Lee et al. (2003) reported a new method for the determination of the methyl, ethyl and isopropyl esters of methanesulfonic acid, and of dimethyl sulfate. Derivatisation with aqueous sodium thiocyanate gives a mixture of the corresponding alkylthiocyanates and alkylisothiocyanates which, unlike the underivatised analytes, are readily analysed by GC. On-column isomerisation is negligible. These lower alkyl derivatives are sufficiently volatile for static reaction headspace analysis, and detection limits obtained by electron impact MS are below 0.05 µg ml−1 with respect to the injection solution.
The product dissolved in the dry ether after washing with toluene. Using filtration sodium acetate was separated, and the filtrate was evaporated to obtain syrup and fractionated at a boiling point of 133-136 °C. The obtained product dissolved in hydrogen bromide of glacial acetic acid and this mixture reaction kept in an ice bath for 1hr. According to procedure, the product was methylated to obtain 1bromo-2, 3, 4, 6-tetramethylglucose.
The 1:1 hexane to ethyl acetate solvent resulted in the best separation because it not only showed extra spots that the other solvent mixtures did not have, but also the 4 spots were relatively dispersed with Rf values at 0.77, 0.56, 0.27, and 0.10 (Figure 2). Missing spots were also noted on the hexane only TLC plate. The orange eluent was ultimately chosen as our major product because it had significantly different TLC results than the 3 yellow eluents with the same Rf of 0.23 (Figure 3). The percent yield for this purification method was 248% and the extrapolated percent purified yield was around 135 %, which are both erroneously high. These high percent yield may be due to extra water weight or not fully evaporated
Acetylation Lab Summary Two versions of the same experiment were performed to assess the difference in reactivity of certain amines with acetic anhydride. Throughout both experiments, observations were made about the reaction progress. The starting materials and products were characterized using thin layer chromatography (TLC), infrared spectroscopy (IR), and melting point. During the first week, I dissolved 0.512g of aniline in 8.5mL of water, and added 5.5mL of 1M HLC. During this step, I observed that there were bubbles in the solution, especially at the bottom of the beaker.
ABSTRACT: Blackgram have the antioxidant properties because of the presence of the natural phenolic compounds which has beneficiary effects. In the present work, polyphenols are extracted using solid liquid extraction in a batch reactor at constant temperature. The polyphenol content is determined using the Folin- Ciocalteau method and expressed as Gallic Acid Equivalents (GAE). The effect of the solvents ethanol, methanol, acetone and water were studied on the parameters pH, extraction temperature and extraction time on Total Phenolic Content have been checked and it was optimized using a three variable, three-level Box-Behnken response surface methodology for extracting phenolic content. Validation of the model is based on the predicted
The catalyst surface acidity was determined by uisng the TGA/Pyridine sample. The acid strength of the catalyst was analyzed with potentiometric titration with n-butylamine in non-aqueous media. As represented in the Scheme 5, the Friedel-Crafts acylation of toluene was achieved with the prepared sulfated catalysts56 to investigate the catalytic activityA higher yields of the acylation products were obtained with sulfated tin oxide than Al3+-impregnated sulfated zirconia, since STO has greater acidity and higher acid strength. It was also observed that the sulfated tin oxide was found to show maximum higher acidity and higher efficiency for the acylation reaction when sulfate loading was 10 wt%. Among the structural characteristics, acidity and catalytic activity,a good relationship is
The three petroleum ether extracts were combined and concentrate to its minimum volume by using a stream of nitrogen. Analysis of fatty acids methyl ester (FAMEs) was carried out by Gas Chromatography using( Hewlett Packard, Palo Alto, CA, USA) (HP 6890) and(FID) detector was used at 250 °C . The fatty acid methyl siloxane capillary column HP – 5 (30m x 0.32 mm I.D. × 0.25 μm film thickness) was used. Nitrogen was used as the carrier gas (0.8 m / min gas flow).
To further explain how the concentration of acetone differs by parentage, I will explain how much g/l are contained with different percentages. The 5% contains 2.904g/l, the 10% contains 5.808g/l, the 20% contains 11.66g/l, the 30% contains 17.42g/l; we can see there is a positive relationship between percentage of concentration and g/l of acetone, (i.e. the higher the percentage, the more g/l is contained in solvent). The hypothesis states that the high concentration of acetone would be more effective and efficient in breaking down the phospholipids inside of the beet tissue. Up next was the null hypothesis for the experiment.
2007 Ram Tawakya Singh and Praveen Kumar Thakur have studied three types of binary mixture compared with its theoretical values which is based on nomto’s relation, van deal and vangeel additive mixture relations. o-cresol + acetophenone, o-cresol + ethyl acetate and o-cresol + methyl ethyl ketone mixtures reported the maximum value of molecular interaction around 0.53, 0.69 and 0.47 mole fractions of o-cresol. In o-cresol-acetophenone percentage deviations of velocity and interaction deviations of Rao's constant, Wada's constant and molar volume are both positive and negative. In o-cresol-ethyl acetate percentage deviations of velocity and interaction term α are found to positive only, where as the percentage deviations of Rao's constant, Wada's constant and molar volume are found to be negative. In o-cresol-methyl ethyl ketone percentage deviations of velocity and molecular interaction term are found to be positive, that of molar volume negative and that of Rao's constant and Wada's constant both positive and negative  Mehdi Hasana, Dinesh F. Shirudea, Apoorva P. Hiraya, Arun B. Sawant, and Ujjan B. Kadama, have
Jullok et al. (2011)  reported the pervaporative separation of acetic acid by a novel polyphenyl sulfone membrane For 90 wt% HAc, the separation factor was 8.4 for PPSU-27.5 and 5.7 for PPSU-30. Miyoshi et al. (1988)  carried out dehydration of an aqueous acetic acid solution through commercial ion-exchange membranes. Separation of water-acetic acid mixtures by using a blend membrane composed of poly (vinyl alcohol) and several hydrophilic copolymers such as poly (vinyl pyrrolidone) could achieve the separation factor of 34 with a flux of 140 g/m2-h at 25°C .