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This work reports the design of binary and ternary BiOI-based composites incorporating the metal–organic framework CAU-17 and the amine-functionalized microporous organic polymer MOP-CH2EDA for the removal of ciprofloxacin (CIP) from water. The materials were synthesized via an in situ solvothermal approach and systematically characterized to establish structure–property relationships. The results reveal that adsorption and photocatalysis act as coupled and sequential processes, rather than independent pathways, with the polymer component enhancing CIP pre-concentration and the BiOI/MOF interface governing photodegradation. The ternary composite BCM-10% exhibited the best performance, achieving up to 80% CIP removal under simulated solar irradiation. Scavenger experiments indicate that ·O2− is the dominant reactive species, while photogenerated holes also contribute significantly. The degradation process is strongly influenced by pH, reflecting the interplay between catalyst surface properties, reactive oxygen species generation, and CIP speciation. HPLC-MS analysis confirms the formation of multiple intermediates and highlights the complexity of the degradation pathways. Despite the improved performance of the ternary composites, the overall activity remains moderate compared to state-of-the-art photocatalysts, underscoring the limitations of current BiOI-based systems. The results emphasize that apparent kinetic behavior is strongly affected by adsorption contributions, complicating direct comparison with literature data. This study provides new insight into the design of multifunctional materials for water treatment, highlighting the importance of adsorption–photocatalysis synergy and the need for more rigorous and standardized evaluation of photocatalytic systems.

Removal of pharmaceuticals from wastewater remains a major environmental challenge, requiring efficient and selective Advanced Oxidation Processes (AOPs). Catalytic and non-catalytic ozonation was investigated in a laboratory-scale reactor under optimized flow conditions (500–750 mL min⁻¹, 98 % O₂ feed). Ozonation kinetics of active pharmaceutical ingredient mixtures (APIs) consisting of ibuprofen (IBU), diclofenac (DCF), carbamazepine (CBZ), sulfadiazine (SDZ), and sulfamethoxazole (SFX) (40 mg L⁻¹ each) — was investigated using iron-modified zeolite catalysts, Fe-H-Y and Fe-H-Beta, under semi-batch operations (0.5 g catalyst, 20 °C) in order to correlate degradation and mineralization efficiency with catalyst structure, acidity, and stability. Both catalysts significantly improved the ozone utilization compared to non-catalytic ozonation. Interestingly, Fe-H-Y accelerated initial degradation rate, while the use of Fe-H-Beta resulted in the highest level of mineralization. Adsorption–desorption analysis revealed that the molecular size and polarity controlled the interactions between the pharmaceutical and the catalyst: smaller polar compounds (SDZ, SFX) exhibited stronger adsorption on the catalyst, while bulkier molecules (DCF, IBU) were restricted to external surfaces. Post-reaction characterization confirmed that the Fe-H-Y retained more surface area and exhibited lower Fe leaching, while Fe-H-Beta showed significantly higher carbon deposition. Overall, Fe-H-Y combined rapid kinetics and structural stability, while Fe-H-Beta provided higher mineralization, at the expense of more extensive fouling. The study demonstrated that optimized ozonation conditions, coupled with tailored zeolite catalysts, markedly improve the oxidation efficiency and long-term performance in the oxidation of pharmaceuticals.

Here, we introduce three new halogen-free salts based on the green, sustainable, and hydrolytically stable saccharinate (Sac) anion, and their deep eutectic solvents (DESs) with ethylene glycol (EG). All the three salts exhibit distinct and well-defined thermal behaviors, ranging from ionic plastic crystals (IPCs) to supercooled liquids and classical ionic liquids (ILs). In contrast, their corresponding DESs display no detectable thermal events, a clear indication of successful DES formation, which is well supported by FTIR spectroscopy and suggests that EG interacts with the −CO and −SO2 groups of the Sac anion. DES with [EMPip][Sac] offers superior ion transport and electrochemical properties, supporting a voltage range up to 5.7 V, and as an electrolyte in a symmetric supercapacitor, a specific capacitance of 46.5 F g−1at 5 mV s−1, an energy density of 9.9 Wh kg−1, and power density of 1022 W kg−1, at a current density of 0.2 A g−1. The capacitor retained 99 % of its initial capacitance after 20,000 cycles at ambient temperature. Altogether, these halogen-free DES electrolytes offer promising electrochemical properties, making them ideal electrolytes for supercapacitors operating at ambient temperatures over a wide potential range.

