technology for the immobilization of both heavy hydrocarbons and heavy metals, with the exception arsenic, which was also found in the spent liquor at a significant proportion (∼15-∼50%). DDD, DDT, DDE were detected in all sludge samples and their content was reduced by nearly one order of magnitude after the process. HTC is here proven to not be responsible at an appreciable extent of PCBs enrichment of the processed solids. Moreover, the sum of PCDDs and PCDFs in hydrochars never exceeded 20 ng kg -1 s.s. The results obtained encourage further developing of HTC, with the aim to improve the sustainability of sewage sludge management. Additional studies on the environmental impact of hydrochar when used as alternative fuel, as well as soil amendment, could lead to the overcoming of the issues which still hinder these applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Hydrothermal carbonization is considered a powerful technology to convert sewage sludge (SS) into a valuable carbonaceous solid known as hydrochar (HC). Up to now criteria for landfill application of SS and HC are based only on physicochemical properties and levels of pollutant residues. Nevertheless, to ensure their safe environmental applications it is mandatory to develop biosensors which can provide relevant information on their toxic potential for natural ecosystems. Therefore, this study aimed to assess the suitability of a contact assay using zebrafish embryo/larvae combined with sub-lethal end-points to evaluate the hazard associated with SS and related HC exposure. A suite of biomarkers was also applied on larvae, related to detoxification and oxidative stress as the activity of Ethoxyresorufin-O-deethylase, glutathione-S-transferase, and catalase, the content of reactive oxygen species and the behavioral assay using the DanioVision™ chamber. Legacy priority pollutants were also measured either in SS and HC tested samples and in contact waters. The exposure to SS caused higher lethality compared to HC. No significant changes in the activity of oxidative stress markers was observed upon exposure to both matrices. The behavioral test showed a hypoactivity condition in larvae exposed to both SS and HC with the effects of SS stronger than HC. Chemical analysis revealed the presence of trace elements and halogenated compounds in either SS, HC. Heavy metals were also released in contact waters, while volatile hydrocarbons (C6-C10) and halogenated compounds resulted below LOD (<0.05 μ L -1 ). Our study highlights the suitability of zebrafish embryotoxicity test, coupled with behavioral traits, as screening tool for assessing potential risks, associated with the landfill application of both SS and HC, for aquatic wildlife., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The objectives of this study are (1) to identify beneficiary-level characteristics associated with skilled nursing facility (SNF) length of stay (LOS), and (2) to determine if significant differences in LOS exist for vulnerable populations at the individual level or among nursing homes that serve a disproportionate share of vulnerable populations. This study employed 2014-2015 Medicare Long-Term Care Minimum Data Set (MDS v3.0) assessment, fee-for-service claims and enrollment, and 2014 Nursing Home Compare data to examine SNF LOS in Medicare beneficiaries. We used a hierarchical linear model to identify which beneficiary-level characteristics are associated with SNF LOS, while controlling for facility-level characteristics. After controlling for beneficiary-and facility-level characteristics, we found dual eligibility, racial or ethnic minority, depression, and Alzheimer's disease to be associated with longer Medicare covered SNF stays. We found that facilities that served higher proportions of dually eligible individuals tended to have higher average LOS compared to other facilities.

