DR RAVINDRA S MUNNOLLI
@klsvdit.edu.in
Professor in Chemistry
KLS Vishwanathrao Deshpande Institute of Technology, Haliyal 581329
RESEARCH INTERESTS
polymer membrane science, biodiesel, biofuels,
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
M. Akki, D. S. Reddy, K. S. Katagi, A. Kumar, V. Babagond, R. S. Munnolli, and S. D. Joshi
Pleiades Publishing Ltd
Smita G. Mane, Dinesh S. Reddy, Kariyappa S. Katagi, Amit Kumar, Ravindra S. Munnolli, Nikhil S. Kadam, Mahesh C. Akki, H. Nagarajaiah, and Shrinivas D. Joshi
Elsevier BV
Kariyappa S. Katagi, Nikhil S. Kadam, Ravindra S. Munnolli, and Sangeeta D. Benni
Informa UK Limited
Sangeeta D Benni, Ravindra S Munnolli, Kariyappa S Katagi, Nikhil S Kadam, and Mahesh C Akki
Informa UK Limited
In the present research work, biodiesel is produced by in-situ technique using directly the dried seeds of Leonotis nepetifolia. Herein, methanol plays a dual role, as solvent for extraction of oil...
Kariyappa S. Katagi, Ravindra S. Munnolli, and Kallappa M. Hosamani
Elsevier BV
Tejraj M. Aminabhavi, Ravindra S. Munnolli, and J.Dale Ortego
Elsevier BV
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Walter de Gruyter GmbH
Sorption, diffusion and permeation of five esters into epichlorhydrin membrane have been studied in the temperature interval of 25° to 60°C by a sorption gravimetric method . A Fickian diffusion model was used to estimate the diffusion coefficients. The transport data were found to be dependent on the size of the penetrant molecules, their interactions with the chain segments of the polymer membrane, temperature of the experiment and, to some extent, on the penetrant concentration within the membrane material. The experimental results and the calculated parameters have been used to study the polymer-solvent interactions. None of the solvents used in this research has shown any degradative effects on the membrane used
T. M. Aminabhavi and R. S. Munnolli
Wiley
Results of a study on sorption and diffusion of chlorosulfonated polyethylene geomembrane with methyl benzoate, ethyl benzoate, methyl salicylate, iso-butyl salicylate, phenyl acetate, and diethyl phthalate in the temperature range 25–60°C are presented. A gravimetric sorption method is used to calculate the diffusion and permeation coefficients from the Fickian relationship. The diffusion results are dependent on penetrant–membrane interactions, temperature, and on penetrant concentration. The values of diffusion coefficients range from 0·02 × 10−7 cm2 s−1 for diethyl phthalate at 25°C to 1·81 × 10−7 cm2 s−1 for ethyl benzoate at 60°C. The activation energies for diffusion range from 21 to 50 kJ mol−1. The values of heat of sorption ranged between 2·2 and 6·4 kJ mol−1. Sorption results are also analyzed using a first-order sorption kinetic equation. Experimental results and calculated parameters are used to discuss the transport behavior. None of the esters used have shown any chemical attack toward the geomembrane.
Tejraj M. Aminabhavi, Ravindra S. Munnolli, and J. Dale Ortego
Wiley
Sorption and diffusion of n-alkanes into bromobutyl rubber membranes were investigated in the temperature interval 25-60 o C by a sorption gravimetric method. The Fickian diffusion equation was used to calculate the diffusion coefficients, which were dependent on the size of the alkanes, their interactions with the chain segments of the polymer and temperature. The diffusion coefficients varied from 0.34×10 -7 cm 2 /s (n-hexadecane) to 9.94×10 -7 cm 2 /s (n-hexane). The activation energy for diffusion varied from 14 kJ/mol (n-hexane) to 27 kJ/mol (n-hexadecane). Heat of sorption ranged from -1.4 kJ/mol for n-heptane to 2.0 kJ/mol for n-hexadecane. The sorption/swelling results are discussed in terms of first and second order kinetic equations. The molar mass between chain-entanglement-crosslinks was estimated from swelling data. The experimental and calculated results showed a systematic dependence on the increasing size of the alkanes. None of the solvents showed any degradative effects on the polymer
Tejraj M. Aminabhavi, Ravindra S. Munnolli, and J.Dale Ortego
Elsevier BV
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Informa UK Limited
Abstract Transport characteristics of aliphatic esters into Du Pont's VITON fluoropolymers have been investigated. Diffusion coefficients are calculated from the dimensional change measurements and are compared with those obtained from the weight-gain measurements. Effects of fluorine content of the polymers on the transport properties are discussed.