Fluorine-free supercapacitor (SCs) electrolytes are desirable to minimize environmental impact and toxicity while maintaining high electrochemical performance and long-term sustainability. Here, we introduce the new class of fluorine-free ionic liquids (ILs) engineered around the unique electron-deficient triazine-derived anion, 4,6-diethoxy-2-oxo-2H-1,3,5-triazin-5-ide (DET), coupled with n-tetrabutyl- phosphonium and ammonium cations. Both the ILs exhibit distinct and well-defined thermal behaviors, the former behaves as a glass-forming liquid, that is, have glass transition at −63 °C, while the latter exists as a supercooled liquid with complex thermal events and is ca. 90 K less thermally stable. We find relatively weaker cation–anion interactions – well supported by the FTIR data – and, thus higher ionic conductivity and higher electrochemical stability, with supporting voltage range up to 4.4 V, for (P4444)(DET) than in (N4444)(DET). (P4444)(DET) as SCs electrolyte delivers excellent capacitive performance within the 2.0 V window at 30 °C and 60 °C. The device achieved areal capacitance of 78 mF cm−2(at 0.146 mA cm−2) and gravimetric capacitance of 60.6 F g−1(at 0.15 A g−1) at 60 °C and delivered an energy density of 34.6 Wh kg−1and the power density of 1873 W kg−1while maintaining ∼94% capacitance retention and ∼98% coulombic efficiency after 1000 cycles. SCs.

The catalytic conversion of CO2 into methane (CH4) offers a sustainable solution to the worsening global warming scenario, especially for controlling CO2 levels. This study reports silicalite-1 supported Ni catalysts with different loadings for CO2 conversion to CH4, prepared via wet impregnation. The X-ray diffraction pattern revealed an increase in crystallite size at higher Ni loadings, which was further supported by N2 sorption, where the specific surface area and microporosity of the catalysts were decreased. There was a slight shift in the reducibility of the catalysts, potentially indicating the impact of loading on dispersion and spatial distribution. The catalyst performance was evaluated over a range of temperatures at 5 bar and a GHSV of 20,000 mL gcat-1 h-1. Surprisingly, the Ni(5)@Silicalite-1 exhibited higher CO2 conversion efficiency across the range of temperatures compared to Ni(10)@Silicalite-1. The NiO(5)@Silicalite-1 demonstrated a maximum CO2 conversion of 88% at 450 °C, which was approximately 14% higher than that of the catalyst with a 10 wt.% loading. Notably, the CH4 selectivity pattern was quite identical across the catalysts, underscoring that the reaction pathways were unaffected by the loadings. The higher performance of NiO(5)@Silicalite-1 could be ascribed to smaller NiO crystallites and improved textural properties.

Two novel, structurally different perfluoroalkyl ionic liquids with bicyclic guanidinium cation have been synthesized and applied as a surfactant component for selected active pharmaceutical ingredients (APIs). The addition of perfluoroalkyl ionic liquid to hydrophobic APIs significantly improves their solubility. One of the key and characteristic properties of guanidine derivatives is their strong ability to chemisorb protons (proton affinity). This property enables them to form stable ionic-type aggregates (adducts) with selected hydrophobic APIs containing carboxylic groups. Therefore, these new compounds are, in fact, API-IL ionic adducts formed as hydrogen bond donor–acceptor systems. The obtained adducts are characterized by significantly better solubility than the initial APIs. The presence of perfluoroalkyl chains with unique surface-active properties enables to obtain a solubility of new adducts to reach level sufficient for typical ophthalmic preparations. (e.g., eye drops or lens care). The ionic API-IL adducts obtained in the described studies can be considered as examples of a new class of active derivatives with pharmaceutical potential.

Herein, a Ru-decorated carbon material bearing unique surface chemistry (Brønsted acidic phosphate groups, Lewis basic N-groups and oxygen functional groups) is shown to exhibit exceptional activity, selectivity and stability upon direct hydrogenation of aqueous levulinic acid (LA) (0.47 M and 0.95 M) to γ-valerolactone (GVL) under mild conditions (25–95 °C and 3.5–5 bar). The multifunctional Ru/carbon catalyst outperformed the bifunctional Ru/NbOPO4, and blended (physically mixed) catalytic systems comprising of commercial Ru/carbon (hydrogenation catalyst) and NbOPO4/Amberlyst 15 (acid promoter/co-catalyst). The material also demonstrated remarkable stability for energy efficient GVL production in a fixed-bed reactor under continuous flow conditions, maintaining stable GVL productivity during 52-day time on stream operating at 3.5–5 bar, 80–95 °C and low H2/LA ratio (4–17:1 mol/mol). The exceptional catalytic performance and long term stability of the multifunctional carbocatalyst was attributed to the presence of highly active Ru(0) nanoparticles stabilized on N-doped carbon framework and acidic phosphates and RuOx/RuO2 sites, which promote LA hydrogenation and intramolecular esterification of 4-hydroxypenatonnic (4-HPA) in tandem, affording a high GVL selectivity. The catalyst's combination of high productivity, long-term stability, and ability work under intensified setting in mid conditions highlight its potential for energy efficient GVL production at large scale.

