Search Results (652)

Effective in situ H₂S removal is essential for the utilization of small, remote natural gas wells, where centralized treatment is often unfeasible. This study presents an integrated environmental–economic assessment of two such processes, LO-CAT^® and triazine-based absorption, using a scenario-based framework. Environmental impacts were assessed via the Waste Reduction Algorithm (WAR), considering both Potential Environmental Impact (PEI) generation and output across eight categories, while economic performance was analyzed based on equipment, chemical, energy, environmental treatment, and labor costs. Results show that the triazine-based process offers superior environmental performance due to lower toxic emissions, whereas LO-CAT^® demonstrates better economic viability at higher gas flow rates and H₂S concentrations. An integrated assessment combining monetized environmental impacts with economic costs reveals that the triazine-based process becomes competitive only if environmental impacts are priced above specific thresholds. This study contributes a practical evaluation framework and scenario-based dataset that support sustainable process selection for decentralized sour gas treatment applications. Full article

This review summarises the possible applications and basic methodologies for the synthesis of six-membered polyazo heterocycles, namely, diazines, triazines, and tetrazines. The time period covered by the analysed works ranges from the beginning of the 20th century to the present day. This period was chosen because it was during this time that synthetic chemistry, as defined by physicochemical research methods, became capable of solving such complex problems as efficiently as possible. The first part of the review describes the applications of polyazo heterocyclic compounds, whose frameworks are found in the composition of drugs, dyes, and functional molecules for materials chemistry, as well as in a wide variety of natural compounds and their synthetic analogues. The review also systematises the methods for assembling six-membered aromatic polyazo heterocycles, including intramolecular and sequential cyclisation, which determine the possible structural and functional diversity based on the presence and arrangement of nitrogen atoms and the position of the corresponding substituents. Full article

Nanofiltration (NF) is considered a competitive purification method for acidic stream treatments. However, conventional thin-film composite NF membranes degrade under acid exposures, limiting their applications in industrial acid treatment. For example, wet-process phosphoric acid contains impurities of multivalent metal ions, but NF membrane technologies for impurity removal under harsh conditions are still immature. In this work, we develop a novel strategy of acid-resistant nanofiltration membranes based on interfacial polymerization (IP) of polyethyleneimine (PEI) and cyanuric chloride (CC) with the s-triazine ring. The IP process was optimized by orthogonal experiments to obtain positively charged PEI-CC membranes with a molecular weight cut-off (MWCO) of 337 Da. We further applied it to the approximate industrial phosphoric acid purification condition. In the tests using a mixed solution containing 20 wt% P₂O₅, 2 g/L Fe³⁺, 2 g/L Al³⁺, and 2 g/L Mg²⁺ at 0.7 MPa and 25 °C, the NF membrane achieved 56% rejection of Fe, Al, and Mg and over 97% permeation of phosphorus. In addition, the PEI-CC membrane exhibited excellent acid resistance in the 48 h dynamic acid permeation experiment. The simple fabrication procedure of PEI-CC membrane has excellent acid resistance and great potential for industrial applications. Full article

Microplastics (MPs) and nanoplastics (NPs) can affect microbial abundance and activity, likely by damaging cell membrane components. While their effects on anaerobic digestion are known, less is understood about their impact on microbes involved in contaminant bioremediation. Chlorinated volatile organic contaminants (CVOCs) such as tetrachloroethene (PCE) and explosives like hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) are common in the environment, and their bioremediation is a promising cleanup strategy. This study examined how polystyrene (PS) and polyamide 6 (PA6) MPs and NPs influence CVOC and RDX biodegradation. PS particles did not inhibit the CVOC-degrading community SDC-9, but PA6 MPs impaired the reductive dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (cis-DCE), causing a “cis-DCE stall” with no further conversion to vinyl chloride (VC) or ethene. Only 45% of TCE was dechlorinated to cis-DCE, and Dehalococcoides mccartyi abundance dropped 1000-fold in 35 days with PA6 MPs. In contrast, neither PA6 nor PS MPs and NPs affected RDX biotransformation. These results highlight the significant impact of PA6 MPs on CVOC biodegradation and the need to consider plastic pollution in environmental management. Full article

