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Metal–organic frameworks (MOFs) have attracted considerable attention for selective deep removal of refractory sulfur compounds from fuels. In this work, cobalt-based MOFs (nanocrystals of Co-ZIF-6...

A successful immobilization of 1-octyl-3-methylimidazolium tetrachloroferrates ([Omim][FeCl4]) thin films on a silica gel while remaining its mesoporousity, was accomplished in this work. The developed catalyst was highly active and cost-effective for deep oxidative desulfurization of refractory thiophenic compounds at room temperature utilizing H2O2 oxidation agent. The reaction products were well separated from fuel by the catalyst itself under a beneficial solvent-free condition. The catalyst was characterized applying different analyses of FT-IR, TGA, XRD, SEM, EDS, AFM, N2 adsorption desorption, BET, and BJH. A sufficiently large pore diameter (∼6.2 nm) and high surface area (∼490 m2/g) of the silica gel for supporting the Lewis acidic [Omim][FeCl4] having a proper anion and cation structure, synergistically enabled a high efficient and selective catalyst for removal of refractory thiophenes. The influences of reaction temperature and time, loading amount of ionic liquid (IL), catalyst and oxidant amount as crucial reaction factors were evaluated in order to have a maximum desulfurization yield. Impressively, only a very low IL loading of 5 wt.% on the silica gel support achieved complete elimination of dibenzothiophene at the optimal mild conditions and room temperature. In the presence of a non-sulfur aromatic hydrocarbon beside different thiophenic models, the desulfurization selectivity of [Omim][FeCl4] increased from 0.92 to 0.95 via immobilization on the silica gel support. A significant decline in the IL consumption was verified as another beneficial effect of this immobilization. The catalyst could be easily separated having a capability for 100 % removal of dibenzothiophene after recycling four times. Meanwhile, GC–MS analysis was employed for further founding of the desulfurization pathway.

In this work, deep extractive catalytic oxidative desulfurization (ODS) of hydrotreated real diesel fuel was attained using a synthesized catalyst of supported molybdenum oxide on mesoporous silica...

A hydrogen-selective and hydrothermally stable membrane composed of silica-zirconia layer deposited on a modified alumina sub layer was successfully prepared. The composite membrane was used for hydrogen purification from synthesis gas in steam methane reforming process. Silica-zirconia layer was synthesized using the CVD method at 923K and atmospheric pressure while the alumina base layer was prepared via sol-gel procedure. DLS, XRD, SEM/EDX, and BET characterization techniques were used to prove that γ-alumina base and silica-zirconia layer are fabricated successfully. Using the composite membrane, hydrogen selectivity toward other gases has improved significantly. Moreover, H2/CH4, H2/CO, and H2/CO2 selectivity have been increased from 700, 350 and 70 in 5 h CVD synthesized membrane to 1600, 750 and 570 for 12 h CVD synthesized membrane respectively. The synthesized Silica-Zirconia membrane successfully altered gases permeability tendency order from H2 > CH4 > CO2 > CO to H2 > CO2 > CO > CH4 which leads to better separation of the product from methane feed. Finally, hydrothermal stability test demonstrated that permeability loss in silica-zirconia CVD coated membrane for H2 is 45.7% after 48 h, while for silica CVD coated on the modified alumina approaches 92.5%.

Lewis acidic ionic liquid (IL) of 1-octyl-3-methylimidazolium tetrachloroferrates ([Omim]FeCl4) with an interesting structure, was synthesized and introduced as a highly effective catalyst and also as extractive solvent in oxidative desulfurization (ODS) of model and real diesel fuels with H2O2 oxidant. FT-IR, H-NMR and TG-DSC analysis were used for characterization of the prepared ILs. GC-FID, GC-PFPD and GC–MS measurements were also employed to investigate the ODS yields and mechanism. The adequate structure and acidic properties of [Omim]FeCl4 allowed removal of thiophenic compounds with high efficiency in an extraction and then oxidation process. The effects of the major processing variables on ODS performance of [Omim]FeCl4 were studied in detail. At the optimal conditions of VIL/Voil of 1/10, O/S molar ratio of 5, reaction time of 15 min and room temperature, BT and DBT were totally eliminated, and 4,6-DMDBT was removed by 99% from the model diesel. Moreover, [Omim]FeCl4 was able to desulfurize two real diesel fuels containing 590 and 2573 ppmw of sulfur with the efficiency of 85% and 61.2%, respectively, at a short time of 15 min. The experimental results also showed a remarkable selectivity of 0.919 for elimination of thiophenic compounds in competition with non-sulfur aromatic model of 2-methyl naphthalene. [Omim]FeCl4 exhibited an excellent recyclability with no significant decline in activity after use in 7 reaction cycles. An overall mechanism was also suggested for desulfurization by the proposed system.