T. M. Aminabhavi and R. S. Munnolli
Wiley
The effect of different fluorine contents of DuPont VITON fluoropolymers and their transport characteristics in the presence of phenyl acetate, diethyl oxalate, diethyl malonate, diethyl succinate, acetone, methyl ethyl ketone and methyl iso-butyl ketone has been investigated over the temperature interval of 25−60°C. The average values of diffusion coefficients are obtained from the Fickian relation and the molecular transport is found to follow an anomalous behavior. Kinetic rate constants and pentration velocities are also calculated. The experimental results and the calculated quantities are studied in terms of polymer-solvent interactions.
On a etudie pour des temperatures comprises entre 25 et 60°C l'effet de differentes teneurs en fluor de fluoropolymeres VITON de DuPont de meme que leurs caracteristiques de transport en presence de phenyl acetate, de diethyl oxalate, de diethyl malonate, de diethyl succinate, d'acetone, de methylethyl cetone et de methyl iso-butyl cetone. Les valeurs moyennes des coefficients de diffusion ont ete obtenues avec la relation fickienne, et on a trouve que le transport moleculaire suivait un comportement anormal. Les constantes de vitesses cinetiques ont ete egalement ete calculees ainsi que les vitesses de penetration. Les resultats experimentaux et les quantites calculees sont etudies par rapport aux interactions polymeres-solvants.
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Wiley
Molecular transport as manifested by sorption and diffusion of organic esters into engineering polymer membranes, viz. nitrile butadiene rubber, styrene butadiene rubber, ethylene propylene diene terpolymer, neoprene and natural rubber, has been investigated in the temperature range 25–60°C by the sorption gravimetric technique. The sorption equilibrium for ethylene propylene diene terpolymer was lower than those of the other polymers with all the liquids. Diffusion and permeation coefficients were obtained for the polymer-solvent systems and these follow Arrhenius type behaviour in the temperature range investigated.
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Elsevier BV
Tejraj M. Aminabhavi, Ravindra S. Munnolli, William M. Stahl, and Subhas V. Gangal
Wiley
A sorption gravimetric technique has been used to estimate the diffusion and thermodynamic parameters of four different VITON fluoropolymers in the presence of five ester molecules. Diffusion parameters have been obtained by assuming the Fickian transport and their concentration dependencies are studied. Fluorine contents of the fluoropolymers have significant effects on the membrane transport characteristics. © 1993 John Wiley & Sons, Inc.
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Wiley
The results of the sorption and diffusion of aldehydes and ketones into structurally different elastomers such as ethylene propylene diene terpolymer, styrene butadiene rubber, nitrile butadiene rubber, neoprene and natural rubber are described in the temperature interval of 25-60°C. From these data, the Arrhenius parameters for the processes of diffusion and permeation are determined. The activation parameters for the diffusion of ketones range from 10.29 to 49.62 kJ/mol and for aldehydes, from 13.18 to 50.42 kJ/mol; these values fall in the range expected for rubbery polymers well above their glass transition temperatures. Transport data are affected by the nature of the interacting solvent molecule rather than its size and also by the structural variations of the elastomers. For all the solvents, the polymers remained intact; however, natural rubber in the presence of benzaldehyde showed degradative reactions at higher temperatures. Volumetric expansions of the elastomers have been measured from the dimensional response in the presence of aggressive solvents.
Tejraj M. Aminabhavi and Ravindra S. Munnolli
Informa UK Limited
Abstract The effects of different fluorine contents of the Du Pont VITON fluoropolymers have been studied in the presence of esters such as methyl acetoacetate, ethyl acetoacetate, methyl benzoate, ethyl benzoate, and 1-butyl acetate in the temperature interval of 25°–60°C. The sorption and diffusion of these liquids into the polymer membranes tend to deviate slightly from the Fickian mechanism; however, the diffusion data have been calculated from the Fickian model. It is suggested that the hindered chain segmental motion and the structural differences in the polymer membranes contribute to the overall sorption process, in addition to strictly thermodynamic considerations. The activation parameters for the transport processes have been estimated and the results are discussed in terms of the nature of polymer-solvent interactions.