Covalent triazine frameworks (CTFs) have gained recognition as stable porous organic polymers, for example, for CO₂ separation. From the monomer 4,4′-(phenazine-5,10-diyl)dibenzonitrile (pBN), new pBN-CTFs were synthesized using the ionothermal method with a variation in temperature (400 and 550 °C) and the ZnCl₂-to-monomer ratio (10 and 20). N₂ adsorption yielded BET surface areas up to 1460 m²g ⁻¹. The pBN-CTFs are promising CO₂ adsorbents and are comparable to other benchmark CTFs such as CTF-1 with a CO₂ uptake of pBN-CTF-10-550 at 293 K of up to 54 cm³ g⁻¹ or 96 mg g⁻¹, with a CO₂/CH₄ IAST selectivity of 22 for a 50% mixture of CO₂/CH₄. pBN-CTF-10-400 has a very high heat of adsorption of 79 kJ mol⁻¹ for CO₂ near zero coverage in comparison to other CTFs, and it also stays well above the liquefaction heat of CO₂ due to its high microporosity of 50% of the total pore volume. Full article

Hybrid materials based on porous organic polymers (POPs) and metal–organic frameworks (MOFs) are increasing attention for advanced separation processes due to the possibility to combine their properties. POPs provide high surface areas, chemical stability, and tunable porosity, while MOFs contribute a high variety of defined crystalline structures and enhanced separation characteristics. The combination (or hybridization) with PIMs gives rise to mixed-matrix membranes (MMMs) with improved permeability, selectivity, and long-term stability. However, interfacial compatibility remains a key limitation, often addressed through polymer functionalization or controlled dispersion of the MOF phase. MOF/COF hybrids are more used as biochemical sensors with elevated sensitivity, catalytic applications, and wastewater remediation. They are also very well known in the gas sorption and separation field, due to their tunable porosity and high electrical conductivity, which also makes them feasible for energy storage applications. Last but not less important, hybrids with other POPs, such as hyper-crosslinked polymers (HCPs), covalent triazine frameworks (CTFs), or conjugated microporous polymers (CMPs), offer enhanced functionality. MOF/HCP hybrids combine ease of synthesis and chemical robustness with tunable porosity. MOF/CTF hybrids provide superior thermal and chemical stability under harsh conditions, while MOF/CMP hybrids introduce π-conjugation for enhanced conductivity and photocatalytic activity. These and other findings confirm the potential of MOF-POP hybrids as next-generation materials for gas separation and carbon capture applications. Full article

Background/Objectives: Inflammation is a crucial and complex mechanism that protects the body against infections. In our study, we propose to provide scientific evidence for the anti-inflammatory properties of 1,3,5-triazine derivatives. Methods: Initially, we ensured the safety of the three synthesized derivatives by administering graded doses of up to 2000 mg/kg intraperitoneally in Wistar rats. Thus, the three derivatives were considered generally safe. We also evaluated their ability to reduce carrageenan-induced rat paw edema. Results: Compounds 1, 2, and 3 demonstrated stronger anti-inflammatory activity than indomethacin (10 mg/kg), achieving maximum inhibition at the fourth hour with percentages of 96.31%, 72.08%, and 99.69%, respectively, at a dose of 200 mg/kg, compared to 57.66% for the standard drug. To explore the mechanism, levels of pro-inflammatory cytokines (TNF-α, IL-1α, IL-1β, IL-6, CRP) and oxidative stress markers were measured in paw tissue. All three compounds significantly reduced these markers more effectively than indomethacin and enhanced antioxidant levels (SOD and GSH) beyond those achieved by the standard treatment. Additionally, the compounds reduced COX-1 and COX-2 levels to values comparable to those in the normal (non-inflamed) control group. Conclusions: Compounds 1, 2, and 3 at doses of 200 mg/kg significantly (p  < 0.05) inhibited the heat-induced hemolysis of red blood cell (RBC) membranes by 94.6%, 93.9%, and 95.2%, respectively, compared to 94.5% produced by indomethacin. Consequently, we concluded that 1,3,5-triazine derivatives are a safe antioxidant agent with significant anti-inflammatory activity. Full article

Chiral covalent organic frameworks (COFs) hold great promise in heterogeneous asymmetric catalysis due to their designable structures and well-defined chiral microenvironments. However, precise control over the pore size of chiral COFs to optimize asymmetric catalytic performance remains challenging. Herein, we designed a proline-derived dihydrazide chiral monomer (L-DBP-Boc), which was subjected to Schiff-base reactions with two aromatic aldehydes of different lengths, 1,3,5-triformyl phloroglucinol (BTA) and 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)tribenzaldehyde (TZ), to construct two hydrazone-linked chiral COFs with distinct pore sizes (L-DBP-BTA COF and L-DBP-TZ COF). Interestingly, the Boc protecting groups were removed in situ during COF synthesis. We systematically investigated the catalytic performance of these two chiral COFs in asymmetric aldol reactions and found that their pore sizes significantly influenced both catalytic activity and enantioselectivity. The large-pore L-DBP-TZ COF (pore size: 3.5 nm) exhibited superior catalytic performance under aqueous conditions at room temperature, achieving a yield of 98% and an enantiomeric excess (ee) value of 78%. In contrast, the small-pore L-DBP-BTA COF (pore size: 2.0 nm) showed poor catalytic performance. Compared to L-DBP-BTA COF, L-DBP-TZ COF demonstrated a 1.69-fold increase in yield and a 1.56-fold enhancement in enantioselectivity, possibly attributed to the facilitated diffusion and transport of substrates and products within the larger pore, thus improving the accessibility of active sites. This study presents a facile synthesis of pyrrolidine-functionalized chiral COFs and establishes the possible structure–activity relationship in their asymmetric catalysis, offering new insights for the design of efficient chiral COF catalysts. Full article

