Excess volumes and excess enthalpies of acetic and its methyl-substituted acids + acetonitrile

1985 ◽  
Vol 63 (11) ◽  
pp. 3269-3275 ◽  
Author(s):  
B. S. Lark ◽  
T. S. Banipal
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Concentration Dependence ◽  
Steric Hindrance ◽  
Isobutyric Acid ◽  
Excess Volumes ◽  
Excess Enthalpies ◽  
Dilatometric Method ◽  
Dipole Interactions

Excess volumes of the systems acetonitrile (ACN) + acetic acid (AA), + propionic acid (PA) and + isobutyric acid (IBA) at 298.15 and 308.15 K and + trimethylacetic acid (TMA) at 313.15 K have been measured using dilatometric method. The observed values are found to be negative for the first three systems while the last system has sigmoid concentration dependence. Excess enthalpies for the first three systems at 308.15 K and for the last system at 313.15 K have also been determined and found to be positive. The results have been explained in terms of depolymerization of the acids, dipole–dipole interactions between heteromolecules and the steric hindrance caused by the increasing methylation.

Excess Gibbs energy for binary mixtures of acetonitrile with acetic acid, propionic acid, isobutyric acid, and trimethylacetic acid

1991 ◽  
Vol 69 (12) ◽  
pp. 2117-2121 ◽  
Author(s):  
T. S. Banipal ◽  
B. S. Lark ◽  
S. Singh
Keyword(s):  
Acetic Acid ◽  
Gibbs Energy ◽  
Carboxylic Acids ◽  
Propionic Acid ◽  
Binary Mixtures ◽  
Activity Coefficients ◽  
Excess Gibbs Energy ◽  
Composition Range ◽  
Isobutyric Acid ◽  
Dimerization Constant

Total vapour pressures for binary mixtures containing acetic acid, propionic acid, isobutyric acid, and trimethylacetic acid with acetonitrile have been measured for the entire composition range at 298.15 and 318.15 K using a static manometric method. All systems show positive deviations from Raoult's law, enhanced by both an increase in temperature and an increase in the methylation of acetic acid. Activity coefficients have been calculated by taking into consideration the dimerization of these carboxylic acids in the vapour phase. TSE values obtained from GE and earlier reported HE values are found to be negative for acetic acid, about zero for propionic and isobutyric acids, and positive for trimethylacetic acid for the whole composition range. The results have been interpreted in terms of various contributions such as depolymerization, heteromolecular dipole–dipole interactions, and the increasing dimerization constant and steric hindrance with increase of complexity of the acid. Key words: excess Gibbs energy, carboxylic acids, acetonitrile, activity coefficients

Pycnometric determination of densities and excess volumes of binary mixtures containing at least one associating component

1990 ◽  
Vol 55 (10) ◽  
pp. 2395-2403 ◽  
Author(s):  
Kamila Chýlková ◽  
Ivona Malijevská
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Binary Mixtures ◽  
Trifluoroacetic Acid ◽  
Excess Volume ◽  
Excess Volumes ◽  
Molar Excess ◽  
Molar Excess Volumes

Densities at 20 °C and molar excess volumes calculated from them are reported in the work for the mixtures of the substances: propionic acid-n-heptane, propionic acid-benzene, trifluoroacetic acid-benzene, propionic acid-cyclohexane, acetic acid-cyclohexane, acetic acid-trifluoroacetic acid, acetic acid-propionic acid, and propionic acid-trifluoroacetic acid. For the last system mentioned, a strange dependence of excess volume on composition was found which is noted for three local extremes. The dependences of excess volume on composition are correlated by the Redlich-Kister polynomial.

scholarly journals The Densities and Compression Isotherms of Formic Acid-, Acetic Acid-, Propionic Acid-, and Isobutyric Acid-Water Mixtures.

