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The hydrothermal liquefaction reactions (HTL) in subcritical conditions of a lignin residue has been studied on a lab scale. The starting material was a lignin rich residue co-produced by an industrial plant situated in Northern Italy producing lignocellulosic bioethanol. The reactions were carried out in batch mode using stainless steel autoclaves. The experiments were under the following operating conditions: two different temperatures (300–350 °C), the presence of basis catalysts (NaOH, and NH 4 OH) in different concentrations and the presence/absence of capping agent 2,6-bis-(1,1-dimethylethyl)-4-methylphenol (BHT). Lignin residue and reaction products were characterized by analytical and spectroscopic techniques such as CHN-S, TGA, GC–MS, EPR, and 1 H-NMR with (2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (T.E.M.P.O.). The addition of BHT did not significantly affect the yield of char which is formed by radical way. Spectroscopic analysis indicated that the level of radicals during the reaction was negligible. Therefore, the results obtained experimentally suggest that the reaction takes place via an ionic route while radical species would play a minor role.

End of life packaging is nowadays one of the major environmental problems due to its short usage time, the low biodegradability, and the big volume occupied. In this context, gasification is one of the most promising chemical recycling techniques. Some non-recyclable or non-compostable waste gasification plants are already operating such as Enerkem Alberta Biofuels in Canada or the Sierra’s FastOx Pathfinder in California. In this review, we have examined works about plastic gasification from the last fifteen years with a specific focus on polyolefin (PP, PE), plastics mix, and co-gasification of plastic with biomass. For each of these, the best operating conditions were investigated. A very in-depth section was dedicated to supercritical water gasification (SCWG). The most used reactors in gasification processes are fluidized bed reactors together with air or steam as gasifying agents. Tar removal is commonly performed using olivine, dolomite, or nickel based catalysts. SCWG has numerous advantages including the inhibition of tar and coke formation and can be used to remove microplastics from the marine environment. In co-gasification of plastic material with coal or biomass, synergistic effects are observed between the raw materials, which improve the performance of the process, allowing to obtain higher gas yields and a syngas with a high energy content.

In this study, we investigate the hydrothermal liquefaction (HTL) of PET separated from a densified postconsumer plastic mix, with the aim of recovering its monomer. This second raw material is made up of 90% polyolefin, while the remaining 10% is made up of PET, traces of metals, paper, and glass. After preliminary separation by density in water, two batch experiments were performed on the sunken fraction (composed mainly of PET) in a stainless steel autoclave at 345 °C for 30 and 20 min. Both trials resulted in similar yields of the three phases. In particular, the solid yield is around 76% by weight. After a purification step, this phase was analyzed by UV–Vis, 1H-NMR, and FTIR spectroscopy and resulted to be constituted by terephthalic acid (TPA), a product of considerable industrial interest. The study proved that the hydrothermal liquefaction process coupled with density separation in water is effective for obtaining TPA from a densified postconsumer plastic mix, which can be used for new PET synthesis.

In Sicily, many natural water bodies were reclaimed over the last two centuries for malaria control and agricultural expansion, causing widespread habitat loss. Some of these former ponds (still locally called “lakes”) reappear occasionally after extreme rainfall, temporarily restoring aquatic habitats but remaining poorly documented. We confirm the occurrence of such episodic ponds in central Sicily (Sommatino–Riesi) and present one of these ponds (Lago Montagna) as a case study. Combining satellite observations with field surveys conducted during a spring 2025 inundation, we document repeated episodes of flooding and a remarkable aquatic flora, including charophytes and other taxa of conservation interest. Episodic inundation events, therefore, act as transient refugia and stepping stones for regional biodiversity within an otherwise dry landscape. Because these systems commonly escape routine monitoring and legal protection, we argue they should be explicitly recognized in regional conservation planning and long-term monitoring programs. Moreover, the integrated remote-sensing approach used here allows the detection of overlooked temporary wetland ecosystems and provides fine-scale hydrological insights often missed by sparse weather station networks or satellite-derived rainfall data.

This study investigates the potential of rapeseed meal (RM), a protein-rich by-product of the rapeseed oil industry, as a raw material for the development of renewable materials. Due to the presence of antinutritional compounds, rapeseed meal is underutilized, primarily in low-value applications such as animal feed. In this work, rapeseed meal protein hydrolysates were enzymatically obtained and incorporated as plasticizers into rapeseed meal-based materials to improve their mechanical properties, water permeability, and thermal stability. Collagen hydrolysate has also been utilized as a low-cost additive to further enhance the material performance. The glycerol content was reduced to address permeability and migration issues associated with hydrophilic plasticizers. The results demonstrated that the incorporation of hydrolysates into rapeseed meal-based materials modulated thermal stability, water permeability, and mechanical properties—particularly elongation at break and flexibility. The latter increased proportionally with the hydrolysate content of RM-based materials. Additionally, aerobic biodegradation behavior, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) supported the material’s favorable performance characteristics, highlighting the potential of rapeseed meal as a viable, biodegradable alternative for sustainable materials in industrial applications.

