ABSTRACT
The copper/nickel-metal on commercial H-Beta zeolite supports was synthesized with different wt % (Ni) of 5, 10, 15, and 20, and was used in the cyclohexene epoxidation process. The synthesized catalyst has been used in a continuous reactor for the cyclohexene epoxidation process, with mild conditions and H2O2 as an oxidant. The catalytic performance was ascertained by adjusting parameters such as the temperature, pressure, WHSV, reaction time, and solvents. The catalytic performance showed the resulting yield in both cyclohexene conversion and selectivity was more than 98.5%. The catalyst's textural attributes, morphology, chemical composition, and stability were determined using FT-IR, XRD, BET, HR-SEM, and TPD. The most active catalyst among those that were synthesized was evaluated, and the reaction parameters were selected to optimize yield and conversion. The H-Beta/Cu/Ni (15%) catalyst has the best conversion (98.5%) and selectivity (100%) for cyclohexene among the catalysts examined. Cu and Ni(15%) metals were successfully added to the H-Beta zeolite, causing little damage to the crystalline structure and resulting in good reusability over five cycles, as well as little loss of catalytic selectivity. Acetonitrile was the solvent that provided the highest conversion and selectivity among the others. These findings show that H-Beta/Cu/Ni bimetallic catalysts have the potential to be effective epoxidation catalysts. Because of their outstanding conversion and selectivity, the continuous reaction technique used in this work makes them appropriate for industrial production-level applications.
ABSTRACT
This work examines the hydrodeoxygenation (HDO) activity of non-edible oils using a high surface area catalyst. The HDO activity was thoroughly examined and contrasted using the high surface area catalyst Ni/Pt-ZSM-5 as well as other supports like MCM-48 and H-beta. Ni/Pt bimetals supported on mesoporous ZSM-5 were created via reverse order impregnation to facilitate HDO of non-edible oils. Techniques such as XRD, FT-IR, BET, HR-TEM, HR-SEM, TPD, and TGA were used to characterize the produced catalysts. The synthesized catalysts considerably influenced the hydrodeoxygenation activities for the synthesis of lengthy chain hydrocarbons in a stainless-steel reactor with a high-pressure fixed bed between 300 and 375 °C under 10-40 bar hydrogen pressure. High levels of Ni/Pt-ZSM-5 acidity, textural, and H2 consumption qualities were discovered. Distributions of the products were also reviewed, along with comparisons of the structure-activity connections.
ABSTRACT
A wetness impregnation method was used to impregnate the substrate with a substantial quantity of oleic acid together with a metal precursor, leading to significantly dispersed Ni-Fe bimetallic catalysts based on mesoporous SBA-15. Using a wide variety of characterization methods, such as XRD, BET, and TEM Analysis, the physiochemical properties of the catalyst were determined. The addition of the metal does not have any effect on the structural characteristics of the SBA-15 catalyst, as validated by transmission electron microscopy (TEM), which shows that the prepared SBA-15 supported catalyst has a hexagonal mesoporous structure. The catalytic capabilities of the Ni-Fe-SBA-15 catalysts were evaluated in the conversion of BzOH using tert-butyl hydroperoxide (TBHP) as an oxidant and acetonitrile as a solvent. The Ni/Fe-SBA-15 (NFS-15) catalytic composition is the best of the developed catalysts, with a maximum conversion of 98% and a selectivity of 99%. In-depth investigations were conducted into the molar ratio of TBHP to BzOH, the dosage of the catalyst, the reaction rate, temperature, and solvent. The recycling investigations indicate that the synthesized Ni/Fe-SBA-15 (NFS-15) catalyst seems to be more durable up to seven successive cycles.
