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The current study focuses on the synthesis of Cerium oxide (CeO2) nanocatalyst via Tragacanth Gum (TG) using the wet impregnation method and its application for sustainable biodiesel production from a novel, non-edible Descurainia sophia (L.) Webb ex Prantl seed oil. The D. sophia seed oil has higher oil content (36 wt%) and free fatty acid (FFA) value (0.6 mg KOH/g). Innovative analytical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy, were used to characterize the newly synthesized, environmentally friendly, and recyclable CeO2-TG phytonanocatalyst (FT-IR). The results show that the CeO2-TG phytonanocatalyst was 22 nm in diameter with a spherical shape outer morphology, while the inner structure was hexagonal. Due to low FFA content, the D. sophia seed oil was pretreated and transesterified via a single step. Using varying parameters, the optimized process variables were determined via Response Surface Methodology (RSM). The optimum process values were 8:1 methanol to oil molar ratio, 0.3 wt% catalyst concentration, 90 °C temperature, and reaction time of 210 min with 98% biodiesel yield. The recently created phytonanocatalyst was reliable and effective, with three times reusability in the transesterification reaction. Thin layer chromatography (TLC), FT-IR, gas chromatography–mass spectroscopy (GCMS), and Nuclear magnetic resonance (NMR) analyses were used to characterize the synthesized biodiesel. Physico-chemical properties of D. sophia biodiesel, i.e., Kinematic viscosity (4.23 mm2/s), density (0.800 kg/m3), pour point (−7 °C), cloud point (−12 °C), and flash point (73.5 °C) agree well with international biodiesel standards (ASTM-6751, 951), (EU-14214), and China (GB/T 20828) standards. The results show that the synthesized nanocatalyst demonstrated remarkable stability, indicating a bright future for industrial biodiesel production from low-cost feedstock. [ABSTRACT FROM AUTHOR]

Highlights: Brassica juncea (L.) Czern. seeds contain 30% oil content and 0.43 mg KOH/g FFA content. Ni-TG nano-catalyst was synthesized through a wet impregnation route. The Ni-TG nano-catalyst has a crystalline size of 39.29 nm with a semispherical and ovoid shape. 0.3 wt% catalyst concentration, 6:1 methanol to oil ratio at 90 °C for 120 min yielded 93% of Brassica juncea (L.) Czern. biodiesel. In the current study, a novel green nano-catalyst from Tragacanth gum (TG) was synthesized and used for sustainable biodiesel production from Brassica juncea (L.) Czern. seed oil. Brassica juncea (L.) Czern contains 30% oil on dry basis and free fatty acid content of 0.43 mg KOH/g. Physiochemical characterization of a newly synthesized nano-catalyst was performed by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The XRD results showed an average crystalline size of 39.29 nm. TEM analysis showed the cluster form of NiSO4 nanoparticles with a size range from 30–50.5 nm. SEM analysis of the catalyst showed semispherical and ovoid shapes with surface agglomeration. The synthesized catalyst was recovered and re-used in four repeated transesterification cycles. Maximum biodiesel yield (93%) was accomplished at 6:1 methanol to oil molar ratio, catalyst concentration of 0.3 wt%, at 90 °C for 120 min at 600 rpm using Response Surface Methodology (RSM) coupled with central composite design (CCD). Brassica juncea (L.) Czern. biodiesel was characterized by Thin Layer Chromatography (TLC), FT-IR, Nuclear Magnetic Resonance (NMR) (1H, 13C), and Gas Chromatography-Mass Spectroscopy (GCMS) analytical techniques. The major fatty acid methyl esters were 16-Octadecenoic acid and 9-Octadecenoic acid methyl ester. The fuel properties, i.e., flash point (97 °C), density (825 kg/m3 at 40 °C), kinematic viscosity (4.66 mm2/s), pour point (–10 °C), cloud point (–14 °C), sulfur content (66 wt.%), and total acid number (182 mg KOH/g) were according to the International biodiesel standards. The reaction kinetic parameters were determined, and all the reactions followed Pseudo first-order kinetics. It was concluded that non-edible Brassica juncea (L.) Czern. seed oil is one of the sustainable candidates for the future biofuel industry using a cleaner, reusable, and highly active Ni-modified TG nano-catalyst. [ABSTRACT FROM AUTHOR]

