Sodium Methoxide

The most commonly used method for biodiesel preparation is via transesterification of vegetable oil using alkaline catalysts. Biodiesel yield and oil conversion are affected by operating conditions including the catalyst formulation and concentration. Application of alkaline catalysts can also lead to undesired soap formation. This study evaluated the alkaline catalyst effects on biodiesel yield and soap formation in transesterifying methanol and canola oil at different catalyst concentrations, reaction temperatures, and methanol-to-oil molar ratios. Four different alkaline catalysts, i.e., potassium hydroxide, sodium hydroxide, potassium methoxide, and sodium methoxide, were studied and compared on molar basis through a 4-factor 3-level experimental design. It was observed that methoxide catalysts led to better biodiesel yields than hydroxide catalysts. The methoxide catalysts not only accelerated the reaction but also elevated the conversion equilibrium. Based on statistical optimization, the operating conditions for maximizing biodiesel yield and minimizing soap formation were potassium methoxide as catalyst at 0.2 mol/mol (1.59%wt), reaction temperature of 505C, and methanol-to-oil molar ratio of 4.5:1. Experimental verification gave 95.8% biodiesel yield and 0.75%wt soap.

The result of the investigation on methyl esters obtained on the basis of used sunflower oil, rapeseed oil and soybean oil are given in this paper. Transesterification reaction conditions that affect yield and purity of the product esters including oil quality, type and concentration of catalyst, temperature and reaction time were examined. Methanol esterification of different oils at 60 0C with 1-10 % (v/v) sodium met-oxide was studied. With appropriate percent of sodium met-oxide, temperature 60 0C and 1 hour, all investigated oils were sufficiently transesterified and could be used as fuel in diesel engines.

The chemical syntheses of 6,7-(a-pyridyl)-I-(lJ,5-tri-O-benzoy-~-0-ribofuranosyl)-lumazinc (6) and the corresponding free nucleoside 7 are desclibed. Thiation of 6 with P 4 SIO gave a salt type adduct derivative of 4thiolumazine 8 which afforded the frce nucleosidc 9 on deblocking. Treatment of 8 with methanolic NHJ gave the isopterin-N-l nucleoside 10. 2,2' -Anhydro compound 13 was obtained by the diphenyl carbonate technique and characterised as the diacetate 14. Acid hydrolysis of 14 gave the arabino-nucleoside 15. which was isolated also from hydrolysis of 14 with hydroxide ion. Reaction of 7 with acetyl bromide gave the l'-bromo-2'-deoxy derivative 11 as minor product together with triacetate 12 as the main analogue. Reduction of the bromo function in 11 into the expected l'-deoxy analogue during the treatment with tri-n-butyltin hydride has failed and the 2.2' -anhydro compound 15 was the only product isolated. Alternati-\•ely. the 6,7-bis-(a-pyridyl)-1-(2-deoxy-3.5-di-O-toloulyl-a and ~-D-ribofuranosyl)-Iumazine (17) and ( ) were synthesized from direct condensation of sugar 16 and the silylated base 4. Debo\Cking of 17 and 19 with sodium methoxide gave the free analogues 18 and 20 respectively.

This research investigates the process simulation of sodium methoxide (NaOCH3) synthesis from methanol (CH3OH) and sodium hydroxide (NaOH) under three synthesis schemes: schemes A, B, and C. Scheme A consisted of one equilibrium reactor and two distillation columns, scheme B one reactive distillation column and one distillation column, and scheme C one reactive distillation column and pervaporation membrane. The simulation parameters included CH3OH/NaOH feed flow ratio (1.2-1.6), number of stages (5-30), bottom flow rate (1400-1600 kg/h), and feed stage location (5, 10, 15, 20, 21, 22, 23, and 24). The simulation parameters were varied to determine the optimal NaOCH3 synthetic conditions under different schemes with 0.01 wt% water content, maximum 45 wt% NaOCH3, and the lowest total energy consumption. The results showed that scheme C had the lowest total energy consumption (34.25 GJ/h) under the optimal synthetic condition of 1.4 for CH3OH/NaOH feed flow ratio, 25 for the number of...

Aim: To synthesize some hydrazones with xanthine structure and to evaluate their antioxidant activity. Material and methods: The synthesis started from theophylline sodium salt, prepared from theophylline and sodium met hoxide, which was transformed into its ethyl ester and then in hydrazide. The hydrazo ne derivatives were obtained by the condensation of hydrazide with different aromatic aldehydes (benzaldehyde, 4-nitro/3-nitro/3-hydroxy/4-chloro/4-bromo-benzaldehyde). The antioxidant potential was evaluated in vitro by using the DPPH radical scavenging assay and was compared with theophylline activity used as parent compound. Results: Six hydrazones with xanthine structure were obtained. They were characterized in terms of their physical properties and their structures were confirmed by IR and 1 H-NMR spectroscopy. Some of these compounds have an antioxidant effect more pronounced than theophylline at higher concentrations. The most active compound was 3-nitro-benzylidene-hydrazino-acetyl-theophylline (compound g), with an inhibition rate of 65% ± 0.99 at 30 min and 79% ± 0.81 at 60 min. Conclusions: The antioxidant activity of synthesized hydrazones depends on the substituents used in structural modul ation. The substitution of aromatic ring with nitro group in meta position had the most favorable influence.

