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The manganese carbonate catalyst, prepared by precipitation method, was used in transesterification of soybean oil under subcritical condition of methanol. Catalyst samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The triacylglycerol (TAG) conversion and fatty acid methyl esters (FAME) yield were determined using high performance liquid chromatography (HPLC). The transesterification was realized for 1 h using various working conditions: 0-3 wt.% of catalyst (based on the mass of oil), the mole ratio of methanol to oil from 13:1 to 27:1 and temperature ranging from 393 to 473 K. A maximum TAG conversion of 98.1% could be obtained at the optimal reaction conditions: 2 wt.% of catalyst, methanol/oil mole ratio of 21:1, for 1 h in a batch reactor at 453 K. Kinetic analysis showed that the model based on mass transfer and chemical reaction at the catalyst surface confirmed the experimental data. Using that kinetic expression, the effect of continuous transesterification was proposed and verified by a 360-h long realized experiment in a laboratory packed-bed reactor (PBR). Slow deactivation of the catalyst was caused by leaching of Mn in both biodiesel and glycerol phases and by blocking the active sites of the catalyst with organic compounds.

To improve filtering effectiveness and avoid fouling, novel ultrafiltration (UF) polymer membranes were fabricated. These modified membranes were created by mixing varying concentrations of poly [2- (dimethyl amino) ethyl methacrylate] (PDMAEMA) with a homogeneous polyethersulfone (PES) casting solution that contained polyvinylpyrrolidone (PVP) as pore former. The effects on these blended membranes, as well as their hydrophilicity, anti-fouling properties, and filtering performance, were investigated. It was shown that adding more PDMAEMA to PES membranes enhanced the previously described characteristics as compared to pure PES membranes. Freshly modified PES membranes demonstrated a higher flux recovery ratio (FRR%) and enhanced water flow with the addition of PDMAEMA. Over the PES/PDMAEMA membrane, a pure water flux of 177.80 L·m-2 ·h-1 was recorded at a pressure of 0.1 MPa and 3.0 weight percent PDMAEMA, compared to the pure PES membrane, which recorded 67.20 L·m-2·h-1 under the identical conditions, which is much higher. Furthermore, the antifouling qualities of PES membranes were enhanced by the addition of PDMAEMA. Compared to normal PES membranes, which had a total fouling ratio (TFR) of 64.9%, the PES/PDMAEMA membranes designed for 3.0 weight percent PDMAEMA had a TFR of 36%. [ABSTRACT FROM AUTHOR]

Currently, the catalytic efficiency and reusability of the solid base catalysts cannot meet the demand of industrial biodiesel production under low temperature. The purpose of this study is to define the kinetics of heterogeneous transesterification process which might be used for the prediction of the biodiesel synthesis at high temperature and pressure. The focus in this study was paid to recently reported data obtained with different catalysts used for biodiesel synthesis in a batch reactor at high temperatures. It was shown that three kinetic models that include: a) irreversible first order reaction; b) reaction with changeable order; and c) resistances of mass transfer and chemical reaction at active sites of the catalyst could be applied for predicting the effect of high temperature of the transesterification. The apparent reaction rate constant of the irreversible first order reaction was determined, as well as the parameters of the other two, more complicated kinetic models. The best agreement was obtained with the more complicated models and the mean relative percent deviation between calculated and experimentally determined triacylglycerols conversion for these kinetic models is between 3 and 10%. [Projekat Ministarstva nauke Republike Srbije, br. 45001]

A mitochondria targeting dual‐action platinumIV prodrug exhibits high anticancer activity in triple negative breast cancer cells. The complex intervenes in several cellular processes including DNA damage, perturbation of mitochondrial bioenergetics and induction of necrosis to kill cancer cells. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emission is one of the well-known causes of global warming. Photoconversion of CO2 to useful chemical compounds using solar energy is an attractive approach as it reduces the major greenhouse gas and promises a sustainable energy source. This method involves radical-chain reactions that form cation and anion radicals generated as a result of the reaction with photogenerated electrons (e-) and holes (h+) between metal oxide photocatalyst and the reactants. Therefore, the product distribution of a modified photocatalyst even under specific reaction conditions is difficult to predict. The CO2 photocatalytic reduction process is controlled by several conditions such as reactor configuration, photocatalyst type, and nature of the reducing agents. Here, we review the parameters such as temperature, pH, CO2 pressure, type of reductant, role of co-catalysts, dopants, and type of photocatalysts that influence the end products of the photocatalytic reduction of CO2. In this review, the different modifications recommended for the photocatalysts to improve CO2 reduction and receive maximum valuable end product (methane, ethanol, methanol, hydrogen, and carbon monoxide) have been listed. The discussion also includes specific behaviors of photocatalysts which lead to different product distribution. It has been noted that different metal and nonmetal dopants improve the activity of a photocatalyst and influence the end product distribution by altering the active species. Similarly, the key factors, i.e. size, morphology and doping, which have been ruling the photocatalytic activity of CO2 reduction under UV or visible light irradiation have been identified. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emission is one of the well-known causes of global warming. Photoconversion of CO2 to useful chemical compounds using solar energy is an attractive approach as it reduces the major greenhouse gas and promises a sustainable energy source. This method involves radical-chain reactions that form cation and anion radicals generated as a result of the reaction with photogenerated electrons (e-) and holes (h+) between metal oxide photocatalyst and the reactants. Therefore, the product distribution of a modified photocatalyst even under specific reaction conditions is difficult to predict. The CO2 photocatalytic reduction process is controlled by several conditions such as reactor configuration, photocatalyst type, and nature of the reducing agents. Here, we review the parameters such as temperature, pH, CO2 pressure, type of reductant, role of co-catalysts, dopants, and type of photocatalysts that influence the end products of the photocatalytic reduction of CO2. In this review, the different modifications recommended for the photocatalysts to improve CO2 reduction and receive maximum valuable end product (methane, ethanol, methanol, hydrogen, and carbon monoxide) have been listed. The discussion also includes specific behaviors of photocatalysts which lead to different product distribution. It has been noted that different metal and nonmetal dopants improve the activity of a photocatalyst and influence the end product distribution by altering the active species. Similarly, the key factors, i.e. size, morphology and doping, which have been ruling the photocatalytic activity of CO2 reduction under UV or visible light irradiation have been identified. [ABSTRACT FROM AUTHOR]

