Indian Journal of Chemistry

Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical

http://www.niscair.res.in; http://nopr.niscair.res.in

Total visitors: 2146 since 3-6-2014

CODEN: ICACEC; ISSN: 0376-4710 (Print), 0975-0975 (Online)

 

 

 

 

 

VOLUME 53A

NUMBER 6

JUNE 2014

 

CONTENTS

 

 

659

 

Theoretical investigation of the cyclic reaction of NO2 with CO mediated by ScO+

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Jianhui Zhang*, Yanli Leng, Yongcheng Wang &
Pan Chen

 

 

 

Mechanism of the reaction of NO2(2A1) with CO(1Σ+), mediated by ScO+ on triplet and singlet electronic states has been investigated. TOFs of the reaction are found to be 1.2×109 s-1 and 7.0×10-25 s-1 at 298 K for the triplet and singlet electronic states respectively. In comparison with 1ScO+, 3ScO+ has better catalytic function for the title reaction at the 298 K.

 

 

 

 

 

 

665

 

Preparation, characterization and photocatalytic activity of cerium-doped titanium dioxide supported on activated carbon fiber composite

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Shuhua Yao, Yue Yang, Shuangping Song & Zhongliang Shi*

 

 

 

Higher degradation of methyl orange has been achieved with cerium-doped titanium dioxide supported on activated carbon fibers. The 0.20 mol% Ce-doped catalyst shows the highest photocatalytic activity.

 

 

 

 

 

672

 

UV-A/solar light induced Fenton mineralization of Acid Red 1 using Fe modified bentonite composite

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I Muthuvel, B Krishnakumar & M Swaminathan*

 

 

 

A novel heterogeneous bentonite based Fenton catalyst has been synthesized by solid state dispersion method and used for the degradation of Acid Red 1 dye under both UV and solar light. The catalyst was found to be stable, reusable and efficient over a wide pH range of 2–7. Though the dye degradation is 100% degradation at the optimum pH 3, it is also significant at pH 7 (69% under UV and 84% under solar light).

 

 

 

 

 

679

 

Synthesis of self-assembly of agarose-fatty acid ester nanoparticles

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Stalin Kondaveeti, Dharmesh R Chejara &
A K Siddhanta
*

 

 

 

Microwave assisted facile synthesis and characterization of hydrophobically modified nanoparticulate agarose esters of stearic/palmitic acids, capable of forming self-assembly is  described. DLS and TEM show the formation of 4–5 nm micelles and 220–250 nm polymeric vesicles in these new agarose based nanosize materials.

 

 

 

 

 

 

688

 

Ultrasonic investigation on segmental motion of some polymers in solution

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V Kannappan*, B S Santhi &
D Reuban Jonathan

 

 

 

The temperature of onset of segmental motion determined in some poly(amide ester)s in solution by a novel ultrasonic method is comparable to the glass transition temperatures determined for the solid samples by differential calorimetric method.

 

 

 

Notes

 

695

 

Preparation, characterization and study of
transport of organic hydrocarbon vapours through EVA-organo modified Cloisite®15A nanocomposites

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

N S Suja , C Jisha, S Vishnu Sankar & Anil Kumar S*

 

 

 

Nanocomposite membranes based on poly(ethylene-co-vinyl acetate) copolymer (18% vinyl acetate) and organo modified
clay have been prepared by mechanical mixing by two roll mill method with dicumyl peroxide as the cross linking agent.
The platelet-like morphology of sillicates increases the
tortuosity of path of solvent molecules through the nanofilled polymer samples.

 

 

 

 

700

 

Kinetics, thermodynamics and ion exchange characteristics of thorium phosphate: An inorganic ion exchanger

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tarun Parangi, Bina Wani & Uma Chudasama*

 

 

 

Thorium phosphate, a cation exchanger synthesized by sol-gel method, exhibits promising ion exchange characteristics. Efficient metal ion separations carried out with this material indicates its high potential for use as a cation exchanger.