Hydrothermal liquefaction of lignin-rich stream from lignocellulosic ethanol production at an industrial scale was carried out in a custom-made batch test bench. Light and heavy fractions of the HTL biocrude were collected following an ad-hoc developed two-steps solvent extraction method. A full factorial design of experiment was performed, investigating the influence of temperature, time and biomass-to-water mass ratio (B/W) on product yields, biocrude elemental composition, molecular weight and carbon balance. Total biocrude yields ranged from 39.8% to 65.7% w/w. The Temperature was the main influencing parameter as regards the distribution between the light and heavy fractions of the produced biocrude: the highest amount of heavy biocrude was recovered at 300 °C, while at 350 and 370 °C the yield of the light fraction increased, reaching 41.7% w/w at 370 °C. Instead, the B/W ratio did not have a significant effect on light and heavy biocrude yields. Feedstock carbon content was mainly recovered in the biocrude (up to 77.6% w/w). The distribution between the light and heavy fractions followed the same trend as the yields. The typical aromatic structure of the lignin-rich stream was also observed in the biocrudes, indicating that mainly hydrolysis depolymerization occurred. The weight-average molecular weight of the total biocrude was strictly related to the process temperature, decreasing from 1146 at 300 °C to 565 g mol−1 at 370 °C.

The aim of the present work is to investigate the possibility of producing activated carbons from the residual lignin stream of lignocellulosic ethanol biorefineries, as this represents an optimal opportunity to exploit a residual and renewable material in the perspective of sustainable bioeconomy, increasing biorefinery incomes by producing value-added bioproducts in conjunction with biofuels. Activated carbons (ACs) were produced via chemical (KOH) and physical (CO2) activation. Char samples were obtained by slow pyrolysis (SP) and hydrothermal carbonization (HTC). Several HTC experiments were carried out by varying residence time (0.5–3 h) and reaction temperature (200–270 °C), in order to evaluate their influence on the product yield and on the morphological characteristics of the hydrochar (specific surface area, total pore volume and pore size distribution). ACs from hydrochars were compared with those obtained from pyrochar (via physical activation) and from the raw lignin-rich stream (via chemical activation). In both cases, by increasing the HTC temperature, the specific surface of the resulting activated carbons decreased from 630 to 77 m2 g−1 for physical activation and from 675 to 81 m2 g−1 for chemical activation, indicating that an increase in the severity of the hydrothermal pretreatment is deleterious for the activated carbons quality. In addition, the HTC aqueous samples were analyzed, with GC-MS and GC-FID. The results suggest that at low temperatures the reaction mechanisms are dominated by hydrolysis, instead when the temperature is increased to 270 °C, a more complex network of reactions takes place among which decarboxylation.

Freshwater ecosystems are rapidly losing biodiversity due to anthropogenic and environmental pressures. Considering that many species remain unknown, these systems represent an invaluable reservoir of biodiversity. For this reason, a prompt biodiversity census becomes essential. Environmental DNA (eDNA) has the potential to provide a faster and non-invasive alternative to traditional methods for biodiversity monitoring, conservation, and management. This study used eDNA to provide a preliminary snapshot of vertebrates in two Sicilian lakes: Lake Rosamarina and Lake Garcia. eDNA analyses identified four classes of vertebrates, 14 orders, and 16 families, with notable taxonomic differences between the two lakes. The analysis revealed the presence of several non-native and potentially invasive species, including fish (Cyprinus carpio, Micropterus salmoides, Perca fluviatilis, Carassius auratus, and Ameiurus melas), as well as the amphibian Xenopus laevis and the terrestrial mammal Myocastor coypus. The presence of these species, known for their ecological impact on native communities, highlights the potential of eDNA analysis as a powerful tool for the early detection and preventive biomonitoring of biological invasions. These results provide an initial assessment of vertebrate biodiversity in these sites, demonstrating how eDNA can serve as an effective method for biodiversity evaluation and monitoring.

Hydrothermal depolymerization of lignin-rich streams (LRS) from lignocellulosic ethanol was successfully carried out in a lab-scale batch reactors unit. A partial depolymerization into oligomers and monomers was achieved using subcritical water as reaction medium. The influence of temperature (300–350–370 °C) and time (5–10 minutes) was investigated to identify the optimal condition on the monomers yields in the lighter biocrude (BC1) and aqueous phase (AP) fractions, focusing on specific phenolic classes as well as carboxylic acids and alcohols. The effect of base catalyzed reactions (2–4 wt. % of KOH) was compared to the control tests as well as to acid-catalyzed reactions obtained with a biphasic medium of supercritical carbon dioxide (sCO2) and subcritical water. KOH addition resulted in enhanced overall depolymerization without showing a strong influence on the phenolic generation, whereas sCO2 demonstrated higher phenolic selectivity even though no effect was observed on the overall products mass yields. In conclusion, a comparison between two different biocrude collection procedures was carried out in order to understand how the selected chemical extraction mode influences the distribution of compounds between BC1 and AP.

In recent years, there has been increasing interest in developing novel materials based on natural biopolymers as a renewable alternative to petroleum-based plastics. The availability of proteins derived from agricultural by-products, along with their favourable properties, has fostered a renewed interest in protein-based materials, promoting research in innovative technologies. In this study, we propose the use of rapeseed protein-rich meal as the main ingredient for the preparation of novel sustainable materials combining excellent environmental properties such as biodegradability and renewability. The application of sustainable products in the present high-tech society requires the modification of the basic native properties of these natural compounds. The original route proposed in this paper consists of preparation via the compression moulding of flexible biomaterials stabilized by crosslinkers/chain extenders. An investigation of the effects of different denaturing and disulfide bond reducing agents, crosslinkers, and preparation conditions on the material mechanical behaviour demonstrated that the novel materials have appreciable strength and stiffness. The results show the potential of utilizing full meal from vegetable by-products to prepare protein-based materials with guaranteed ecofriendly characteristics and mechanical properties adequate for specific structural applications.