Lack of proper wastewater management infrastructure is an alarming threat to the ground water quality, especially in developing countries. The objective of this study was to investigate the transport of coliform bacteria and other pollutants through soil to ground water in Taxila (Pakistan), near the unpaved sewage drain. An experimental setup was installed with five circular columns of variable depths of 0.3, 0.3, 0.9, 1.2, and 1.8 m clayey soil, taken near from drain, filled and compacted thoroughly in the columns. The sewage was poured into experimental setup from top and treated effluent was collected from the bottom. Sewerage before and after treatment were examined regularly. The Biological oxygen demand (BOD)5, Chemical oxygen demand (COD), Total suspended solids (TSS) and Total dissolved Solids (TDS), and coliform bacteria were monitored in the influent and effluent. Samples from the bores near the drain were also taken and analyzed. Coliform bacteria removal efficiency was 98.25%, in 1.8 m depth column, after 15th day of start. Similarly, BOD5, COD, and TSS maximum removal efficiencies achieved at 1.8 m depth were 90, 80, and 100%, respectively. Coliform bacteria were detected from the ground water near the sewage drain. A significant concentration of coliform bacteria was detected, even at the depth of 45 m, from the bores. [ABSTRACT FROM PUBLISHER]

The manganese carbonate catalyst, prepared by precipitation method, was used in transesterification of soybean oil under subcritical condition of methanol. Catalyst samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The triacylglycerol (TAG) conversion and fatty acid methyl esters (FAME) yield were determined using high performance liquid chromatography (HPLC). The transesterification was realized for 1 h using various working conditions: 0-3 wt.% of catalyst (based on the mass of oil), the mole ratio of methanol to oil from 13:1 to 27:1 and temperature ranging from 393 to 473 K. A maximum TAG conversion of 98.1% could be obtained at the optimal reaction conditions: 2 wt.% of catalyst, methanol/oil mole ratio of 21:1, for 1 h in a batch reactor at 453 K. Kinetic analysis showed that the model based on mass transfer and chemical reaction at the catalyst surface confirmed the experimental data. Using that kinetic expression, the effect of continuous transesterification was proposed and verified by a 360-h long realized experiment in a laboratory packed-bed reactor (PBR). Slow deactivation of the catalyst was caused by leaching of Mn in both biodiesel and glycerol phases and by blocking the active sites of the catalyst with organic compounds. [ABSTRACT FROM AUTHOR]

In this study, comparison and effect of Cinder supported with Lanthanum and Manganese oxide as catalyst for transesterification of triglyceride to methyl ester is proposed. The reaction mechanism along with the effects of methanol to oil molar ratio, amount of catalyst to oil, reaction temperature were also discussed. Moreover reusability of catalyst, catalyst resistance toward Free Fatty Acid and water were also discussed. The results show that yield of biodiesel produced with Mn:La:Cinder catalyst was 99% at ≥150 °C in 6 h. Cinder supported with Mn shows conversion of triglycerides from soybean oil in reaction with methanol after 6 h was over 99% at 150 °C. For both catalyst 3wt% of catalyst based on oil, 24:1 methanol/oil molar ratio was reused for 7 times with regeneration. The catalysts displayed great resistance toward 2.5% water and 1% wt fatty acids. [ABSTRACT FROM AUTHOR]

A mitochondria targeting dual-action platinum IV prodrug exhibits high anticancer activity in triple negative breast cancer cells. The complex intervenes in several cellular processes including DNA damage, perturbation of mitochondrial bioenergetics and induction of necrosis to kill cancer cells., (© 2021 Wiley-VCH GmbH.)