ABSTRACT
Isomerization is extensively utilized in the petroleum industry, and this study demonstrates an energy-efficient process utilizing an ionic liquid catalyst. 1-Ethyl-3-methylimidazolium triflate [Emim][TFO] as an ionic liquid was immobilized on solid support Fe/SBA-15. Variants of the catalyst were developed with the Fe constant at 5% and different ratios of ionic liquid. In the catalyst Fe/[Emim][TFO]/SBA-15, the metal Fe was loaded via the impregnation method, and subsequently, the ionic liquid variants Fe/[Emim][TFO](10)/SBA-15, Fe/[Emim][TFO](20)/SBA-15, and Fe/[Emim][TFO](30)/SBA-15 were synthesized. The physical properties of the synthesized catalyst were studied using standard characteristic techniques. The process performance was studied for variants of each parameter, which include temperature, hydrogen flow rate, pressure, and weight hourly space velocity. The iso-products of n-heptane and n-octane were obtained with an appreciable conversion of >90% and a selectivity of >95% with the catalyst Fe/[Emim][TFO](20)/SBA-15 among the other synthesized catalysts. The process yielded a high quantum of iso-products with negligible cracked products at a low temperature of 140 °C. The catalyst Fe/[Emim][TFO](20)/SBA-15 at 140 °C delivered the highest yield of iso-alkanes among the three catalysts. Iso-alkanes are instrumental tools for increasing the octane number of a fuel. This study delivers high iso-alkane content fuel, which can provide the best anti knock capability and enhance fuel efficiency for the life of modern high-powered engines. The results demonstrate a process that is energy-efficient, economic, and environmentally friendly.
ABSTRACT
In the present study, we have improvised a biogenic method to fabricate zinc oxide nanoparticles (ZnO NPs) using chitosan and an aqueous extract of the leaves of Elsholtzia blanda. Characterization of the fabricated products was carried out with the help of ultraviolet-visible, Fourier transform infrared, X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray analyses. The size of the improvised ZnO NP measured between 20 and 70 nm and had a spherical and hexagonal shape. The ZnO NPs proved to be highly effective in the antidiabetic test as the sample showed the highest percentage of enzyme inhibition at 74% ± 3.7, while in the antioxidant test, 78% was the maximum percentage of 2,2-diphenyl-1-picrylhydrazyl hydrate scavenging activity. The cytotoxic effect was investigated against the human osteosarcoma (MG-63) cell line, and the IC50 value was 62.61 µg/mL. Photocatalytic efficiency was studied by the degradation of Congo red where 91% of dye degradation was observed. From the various analyses, it can be concluded that the as-synthesized NPs may be suitable for various biomedical applications as well as for environmental remediation.
ABSTRACT
Fluorescence spectral techniques aided by molecular docking (Mol.Doc) approach were employed in probing the molecular interactions existing between D-glucose and resorcinol based acridinedione (ADR) dyes. ADR dyes has been classified into PET and non-PET dyes based on the substitution in the 9th position of acridinedione ring structure. Addition of glucose to PET dye (ADR1) resulted in a decrease in the absorbance whereas to that of ADR2 dye (non-PET character in aqueous medium) resulted in a significant increase in the absorbance. The formation of an isosbestic point reveals the existence of a ground state interaction existing between the dye and sugar molecule. Addition of glucose to PET dye resulted in a drastic increase in the fluorescent enhancement (FE) and subsequent addition resulted in a marked decrease in the fluorescent intensity with no apparent shift of emission maximum. Interestingly, neither characteristic shift nor variation in emission intensity was observed in the case of ADR2 dye. Fluorescence lifetime studies of ADR1 dye in the presence of glucose illustrate the existence of multiple distinguishable micro environments of dye. Mol.Doc studies authenticate the co-existence of hydrogen bonding (HB) and hydrophobic interaction wherein the dye and sugar molecule acts as HB donor and acceptor resulting in a stable conformer. These conformers are governed predominantly by HB interactions. The nature of interaction of a simple sugar with ADR dyes are explored in depth by fluorescent techniques in coordination with docking studies is imparted in the present study.