The suitability of the AhR reporter gene bioassays to screen the presence of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in sewage sludge (SL) and related hydrochar (HC) was here investigated. Samples of SL obtained from six WWTPs were processed by hydrothermal carbonization to obtain the resultant HCs and both tested with DR-CALUX® bioassay. Levels of PCDD/Fs and dl-PCBs were also determined analytically in the same samples by GC-MS/MS. Bioanalytical Toxicity Equivalent values (BEQ) resulted in one order of magnitude higher in HC compared to SL samples and those obtained from the dl-PCBs fraction higher than those from PCDD/Fs. BEQ and TEQ WHO values, the latter obtained by GC-MS/MS analysis on the same matrices, were highly correlated showing also a similar trend in the six WWTPs (R S = 0.8252, p < 0.001; Pearson's R R P =0.8029, p < 0.01). The suitability of AhR bioassays and in particular of the DR-CALUX® to screen the presence and biological activity of legacy organohalogen compounds in both SL and HC matrices was demonstrated for the first time which support their usage for the assessment of potential risks associated with their further environmental applications., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Hydrothermal carbonization can play an innovative role in sewage sludge (SS) treatment and valorization, as well as in phosphorus recovery. In this study, leaching tests using nitric acid were performed on hydrochar from SS and the influence of pH (1-3.5), leaching time (30-240 min), and solid/liquid (S/L) ratio (5-20 wt%) was analyzed and optimized according to the Design of Experiments method, under the Response Surface Methodology approach. The highest phosphorus extraction yield (59.57%) was achieved at the lowest pH and the lowest S/L ratio, while an increase in temperature from 20 to 60 °C negatively affected the phosphorus recovery. Quadratic models, with the addition of semi-cubic terms, were found to best represent both phosphorus yield and ash content of the hydrochar after leaching. As observed by 3-dimensional surface responses, phosphorus yield increases as the pH decreases. The pH is the factor that most influences this response, while time has little influence. At pH 1, the yield increases as the S/L ratio decreases, while the S/L ratio only slightly affects the response at pH 3.5. At an S/L ratio of 12.5%, multi-objective optimization indicates that pH 1 and a leaching time of 135 min are the parameters that allow both maximum phosphorus yield and minimum ash content.

Chlorpyrifos is an organophosphorus insecticide, acaricide and miticide used worldwide for the control of soil-borne insect pests. It must be considered as a substance of growing concern, given its use, toxicity, environmental occurrence, and potential for regional to long-range atmospheric transport. Considering the incomplete removal attained by conventional water treatment processes, we investigated the efficiency of electrolytic radicals production and sonoelectrolysis on the degradation of the pesticide. The treatment has been conducted in a novel electrochemical reactor, equipped with a boron-doped diamond anode and a solid polymer electrolyte (SPE). Different current intensity and times have been tested and coupled with sonication at 40 kHz. Up to 69% of chlorpyrifos was completely removed in 10 min by electrolysis operated at 0.1 mA, while 12.5% and 5.4% was converted into the treatment intermediates 3,5,6-trichloro-2-pyridinol (TCP) and diethyl (3,5,6-trichloropyridin-2-yl) phosphate, respectively. Ultrasound irradiation did not enhance the removal efficiency, likely due to mass transport limitations, while the energy consumption increased from 8.68∙10 - 6 to 9.34∙10 - 4 kWh µg - 1 removed. Further research is encouraged, given the promising processing by the SPE technology of low conductivity solutions, as pharmaceuticals streams, as well as the potential for water and in-situ groundwater remediation from different emerging pollutants as phytosanitary and personal care products., Competing Interests: Conflict of interestThe authors have no conflict of interest to declare., (© The Author(s) 2020.)