Zirconium-modified mesoporous silica (Zr S) was synthesized as a new promising catalyst for the acetylation reaction of glycerol. In the presence of Zr S catalyst, the selectivity to desired products (TAG and DAG) reached 91%, with a complete conversion of glycerol. Moreover, 12-tungstophosphoric acid (H3PW12O40) was immobilized onto Zr S surface, and the effect of acid strength of catalysts on this reaction was investigated by NH3-temperature programmed desorption (NH3-TPD) technique. Synthesized materials were characterized by various analytical techniques: X-ray powder diffraction, scanning electron microscopy, N2 adsorption–desorption, and inductively coupled plasma spectroscopy.

NMP.FeCl 3 (NMP = N-methyl-2-pyrrolidone, C 5 H 9 NO) ionic liquid (IL) was effectively immobilized on γ-Al 2 O 3 as a support and examined in the catalytic oxidative deep desulfurization (ODS) of BT, DBT and 4,6-DMDBT from model oil employing 30 wt.% H 2 O 2 as the oxidant reagent. The supported catalyst was prepared via a simple wet impregnation and the effective immobilization of IL was confirmed by FTIR, SEM, EDS, XRD, BET and BJH analysis. The maximum efficiency of 99% was achieved for ODS of DBT using supported IL at the loading amount of 10 wt.%, H 2 O 2 /sulfur molar ratio of 4, temperature of 40 °C, and duration of 90 min. The use of support material in this study resulted in using a lower amount of IL in ODS process. The ODS reactivity of the thiophenic compounds changed in the order of DBT > 4,6-DMDBT ≫ BT. The catalyst was recycled for several times and showed no significant loss in the activity. Furthermore, based on GC–MS analysis of the products, desulfurization mechanism was surveyed and a reasonable pathway was proposed.

Purpose: Hydroxyurea (HU) is a well-known chemotherapy drug with several side effects which limit its clinical application. This study was conducted to improve its therapeutic efficiency against breast cancer using liposomes as FDA-approved drug carriers. Methods: PEGylated nanoliposomes-containing HU (NL-HU) were made via a thin-film hydration method, and assessed in terms of zeta potential, size, morphology, release, stability, cellular uptake, and cytotoxicity. The particle size and zeta potential of NL-HU were specified by zeta-sizer. The drug release from liposomes was assessed by dialysis diffusion method. Cellular uptake was evaluated by flow cytometry. The cytotoxicity was designated by methyl thiazolyl diphenyl-tetrazolium bromide (MTT) test. Results: The size and zeta value of NL-HU were gotten as 85 nm and -27 mV, respectively. NL-HU were spherical.NL-HU vesicles were detected to be stable for two months. The slow drug release and Weibull kinetic model were obtained. Liposomes considerably enhanced the uptake of HU into BT-474 human breast cancer cells. The cytotoxicity of NL-HU on BT-474 cells was found to be significantly more than that of free HU. Conclusion: The results confirmed these PEGylated nanoliposomes containing drug are potentially suitable against in vitro model of breast cancer.

Cisplatin is a chemotherapeutic agent used for treating various malignancies. The study aimed to prepare pegylated liposomal cisplatin and evaluate its efficacy against human breast cancer cell line MCF-7. Drug-loaded nanoparticles were synthesized by reverse phase evaporation technique. The study is highlighted by extensive characterization of nanoparticles in terms of nanoparticle morphology, type of drug entrapment, cisplatin retention capability, and cytotoxicity effects. The size, size distribution, and zeta potential of nanodrug were estimated 142 nm, 0.33, and -22 mV, respectively. Drug-loading efficiency was equal to 48% that occurred physically. Furthermore, high retention capability (39% of drug was released after 72 h) with significantly enhanced cytotoxicity of nanodrug (1.75 times more than the standard drug) confirmed the potency of liposomal nanoparticles as proper cisplatin carrier.

In this investigation, quantitative structure-property relationship (QSPR) modelling of adsorption coefficients of 69 aromatic compounds on multi-wall carbon nanotubes (MWCNTs) was studied using the Monte Carlo method. QSPR models were calculated with CORAL software, and optimal descriptors were calculated with the simplified molecular input line entry system (SMILES) and hydrogen-suppressed molecular graphs (HSGs). The aromatic compound data set was randomly split into training, invisible training, calibration and validation sets. Analysis of three probes of the Monte Carlo optimization with three random splits was done. The results from three random splits displayed robust, very simple, predictable and reliable models for the training, invisible training, calibration and validation sets with a coefficient of determination (r