Effect of Different Zeolite Supports on the Catalytic Behavior of Platinum Nanoparticles in Cyclohexene Hydrogenation Reaction

In this study, 1 wt% platinum (Pt) nanoparticles were incorporated into five types of zeolites (HY, Beta, mordenite, ZSM-5, and ferrierite) with an impregnation technique. The synthesis strategy included the use of water as a solvent for the applied Pt source. Moreover, the incorporation process was performed at ambient conditions followed by calcination at 450 °C. The five prepared materials were characterized by different physical and chemical characterization techniques and the obtained results confirmed the formation of Pt nanoparticles with an average size of 5–10 nm. The catalytic performance of the prepared materials was evaluated in the hydrogenation of cyclohexene under a solvent-free system at room temperature. Pt nanoparticles supported on ZSM-5 zeolite exhibited the best catalytic performance. Moreover, the optimization of operational conditions such as temperature, pressure, and catalyst amount was investigated and the obtained results showed the possibility to convert 100% of cyclohexene within 35 min over Pt-ZSM-5. Finally, the reusability of the Pt-ZSM-5 catalyst was investigated in four consecutive runs without treatment and the obtained results showed a negligible activity loss

Effect of Different Zeolite Supports on the Catalytic Behavior of Platinum Nanoparticles in Cyclohexene Hydrogenation Reaction

In this study, 1 wt% platinum (Pt) nanoparticles were incorporated into five types of zeolites (HY, Beta, mordenite, ZSM-5, and ferrierite) with an impregnation technique. The synthesis strategy included the use of water as a solvent for the applied Pt source. Moreover, the incorporation process was performed at ambient conditions followed by calcination at 450 °C. The five prepared materials were characterized by different physical and chemical characterization techniques and the obtained results confirmed the formation of Pt nanoparticles with an average size of 5–10 nm. The catalytic performance of the prepared materials was evaluated in the hydrogenation of cyclohexene under a solvent-free system at room temperature. Pt nanoparticles supported on ZSM-5 zeolite exhibited the best catalytic performance. Moreover, the optimization of operational conditions such as temperature, pressure, and catalyst amount was investigated and the obtained results showed the possibility to convert 100% of cyclohexene within 35 min over Pt-ZSM-5. Finally, the reusability of the Pt-ZSM-5 catalyst was investigated in four consecutive runs without treatment and the obtained results showed a negligible activity loss

Facile synthesis of NiMn2O4/ZnMn2O4 heterostructure nanocomposite for visible-light-driven degradation of methylene blue dye

Nowadays, waste discharge and contaminants in drinking water have emerged as a significant global problem. Therefore, it is necessary to remove these pollutants from the water and photocatalysis is the best technique for this purpose. The co-precipitation technique was employed to produce NiMn2O4 and ZnMn2O4 and a photocatalyst containing NiMn2O4/ZnMn2O4 heterostructure nanocomposite. Various analytical techniques have been ascribed to examine the physical, morphological and optical features of the fabricated catalysts. XRD diffraction peak patterns were utilized to confirm the presence of cubic NiMn2O4, tetragonal ZnMn2O4 and NiMn2O4/ZnMn2O4 phases in a nanocomposite. In photodegradation tests, the nanocomposite catalyst outperformed the individual catalysts. After 60 minutes of visible light exposure, this nanocomposite catalyst eliminated the methylene blue (MB) dye, attaining substantially higher degradation rates than pure NiMn2O4 (66%) and ZnMn2O4 (77%). The nanocomposite catalyst was highly effective against methylene blue (MB) dye with a degradation efficiency of 92%

Valorization of Rice Husk and Straw Agriculture Wastes of Eastern Saudi Arabia: Production of Bio-Based Silica, Lignocellulose, and Activated Carbon

Bio-based silica, lignocellulose, and activated carbon were simply produced via the recycling of Hassawi rice biomass waste of Al-Ahsa governorate in the eastern Saudi Arabia region using a fast chemical treatment procedure. Rice husk and rice straw wastes were collected, ground, and chemically treated with sodium hydroxide to extract silica/silicate from the dried plant tissues. The liquid extract is then treated with acid solutions in order to precipitate silica/silicate at neutral medium. Lowering the pH of the supernatant to 2 resulted in the precipitation of lignocellulose. Thermal treatment of the biomass residue under N2 gas stream resulted in activated carbon production. Separated products were dried/treated and characterized using several physical examination techniques, such as FT-IR, SEM/EDX, XRD, and Raman spectroscopy in order to study their structure and morphology. Silica and lignocelluloses products were then preliminarily used in the treatment of wastewaters and water-desalination processes

Bioactivities of Novel Metal Complexes Involving B Vitamins and Glycine

In this work twelve novel mixed ligand complexes were synthesized. The complexes were formed between a metal ion (Cu(II), Cd(II), Mn(II), Fe(III), Ni(II), Pb(II)) and vitamins (B 3 and B 9) as primary ligands, and glycine as secondary ligand. Melting points, conductivities, and magnetic susceptibilities of the synthesized complexes were determined and the complexes were subjected to elemental analyses. The presence of coordination water molecules in the complex was also supported by TG/DTG thermal analysis. Full elucidation of the molecular structures for the synthesized mixed ligand complexes were confirmed using detailed spectroscopic IR, 1H-, 13C-NMR, and XRD techniques. In addition, cytotoxic and antioxidant activities of the twelve synthesized solid complexes were tested to evaluate their bioactivities

Platinum and vanadate Bioactive Complexes of Glycoside Naringin and Phenolates

Platinum(II) and vanadium(V) solid binary and ternary complexes involving naringin, a flavanone glycoside in found in grapefruit, and some phenolic acids were synthesized and fully characterized using detailed structural and spectroscopic analysis techniques such as IR, NMR, and SEM techniques. The magnetic susceptibility results as well line drawings of the platinum and vanadium complexes showed four-coordinate square-planar and remarkable low-spin diamagnetic species; which is in agreement with the structures proposed. The cytotoxic activities of the binary and ternary vanadium and platinum metal complexes of phenolic acids and naringin were tested and evaluated against HepG2 (human hepatocellular carcinoma), MCF-7 (human breast adenocarcinoma), and HCT116 (human colorectal carcinoma) tumor cell lines. Also, their antioxidant activities were examined by free radical scavenging assay. The relationship between the chemical structure of the synthesized complexes and their biological influence was studied and evaluated