Vol. 3 No. 3 (2025): November

One of the most significant areas of nanotechnology is carbon nanotubes. Because of their special properties and cylindrical structure, carbon nanotubes are employed in nanotechnology applications. Their many qualities, such as stiffness, strength, and surface area, have generated interest in the pharmaceutical industry. Single-walled nanotubes and multiple-walled nanotubes are the two types of CNTs. There are several techniques for creating CNTs, including chemical deposition, laser ablation, and arc discharge. These nanotubes are employed in drug delivery and diagnostic systems. Because of its many applications in medicine delivery, it is critical to understand the toxicities of carbon nanotubes and how to handle any problems that may arise. Many research have lately focused on the mechanism of carbon nanotube biodegradation. Single and double walled carbon nanotubes must be a safer and more effective way to distribute medications.

This investigation presents the synthesis and comparative assessment of three magnetite-based composite adsorbents, including Magnetite Humic Acid (MA), Magnetite Activated Charcoal (MB), and Magnetite Lignin (MC), aimed to remove Procion Red (PR) from aqueous solutions. The characterization of the materials was conducted through XRD, BET, and FTIR analyses, which validated the successful synthesis of magnetite and its interactions with the respective organic components. The point of zero charge (pHpzc) values obtained were 4.75, 5.09, and 4.10 for MA, MB, and MC, respectively. Adsorption experiments were performed under these pHpzc conditions to mitigate electrostatic influences. Kinetic investigations demonstrated that the adsorption process adhered to a pseudo-second-order model, signifying that chemisorption was the prevailing mechanism. Furthermore, the Langmuir isotherm yielded the most accurate representation of the equilibrium data, implying the occurrence of monolayer adsorption. MB demonstrated the highest adsorption capacity of PR, recorded at 52.632 mg/g at a temperature of 50^oC. This observation underscores the benefits associated with its elevated surface area and the effective dispersion of Fe₃O₄ particles within the activated carbon matrix. The comparative analysis elucidates the impact of organic matrix selection on surface characteristics, interaction dynamics, and the overall efficacy of adsorption processes. This study presents novel findings regarding the development of natural carbon-magnetite composites aimed at enhancing the efficiency of dye removal processes.

The catalytic oxidation of cyclohexanone using environmentally benign oxidants remains a key challenge in sustainable organic synthesis. In this study, natural zeolite (clinoptilolite and mordenite) and bentonite were evaluated as heterogeneous catalysts for the oxidation of cyclohexanone with hydrogen peroxide under reflux at 90 °C. Structural characterization by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) confirmed the aluminosilicate frameworks, where clinoptilolite exhibited the highest crystallinity, followed by bentonite and mordenite. The oxidation products were analyzed using FTIR, melting point measurements, and gas chromatography–mass spectrometry (GC–MS). Despite the catalytic activity of all materials, FTIR and melting point analyses revealed that the expected adipic acid was not formed under the applied conditions. GC–MS results indicated the formation of partially oxidized oxygenated intermediates such as alcohols, ethers, and carbonyl derivatives, whose distribution strongly depended on the catalyst’s pore structure and surface properties. Clinoptilolite promoted confined partial oxidation due to its microporous structure, whereas bentonite facilitated non-selective oxidation owing to its open layered framework. These findings emphasize that the interplay between molecular confinement and oxygen accessibility governs the selectivity of cyclohexanone oxidation and provides insights for the rational design of improved zeolite- and clay-based catalytic systems for green oxidation reactions.

The synthesis of adipic acid through the oxidation of a cyclohexanone–cyclohexanol mixture was investigated using 30% hydrogen peroxide (H₂O₂) as the oxidizing agent and a B₂O₃–SiO₂ catalyst synthesized via heat treatment at various temperatures. This study aimed to evaluate the catalytic performance of B₂O₃–SiO₂ in facilitating the oxidation reaction and to determine the optimum reaction conditions for achieving the maximum yield of adipic acid. The effects of reaction time and temperature on the oxidation process were systematically studied. The reactions were conducted for 5, 6, 7, and 8 hours at temperatures of 60°C, 70°C, 80°C, and 90°C. The reaction products were analyzed using Gas Chromatography (GC) and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that the B₂O₃–SiO₂ catalyst exhibited the highest catalytic activity at 90°C, producing adipic acid with a maximum yield of 2.36% after 7 hours of reaction. Based on FT-IR characterization, it was observed that the B₂O₃–SiO₂ catalyst became unstable after the reaction, as indicated by the reduction of Brønsted acid sites. This decrease in acidity led to a less effective catalytic performance, resulting in a suboptimal oxidation process and a relatively low yield of adipic acid.

Norfloxacin (NFX) and moxifloxacin (MFX) are widely used fluoroquinolone antibiotics that are frequently detected as residues in aquatic environments. Their persistent presence can increase the risk of antibiotic-resistant bacteria (ARB) emerging, making the selective removal of these compounds from water systems essential. This study evaluates the adsorption selectivity of NFX and MFX using graphene oxide (GO) as a potential adsorbent. The results show that GO exhibits a higher affinity for NFX than for MFX, indicating selective interactions between the functional groups of GO and NFX molecules. These findings confirm the potential of GO as a selective adsorbent for the removal of specific antibiotics from aqueous solutions and provide a basis for developing more effective wastewater treatment strategies.