Rationally designing and synthesizing chemosensors capable of simultaneously detecting both anions and cations via water content modulation is challenging. In this study, we synthesized and characterized a novel triazine calixarene derivative-based iodide and copper ion-selective fluorescent “turn-off” sensor. This dual-channeled fluorescent probe is able to recognize Cu²⁺ and I⁻ ions simultaneously in aqueous systems. The fluorescent sensor s4 was synthesized by displacement reaction of acridine with 1, 3-bis (dichloro-mono-triazinoxy) benzene in acetonitrile. Mass spectrometry (MS), UV-vis, and fluorescence spectra were acquired to characterize the fluorescence response of s4 to different cations and anions, while infrared (IR) spectroscopy and isothermal titration calorimetry (ITC) were employed to study the underlying selectivity mechanism of s4 to Cu²⁺ and I⁻. In detail, s4 displayed extremely high sensitivity to Cu²⁺ with over 80% fluorescence decrement caused by the paramagnetic nature of Cu²⁺ in the aqueous media. The reversible fluorescence response to Cu²⁺ and the responses to Cu²⁺ in the solution of other potential interferent cations, such as Li⁺, Na⁺, K⁺, Ca²⁺, Cd²⁺, Zn²⁺, Sr²⁺, Ni²⁺, Co²⁺ were also investigated. Probe s4 also exhibited very good fluorescence selectivity to iodide ions under various anion (F⁻, Cl⁻, Br⁻, NO₃⁻, HSO₄⁻, ClO₄⁻, PF₆⁻, AcO⁻, H₂PO₄⁻) interferences. In addition to the fluorescent response to I⁻, s4 showed a highly selective naked-eye-detectable color change from colorless to yellow with the other tested anions. Full article

The design of suitable chemosensors for environmental pollutants and toxins detection at trace levels remains a critical area of research. Among various chemosensors, Zn(II) coordination polymers have garnered special interest as fluorescent probes for environmental applications. In this article, we report the synthesis of a nitrogen-rich luminescent Zn(II) coordination polymer, TDPAT-Zn-CP, designed for differential fluorescent sensing of antibiotics in an aqueous medium. TDPAT-Zn-CP was synthesized using a star-shaped 2,4,6-tris(di-2-pyridylamino)-1,3,5-triazine (TDPAT) fluorophore, a promising blue-emitting compound. The morphological and structural properties of TDPAT-Zn-CP were thoroughly analyzed using conventional spectroscopic and analytical techniques. The fluorescence titration studies in aqueous medium demonstrated that TDPAT-Zn-CP exhibits remarkable selectivity, sensitivity, and differential fluorescence sensing responses towards various antibiotics. Among the antibiotics tested, TDPAT-Zn-CP displayed a significant fluorescence quenching and high selectivity for sulfamethazine (SMZ), with a Stern–Volmer quenching constant of K_SV = 1.68 × 10⁴ M⁻¹ and an impressive sensitivity of 4.95 ppb. These results highlight the potential of TDPAT-Zn-CP as a practically useful, highly effective polymeric sensor for the differential fluorescence-based detection of antibiotics in water, offering a promising approach for environmental monitoring and contamination control. Full article

Hydroformylation is one of the most widely applied homogeneous catalytic processes in the chemical industry, constituting the predominant manufacturing platform for aldehyde synthesis at commercial scales. Nevertheless, hydroformylation shares with traditional homogeneous catalysis the inherent limitation of difficult catalyst recovery and recycling. Developing heterogeneous catalysts for such reactions is thus critically needed. Herein, a stable nitrogen-rich covalent triazine framework (CTF) was synthesized via a mild Friedel–Crafts alkylation method and employed as a support for Rh single-atom catalysts (Rh/CTF-TPA). In the hydroformylation of 1-decene, the Rh/CTF-TPA catalyst exhibits an exceptional reaction efficiency (TOF > 1900 h⁻¹), outperforming the homogeneous Rh(CO)₂(acac). Experimental and characterization results revealed that the CTF support enhances catalytic performance through two key mechanisms: (1) strong enrichment of reactants within its special structure, and (2) efficient dispersion of Rh single-atom sites stabilized by abundant nitrogen coordination. This work demonstrates a rational design strategy for heterogeneous hydroformylation catalysts by leveraging nitrogen-rich porous frameworks to synergistically optimize metal anchoring and reactant enrichment, offering a promising alternative to conventional homogeneous systems. Full article