Introduction: Maintaining placement of the nasogastric feeding tube (NGT) is imperative in the double stage laryngotracheoplasty (dsLTP) patient because of concerns for adequate nutrition and hydration in the postoperative period. Additionally, multiple reinsertions due to displacement potentiate surgical morbidities. The purpose of this study was to compare NGT dislodgment rates in children with and without a commercial nasal bridle following a dsLTP surgical procedure and to determine if the use of a commercial nasal bridle decreases accidental tube dislodgements., Methods: Medical records of pediatric patients with NGT insertion for dsLTP between Jan 1, 2012 and June 15, 2018 were reviewed for nasal bridle use, demographics, feeding tube and bridle complications, x-rays to check NGT placement, length of stay (LOS), length of bridle use and accidental feeding tube dislodgements., Results: A total of 67 patients (34 unbridled and 33 bridled) received an NGT after dsLTP. No differences in demographics were noted, except the bridled group was older (median age 6.5 [IQR: 3.7, 14.3] than the unbridled group (median age 3.2 [IQR: 2.2, 6.8], p = 0.05). There were 24 episodes of NGT dislodgement in 16 patients in the unbridled group and zero displacements in the bridled patients resulting in an incidence of 9.4 [95%CI: 6.0, 14.0] and 0.0 [95%CI: 0.0, 1.9] pullouts per 100 days for unbridled versus bridled patients, respectively. Those with displacement had significantly more x-rays to check placement (p = 0.0004) and LOS was longer (p = 0.06) with a mean (SD) of 10.9 (7.0) vs. no displacement 7.0 (3.6) days. Of those bridled, 67% were discharged with a bridle and 86% returned with the NGT and bridle in place (mean bridle placement of *** ± days) at the time of stent removal. No feeding tube or bridle complications were reported for either group., Conclusion: The commercial nasal bridle significantly reduced NGT displacements without complication in the examined pediatric sample s/p dsLTP. Bridle use was associated with decreased radiology exposure and LOS and was successfully used in the outpatient setting., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Hydrothermal carbonization (HTC) of sewage sludge reduces the waste volume and can be source of energy and valuable products. Furthermore, HTC offers several advantages over conventional dry-thermal pre-treatments, as no prior drying is requested, and the high quality of the char produced promotes applications as energy production and storage, wastewater remediation, and soil amendment. Relationships between char yields, physicochemical properties and process parameters are here analysed, with the aim to provide insight into the choice of the process severity required to fit the desired application. Moreover, presence and fate of heavy metals and organic contaminants are discussed. The highest reaction temperature is the main parameter affecting the physicochemical characteristics of the char produced, while the heating rate governs the heat mass transfer and the rate of intermediates formation. Depolymerization of the biomass results in a reduction of the oxygen to carbon ratio and, therefore, in augmented high heating values, further increased by deposition of 5-(hydroxymethyl)furfural. Recirculation of process water may enhance dehydration reactions and the deposition of degraded polymers, increasing dewaterability and yield, but field trials are recommended to assess the feasibility of this option. An overuse of chars for energy generation purposes would be deleterious for the environmental life cycle. Further research is encouraged to assess the pollutants abatement and their degradation pathways when incorporated in the carbonaceous product, to promote the application of hydrochars as soil amendment, as well as for environmental remediation purposes., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

For the first time, the exploitation of hazelnut shells for the combined production of levulinic acid (LA) and hydrochar was investigated. The optimization of the catalytic hydrothermal treatment was performed both in autoclave and microwave reactor, approaching a maximum LA yield of ∼9-12wt%. Hydrochars recovered with high yield (∼43-47wt%) were characterized by different techniques, including elemental and proximate analysis, heating value, FT-IR, XPS, XRD, SEM-EDX, and SAA. Their "lignite-like" energetic properties make them suitable for the energy recovery within the same biorefinery plant for LA production, thus partially offsetting the cost of the entire process. Alternatively, since the synthesized hydrochars maintain high levels of oxygenated groups, they could be smartly exploited as natural sorbents for environmental applications. The proposed integrated approach makes possible to fully exploit this waste, smartly closing its biorefinery cycle in a sustainable development perspective., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Bio-composites based on polyhydroxyalkanoates (PHAs) and fibres of Posidonia oceanica (PO) were investigated to assess their processability by extrusion, mechanical properties, and potential biodegradability in a natural marine environment. PHAs were successfully compounded with PO fibres up to 20 wt % while, at 30 wt % of fibres, the addition of 10 wt % of polyethylene glycol (PEG 400) was necessary to improve their processability. Thermal, rheological, mechanical, and morphological characterizations of the developed composites were conducted and the degradation of composite films in a natural marine habitat was evaluated in a mesocosm by weight loss measure during an incubation period of six months. The addition of PO fibres led to an increase in stiffness of the composites with tensile modulus values about 80% higher for composites with 30 wt % fibre (2.3 GPa) compared to unfilled material (1.24 GPa). Furthermore, the impact energy markedly increased with the addition of the PO fibres, from 1.63 (unfilled material) to 3.8 kJ/m² for the composites with 30 wt % PO. The rate of degradation was markedly influenced by seawater temperature and significantly promoted by the presence of PO fibres leading to the total degradation of the film with 30 wt % PO in less than six months. The obtained results showed that the developed composites can be suitable to manufacture items usable in marine environments, for example, in natural engineering interventions, and represent an interesting valorisation of the PO fibrous wastes accumulated in large amounts on coastal beaches.

