416,270 research outputs found
Esterification of Acetic Acid with Butanol: Operation in a Packed Bed Reactive Distillation Column
The esterification reaction between acetic acid and butanol was investigated in a reactive distillation column. The thermodynamic aspects of considered system are discussed, equilibrium constant, vapor pressures and UNIQUAC interaction parameters were investigated. Reactive distillation experiments were carried out to provide high purity butyl acetate. For this purpose, a 2 m column with nonreactive and reactive zones filled with Amberlyst 15 and Raschig rings, were used in the experiments. Several operating conditions such as total feed flow rate, molar ratio of butanol to acetic acid, amount of catalyst and reboiler temperature and three different column configurations were realized experimentally.
The experimental optimum values of these parameters obtained were 1.6 mol h–1, 1, 25 g and 383 K, respectively within the range of study. The butyl acetate purity of 82 % and acetic acid conversion of 80.5 % were obtained at the optimum operating conditions
Antioxidant Capacity Of Frangipani (Plumeria Alba) Powder Extract
This research aimed to identify the antioxidant capacity, vitamin C (ascorbic acid), and total phenolic compounds of frangipani flower powder. The powder was extracted using ethanol, methanol, acetic acid, and water (aquadest). Antioxidant capacity of each extract were determined using 2,2-diphenyl-1-picrylhydrazyl radical scavenging method, vitamin C were determined using 2,4 Dinitrophenylhydrazine, and total phenolic compounds were determined using Folin Ciocalteu reagent. All of parameters were measured by spectrofotometer. The result shows that the highest value of antioxidant capacity was ethanolic extract (18.19%) and the lowest value was acetic acid extract (12.74%). The highest value of vitamin C was aqueous extract (3.49 mg/100g) and the lowest value was acetic acid extract (3.02 mg/100g). The highest value of total phenolic content was aqueous extract (25.49 mg GAE/g) and the lowest value was acetic acid extract (22.74 mg GAE/g). In conclusion, the higher antioxidant capacity was not always followed by the higher of vitamin C and total phenolic compounds
Acetylene terminated aspartimides and resins therefrom
Acetylene terminated aspartimides are prepared using two methods. In the first, an amino-substituted aromatic acetylene is reacted with an aromatic bismaleimide in a solvent of glacial acetic acid and/or m-cresol. In the second method, an aromatic diamine is reacted with an ethynyl containing maleimide, such an N-(3-ethynyl phenyl) maleimide, in a solvent of glacial acetic acid and/or m-cresol. In addition, acetylene terminated aspartimides are blended with various acetylene terminated oligomers and polymers to yield composite materials exhibiting improved mechanical properties
Trap Response of Michigan Social Wasps (Hymenoptera: Vespidae) to the Feeding Attractants Acetic Acid, Isobutanol, and Heptyl Butyrate.
Nine species of social wasps were captured in traps baited with acetic acid, isobutanol, heptyl butyrate and combinations of acetic acid and either isobutanol or heptyl butyrate. Three yellowjacket species in the Vespula rufa species group were captured in traps (Vespula acadica (Sladen), Vespula consobrina (Saussure), Vespula vidua (Saussure)). They responded similarly, with attraction only to heptyl butyrate. Three yellowjacket species in the Vespula vulgaris species group were also captured in traps (Vespula vulgaris (L.), Vespula flavorpilosa Jacobson, Vespula maculifrons (Buyyson)). They responded similarly, with attraction primarily to the combination of acetic acid and isobutanol. The bald-faced hornet, Dolichovespula maculata (L.), was attracted to acetic acid and was more strongly attracted to the combination of acetic acid and isobutanol. The aerial yellowjacket, Dolichovespula arenaria (Fabr.), was attracted to isobutanol, and was more strongly attracted to the combination of acetic acid and isobutanol. These results add to our understanding of how to target various species of social wasps with chemical lures
Effects of Pitfall Trap Preservative on Collections of Carabid Beetles (Coleoptera: Carabidae)
Effects of six pitfall trap preservatives (5% acetic acid solution, distilled water, 70% ethanol, 50% ethylene glycol solution, 50% propylene glycol solution, and 10% saline solution) on collections of carabid beetles (Coleoptera: Carabidae) were studied in a west-central Illinois deciduous forest from May to October 2005. A total of 819 carabids, representing 33 species and 19 genera, were collected. Saline produced significantly fewer captures than did acetic acid, ethanol, ethylene glycol, and propylene glycol, while distilled water produced significantly fewer captures than did acetic acid. Significant associations between numbers of captures and treatment were seen in four species: Amphasia interstitialis (Say), Calathus opaculus LeConte, Chlaenius nemoralis Say, and Cyclotrachelus sodalis (LeConte). Results of this study suggest that type of preservative used can have substantial effects on abundance and species composition of carabids collected in pitfall traps
Recycling of waste engine oils using a new washing agent
This paper addresses recycling of waste engine oils treated using acetic acid. A recycling process was developed which eventually led to comparable results with some of the conventional methods. This gives the recycled oil the potential to be reused in cars' engines after adding the required additives. The advantage of using the acetic acid is that it does not react or only reacts slightly with base oils. The recycling process takes place at room temperature. It has been shown that base oils and oils' additives are slightly affected by the acetic acid. Upon adding 0.8 vol% of acetic acid to the used oil, two layers were separated, a transparent dark red colored oil and a black dark sludge at the bottom of the container. The base oils resulting from other recycling methods were compared to the results of this paper. The comparison showed that the recycled oil produced by acetic acid treatment is comparable to those recycled by the other conventional methods
Response surface methodology approach to study the influence of PEG and water in cellulose acetate dialysis membranes
Flat sheet asymmetric dialysis membranes were fabricated using phase inversion method from polymer solution consisting of cellulose acetate, acetic acid, polyethylene glycol (PEG) and distilled water. The effect of acetic acid/PEG ratio and the distilled water content in the dialysis membrane were being investigated with respect to the urea clearance performance. Response surface methodology (RSM) was used to design the experiments and analysed the results obtained. The analysis revealed that the significant factor that affects the cellulose acetate dialysis membrane performance in terms of urea clearance is the ratio of acetic acid/PEG. Dialysis membrane with higher ratio of acetic acid/PEG gives higher urea clearance percentage due to the formation of finger like macrovoids. The relation between the urea clearance and the ratio of acetic acid/PEG in the given range of 4 – 14, was a quadratic model and the mathematical model suggested could adequately describe the performance indicators within the limits mentioned
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