Acid activated carbon derived from the pulp of Citrus limetta (mosambi) was employed as completel... more Acid activated carbon derived from the pulp of Citrus limetta (mosambi) was employed as completely biodegradable and highly economical adsorbent for the remediation of chromium(VI) from water. Prepared material was characterized by different techniques like PXRD, SEM, EDX and FTIR analysis. It was found that 0.1 g of activated carbon obtained from Citrus limetta was capable to almost completely adsorb hexavalent chromium (98.3 %) within 90 min at pH 2 and the adsorbent can efficiently be used up to five cycles simply by eluting with acid or alkali. Kinetic study showed that pseudo-2nd-order kinetic model gave the best fit while higher correlation factor was obtained with Freundlich isotherm model. Thermodynamic parameters confirmed endothermic and spontaneous nature of adsorption.
This study investigates the kinetics of oxidative conversion of benzyl and homobenzyl alcohols to... more This study investigates the kinetics of oxidative conversion of benzyl and homobenzyl alcohols to carbonyls using cerium(IV) sulfate in the presence of ruthenium(III) complex under mild acidic conditions. The results revealed that the low concentration of both alcohols and cerium(IV) ions drives the reaction to a first-order kinetics, whereas a higher concentration induces zero-order kinetics. In addition, the kinetics of the reaction were altered by the additives of hydrogen ions, cerium(III) ions, and chloride ions. We hope this study will be helpful in understanding the reaction kinetics of the oxidation of primary alcohols.
The complexes of Benzil-2, 4-dinitrophenyl hydrazone-p- bromo aniline with Ti(III),V(III), VO(IV)... more The complexes of Benzil-2, 4-dinitrophenyl hydrazone-p- bromo aniline with Ti(III),V(III), VO(IV),MoO (V), Fe(II), Fe(III) have synthesized and characterized by elemental analysis, magnetic measurement data, molar conductance, TGA,UV-visible and IR spectra data. The complexes of Ti (III), V (III), Fe (II) and Fe (III) have octahedral geometry while VO (IV) and MoO(V) have distorted octahedral geometry due to the presence of M=O moiety.
Interestingly IrCl3, which is considered to be a sluggish catalyst in alkaline media, was found t... more Interestingly IrCl3, which is considered to be a sluggish catalyst in alkaline media, was found to surpass the catalytic efficiency of even osmium and ruthenium in acidic media. Kinetic data, in iridium(III) chloride catalyzed oxidation of cyclopentanone and cycloheptanone by cerium(IV) perchlorate in aqueous perchloric acid medium, suggest the formation of complex C1 between cerium(IV) and organic substrate in the
Transition metals like osmium 1, iridium 2, tungsten 3, etc. have successfully been used as homog... more Transition metals like osmium 1, iridium 2, tungsten 3, etc. have successfully been used as homogeneous catalysts. Osmium is injurious in acidic medium; therefore, ruthenium 25 compounds were preferred and their catalytic activities were widely studied in acidic 2, 3 and alkaline 4, 5 media. The ...
Hydrate formation by cyclic ketones confirmed by kinetic and spectral studies shows reduction of ... more Hydrate formation by cyclic ketones confirmed by kinetic and spectral studies shows reduction of hexacyanoferrate(III) after the slow step. Orders and rate constants were confirmed by various methods.
In search of economical and effective catalysts it was found that IrCl3, a sluggish catalyst in a... more In search of economical and effective catalysts it was found that IrCl3, a sluggish catalyst in alkaline media, surpasses catalytic efficiency of osmium and ruthenium in aqueous perchloric acid medium in the oxidation of aliphatic ketones by ceric perchlorate. Rate decreases in the beginning at low acid concentrations, reaches to a minimum and then becomes proportional to [HClO4], probably due
... Oxidation of cyclic alcohols by cerium(IV) in acidic medium in the presence of iridium(III) c... more ... Oxidation of cyclic alcohols by cerium(IV) in acidic medium in the presence of iridium(III) chloride.Praveen K. Tandon Corresponding Author Contact Information , a , E-mail The Corresponding Author , Alok K. Singh 1 , a , Sumita Sahgal a and Santosh Kumar a. ...
... It has 4Correspondence to: Praveen K. Tandon, Department of Chemistry, University of Allahaba... more ... It has 4Correspondence to: Praveen K. Tandon, Department of Chemistry, University of Allahabad, Allahabad 211002, India. ... 5. Sosnovsky G. In Organic Peroxides, Vol. I, Swern D (ed.). Wiley Interscience: USA, 1970; 517560. 6. Biella S, Prati L, Rossi M. J. Mol. Catal. ...
