Dielectric relaxation study of chlorobenzene with formamide at microwave frequency using time domain reflectometry

Pawar, V.P.; Mehrotra, S. C.

doi:10.1016/j.molliq.2003.12.018

Cited by 27 publications

(9 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If an even number of organic molecules is introduced, water forms semiclathrate‐like structures within which the organic rotates freely 58, 65. As a direct consequence, part of the void volume is lost (due to a contraction in the overall water network/structure) leading to negative values of $\overline {\nu}^{\rm E}$ and, at the same time, the number of effective dipoles decreases resulting in a negative ε E 64, 66. It follows that the position and extent of the minima (in terms of % mol water) are dependent on the nature of the organic component, where the lowest $\overline {\nu}$ E (Figure 8aII) occurs at higher water contents when increasing the alcohol chain length (methanol → n ‐propanol).…”

Section: Resultsmentioning

confidence: 99%

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃

Gómez‐Quero¹,

Cárdenas‐Lizana²,

Keane³

2009

AIChE Journal

View full text Add to dashboard Cite

Solvent effects in the liquid phase (0.1 MPa; 303 K) hydrodechlorination (HDC) of 2,4-dichlorophenol have been established over Pd/Al 2 O 3 . In the absence of secondary reactions, catalyst deactivation, and transport limitations, a stepwise HDC yields 2-chlorophenol and phenol, where product selectivity was insensitive to the nature of the solvent. In contrast, the initial HDC rates exhibited a marked dependence on the reaction medium and increased in the order: benzene \ THF \ n-hexane \ cyclohexane \ alcohols \ water. Higher rates result from the concomitant effect of an increase in the dielectric constant (e) and a decrease in the molar volume (m) of the solvent, where the major (ca. 80%) contribution is due to e. We attribute this response to the increased solvent capacity to stabilize the arenium intermediate at higher/lower e/v, an effect that extends to reaction in water þ organic combinations. We provide, for the first time, a reliable quantification of solvent effects that can be potentially applied to other catalytic hydrogenolysis systems. V

show abstract

Section: Resultsmentioning

confidence: 99%

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃

Gómez‐Quero¹,

Cárdenas‐Lizana²,

Keane³

2009

AIChE Journal

View full text Add to dashboard Cite

show abstract

“…As it follows from Figure 4, the " 1 value increases with increase in X for both DMSO and DESO. The information related to interaction of liquids A and B may be obtained by excess properties related to the permittivity and relaxation times in the mixture [15][16][17][18]. The excess permittivity " E is defined as:…”

Section: Resultsmentioning

confidence: 99%

Dielectric relaxation study of diethylsulfoxide/water mixtures

Markarian

Gabrielyan

2009

Physics and Chemistry of Liquids

View full text Add to dashboard Cite

Complex dielectric spectra of diethylsulfoxide (DESO)/water mixtures at 25 C over the entire concentration range of DESO, in the frequency range 0.2 / GHz 89 have been measured. In general, a description of the complex permittivity spectra requires a consideration of different types of relaxation processes depending upon DESO concentration. For the lower DESO concentration range the relaxation contribution to the spectrum is described by two Debye terms, whereas for higher concentration three Debye terms are used. For both at mol fraction equals to 0.9 and pure DESO as well Cole-Davidson type is valid. In addition, the data on the dimethylsulfoxide (DMSO)/water system obtained in this work well agree with those known from literature. The concentration dependent excess dielectric constant, excess inverse relaxation time and Kirkwood correlation factor of the mixtures have been determined.

show abstract

“…This significant deviation from unity in the ( ) values of the studied systems confirms that the effective dipoles in the mixture will be less than the corresponding average value in pure liquids and the clustering due to dipole-dipole interaction between the two hetero molecules. Modified forms of corrective correlation factor have been used to study the orientation of electric dipoles in binary mixture of anilines with 2-BE named as the effective Kirkwood correlation factor ( eff ) [24][25][26].…”

Section: Resultsmentioning

confidence: 99%

Dielectric Relaxation Studies of 2-Butoxyethanol with Aniline and Substituted Anilines Using Time Domain Reflectometry

Jeevanandham¹,

Kumar

Periyasamy

et al. 2014

Advances in Physical Chemistry

View full text Add to dashboard Cite

The complex dielectric spectra of 2-butoxyethanol with aniline and substituted anilines like aniline, o-chloroaniline, mchloroaniline, o-anisidine and m-anisidine binary mixtures in the composition of different volumes of percent (0%, 25%, 50%, 75%, and 100%) have been measured as a function of frequency between 10 MHz and 30 GHz at 298.15 K. The dielectric parameters like static dielectric constant ( 0 ) and relaxation time ( ) have been obtained by using least square fit method. By using these parameters ( 0 , ), effective Kirkwood correlation factor ( eff ), corrective Kirkwood correlation factor ( ), Bruggeman factor ( ), excess dielectric constant ( ), and excess inverse relaxation time (1/ ) values are calculated and discussed to yield information on the dipolar alignment and molecular rotation of the binary liquid mixtures. From all the derived dielectric parameters, molecular interactions are interpreted through hydrogen bonding.

show abstract

Dielectric relaxation study of chlorobenzene with formamide at microwave frequency using time domain reflectometry

Cited by 27 publications

References 15 publications

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃

Dielectric relaxation study of diethylsulfoxide/water mixtures

Dielectric Relaxation Studies of 2-Butoxyethanol with Aniline and Substituted Anilines Using Time Domain Reflectometry

Contact Info

Product

Resources

About

Dielectric relaxation study of chlorobenzene with formamide at microwave frequency using time domain reflectometry

Cited by 27 publications

References 15 publications

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al2O3

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al2O3

Dielectric relaxation study of diethylsulfoxide/water mixtures

Dielectric Relaxation Studies of 2-Butoxyethanol with Aniline and Substituted Anilines Using Time Domain Reflectometry

Contact Info

Product

Resources

About

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al₂O₃