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• WEPS was successfully converted to valuable fuel oil. • Developed process significantly reduced the styrene content of liquid oil. • AB-Type/multiphase catalytic process enhanced quality of product oil. • Product oil is suitable for IC engine and generator set applications. Upgraded fuel oil was produced from the waste expanded polystyrene (WEPS) using pyrolysis and in-situ selective aromatization in a specially designed reactor. The catalytic pyrolysis of WEPS was performed keeping the catalyst in three different types of catalyst arrangements inside the reactor i.e., A-type/catalyst in liquid phase, B-type/catalyst in vapour phase, and AB-type or Multiphase/catalyst in both liquid and vapour phases, respectively. The ZSM-5 ammonium powder was used as a catalyst with varying feed to catalyst ratio and 20:1 was found to be optimum. Aromatics of fuel range like benzene, toluene, and ethylbenzene (BTE) were significantly increased and styrene got reduced by many folds when AB-type/multiphase catalytic pyrolysis was performed. The thermal pyrolysis produced maximum liquid yield of 94.37 wt% at a temperature of 650 °C and a heating rate of 15 °C/min. The maximum liquid yield of 88.05 wt%, 78.85 wt%, and 75.11 wt% were obtained for the A-type, B-type, and AB-type catalytic pyrolysis at the temperature of 600 °C, 550 °C and 550 °C, respectively using the same heating rate. The liquid oil of thermal pyrolysis contains very low amount of fuel range aromatics i.e., BTE of 11.38 wt% and the highest amount of styrene (84.74 wt%). In contrarily, BTE content for the catalytic process increased progressively in the order of 18.98 wt% (A-type) < 24.27 wt% (B-type) < 28.12 wt% (AB-type). The styrene content significantly decreased to a very low value of 46.30 wt% for AB-type/multiphase pyrolysis at the temperature of 550 °C. [ABSTRACT FROM AUTHOR]

Efficient NO x removal is an important for controlling air pollution, and developing effective catalysts is a significant challenge. In this study, (M = Co, Cu, Cr, and Mo) M/CeO 2 -MgO catalysts were prepared by the co-precipitation method followed by the wet-impregnation method for NO removal by H 2 -SCR technology. The catalysts were characterized by BET, XRD, XPS, TEM, and H 2 -TPR. The CeO 2 -MgO showed the BET surface area of 78 m2/g, which is slightly decreased after the impregnation of Cu, Co, Cr, and Mo metals. X-ray diffraction showed the presence of cubic phase by CeO 2 and MgO. The Cu/CeO 2 -MgO catalyst shows the highest lattice strain, Ce3+ content, and adsorbed oxygen with values of 0.66%, 30.54%, and 74.12%. A maximum NO x conversion of 78% was achieved over the Cu/CeO 2 -MgO catalyst with a slightly large temperature window (100–250 ℃) among all the catalysts. The catalyst's sequence of NO x conversion was as follows: Cu/CeO 2 -MgO > Mo/CeO 2 -MgO > Co/CeO 2 -MgO > Cr/CeO 2 -MgO > CeO 2 -MgO. The N 2 selectivity followed the same order as NO conversion except for the Cr catalyst, which performed better than the Co impregnated catalyst. [Display omitted] • Use of hydrogen showed the sustainable path toward the NO x reduction. • Hydrogen reductant eliminate the emission of carbon pollutants. • Development of non-noble catalyst for H 2 -SCR application. • Catalysts showed better NO x conversion between 125 and 250 ℃ for H 2 -SCR. • Mo/CeO 2 -MgO catalyst showed 71% NO x reduction with 68% N 2 selectivity for H 2 -SCR application [ABSTRACT FROM AUTHOR]