Study of biodiesel production through in situ ethanolysis of Jatropha curcas was conducted by investigating the effect of reaction time, reaction temperature, type of catalysts and their concentration. Base catalysts such as sodium hydroxide, potassium hydroxide and sodium methoxide were used to enhance the reaction which was carried out in a batch system. The fatty acid ethyl ester content in the reaction mixture was determined by gas chromatography based on ASTM D 6584. The highest yield of the ethyl ester achieved was 99.98% under the optimum conditions: 2.0 wt.% of CH 3 ONa, reaction temperature of 30 °C and 2 h of reaction time. The biodiesel properties for instance flash point, viscosity, acid value and total glycerine meet the specification of the ASTM D 6751-07a.

The synthesis of steroidal heterocycles containing the pyrazole and pyrimidine ring fused to the 16,17-position of the steroid nucleus is reported. Androstenolone acetate (1) reacted with carbon disulfide, iodomethane and sodium hydride to furnish 3βacetoxy-16-[bis(methylthio)methylene]-5-androst-5-en-17-one (2). The reactions of 2 with hydrazine hydrate and methylhydrazine afforded the 5 '-methylthiopyrazolo[4',3':16,17]androst-5-en-3β-ols 3a and 3b, respectively. Treatment of 2 with amidinium, guanidinium, and isothiuronium salts in the presence of sodium methoxide yielded the 6'-methoxy-pyrimido [5',4':16,17]androst-5-en-3β-ols (4a-4e).

Nano studies of added halide ions in 0.1M ammonium oxalate to zircaloy-4 have been investigated by faraday 1st law through anodic polarization technique (galvanostatic technique). Kinetics of anodic polarization of zircaloy-4 have been studied at a constant current density of 8 mA.cm-2 at room temperature. Thickness estimates were made from capacitance data and faradaic data in nanometers. The anodization voltage; Thickness of Capacitance,Thickness of Faradaic; anodization rate, faradaic efficiency and field strength were calculated based on the plots. Kinetics of anodic polarized zirconia oxide coloured films was observed by the addition of millimolar concentration of anions (Cl-, Br-, I-). By the incorporation of halide ions on the zirconia samples was better improved by the investigatation of research sqamples. The anodization rate, faradaic efficiency and field strength investigated. Zirconium based alloys are used as structural material in Nano Studies … Dr J. Padmaja et al.

Anodization of zircaloy-4 in 0.1 M sodium hydroxide has been carried out. Kinetics of anodic oxidation of zircaloy-4 has been studied at a constant current density of 8 mA.cm-2 and at room temperature. Thickness estimates were made from capacitance data. The plots of formation voltage vs. time, 1/C vs. Time [or] Thickness by capacitance vs. Thickness by Faradaic, and Formation voltage vs. Thickness by capacitance were drawn and rate of formation, current efficiency and differential field were calculated. The addition of solvent (glycerol) showed better kinetic results in aquo-glycerolic media. For 25%, 50% and 75% aquo-glycerolic media, the dielectric constant values are low leading to a marked improvement in the kinetics .In 80% glycerol, though the dielectric constant value of solution is less, the kinetics was slow which may be attributed to the fact that the electrolyte becomes highly non-polar. Improvement in the kinetics of oxide film formation was observed by the addition of millimolar concentration of anions (SO 4 2-, CO 3 2-,). The presence of carbonate ions improved the kinetics of anodization to better extent.

The surface of zircaloy-4 anodized at a constant current density of 4mA.cm ethylene glycol at a potential 0–187V, was characterized by means of surface science technique AFM with micro and nanostructures. It was found that d homogeneous coverage on zr-4 surface modifying the topography. The incorporation of oxalate dianions from the electrolyte and ethylene glycol solvent to the surface during the anod oxide films grown with relatively high voltages, the oxide formed over the Zr rougher and protruded. Anodic oxide films were homogeneous and rough with nanosized grains. When the anodization voltage was 187 V the average roughness (Ra) of the anodic film reached 5.9nm, and the oxide formed changed abruptly to become as rough as that formed on non

Anodization of zircaloy-4 in 0.1M ammonium oxalate has been carried out. Kinetics of anodic oxidation of zircaloy-4 has been studied at a constant current density of 8mA.cm-2 and at room temperature. Thickness estimates were made from capacitance data. The plots of formation voltage vs. time, reciprocal capacitance vs. time, reciprocal capacitance vs. formation voltage and thickness vs. formation voltage were drawn. From these plots rate of formation; current efficiency and differential field were calculated. The addition of solvent (methanol) showed better kinetics results. For 25%, 50% and 75% aquo-methanolic media, the dielectric constant values are low leading to a marked improvement in the kinetics. In 80% methanol, though the dielectric constant value of solution is less, the kinetics was slow which may be attributed to the fact that the electrolyte becomes highly non-polar.

