γ-Fe2O3 nanoparticle in NaY-zeolite matrix: Preparation, characterization, and heterogeneous catalytic epoxidation of olefins

Recent advances in catalytic and non-catalytic epoxidation of terpenes: a pathway to bio-based polymers from waste biomass

Epoxides derived from waste biomass are a promising avenue for the production of bio-based polymers, including polyamides, polyesters, polyurethanes, and polycarbonates. This review article explores recent efforts to develop both catalytic and non-catalytic processes for the epoxidation of terpene, employing a variety of oxidizing agents and techniques for process intensification. Experimental investigations into the epoxidation of limonene have shown that these methods can be extended to other terpenes. To optimize the epoxidation of bio-based terpene, there is a need to develop continuous processes that address limitations in mass and heat transfer. This review discusses flow chemistry and innovative reactor designs as part of a multi-scale approach aimed at industrial transformation. These methods facilitate continuous processing, improve mixing, and either eliminate or reduce the need for solvents by enhancing heat transfer capabilities. Overall, the objective of this review is to contribute to the development of commercially viable processes for producing bio-based epoxides from waste biomass.

Insights into the effect of oxygen vacancies on the epoxidation of 1-hexene with hydrogen peroxide over WO3−x/SBA-15

The introduction of oxygen vacancies improved 1-hexene epoxidation performance over WO3−x/SBA-15 catalysts, which is attributed to the enhanced Lewis acidity of the active centers and the reduced energy barrier of the rate-determining step.

Removal of the commercial reactive dye Procion Blue MX-7RX from real textile wastewater using the synthesized Fe2O3 nanoparticles at different particle sizes as a source of Fenton's reagent

The aim of the present study was to signify the role of the particle size of an iron source in the photo-Fenton system for textile dyeing wastewater oxidation. In this respect, a facile synthesis of Fe2O3 nanoparticles (Fe2O3 NPs) via a simple sol-gel route using FeCl3 with different molarities was investigated. The XRD patterns confirmed the formation of Fe2O3 nanoparticles. Furthermore, different molar concentrations of the FeCl3 precursor significantly influenced the size and shape of the nanoparticles. The treatment of wastewater effluents containing the reactive dye Procion Blue MX-7RX from a real textile dyeing facility, was investigated using the synthesized Fe2O3 NPs as a source of the Fenton's reagent photocatalyst. The reaction was initiated and enhanced using an artificial UV source for increasing the ˙OH radical yield. System parameters such as the initial dye load in wastewater, H2O2 and Fe2O3 NP concentrations, pH and the working temperature were investigated for process optimization. The quality of water in this investigation was examined by making measurements of chemical oxygen demand (COD), total suspended solids (TSS) and dye removal which decreased during the illumination time. The effects of different Fe2O3 NPs based on the varying precursor solution molarities namely F1, F3, F5 and F7 on the wastewater remediation were investigated, and the optimum Fe2O3 NPs were found to be F1, which exhibited the highest dye removal value of 83% and a chemical oxygen demand (COD) reduction of 88%. Furthermore, the oxidation kinetics of the Procion Blue dye were studied, and the data were well fitted with the second order kinetics. Finally, the thermodynamic parameters including the changes in the Gibbs free energy of activation, entropy of activation and enthalpy of activation for the Procion Blue oxidation with different Fenton's reagent sources under ultraviolet light illustrated that the reaction was non-spontaneous and endothermic.

Lactobacillus brevis Lipase: Purification, Immobilization onto Magnetic Florosil NPs, Characterization and Application as a Detergent Additive

In this study, a thermo-tolerant and alkaline lipase enzyme was purified from Lactobacillus brevis and immobilized onto modified γ-Fe3O4 florisil nanoparticles (γ-Fe3O4 MF NFs) and the usability of free lipase (FL) and immobilized lipases (IML) as detergent additives was investigated. Lipase enzyme was purified by fractional precipitation using 20% ammonium sulfate, DEAE-Sephadex ion-exchange chromatographic column, and Sephacryl S200 gel filtration chromatographic techniques. Then, the enzyme was purified, which resulted in 135.2-fold purification. Its molecular mass was determined to be 57 kDa by SDS-PAGE. The covalent immobilization of purified lipase was done using γ-Fe3O4 MF NPs. γ-Fe3O4 MF NPs and IML were characterized by using SEM, TEM, FT-IR, and XRD. IML showed a good thermo-stability and its activities were calculated as 80% at 60°C. The free and IML enzymes were most stable at alkaline pHs in the range of 7.0–10.0. Also, IML is more stable towards metal ions compared to free lipase enzyme. Washing performances of some detergent formulations were investigated in the presence and absence of Lipase. Olive oil was removed by the detergent alone and by the detergent and IML at ratios of 45% and 72%, respectively. The study on removal of oil stain from cotton cloths indicated that the removal of oil was superior in the presence of IML and IML with detergent, when compared to the detergent alone.

Syntheses and catalytic activities of new metallodendritic catalysts

Metallodendritic catalysts showed high selectivity in the epoxidation of olefins even after being used for at least five cycles.

Evolution of iron species for promoting the catalytic performance of FeZSM-5 in phenol oxidation

Facile modification of FeZSM-5 utilizing an organic directing agent (ODA) for iron species evolution toward better Fenton activity was developed.

Magnetic self-assembled zeolite clusters for sensitive detection and rapid removal of mercury(II)

We reported here the fabrication of a hierarchical mesoporous zeolite nanocomposite using 20 nm crystalline domins of zeolite L as building "bricks" by a simple and general one-step synthetic approach. By taking advantages of the large pore volumes, superparamagnetic iron oxide nanocrystals could be encapsulated into the nanocomposite conveniently for further facilitate separation and detection. In addition, by covalent coupling of fluorescent receptor (rhodamine-hydrazine), the combination of well-defined inorganic nanomaterials and organic receptors could be applied to selective detection of Hg(2+). Importantly, the unique adsorption capacity enabled by the hierarchical mesoporous zeolite and the efficient removal ability form complex multiphase systems by the magnetic characteristic made this multifunctional nanomaterial an excellent probe for detection, adsorption, and removal of Hg(2+) from waste aqueous solution.