Environmental remediation of heavy metals from wastewater is becoming popular area in the field of membrane technology. Heavy metals are toxic in nature and have ability to bioaccumulate in water bodies. In current study, zirconium‐based metal organic frameworks (MOFs), that is, UiO‐66 and UiO‐66‐SO3H with a mean diameter of 200 nm were synthesized and intercalated into polyethersulfone (PES) substrate to fabricate thin‐film nanocomposite (TFN) membranes via an interfacial polymerization (IP) method. TFN membranes exhibit higher selectivity and permeability as compared to thin‐film composite (TFC) membranes for heavy metals, such as cadmium (Cd) and mercury (Hg). Zirconium‐based MOFs are highly stable in water and due to smaller pore size enhanced hydrophilicity of TFN membranes. In addition, TFN membrane with functionalized MOF (UiO‐66‐SO3H) performed best as compared to TFC and TFN with UiO‐66 MOF. The effect of loading of different weight percentages (wt%) of both MOFs for TFN membranes was also investigated. The TFN membranes with loading (0.2 wt%) of UiO‐66‐SO3H displayed highest permeability of 9.57 LMH/bar and notable rejections of 90% and 87.7% toward Cd and Hg, respectively. To our best understanding, it is the first study of intercalating functionalized UiO‐66‐SO3H in TFC membranes by IP and their application on heavy metals especially Cd and Hg. [ABSTRACT FROM AUTHOR]

The study was conducted to highlight a detailed account of morphology of pollen chosen species of Lamiaceae through scanning electron microscopy, and the anatomical characteristics of leaf epidermis of seven species using simple light microscopy. In results, Anisomeles indica and Otostegia aucheri belong to subfamily Lamioideae because it has tricolpate pollen while the rest eight species belong to subfamily Nepetoideae (hexacolpate pollen). The exine sculpturing of pollen of studied species was found to be reticulate. In the family Lamiaceae, four kinds of stomata were found anomocytic, anisocytic, diacytic, and actinocytic, respectively. The cell wall patterns of epidermal cells were irregular or polygonal with straight or undulate walls. It was noted that the variety of the epidermal trichomes seems of taxonomically important for the identification of species of Lamiaceae. Both nonglandular and glandular trichomes were analyzed. The nonglandular trichomes were characterized with long, thin, and pointed apical unicellular cells. The nonglandular trichomes were A-shaped in Thymus linearis. In Perovskia abrotanoides, stellate glandular trichomes were observed whereas in A. indica and Mentha royleana both glandular and nonglandular trichomes were found. In A. indica, the nonglandular trichomes were sessile and peltate in M. royleana. For the first time in this study, pollen and foliar micromorphological features of selected species of this area are carried out. These taxonomic characters were found to be important in discrimination of species from each other. In future, the detailed study with comprehensive morphology coupled with other important characters is required for delimitation of taxa at various levels. [ABSTRACT FROM AUTHOR]

The green macroalgae present in freshwater ecosystems have attracted a great attention of the world scientists for removal of heavy metals from wastewater. In this mesocosm study, the uptake rates of heavy metals such as cadmium (Cd), nickel (Ni), chromium (Cr), and lead (Pb) byOedogonium westi(O. westti) were measured. The equilibrium adsorption capabilities ofO. westtiwere different for Cd, Ni, Cr, and Pb (0.974, 0.418, 0.620, and 0.261 mgg–1, respectively) at 18°C and pH 5.0. Furthermore, the removal efficiencies for Cd, Cr, Ni and Pb were observed from 55–95%, 61–93%, 59–89%, and 61–96%, respectively. The highest removal efficiency was observed for Cd and Cr from aqueous solution at acidic pH and low initial metal concentrations. However, the removal efficiencies of Ni and Pb were higher at high pH and high concentrations of metals in aqueous solution. The results summarized that O. westti is a suitable candidate for removal of selected toxic heavy metals from the aqueous solutions. [ABSTRACT FROM PUBLISHER]