In the present work, the gasification with air of dehydrated sewage sludge (SS) with 20 wt.% moisture mixed with conventional woody biomass was investigated using a pilot fixed-bed updraft gasifier. Attention was focused on the effect of the SS content on the gasification performance and on the environmental impact of the process. The results showed that it is possible to co-gasify SS with wood pellets (WPs) in updraft fixed-bed gasification installations. However, at high content of sewage sludge the gasification process can become instable because of the very high ash content and low ash fusion temperatures of SS. At an equivalent ratio of 0.25, compared with wood pellets gasification, the addition of sewage sludge led to a reduction of gas yield in favor of an increase of condensate production with consequent cold gas efficiency decrease. Low concentrations of dioxins/furans and PAHs were measured in the gas produced by SS gasification, well below the limiting values for the exhaust gaseous emissions. NH(3), HCl and HF contents were very low because most of these compounds were retained in the wet scrubber systems. On the other hand, high H(2)S levels were measured due to high sulfur content of SS. Heavy metals supplied with the feedstocks were mostly retained in gasification solid residues. The leachability tests performed according to European regulations showed that metals leachability was within the limits for landfilling inert residues. On the other hand, sulfate and chloride releases were found to comply with the limits for non-hazardous residues., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This study was aimed at evaluating the effects of gasoline-ethanol blends on the exhaust emissions in a catalyst-equipped four-stroke moped engine. The ethanol was blended with unleaded gasoline in at percentages (10, 15, and 20% v/v). The regulated pollutants and the particulate matter emissions were evaluated over the European ECE R47 driving cycle on the chassis dynamometer bench. Particulate matter was characterized in terms of total mass collected on filters and total number ofparticles in the range 7 nm-10 microm measured by electrical low-pressure impactor (ELPI). In addition, particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions were evaluated to assess the health impact of the emitted particulate. Finally, an accurate morphological analysis was performed on the particulate by high-resolution transmission electron microscope (TEM) equipped with a digital image-processing/data-acquisition system. In general, CO emission reductions of 60-70% were obtained with 15 and 20% v/v ethanol blends, while the ethanol use did not reduce hydrocarbon (HC) and NOx emissions. No evident effect of ethanol on the particulate mass emissions and associated PAHs emissions was observed. Twenty-one PAHs were quantified in the particulate phase with emissions ranging from 26 to 35 microg/km and benzo[a]pyrene equivalent (BaPeq) emission factors from 2.2 to 4.1 microg/km. Both particulate matter and associated PAHs with higher carcinogenic risk were mainly emitted in the submicrometer size range (<0.1 microm). On the basis of the TEM observations, no relevant effect of the ethanol use on the particulate morphology was evidenced, showing aggregates composed ofprimary particles with mean diameters in the range 17.5-32.5 nm.

The use of heavy oil fly ash with high ash content (45 wt.%) as a precursor for the preparation of activated carbons has been investigated. The raw fly ash and the fly ash with lower ash content, obtained by a HCl/HF washing treatment, have been pyrolyzed at 900 degrees C and then activated with CO(2) in the temperature range of 800-900 degrees C for different times. The activated carbons have been characterised as regards the surface area and the pore volume. The evolution of the porosity has been related to the burn-off degree.