Journal of the Iranian Chemical Society最新文献

A mild and efficient method for the solvent-free catalytic nitration of o-xylene (OX) employing silicon sulfonic acid (SSA) as a catalyst and NO₂ as a clean nitrating agent, leads to high selectivity for 4-nitro-o-xylene (4-NOX). Under optimal conditions, a 64.6% selectivity for 4-NOX and a 46.7% conversion of OX were achieved. The results showed that the enhanced OX conversion and target product selectivity were attributed to the synergistic catalysis of the combination of the SSA catalyst and the NO₂–O₂ system. The characterization results showed that the immobilized SSA, which is not only simple and economical to prepare but also exhibits excellent nitration activity, was effectively synthesized via the chemical bonding method. The highly dispersed sulfonic acid groups were covalently anchored to the surface of the silicon acid (SA), thereby enriching acid sites and stabilizing the catalytic performance. Additionally, a possible reaction mechanism for nitrating OX with NO₂–O₂ over the SSA catalyst was proposed. Compared with the traditional method, this study promotes the selectivity of the target product while reducing acidic wastewater streams, indicating potential application prospects.

The global reliance on bioenergy over recent decades has sparked environmental concerns, prompting a search for alternative and sustainable energy sources. Bioenergy emerges as a promising solution, fostering sustainable economic development, ensuring national energy security and mitigating environmental complications. This review undertakes a comprehensive examination of the bioenergy policy measures implemented by various agencies across different countries. The primary objective is to identify the obstacles that impede the sustainable growth of biofuels as a viable alternative fuel. Bioenergy promises to reduce GHG emissions and lessen dependence on finite fossil fuels; a comprehensive evaluation of its environmental, social, and economic impacts is necessary to determine its true sustainability. This critical review offers an in-depth examination of the multifaceted aspects of bioenergy, with a focus on its potential benefits and drawbacks. Environmental considerations underscore the importance of assessing the life cycle of bioenergy, including land use, biodiversity loss, and the emission of other pollutants during the cultivation, conversion, and utilisation processes. Furthermore, this review presents their insights to address the critical issues surrounding global bioenergy generation. The study aims to contribute to a more comprehensive understanding of the challenges and opportunities associated with biofuel adoption, ultimately fostering sustainable energy practices on a global scale.

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The widespread use of fluoroquinolone (FQ) antibiotics in both human and veterinary medicine has led to their identification as a new and persistent threat to aquatic ecosystems. Environmental hazards, public health concerns, and the spread of antibiotic resistance are all heightened by their impaired metabolism, inability to be treated by traditional wastewater treatment methods, and ongoing release. With an emphasis on the growing importance of lanthanum-based nanoparticles as sophisticated remediation agents, this review assesses the environmental occurrence, fate, toxicological effects, and removal methods of fluoroquinolones. This paper offers an in-depth investigation of the features, impacts on aquatic ecosystems, and remediation strategies of fluoroquinolones in environmental systems. This work concludes with a comparative, mechanistic evaluation of lanthanum-based nanomaterials for the removal of fluoroquinolones via adsorption and photocatalytic degradation. Their strong affinity, selectivity, structural adaptability, broad pH range, and reusability are rigorously assessed with respect to synthesis techniques and structure–performance correlations. Remaining problems, such as scalability, material stability, recovery, and possible environmental hazards, are also addressed. This analysis presents a cohesive approach connecting fluoroquinolone pollution with novel nanotechnological solutions. It offers recommendations for future material design and sustainable wastewater treatment strategies to reduce antibiotic contamination in aquatic ecosystems.