Anodization of zircaloy-4 in 0.1 M sodium hydroxide has been carried out. Kinetics of anodic oxidation of zircaloy-4 has been studied at a constant current density of 8 mA.cm and at room temperature. Thickness estimates were made from capacitance and faradaic data. The plots of anodization voltage vs. anodization time, Thickness by Capacitance vs. Thickness by Faradaic, and anodizat ion rate, faradaic efficiency were calculated. Kinetics of anodic polarized oxide film formation was observed by the addition of millimolar concentration of anions (I ̄ ) . By the addition of iodide ions to the sodium hydroxide there was better improvement in th e anodization rate, faradaic efficiency but there is not that much improvement i the field strength. The micro structural characterization of zirconia was studied by XRD. The anodic oxide layer is composed of cubic phase. The crystallite sizes are not stable in nanometers. .

Oximation of indoles having a methoxycarbonylamino group on C 5 and an acyl group on C 3 with hydroxylamine hydrochloride in the presence of pyridine gave the corresponding oximes. The reduction of the 3-C=O group with sodium tetrahydridoborate in the presence of sodium hydroxide was accompanied by removal of the methoxycarbonyl group at the pyrrole nitrogen atom with formation of racemic alcohols. 1,4-Addition of 1-(pyridin-3-yl)butane-1,3-dione to dimethyl 1,4-benzoquinone diimine N,N′-dicarboxylate in dioxane in the presence of sodium methoxide, followed by heating in boiling 22% hydrochloric acid, afforded methyl 2-methyl-5-(methoxycarbonylamino)-3-(pyridin-3-ylcarbonyl)-1H-indole-1-carboxylate. 3-(Dimethylamino)-1-(4-methyl-1,2,5-oxadiazol-3-yl)prop-2-en-1-one reacted with N,N′-bis(methoxycarbonyl)-and N,N′-bis(phenylsulfonyl)-1,4-benzoquinone diimines in methylene chloride and acetic acid, respectively, in the presence of BF 3 • Et 2 O to produce indoles having a 1,2,5-oxadiazolylcarbonyl group on C 3 .

The kinetics of anodic oxidation of niobium have been studied in 0.1M L-ascorbic acid without and with addition of a millimole of sodium phosphate at a constant current density of 8 mA.cm-2 and at room temperature (300 K). The addition of phosphate ions found to improve the kinetics of film formation. This trend and mechanism of anodic oxide film growth is confirmed from radio-tracer studies using labeled phosphate ions. The conclusion of the results obtained is migration of anion impurity and accumulation of active phosphate in the inner layers of the oxide film formed.

The kinetics of anodic oxidation of niobium have been studied in 0.1M L-ascorbic acid without and with addition of a millimole of sodium phosphate at a constant current density of 8 mA.cm -2 and at room temperature (300 K). The addition of phosphate ions found to improve the kinetics of film formation. This trend and mechanism of anodic oxide film growth is confirmed from radio-tracer studies using labeled phosphate ions. The conclusion of the results obtained is migration of anion impurity and accumulation of active phosphate in the inner layers of the oxide film formed.

Highlights  Galvanostatic technique by faraday 1st law of zirconia ceramics as implant material  The growth kinetics of zirconia studied at constant current densities  Investigated the ionic current density on differential field strength  The half-jump distance and height of the energy barrier deduced by Cabrera-Mott theory.

Anodic polarization of zircaloy-4 in 0.1 M oxalic acid dihydrate has been carried out by Faraday 1 st law. Kinetics of anodic oxidation of zircaloy-4 has been studied at a constant current density of 8 mA.cm -2 and at room temperature. Thickness estimates were made from capacitance and faradaic data. The plots of anodization voltage vs. anodization time, Thickness by Capacitance vs. Thickness by Faradaic, and anodization rate, faradaic efficiency were calculated. Kinetics of anodic polarized coloured zirconia film was observed by the addition of millimolar concentration of anions (Cl¯). By the addition of chloride ions to the oxalic acid dihydrate was better improvement in the anodization rate, faradaic efficiency field strength.

The anodic polarization process was carried out from 273K-333K temperature with voltage range of 79V to 60V, which is the voltage range achievable by the anodization circuit.The effect of voltage formed via anodic polarization of high purity zircaloy-4 was investigated. It is observed after the anodic polarization of zircaloy-4 by faraday 1 st law process when we raised the temperature from 273K-333K observed that at constant current density 8 mA.cm¯² a decrease in the zirconia plate rate, faradaic efficiency and differential field.