Due to the limited array of the currently available copper chelators, research of such compounds continues to be of clinical interest. Notably, o -dihydroxycoumarins have been previously shown to be potent iron chelators under neutral conditions. Within this study, the interaction of a series of natural coumarins and their synthetic analogs with copper has been evaluated in order to obtain structure-activity relationships under different pathophysiological pH conditions. Both competitive and non-competitive methods have been employed. Analysis of cupric ion reduction has also been performed. Under mildly competitive conditions, cupric chelation was observed for o -dihydroxycoumarins, and partially for o -diacetoxycoumarin. Non-competitive studies showed that cuprous ions are not chelated at all and that the stoichiometries of the most active 6,7- and 7,8-dihydroxycoumarins to cupric ions ranged from 1:1 to 2:1 depending on pH and concentration. Interestingly, under highly competitive conditions, coumarins were not capable of chelating cupric ions, either. Reduction experiments have shown that 13 out of the 15 coumarins included in this study reduced cupric ions. However, significant differences depending on their structures were apparent in their potencies. O -dihydroxycoumarins were the most potent ones again. Conclusion O -dihydroxycoumarins are moderately active cupric ion chelators with potent copper reducing properties. [ABSTRACT FROM AUTHOR]

Abstract: Herein, an efficient synthetic approach to a furopyrazine scaffold with four points of diversity, starting from 2(1H)-pyrazinones, with dipeptomimetic properties, is presented. R-groups corresponding to amino acid side chains were introduced during the 2(1H)-pyrazinone and subsequent furopyrazine formation. The furopyrazine scaffold was further functionalized with an amino- and a carboxy-terminus resulting in a conformationally restricted dipeptidomimetic scaffold. The carboxy-terminus was introduced via a chemoselective vinylation of the 7-position followed by oxidative cleavage, while the amino-terminus was obtained via Buchwald–Hartwig amidation of the 2-position of the scaffold. The versatility of the synthetic method was demonstrated by the synthesis of a small library of diversely substituted furopyrazines having various amino acid side chains on the four points of diversity. Evaluation with an X-ray structure of the scaffold and computational analysis supports the exploitation of the furopyrazine scaffold as a restricted dipeptide mimic, which can mimic the two central residues of a β-turn. [Copyright &y& Elsevier]

An active composite of nitrogen-doped graphene oxide (N-rGO) supported gadolinium doped bismuth ferrite (BGFO), (BGFO/N-rGO), was synthesized by a modified hydrothermal method. The composite was characterized by X-ray photoelectron spectroscopy (XPS), fourier transform-infrared (FT-IR), diffused reflectance spectroscopy (DRS), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron spectroscopy (TEM), electrical impedance spectroscopy (EIS), photoluminescence (PL) and mott-schottky (M-S) analysis. Doping of Gd in pristine bismuth ferrite suppressed photoinduced electron-hole pair recombination. This resulted in a significant increase in the photocatalytic activity of BGFO (k = 7.89 gcat-1.h-1) in comparison to bare bismuth ferrite (k = 3.15 gcat-1.h-1) on the degradation of RhB. Further, incorporation of N-rGO with BGFO lead to the formation of a heterojunction that provided high surface area and a passage to transfer the electrons from BGFO to N-rGO. This further reduced the electron-hole pair recombination and improved the photocatalytic degradation of rhodamine B by 600% (k = 18.91 gcat-1.h-1) due to the availability of sufficient charge carriers at the surface of the catalyst. Superoxide ion (O 2−•) was found most active radical among the various reactive species viz. hydroxyl ion (OH•), electron (e-), and hole (h+) as confirmed by trapping experiments. A proposed mechanism of the degradation process was elucidated by species trapping experiments. • N-rGO supported BGFO heterojunction was synthesized by hydrothermal method. • Chemical interaction between BGFO and N-rGO was analyzed. • N-rGO support enhanced electron conductivity and charge carrier density significantly. • BGFO/NrGO showed high potential for photocatalytic degration of RhB. • Possible mechanism of RhB degradation was proposed. [ABSTRACT FROM AUTHOR]