Covalent triazine frameworks (CTFs) are a class of porous organic semiconductors containing a large number of triazine units, which gives them many properties suitable for photocatalysis, such as high porosity, good tunability, and excellent chemical stability. However, it is difficult to achieve high activity, stability, and selectivity at the same time using a single CTF in a specific catalytic reaction. Therefore, it is necessary to find ways to combine CTFs with other materials to improve their photocatalysis activity. From this perspective, some construction methods and the latest progress of CTF-based composites are presented, and their applications in the field of photocatalysis are introduced. Finally, the future of CTF materials in catalytic applications is proposed, which provides some insights into the research and exploration of CTF-based composites. Full article

Colorectal cancer (CRC) remains a major global health challenge, necessitating the development of more effective and environmentally sustainable treatments. This study presents a novel green synthetic protocol for 1,3,5-triazine derivatives with anticancer potential, employing both microwave-assisted and ultrasound-assisted methods. The synthesis was optimized using 4-chloro-N-(2-chlorophenyl)-6-(morpholin-4-yl)-1,3,5-triazin-2-amine as the key intermediate, with sodium carbonate, TBAB, and DMF providing optimal yields under microwave conditions. To enhance sustainability, a modified sonochemical method was also developed, enabling efficient synthesis in aqueous media with a minimal use of organic solvents. A series of nine morpholine-functionalized derivatives were synthesized and evaluated for cytotoxic activity against SW480 and SW620 colorectal cancer cell lines. Compound 11 demonstrated superior antiproliferative activity (IC₅₀ = 5.85 µM) compared to the reference drug 5-fluorouracil, while compound 5 showed promising dual-line activity. In silico ADME analysis supported the drug likeness of the synthesized compounds, and biomimetic chromatography analysis confirmed favorable physicochemical properties, including lipophilicity and membrane affinity. These results underscore the potential of the developed protocol to produce bioactive triazine derivatives through an efficient, scalable, and environmentally friendly process, offering a valuable strategy for future anticancer drug development. Full article

Detecting heavy metal ions is essential for maintaining environmental safety, ensuring industrial quality control, and protecting public health. In this study, we have synthesized a novel Rhodamine B-based fluorescent probe, RhB-DCT, which is functionalized with 2,4-dichloro-1,3,5-triazine (DCT) to enhance selectivity and sensitivity for metal ions detection. The probe functions through a “turn-on” fluorescence mechanism activated by the opening of the spiro-lactam ring induced by Fe³⁺ ions, resulting in a distinct color change from colorless to deep pink. The RhB-DCT probe demonstrated a rapid and robust fluorescence response within seconds, exhibited a broad pH stability from 4 to 13, showed excellent reversibility, and possessed a low detection limit of 0.0521 μM, surpassing numerous existing fluorescent probes. The RhB-DCT probe exhibited significant selectivity for Fe³⁺ than other competing metal ions. The integration of high sensitivity, rapid response, and strong stability positions RhB-DCT as a viable option for real-time detection of Fe³⁺ ions in aqueous settings. This study demonstrates the efficacy of the RhB-DCT probe in environmental monitoring, water quality assessment, and analytical sensing platforms, serving as an effective and dependable tool for detecting heavy metal ions. Full article

In Romania, groundwater is an important source of drinking water, especially in rural areas. This study investigated the concentrations of organophosphorus, carbamate, and triazine pesticides (OPs) along with organochlorine pesticides (OCPs) in groundwater samples collected from the Titu-Sarata Plain. Sensitive analytical techniques were employed, including Ultrahigh-Performance Liquid Chromatography coupled with Q Exactive™ HF Hybrid Quadrupole-Orbitrap™ Mass Spectrometry (UHPLC-Orbitrap-MS/MS) and Gas Chromatography coupled with an electron capture detector (GC-ECD). Environmental and human health risks were assessed in the case of pesticides that exceeded the maximum allowed concentration. The environmental risk assessment (ERA) revealed significant risks associated with Phosdrin, Phorate, and pp’DDE. Additionally, particular concerns arose from the presence of Aldrin and Dieldrin, which pose a high carcinogenic risk, especially through groundwater consumption in agricultural areas. The results of this research highlight the need for the implementation of a continuous quality monitoring program for groundwater in the agricultural regions that were studied. Full article