The 3-monochloropropane-1,2-diol (3-MCPD) and 3-MCPD esters were found in any type of refined vegetable oil -mostly produced during the refining process-and recognized as emerging food contaminants. Several analytical methods have been developed and one of which was a Weißhaar's method. The study aims to validate the modified Weißhaar's method for analysis of 3-MCPD and 3-MCPD esters in refined palm oil. Ion fragments were used for identification and quantification of 3-MCPD and 3-MCPD-d5. 3-MCPD was determined by GC-MS after released from its ester by transesterification with sodium methoxide and derivatized with phenylboronic acid. The validation showed that liniarity response (r=0.994) was observed from a linear regression by using external standard and internal standard at a concentration range of 0.008 and 0.377 µg mL -1 . The LOD of the validated method was 0.06 µg g -1 while its LOQ was 0.20 µg g -1 , precision (relative standard deviation, RSD) was 6.16%, and accuracy (as percentage of recovery) was in the range of 95.83-113.27%. This results indicated that the modified method was valuable and sensitive for detection of 3-MCPD and 3-MCPD esters. Using the validated method, 3-MCPD esters content of a commercial palm oil sample was determined and calculated as the difference between total 3-MCPD and free 3-MCPD, which was 13.24 µg g -1 . Total 3-MCPD content of several palm oils were at a concentration range of 13.94-34.52 µg g -1 . These results also showed that there was a correlation between 3-MCPD with diacylglyceride (DAG). Samples with DAG content gave a high test results of 3-MCPD with a coefficient of correlation of r=0.752.

Objective: To evaluate the effect of novel sonochemical silver nanorods on HIV and herpes simplex virus type 1 (HSV-1) viruses in human cervical cancer HeLa cells. Methods: The formation of silver nanorods conjugated with sodium 2-mercaptoethane sulfonate (Ag-MES) was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and thermal gravimetric analysis. The antiviral activity of this Ag-MES was examined against HIV and HSV-1 virus replication. The characterizations of Ag-MES and physiochemical structure were determined by scanning electron microscopy, Fourier transform infrared spectroscopy and thermal gravimetric analysis. Approximately entire viral replication was inhibited by Ag-MES at 10 µmol/mL concentration. About 90% of HSV virions failed to replicate in the present of this concentration of nanorods. However, HIV showed more sensitivity to Ag-MES than HSV-1. Conclusions: According to the obtained data, the synthesized sonochemical silver nanorod in this study is a promising candidate for further drug discovery investigation.

5‐Formyl‐1‐(2,3,5‐tri‐O‐acetyl‐β‐D‐ribofuranosyl)uracil (4) was synthesized from 5‐formyluracil (2) and 1,2,3,5‐tetra‐O‐acetyl‐β‐D‐ribofuranose (3) and condensed with 2‐thiohydantoin derivatives 5 by using piperidine as the catalyst to give 5‐(uridin‐5‐ylmethylene)‐2‐thiohydantoin (8a) and 3‐phenyl‐5‐(uridin‐5‐ylmethylene)‐2‐thiohydantoin (8b) after deprotection with sodium methoxide in methanol. Compound 8a was also obtained in an inversed reaction sequence from 5‐formyluracil starting with condensation with 2‐thiohydantoin and then with 3. The compounds 8a and 8b did not show any activity against HSV‐1 or HIV‐1. magnified image

Introduction: Deplastination is a process that reverses plastination. While the process is in its infancy, this study was designed to see if deplastinated tissues can be used for histopathological studies. Methods: In this study, a slice of liver tissue was split into two parts. The first half was processed, sectioned and stained with routine H&E staining while the other half was plastinated with S10 plastination technique and was deplastinated after 3 months using sodium methoxide as the deplastinating agent. It was latter stained with routine H&E. The slides were assessed qualitatively on parameters like tissue and cell identification, staining property, preservation of tissue architecture, visualisation of intracellular structures like nuclei, nucleoli, fat goblets etc. and presence of artefacts due to the process. Results: Identification of tissue was possible on the deplastinated slides. Intracellular structures like nuclei, nucleoli, fat droplets were identified in the deplastinated slides. Discussion: In this study, we have found that sodium methoxide and methanol form good deplastinating agents for small sections of tissue. Identification of endpoint of deplastination forms a crucial step in the process.