In the present work, the performance of monolayer (100) and (111) TaON nanosheets complexed with 4-[2-[4-(dimethylamino)phenyl]diazenyl]-benzoic acid (para-methyl red) dye molecules as dye-sensitized solar cells (DSSCs) was investigated and compared with that of the dye/(101) TiO₂ nanosheet complex using both periodic and non-periodic approaches. The calculated interaction and binding energies indicated that the dye/TaON nanosheet complexes are more stable than the dye/TiO₂ counterparts. Natural Bond Orbital (NBO) and Partial Density of States (PDOS) analyses revealed that the HOMO of the dye/nanosheet complexes is primarily composed of occupied orbitals of the dye molecule, while the LUMO is dominated by unoccupied orbitals of the nanosheets. Furthermore, the dye/(100) TaON nanosheet complex exhibited the narrowest band gap among the studied systems. These findings suggest that DSSCs synthesized by complexing the dye molecule with the (100) TaON nanosheet possess superior solar cell performance compared to those based on the dye/(101) TiO₂ nanosheet complex.

Chemocatalytic transformation of lignocellulosic biomass into platform chemicals and fuels is a promising alternative to conventional fermentation techniques. It is an efficient and economical way to produce chemicals and fuels. Metal-based composites are efficient catalysts due to enhanced surface-active sites. In this study, lead (Pb)-modified bimetallic oxide heterogeneous catalysts Pb/W-ZnO, PbO/Y₂O₃, and PbO/γ-Al₂O₃ were prepared by the wet impregnation method for the direct transformation of sugarcane bagasse cellulose into lactic acid. Cellulose was extracted from sugarcane bagasse using an autoclave-assisted sequential (alkali and acidic) pretreatment. The prepared catalysts, cellulose, and lactic acid were characterized. The concentration of acidic sites of Pb/W-ZnO, PbO/Y₂O₃, and PbO/γ-Al₂O₃ was found to be 3.0, 1.1, and 0.9 mmol/g, respectively. The optimum yield of cellulose was achieved at 62%. Chemocatalytic transformation of extracted cellulose was performed using a Teflon-lined autoclave at 245 °C. The maximum yield of 57.8% lactic acid from sugarcane bagasse cellulose was achieved using Pb/W-ZnO. Lactic acid was not detected when PbO/Y₂O₃ and PbO/γ-Al₂O₃ catalysts were used. This confirms that the enhanced acidic sites of Pb/W-ZnO catalyzed the direct transformation of cellulose into lactic acid. The heterogeneous Pb/W-ZnO catalyst efficiently transformed sugarcane bagasse-derived cellulose into lactic acid, proving to be a facile, efficient, and cost-effective catalyst for lactic acid production.

Electrochemical reduction of 4-nitropyridine-N-oxide (1) is a promising method for synthesising nitrogen-containing compounds, particularly those with pharmaceutical and fine chemical applications. The process can be finely tuned to produce various products, depending on the electrochemical conditions and the specific reagents used. Consequently, in this study the electrochemical reduction of 4-nitropyridine-N-oxide (1) in a buffered acetonitrile solution using carbon electrodes in a simple undivided cell has been investigated and leaded to the formation of several interesting products. The findings indicated, the electroreduction of 4-nitropyridine-N-oxide forms an unstable intermediate that is converted to 4,4'-(1-oxido diazene-1,2-diyl)bis(pyridine N-oxide) (P1) via a paired electrosynthesis process. Also, α and J₀ were evaluated as essential kinetic parameters associated with the irreversible cathodic electron-transfer process of 4-nitropyridine N-oxide (1). Additionally, the reduction of 1 in the presence of aryl sulfinic acid derivatives results in the synthesis of novel sulfonamides, (4-methylphenyl) sulfonamido)pyridine N-oxide (P2) and 4-(phenyl sulfonamide)pyridine N-oxide (P3). The structure of synthesized compounds was confirmed using ¹HNMR, ¹³CNMR, MS, and infrared (IR) spectroscopy.