1971 ◽  
Vol 25 ◽  
pp. 2852-2864 ◽  
Author(s):  
Jaakko Korpela ◽  
Kjell Haugsten ◽  
Svend Erik Rasmussen ◽  
Sigfrid Svensson ◽  
J. Koskikallio ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Propionic Acid ◽  
Isobutyric Acid ◽  
Acid Water ◽  
Compression Isotherms

Excess molar volumes of binary mixtures of acetic acid and propionic acid with some members of homologous series of alkanes

1991 ◽  
Vol 56 (4) ◽  
pp. 736-744 ◽  
Author(s):  
Ondřej Drábek ◽  
Ivan Cibulka
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Alkyl Chain ◽  
Excess Molar Volumes ◽  
Liquid Mixtures ◽  
Entire Concentration Range ◽  
Molar Volumes ◽  
Binary Liquid ◽  
Alkane Molecule ◽  
Increasing Temperature

Excess molar volumes of binary liquid mixtures of (acetic or propionic acid = hexane) at 25 and 35°C, and (acetic or propionic acid + heptane or octane) and (acetic acid + dodecane) at 25°C, measured with a tilting dilution dilatometer, are reported. The excess volumes are positive over the entire concentration range for all mixtures and increase with increasing length of an alkane molecule, decrease with increasing of the alkyl chain in a molecule of carboxylic acid, and increase with increasing temperature.

Vapour-liquid equilibrium in the ternary system cyclohexane-acetic acid-propionic acid

1989 ◽  
Vol 54 (11) ◽  
pp. 2840-2847 ◽  
Author(s):  
Ivona Malijevská ◽  
Alena Maštalková ◽  
Marie Sýsová
Keyword(s):  
Acetic Acid ◽  
Ternary System ◽  
Propionic Acid ◽  
Activity Coefficients ◽  
Error Propagation ◽  
Analytical Techniques ◽  
Liquid Equilibrium ◽  
Consistency Test ◽  
Propagation Law ◽  
Equilibrium Data

Isobaric equilibrium data (P = 101.3 kPa) for the system cyclohexane-acetic acid-propionic acid have been measured by two different analytical techniques. Activity coefficients calculated by simultaneous solving of equations for the chemical and phase equilibria were subjected to a consistency test based on inaccuracies determined from the error propagation law, and were correlated by Wilson’s equation. The activity coefficients measured were compared with those calculated from binary vapour-liquid equilibrium data and with values predicted by the UNIFAC method.

Excess enthalpies and excess volumes for (butane + butan-1-ol) at the temperatures (298.15, 323.15, and 348.15) K and pressures (5, 10, and 15) MPa

1994 ◽  
Vol 26 (12) ◽  
pp. 1275-1286 ◽  
Author(s):  
J.T. Sipowska ◽  
L.R. Lemon ◽  
J.B. Ott ◽  
P.R. Brown ◽  
B.G. Marchant
Keyword(s):  
Excess Volumes ◽  
Excess Enthalpies

scholarly journals Pilot Study of the Effects of Polyphenols from Chestnut Involucre on Methane Production, Volatile Fatty Acids, and Ammonia Concentration during In Vitro Rumen Fermentation

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 108
Author(s):  
Yichong Wang ◽  
Sijiong Yu ◽  
Yang Li ◽  
Shuang Zhang ◽  
Xiaolong Qi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Propionic Acid ◽  
Acid Content ◽  
Volatile Fatty Acids ◽  
Rumen Fermentation ◽  
Gas Production ◽  
Quadratic Response ◽  
In Vitro Rumen Fermentation

Nutritional strategies can be employed to mitigate greenhouse emissions from ruminants. This article investigates the effects of polyphenols extracted from the involucres of Castanea mollissima Blume (PICB) on in vitro rumen fermentation. Three healthy Angus bulls (350 ± 50 kg), with permanent rumen fistula, were used as the donors of rumen fluids. A basic diet was supplemented with five doses of PICB (0%–0.5% dry matter (DM)), replicated thrice for each dose. Volatile fatty acids (VFAs), ammonia nitrogen concentration (NH3-N), and methane (CH4) yield were measured after 24 h of in vitro fermentation, and gas production was monitored for 96 h. The trial was carried out over three runs. The results showed that the addition of PICB significantly reduced NH3-N (p < 0.05) compared to control. The 0.1%–0.4% PICB significantly decreased acetic acid content (p < 0.05). Addition of 0.2% and 0.3% PICB significantly increased the propionic acid content (p < 0.05) and reduced the acetic acid/propionic acid ratio, CH4 content, and yield (p < 0.05). A highly significant quadratic response was shown, with increasing PICB levels for all the parameters abovementioned (p < 0.01). The increases in PICB concentration resulted in a highly significant linear and quadratic response by 96-h dynamic fermentation parameters (p < 0.01). Our results indicate that 0.2% PICB had the best effect on in-vitro rumen fermentation efficiency and reduced greenhouse gas production.