Biodiesel production is generally catalyzed by potassium methylate or sodium methylate catalysts based on KOH and NaOH and these catalysts are still imported. The search for a cheap and effective catalyst continues to be carried out by researchers. One of the catalyst support materials currently in use involves impregnating K 2 CO 3 with various substances, resulting in a heterogeneous catalyst. In this study, it was tried to use K 2 CO 3 dissolved in methanol to produce a homogeneous potassium methylate catalyst. Potassium methylate-based homogeneous catalyst K 2 CO 3 -methanol is proven to have a very high function in the transesterification reaction of Refined Bleached Deodorized Palm Oil (RBDPO) into biodiesel, this is evidenced by the use of a catalyst percentage of 2% w and 30% w methanol to the weight of RBDPO resulting in an acid content in biodiesel of only 0.12% and a total glycerol of 0.124% in reaction time 3 hours, with the purity of the methyl ester in biodiesel reaching 98.80%. Meanwhile, for the calculation of homogeneous reaction kinetics, a reaction rate equation is produced where the order of the RBDPO transesterification reaction is order 2 (two) and the reaction rate constant is 0.0044. Catalyst, K 2 CO 3 , RBDPO, Kinetics of Homogeneous Reactions

Biodiesel is an alternative fuel that can be easily produced through transesterification with the assistance of a catalyst. Palm oil is a widely utilized feedstock for biodiesel production due to its abundant availability. In this study, a catalyst was synthesized using chitosan (CS) modified with ethylenediamine (EDA) and cross-linked with epichlorohydrin (ECH) for a catalyst heterogeneous in transesterification reaction. The resulting product (CS/EDA/ECH) was characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Its performance was evaluated for biodiesel production. The CS/ECH/EDA catalyst achieved optimal reaction conditions with 5% EDA concentration at room temperature, an oil: methanol ratio of 1:1 (v/v), a total volume of 10 mL of oil and methanol, and a catalyst mass of 0.75 grams. The methyl esters formed corresponded to the fatty acid content in palm kernel, namely methyl palmitate, methyl 9,10-octadecadienoate, methyl oleate, methyl 12,13-tetradecadienoate, and methyl stearate with the highest methyl ester conversion is methyl oleate. The CS/ECH/EDA catalyst exhibited consistent performance after three use cycles.

Described are the design, synthesis, and structures of three nonpolar nucleoside isosteres to be used as probes of noncovalent bonding in DNA and as isosteric replacements for the natural nucleosides in designed nucleic acid structures. Reaction of substituted aryl Grignards with 3′,5′-bis-O-toluoylα-deoxyibofuranosyl chloride and subsequent deprotection with sodium methoxide in methanol afforded the two β-C-nucleoside pyrimidine analogs 1 and 2. The dimethylindolyl nucleoside 3, a purine isostere, was obtained by a nucleophilic displacement on α-chlorodeoxyribofuranose by the sodium salt of 4,6-dimethylindole, followed by deprotection. Regio-and stereochemistry of the products were established with NOE difference spectra and 1 H NMR splitting patterns. Analogs 1 and 2 are nonpolar isosteres of thymidine, and nucleoside 3 is an isostere of 2-aminodeoxyadenosine, the triply-bonded Watson-Crick partner of thymidine. Semiempirical AM1 calculations were carried out to provide bond length information to assess structural similarities between the isosteres and their natural counterparts.

The orthoselectivity and high yield are two significant subjects which should be studied more in the process of hydroxybenzaldehydes or salicylaldehyde production. In this work, salicylaldehyde was synthesized by the reaction of formaldehyde and phenol magnesium methoxide complex, in an anhydrous medium. In order to achieve a selectively orthoformylated product, at first the hydroxyl group of phenol was rearranged by magnesium methoxide. The phenol magnesium salt was then formylated by paraformaldehyde. Impurities of the resulted salicylaldehyde were removed by several steps of liquid extracting via water and acid washing. The spectroscopic data of FT-IR, 1 H NMR (500 MHz), and GC/MS on the final product were recorded and interpreted. The results of FT-IR spectrum and integration value of 1 H NMR spectrum imply on the high conversion of reaction. The GC/MS spectrum also shows that the amounts of by products are low enough.

Finding a long-term solution to the world's growing dependence on conventional energy sources and the depletion of fossil fuels is what worries scientists the most right now. An alternative that appears promise is biodiesel. It was investigated how to increase the generation of biodiesel from leftover fish processors' oil using sodium methoxide and sulphonated eggshells as a catalyst, based on Box-Behnken design. The greatest yield of 96.81% was achieved at 1:12 oil to methanol ratio, 65 °C reaction temperature, 90 minutes, and 0.5 w/w% catalysts loading. The variables constant, methanol to oil ratio, reaction temperature, reaction time, reaction temperature* reaction temperature, and methanol to oil ratio*catalyst load all had a significant effect on the biodiesel production, according to the response surface regression. The model does a good job of accounting for the link between biodiesel and process variables. Thus, residual fish processor oil might be effectively conver...

The most commonly used method for biodiesel preparation is via transesterification of vegetable oil using alkaline catalysts. Biodiesel yield and oil conversion are affected by operating conditions including the catalyst formulation and concentration. Application of alkaline catalysts can also lead to undesired soap formation. This study evaluated the alkaline catalyst effects on biodiesel yield and soap formation in transesterifying methanol and canola oil at different catalyst concentrations, reaction temperatures, and methanol-to-oil molar ratios. Four different alkaline catalysts, i.e., potassium hydroxide, sodium hydroxide, potassium methoxide, and sodium methoxide, were studied and compared on molar basis through a 4-factor 3-level experimental design. It was observed that methoxide catalysts led to better biodiesel yields than hydroxide catalysts. The methoxide catalysts not only accelerated the reaction but also elevated the conversion equilibrium. Based on statistical optimization, the operating conditions for maximizing biodiesel yield and minimizing soap formation were potassium methoxide as catalyst at 0.2 mol/mol (1.59%wt), reaction temperature of 505C, and methanol-to-oil molar ratio of 4.5:1. Experimental verification gave 95.8% biodiesel yield and 0.75%wt soap.