Acid activated carbon derived from the pulp of Citrus limetta (mosambi) was employed as completel... more Acid activated carbon derived from the pulp of Citrus limetta (mosambi) was employed as completely biodegradable and highly economical adsorbent for the remediation of chromium(VI) from water. Prepared material was characterized by different techniques like PXRD, SEM, EDX and FTIR analysis. It was found that 0.1 g of activated carbon obtained from Citrus limetta was capable to almost completely adsorb hexavalent chromium (98.3 %) within 90 min at pH 2 and the adsorbent can efficiently be used up to five cycles simply by eluting with acid or alkali. Kinetic study showed that pseudo-2nd-order kinetic model gave the best fit while higher correlation factor was obtained with Freundlich isotherm model. Thermodynamic parameters confirmed endothermic and spontaneous nature of adsorption.
This study investigates the kinetics of oxidative conversion of benzyl and homobenzyl alcohols to... more This study investigates the kinetics of oxidative conversion of benzyl and homobenzyl alcohols to carbonyls using cerium(IV) sulfate in the presence of ruthenium(III) complex under mild acidic conditions. The results revealed that the low concentration of both alcohols and cerium(IV) ions drives the reaction to a first-order kinetics, whereas a higher concentration induces zero-order kinetics. In addition, the kinetics of the reaction were altered by the additives of hydrogen ions, cerium(III) ions, and chloride ions. We hope this study will be helpful in understanding the reaction kinetics of the oxidation of primary alcohols.
The complexes of Benzil-2, 4-dinitrophenyl hydrazone-p- bromo aniline with Ti(III),V(III), VO(IV)... more The complexes of Benzil-2, 4-dinitrophenyl hydrazone-p- bromo aniline with Ti(III),V(III), VO(IV),MoO (V), Fe(II), Fe(III) have synthesized and characterized by elemental analysis, magnetic measurement data, molar conductance, TGA,UV-visible and IR spectra data. The complexes of Ti (III), V (III), Fe (II) and Fe (III) have octahedral geometry while VO (IV) and MoO(V) have distorted octahedral geometry due to the presence of M=O moiety.
Interestingly IrCl3, which is considered to be a sluggish catalyst in alkaline media, was found t... more Interestingly IrCl3, which is considered to be a sluggish catalyst in alkaline media, was found to surpass the catalytic efficiency of even osmium and ruthenium in acidic media. Kinetic data, in iridium(III) chloride catalyzed oxidation of cyclopentanone and cycloheptanone by cerium(IV) perchlorate in aqueous perchloric acid medium, suggest the formation of complex C1 between cerium(IV) and organic substrate in the
Transition metals like osmium 1, iridium 2, tungsten 3, etc. have successfully been used as homog... more Transition metals like osmium 1, iridium 2, tungsten 3, etc. have successfully been used as homogeneous catalysts. Osmium is injurious in acidic medium; therefore, ruthenium 25 compounds were preferred and their catalytic activities were widely studied in acidic 2, 3 and alkaline 4, 5 media. The ...
Hydrate formation by cyclic ketones confirmed by kinetic and spectral studies shows reduction of ... more Hydrate formation by cyclic ketones confirmed by kinetic and spectral studies shows reduction of hexacyanoferrate(III) after the slow step. Orders and rate constants were confirmed by various methods.
In search of economical and effective catalysts it was found that IrCl3, a sluggish catalyst in a... more In search of economical and effective catalysts it was found that IrCl3, a sluggish catalyst in alkaline media, surpasses catalytic efficiency of osmium and ruthenium in aqueous perchloric acid medium in the oxidation of aliphatic ketones by ceric perchlorate. Rate decreases in the beginning at low acid concentrations, reaches to a minimum and then becomes proportional to [HClO4], probably due
... Oxidation of cyclic alcohols by cerium(IV) in acidic medium in the presence of iridium(III) c... more ... Oxidation of cyclic alcohols by cerium(IV) in acidic medium in the presence of iridium(III) chloride.Praveen K. Tandon Corresponding Author Contact Information , a , E-mail The Corresponding Author , Alok K. Singh 1 , a , Sumita Sahgal a and Santosh Kumar a. ...
... It has 4Correspondence to: Praveen K. Tandon, Department of Chemistry, University of Allahaba... more ... It has 4Correspondence to: Praveen K. Tandon, Department of Chemistry, University of Allahabad, Allahabad 211002, India. ... 5. Sosnovsky G. In Organic Peroxides, Vol. I, Swern D (ed.). Wiley Interscience: USA, 1970; 517560. 6. Biella S, Prati L, Rossi M. J. Mol. Catal. ...
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