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Copolymers were synthesized via aqueous chemical oxidative polymerization using aniline (An) and diphenylamine (DPA) as monomers. These copolymers were doped in an acidic medium using hydrochloric acid (HCl) and ammonium persulfate (APS) as the initiators. Multiple analytical techniques characterized the synthesized copolymers, including UV-visible (UV-Vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM) for morphological analysis. Absorption peaks at 357 and 602 nm confirmed π–π* and n–π* transitions, contributing to conjugation within the polymer backbone. The XRD patterns indicated the amorphous nature of the copolymers, while the FTIR spectra revealed the presence of quinoid and benzenoid rings. SEM imaging revealed a layered structure with smooth surfaces, agglomerated particles, and one-dimensional fiber-like or tubular growth. The thermal degradation behavior was examined using thermogravimetric (TG) analysis. The copolymers were soluble in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) but insoluble in water and partially soluble in ethanol. The electrical properties confirmed the semiconductor characteristics, with conductivities in the range of 10^− 4 Scm^− 1. The conductivity of HCl-doped poly(An-co-DPA) shifted when exposed to ammonia, enabling the detection of the ammonia concentration. The copolymers demonstrated good thermal sensing properties at temperatures up to 55 °C. Improvements in the sensor performance are expected through refined sensor design, including optimized polyaniline morphology, adjusted doping levels, and fine-tuned operational conditions. These improvements are expected to enhance the effectiveness of the sensors for various applications.

A new Schiff base, “ethyl 4-((4-hydroxybenzylidene)amino)benzoate” (EHAB) has been synthesized by condensing ethyl-4-aminobenzoate with 4-hydroxybenzaldehyde using ethanol. The synthesized Schiff base was characterized using various analytical techniques, including elemental (C, H, and N) analysis, UV–Visible spectroscopy, FT-IR, multinuclear (¹H and ¹³C) NMR, and TGA/DSC measurements. The Schiff base was further investigated for its DNA-binding affinity. The results indicate that the entitled compound has a moderate binding constant value and binds through an intercalation mode. Computational studies were performed using density functional theory at the B3LYP//def2-TZVP level to investigate structural properties, molecular electrostatic potential (MEP) maps, and infrared and UV-Visible absorption properties. Additionally, the binding of the Schiff base with DNA was evaluated through molecular docking studies, which yielded a binding score of – 6.68 kcal/mol.

This study reports the development of a 1,5-diphenylcarbazide (DPC)-functionalized starch thin film as a colorimetric sensor for chromium (VI) detection via naked-eye detection and /or UV–Vis spectrophotometer. This sensor was fabricated using a starch film as a solid support, in which DPC was embedded as a reagent. It acted as a colorimetric substrate, resulting in the formation of a pinkish-red hue in acidic conditions. The surface morphology of the colorimetric sensor was assessed using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscope (FE-SEM), and energy-dispersive X-ray (EDX) spectroscopy analytical methods. To obtain the highest extraction recovery and reliability, some of the main parameters were optimized. The film was used in conjunction with a spectrophotometer or naked eye, providing a linear range in the range of 0.15-10 mg L^− 1, with determination coefficient R² = 0.9906. The limit of detection and quantification were calculated to be 0.05 and 0.15 mg L^− 1, respectively. The obtained film was successfully applied to the identification and determination of chromium in leather samples with good recoveries.

Antibiotics are among the most prevalent drug pollutants found in water and wastewater. Adsorption is a physical process used to remove antibiotics and transfer them without degrading them from one phase to another. This study investigated the adsorption behavior of the imipenem antibiotic molecule as an aqueous pollutant on graphene-based adsorbents using molecular dynamics (MD) simulation. For this objective, graphene oxide (GO) and reduced graphene oxide (rGO) were considered as adsorbent. In addition, the effect of pH on antibiotic adsorption was investigated. In all simulations, water was utilized as the solvent, and solutions with pH values of 0.1, 2, 7, 12, and 13.9 were generated. According to simulation studies, the ideal pH for imipenem adsorption was 7. All simulations were conducted at 25 ° C and 1 atm of pressure. In a vacuum, simulations were conducted to determine the distance between the centers of mass (COM) of imipenem-GO and imipenem-rGO, which was calculated to be 7.6 (Å) and 5.7 (Å), respectively. Radial distribution function (RDF) curves revealed that the carboxyl functional group plays a key role in the adsorption process and that electrostatic forces were the main force between imipenem molecules and both adsorbent sheets. In addition, GO absorbed imipenem more efficiently than rGO due to its better dispersion in water.