Dedico este trabalho a toda minha família, em especial aos meus pais, Galvão e Marli, aos meus irmãos Elesandro, Ezequiel, Rodrigo e Claudione, ao meu amigo e irmão Jorge e sua esposa Zélia Passos e aos meus tios Silvio e Luzia pelo incentivo e apoio que tive em todos os momentos da minha vida. Também, aos meus queridos amigos da Comunidade Sócio-Educativa/FASERS e PUCRS. AGRADECIMENTOS Primeiramente, agradeço a Deus por todas as minhas conquistas, minha família, amigos, trabalho e por não deixar-me nunca esmorecer diante das adversidades nesta caminhada. Aos meus pais, Galvão e Marli, por terem me dado a vida, amor e carinho. Ensinado princípios e valores, assim como me mostrarem que a vida nos possibilita vários caminhos, e quem escolhe qual seguir, somos nós. Agradeço à orientação da professora Rosane Ligabue e coorientação da professora Jeane Dullius, pelo incentivo, oportunidade de aprendizado pessoal e profissional, desde a graduação, passando pela iniciação científica e neste mestrado. A vocês, minha eterna gratidão e meu muito obrigado! Agradeço, aos professores Tiziano Dalla Rosa, André Arigony, Luiz Ernani, Marcus Seferin e Carlos Carone, pela ajuda e ensinamentos no laboratório ou em sala de aula. Muito obrigado! A todos os funcionários da Faculdade de Química (Almoxarifado: Luciane, Roberto, Marcos, Paulo e Fernando, Vidreiro: Nelson e Secretaria: Nilza, Neiva e Luciana) pela amizade e colaboração no desenvolvimento deste trabalho. Ao meu grande amigo e colega Leonardo Moreira dos Santos, pela troca de conhecimentos. Ao professor Rogério Lourega, Lia, Andressa e Flávio do Centro de Excelência em Pesquisa e Inovação em Petróleo, Recursos Minerais e Armazenamento de Carbono (CEPAC) da PUCRS. A todos os colegas e amigos do Laboratório de Organometálicos e Resinas

Coconut oil based low temperature liquid hair oil formulations have been developed with Coconut oil's ethyl ester and butyl ester modifications. Ethyl alcohol and butyl alcohols were used for trans-esterification of the Coconut Oil using sodium methoxide chemical and Eversa Transform 2.0 Lipase enzyme catalysts. The sodium methoxide catalyst used was 0.4% for interesterification of the ethyl and butyl esters with coconut oil at115ºc for 1 hours. The Ethyl Esters (E.E.) obtained had 0°C Solidification Point (S.P.) and butyl Esters (B.E.) (-2ºC) S.P. by using chemical catalyst. The enzymatic Method resulted (-2ºC, S.P.) Ethyl Esters and (-5º C, S.P. ) Butyl Esters products. The ester-ester interchange reaction of Coconut Oil with E.E. and B.E. yielded the hair oil formulations of the required S.P. of below 5ºC at optimum ratio. The physical properties of the low temperature hair oil formulations were analysed and compared with the market samples of the leading brands of the coconut oil based hair oils for winter use.

This work focused on the application of adaptive neuro-fuzzy inference system (ANFIS) and response surface methodology (RSM) as predictive tools for production of fatty acid methyl esters (FAME) from yellow oleander (Thevetia peruviana) seed oil. Two-step transesterification method was adopted, in the first step, the high free fatty acid (FFA) content of the oil was reduced to <1% by treating it with ferric sulfate in the presence of methanol. While in the second step, the pretreated oil was converted to FAME by reacting it with methanol using sodium methoxide as catalyst. To model the second step, central composite design was employed to study the effect of catalyst loading (1-2 wt.%), methanol/oil molar ratio (6:1-12:1) and time (20-60 min) on the T. peruviana methyl esters (TPME) yield. The reduction of FFA of the oil to 0.65 ± 0.05 wt.% was realized using ferric sulfate of 3 wt.%, methanol/FFA molar ratio of 9:1 and reaction time of 40 min. The model developed for the transesterification process by ANFIS (coefficient of determination, R 2 = 0.9999, standard error of prediction, SEP = 0.07 and mean absolute percentage deviation, MAPD = 0.05%) was significantly better than that of RSM (R 2 = 0.9670, SEP = 1.55 and MAPD = 0.84%) in terms of accuracy of the predicted TPME yield. For maximum TPME yield, the transesterification process input variables were optimized using genetic algorithm (GA) coupled with the ANFIS model and RSM optimization tool. TPME yield of 99.8 wt.% could be obtained with the combination of 0.79 w/v catalyst loading, 12.5:1 methanol/oil molar ratio and time of 58.2 min using ANFIS-GA in comparison to TPME yield of 98.8 wt.% using RSM. The TPME structure was characterized using Fourier transform infra-red (FT-IR) spectroscopy. The results of this work established the superiority of predictive capability of ANFIS over RSM.