scholarly journals Effects of the Forage Type and Chop Length of Ramie Silage on the Composition of Ruminal Microbiota in Black Goats

Animals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 177
Author(s):  
Shengnan Sun ◽  
Zhenping Hou ◽  
Qiuzhong Dai ◽  
Duanqin Wu
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Relative Proportion ◽  
Corn Silage ◽  
Rumen Ph ◽  
Silage Fermentation ◽  
Fermentation Quality ◽  
Ruminal Microbiota ◽  
Forage Type ◽  
Optimal Quality

The aim of this study was to investigate the effects of the forage type and chop length of ramie (Boehmeria nivea (L.) Gaud.) silage on rumen fermentation and ruminal microbiota in black goats. Sixteen Liuyang black goats (22.35 ± 2.16 kg) were fed with the roughage of corn silage or ramie silage at chop lengths of 1, 2, or 3 cm. The Chao 1 index and the observed number of microbial species differed significantly between the corn and ramie silage groups (p < 0.05); however, Firmicutes (relative proportion: 34.99–56.68%), Bacteroidetes (27.41–47.73%), and Proteobacteria (1.44–3.92%) were the predominant phyla in both groups. The relative abundance of Verrucomicrobia (0.32–0.82%) was lowest for the 2 and 3 cm chop lengths (p < 0.05) and was negatively correlated with rumen pH and propionic acid concentration (p < 0.05), but positively correlated with the ratio of acetic acid to propionic acid (p < 0.05). The ramie silage fermentation quality was highest for the 1 cm chop length, suggesting that moderate chopping produces optimal quality silage.

Factors limiting the intake of feed by sheep. I. The significance of palatability, the capacity of the alimentary tract to handle digesta, and the supply of glucogenic substrate.

1966 ◽  
Vol 17 (6) ◽  
pp. 939 ◽  
Author(s):  
RH Weston
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Polyvinyl Chloride ◽  
Dry Matter ◽  
Alimentary Tract ◽  
Control Period ◽  
Feed Consumption ◽  
Ad Libitum

Voluntary feed consumption (VFC) decreased when a quantity of the diet being consumed by the sheep was introduced into the rumen. On diets of lucerne hay, lucerne hay plus maize, wheaten hay, and wheaten straw, the decreases in VFC ranged from 90 to 110% of the quantity introduced intraruminally when this quantity varied from 20 to 60% of the VFC during control periods. When sheep consumed wheaten straw ad libitum, and a quantity of coarsely ground wheaten straw equal to 140% of the VFC during a control period was given intraruminally, VFC ceased and digesta accumulated in the rumen. VFC decreased when indigestible materials were introduced into the rumen. The voluntary consumption of lucerne hay decreased by 15% when sawdust was introduced into the rumen at a rate equivalent by weight to 17% of the VFC during a control period ; decreases of 7 and 9% were found when finely ground polyvinyl chloride was introduced at rates equivalent by weight to 25 and 50% respectively of VFC during control periods. The voluntary consumption of wheaten hay decreased by 16 and 19% when sawdust was introduced into the rumen at rates equivalent by weight to 25 and 18% respectively of VFC during control periods. Intraruminal infusions of acetic acid, propionic acid, or a mixture of acetic, propionic, and butyric acids providing 290–510 kcal of energy daily were accompanied by decreases in the voluntary consumption of lucerne hay and wheaten hay; the decreases ranged from 0.29 to 0.86 g dry matter per kcal of energy infused; similar decreases were obtained when propionic acid was infused into the abomasum of sheep given lucerne hay. The intake of lucerne hay was 9% higher when given alone than when supplemented with 6% propionic acid. The results are discussed in relation to factors limiting the intake of lucerne hay and wheaten hay.

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