Palladium(II) bromide complexes of thioamides having the general formulae [PdL2Br2] and [PdL4]Br2 where L = Thiourea (Tu), Methylthiourea (Metu), Dimethylthiourea (Dmtu), Tetramethylthiourea (Tmtu), Imidazolidine-2-thione (Imt), Mercaptopyridine (Mpy), Mercaptopyrimidine (Mpm) and Thionicotinamide (Tna) were prepared by reacting K2[PdCl4] with KBr and the corresponding thioamides. The complexes were characterized by elemental analysis, IR and NMR spectroscopy, and one of them, [Pd(Tmtu)4]Br2 ( 1) by X-ray crystallography. The crystal structure of 1 shows a square-planar coordination environment around the Pd(II) atoms with the average cis and trans S–Pd–S bond angles of 90.0° and 180.0°, respectively. The synthesized complexes were screened for antibacterial effects, and the results showed that the complexes exhibit significant activities against both gram positive and gram negative bacteria. [ABSTRACT FROM AUTHOR]

The article reports a two-step synthesis of composite nanofibrous mats of polytetraflouroethylene/zinc oxide (PTFE-ZnO); first, emulsion electrospinning of precursor solution was performed to yield as-spun mats followed by heat treatment at 280 °C. The surface of pure PTFE nanofibrous mats was modified by varying the amount of ZnO loadings in the electrospinning solution from 10 to 20 wt.%. Physiochemical characterization of synthesized mats was performed by FESEM, EDX, AFM, FTIR, Raman, TGA and contact angle goniometry. It was observed that fiber mean diameter decreased from 0.243 ± 15.10 μm to 0.17 ± 30.50 μm, RMS roughness increased from 112 to 627 nm and CA improved from 102.56° to 121.55° with the rise in ZnO content up to 20 wt% compared to the pure PTFE mats. Higher surface area, roughness and hydrophobicity of PTFE-ZnO mats resulted into significantly enhanced adsorption ability of VOCs on their surfaces against three model VOCs, namely, toluene, acetone and formaldehyde. The results have demonstrated that surface adsorption capacity of tested VOCs has considerably increased to 10, 07 and 03 folds respectively for the nanofibrous mats containing 20 wt.% ZnO, compared to pure PTFE mats. Based on these findings, these nanofibrous mats can potentially be used as filters for VOCs and particulate removal from air in the processing industries. [ABSTRACT FROM AUTHOR]

The diminution of edible oils and increasing cost of edible oils and biodiesel have gained the interest of many researchers for non-edible oils as biodiesel feed stock. The major hurdle in the commercialization of biodiesel is the high cost of feedstock. Due to fast mushrooming of fast food centers, waste cooking oil is one of the most economical feedstock available for the biodiesel production. The high free fatty acid contents and moisture in the waste cooking oil hinders the homogenous transesterification for the commercial purposes. Mixed oxides of Cu with Ni and Ce were synthesized by co-precipitation method and their efficacy for the production of biodiesel from the waste cooking oil was inspected. The acid catalyzed heterogeneous transesterification of waste cooking oil was performed in the sealed container. It was also interesting to mention that no pre-treatment was executed for the waste cooking oil conversion to biodiesel. It was investigated that mixed oxide catalyst CuO-CeO2 proved to be the potential candidate in pilot scale biodiesel production from waste cooking oil having about 92% conversion rate. Comprehensive chemical analysis of biodiesel including NMR, GC-MS, and FT-IR supports our result. [ABSTRACT FROM AUTHOR]