The 3-monochloropropane-1,2-diol (3-MCPD) and 3-MCPD esters were found in any type of refined vegetable oil-mostly produced during the refining process-and recognized as emerging food contaminants. Several analytical methods have been developed and one of which was a Weißhaar's method. The study aims to validate the modified Weißhaar's method for analysis of 3-MCPD and 3-MCPD esters in refined palm oil. Ion fragments were used for identification and quantification of 3-MCPD and 3-MCPD-d5. 3-MCPD was determined by GC-MS after released from its ester by transesterification with sodium methoxide and derivatized with phenylboronic acid. The validation showed that liniarity response (r=0.994) was observed from a linear regression by using external standard and internal standard at a concentration range of 0.008 and 0.377 µg mL-1. The LOD of the validated method was 0.06 µg g-1 while its LOQ was 0.20 µg g-1 , precision (relative standard deviation, RSD) was 6.16%, and accuracy (as percentage of recovery) was in the range of 95.83-113.27%. This results indicated that the modified method was valuable and sensitive for detection of 3-MCPD and 3-MCPD esters. Using the validated method, 3-MCPD esters content of a commercial palm oil sample was determined and calculated as the difference between total 3-MCPD and free 3-MCPD, which was 13.24 µg g-1. Total 3-MCPD content of several palm oils were at a concentration range of 13.94-34.52 µg g-1. These results also showed that there was a correlation between 3-MCPD with diacylglyceride (DAG). Samples with DAG content gave a high test results of 3-MCPD with a coefficient of correlation of r=0.752.

N-and S-galactosylation was carried out via the reaction of 5-((Z)-arylidene)-2-thioxo-4-thiazolidinones with 2,3,4,6-tetra-O-acetyl-a-D-galactopyranosyl bromide under alkaline conditions or under silylation conditions. Deacetylation of the N-galactosylation products was performed with concentrated hydrochloric acid in methanol (3.5%) or sodium methoxide in methanol without cleavage of the 2-thioxo-4-thaizolidinone ring by means of acid hydrolysis. The anomers were separated by flash column chromatography, and their configurations were assigned by NMR spectroscopy. The deprotected nucleosides were screened against leukemia L-1210 and were found inactive.

Interesterification is an alternative to partial hydrogenation that helps to manufacture products of a variety of melting properties. When the process is applied to different blends of vegetable oils, redistribution of fatty acids between and within triacyglycerol occurs that changes the physical properties especially the melting characteristics of the vegetable oil blends. For chemical interesterification process, unrefined vegetable oils (soybean oil and cottonseed oils) were obtained from the local industry (United Industries Faisalabad, Pakistan). Different blends of soybean and cottonseed oils were prepared ranging from 100% soybean oil to 100% cottonseed oil in 25% increments (w/w) with different ratios of (100% : 0%, 75% : 25%, 50% : 50%, 25% : 75%, 0% : 100%) respectively. The blended oil portions (500mL) were neutralized and dried. For chemical interesterification sodium methoxide was used as catalyst. At the end of reaction, the catalyst was inactivated and reaction was st...

Abstract⎯Chemical recycling of polyethylene terephthalate (PET) to produce terephthalic acid (TPA) was studied using in situ hydrolysis with sodium methoxide in methanol and dimethyl sulfoxide (DMSO) as solvent under microwave irradiation. The microwave-assisted reaction was carried out at different temperatures, and reaction time between 5 to 30 min. High degrees of depolymerization were examined at temperature near 70°C at microwave power 300 W. The reaction was carried out in a sealed microwave reactor in which the time and temperature were controlled and recorded. The products were mainly monomers such as TPA and ethylene glycol (EG) which were isolated and purified for further analysis. Monomethyl terephthalate, dimethyl terephthalate, and terephthalic acid were formed initially then converted to TPA as a single monomer product. Purified, TPA was analyzed and identified by NMR, TGA, DSC and FTIR. It was observed that the reaction greatly depends on the amount of sodium methoxide, the volume of methanol and DMSO used, the reaction time, and temperature. Compared to conventional heating methods, the time needed to achieve complete degradation of PET was significantly reduced to 5 min by using microwave irradiation and sodium methoxide catalyst. This has led to substantial saving in energy and cost supporting the conclusion that this proposed recycling process is very beneficial for the recycling of PET wastes.