NbOPO4 supported TiO2 materials were demonstrated to be excellent catalysts for selective conversion of C6-carbohydrates to 5-hydroxymethylfurfural in an environmentally benign dimethyl carbonate-water solvent system. The materials presented high activity and excellent stability in sub-critical water conditions (upto 180 °C and 20 bar), enabling continuous 5-hydroxymethylfurfural production from highly concentrated sugars (35 wt% fructose, glucose and glucose:fructose mixtures) in a micro fixed-bed reactor. The high catalytic activity (6–27.3 KgHMFKgCat−1day−1) and good-to-excellent HMF selectivity (55–91 %) and exceptional hydrolytic stability and regenerability observed under process conditions was attributed to a highly crystalline NbOPO4 phase with Q2 and Q3 phosphates stabilized on a TiO2 framework with tunable acidity (0.11–0.52 mmolH+g−1 and Brønsted/Lewis ratio) and acidic strength comparable to bulk-NbOPO4. Furthermore, our experiments also revealed the importance of organic solvents in modulating catalyst acidic properties, particularly the strength of Brønsted acid sites which, in turn, influenced the HMF productivity.

Water pollutants such as synthetic dyes can cause significant problems for human health and ecosystems due to their chemical properties and environmental interactions. Contamination of surface and underground water caused by the discharge of synthetic dyes is a widespread problem that arises primarily from industrial activities such as textile manufacturing, leather processing, paper production, and plastics industries. Since adsorption is one of the most efficient and reliable methods to remove pollutants from water, in this work, pine tree logging residues (LR) were used to produce boron/sulfur chemically modified biochars with superior adsorption performance and recyclability. The biochars were produced using a two-step pyrolysis procedure with potassium hydroxide as a chemical activator. The specific surface areas (B.E.T.) of the biochars were 2645 m2 g−1 for the boron-treated biochar (LR-Boron), 2524 m2 g−1 for the sulfur-treated (LR-Sulfur), and 3141 m2 g−1 for the control biochar (LR-Control, without boron or sulfur), respectively. The LR-Boron biochar showed an exceptional degree of graphitization of (ID/IG=0.45), while the LR-Sulfur biochar displayed an ID/IG= 1.02; for comparison, the LR-Control exhibited an ID/IG= 0.81, showing that the sample subjected to boron treatment created carbon-rich in graphitic structures. The three biochars were evaluated as adsorbents for removing reactive black-5 azo dye (RB-5) from water and mixtures of several dyes in synthetic aqueous effluents. The adsorption data showed that all carbons exhibited outstanding RB-5 removal performance. Kinetic measurements were well fitted by the Avrami fractional order model, and the LR-sulfur carbon displayed the fastest adsorption kinetics. Isotherm measurements were well fitted by the Liu model, with a theoretical Qmax of around 1419 mg g−1 (LR-Control), 1586 mg g−1 (LR-Boron), and 1766 mg g−1 (LR-Sulfur) at 316 K. The presence of sulfur-functional groups on the LR-Sulfur biochar surface was probably the reason for the superior adsorption performance of this biochar. Both sulfur and boron-treated biochars exhibited higher regeneration potentials, maintaining around 60–67 % removal capacity after 7 cycles compared to 35 % for the LR-Control biochar. Thermodynamic adsorption studies showed that the adsorption process was endothermic, favorable, and compatible with physical adsorption. All produced biochars were highly efficient for removal of pollutants from concentrated synthetic effluents.

Triglycerides or vegetable oils as fuels is an old idea that can be traced back to the early days of diesel engine development. In this chapter, an overview of the fuel properties of triglycerides and their various upgrading technologies (physical and chemical; catalytic or non-catalytic) are discussed. Moreover, the composition of various feedstocks, the various catalyst materials employed in triglyceride upgrading, and the influence of the support materials, as well as sulfide and other promoters or feed impurities, are briefly discussed. Finally, a number of important large-scale, commercial processes in renewable-diesel production are reviewed and general operating strategies are discussed. In general, it can be concluded that deoxygenative transformation of triglycerides seems to be the most effective, enabling direct production of drop-in hydrocarbon fuels (green diesel or green jet fuels). In summary, significant possibilities still exist for further development of improved deoxygenation technologies that aim to improve the commercial feasibility of processing triglycerides into green hydrocarbon fuels of tomorrow.