The process involving a rearrangement of pyrrolidino[3,4-c]pyrrolidine to another pyrrolidino[3,4-b]pyrrolidine using sodium methoxide as base is fully studied. The effects of the substituents are analyzed during the ring-opening/ring-closing sequence. Computational studies are also performed to explain the importance of susbstituents and quaternary carbons, especially when the (3-indolyl)methyl is present in the starting material. Finally, all the samples are evaluated as potential candidates for antibacterial and antimycobacterial activities.

This article describes the synthesis of the new (2Z)-2-(4-methoxybenzylidene)-6-nitro-4H-benzo[1,4]thiazin-3-one, (2Z)-2-(4methoxybenzylidene)-4-methyl-6-nitro-4H-benzo[1,4]thiazin-3-one, (2Z)-6-amino-2-(4-methoxybenzylidene)-4H-benzo[1,4] thiazin-3-one, (2Z)-6-butylamino-2-(4-methoxybenzylidene)-4-methyl-4H-benzo[1,4]-thiazin-3-one and (2E)-N-alkyl-N-(2hydroxy-5-nitrophenyl)-3-phenylacrylamides and the spectroscopic data. The arylidenebenzothiazine compounds were prepared using the Knoevenagel condensation with substituted benzaldehydes in the presence of sodium methoxide in DMF. The presence of a nitro substituent in the 4-position, water and a slightly acid reaction medium in this condensation caused the rupture of the benzothiazine ring and subsequent formation of the phenylacrylamide compounds. A crystallographic data was presented for (2E)-3-(4-bromophenyl)-N-dodecyl-N-(2-hydroxy-5-nitrophenyl) acrylamide.

Prime steam lard obtained from pig fat by rendering was characterized and refined. The lard was transesterified with methanol and sodium hydroxide (as catalyst) at 40, 50, 60, and 70°C. Fuel properties of the fatty acid methyl esters (FAME) or biodiesel were determined alongside that of petroleum derived diesel obtained commercially. Results obtained showed that the saponification and iodine values of the lard were 198 and 64.08, respectively, while the flash point and viscosity were 203°C and 47.87 mm 2 s-1 , respectively. While the refractive index of the methyl esters decreased with increase in temperature from 1.4480 to 1.4430 (1.4459 ± 0.0022), the specific gravity increased from 0.860 to 0.875. The flash point and the pH of the biodiesel samples were 134.25°C ± 1.71°C and 7.05 ± 0.03, respectively, and the viscosity was 4.23 ± 0.1 mm 2 s-1. The flash point, iodine value, viscosity, cetane index, and the specific gravity of the petrodiesel were 79°C, 84, 3.12, 46, and 0.84, respectively. The values obtained for the FAME are within the standard limits and compares well with that reported in the open literature. It can be used alone or in blends with petrodiesel to run compression ignition engines.

ChemInform Abstract The piperideinium bromide (III) undergoes several conversions as outlined in the reaction scheme. Treatment of (III) with diazomethane (II) produces a mixture of the piperidinopyrrolidone (Ia) and the corresponding fused γ-lactone (Ib). Reaction of (III) with various nucleophiles results in ring-contraction, forming the pyrrolidines (V), (VIII), (IX), or (XI).

The preparation of a poly(maleimide‐ether) containing pendent thiophene rings via the reaction of 2‐(3‐thienylmethyl)‐1,3‐N,N&#39;‐bis(3,4‐dichloromaleimido) propane with 1,4‐dihydroxybenzene is described. The novel 2‐substituted‐1,3‐N,N&#39;‐bis(3,4‐dichloromaleimido) propanes were obtained by allowing their corresponding diamine hydrochlorides to react with 3,4‐dichloromaleic anhydride in acetic acid in the presence of sodium methoxide. The diamine hydrochlorides were prepared by the reduction of their respective diamides. The poly(maleimide‐ether)s were fully characterized and 13C‐NMR spectroscopy was used to confirm the microstructure of the materials. The properties of the thiophene substituted polymer are compared with model poly(maleimide‐ether)s. Electrochemical studies indicated that the thiophene rings in the thiophene‐substituted poly(maleimide‐ether) were not electroactive. © 1992 John Wiley & Sons, Inc.

Biodiesel is considered an important substitute of diesel oil. Traditionally, it is obtained by the transesterification of vegetable oils with methanol or ethanol, catalyzed by NaOH or KOH. Heterogeneous catalysts have been studied with the aim at facilitating and diminishing costs with purification stages. In the present work, the Na/Nb2O5 system was evaluated on the reaction of soybean oil with ethanol. It was verified, by DRX and IR, that the niobia calcined at 500ºC and impregnated with sodium underwent greater structural alterations than that treated at 300°C. These modifications allowed the generation of basic properties on niobia surface (Hammett and CO2 adsorption /IR). This catalyst showed the highest conversion (30%) among the used materials. The method chosen for evaluating the catalysts yield was the 1H NMR spectroscopy.