 

 

 

 

 

Authors for correspondence are indicated by (*)

 

 

 

Indian Journal of Chemistry

Vol. 53A, June 2014, pp. 659-664

 

 

Theoretical investigations of the cyclic reaction of NO2
with CO mediated by ScO+

Jianhui Zhanga,*, Yanli Lenga, Yongcheng Wangb & Pan Chena

aDepartment of Metallurgical Engineering, Lanzhou Resources & Environment Voc-Tech College, Lanzhou, 730 021, China

Email: gszhangjh@126.com

bCollege of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, 730 070, China

Received 5 November 2013; revised and accepted 1 May 2014

Studies based on B3LYP and CCSD(T) have been carried out to investigate the mechanism of the reaction NO2(2A1) with CO(1Σ+) mediated by ScO+ on triplet and singlet electronic states. The natural population analysis and the frontier molecular orbitals analysis have also been used to discuss the structure of reactant-complexes. The O-atom affinities have been used to indicate the O transfer between NO2 and CO, mediated by ScO+. Finally, the energetic span model proposed by Kozuch has been applied to investigate the TOF-determining transition state and TOF-determining intermediate. The TOFs of the reaction NO2(2A1) with CO(1Σ+) mediated by ScO+ on triplet and singlet electronic states are found to be 1.2×109 s-1 and 7.0×10-25 s-1 at 298 K respectively by the AUTOF program. In comparison with 1ScO+, 3ScO+ has better catalytic function for the title reaction at the 298 K.

Keywords: Theoretical chemistry, Cyclic reactions, Electronic states, Reaction mechanisms, Kinetics,
Turnover frequency, Nitrogen dioxide, Carbon monoxide

 

Indian Journal of Chemistry

Vol. 53A, June 2014, pp. 665-671

 

 

Preparation, characterization and photocatalytic activity of cerium-doped
titanium dioxide supported on activated carbon fiber composite

Shuhua Yao, Yue Yang, Shuangping Song & Zhongliang Shi*

School of Applied Chemistry, Shenyang University of Chemical Technology, Shenyang 110142, China

Email: shzhl2000@163.com

Received 29 October 2013; revised and accepted 22 April 2014

A visible light-driven photocatalyst, viz., Ce/TiO2/ACF, has been prepared by supporting the photoactive cerium-doped titanium dioxide on activated carbon fibers via hydrolysis of tetrabutyl titanate with ammonium ceric nitrate in the presence of activated carbon fibers. TiO2 is used for photocatalysis while the activated carbon fibers is used for separation and the doped cerium is used to enhance the photocatalytic activity of titanium dioxide. The prepared photocatalysts have been characterized by BET surface area, scanning electron microscopy, X-ray diffraction and UV-vis absorption spectroscopy. The effect of cerium-doped content on the photocatalytic activity has been studied and 0.2 mol% Ce/TiO2/ACF is found to exhibit the highest photoactivity. The photocatalytic activities of the obtained photocatalysts under UV and visible light have been estimated by measuring the degradation rate of methylene orange in aqueous solution. Results show that the prepared photocatalyst is activated by visible light and may be used as effective catalyst in photooxidation reactions. In addition, the recyclability of the prepared photocatalyst is also confirmed since the Ce/TiO2/ACF retains ca. 86.5% of its activity after being used four times. The photocatalyst, therefore, may be potentially applied for the treatment of water contaminated by organic pollutants.

Keywords: Photocatalysts, Supported catalysts, Doped catalysts, Cerium doping, Dye degradation,
Titanium dioxide, Activated carbon fiber composites

 

 

Indian Journal of Chemistry

Vol 53A, June 2014, pp. 672-678

 

 

UV-A/solar light induced Fenton mineralization of Acid Red 1 using
Fe
modified bentonite composite

I Muthuvel, B Krishnakumar & M Swaminathan*

Photocatalysis Laboratory, Department of Chemistry, Annamalai University, Annamalainagar 608 002, India

Email: chemres50@gmail.com

Received 1 January 2014; revised and accepted 21 May 2014

A novel heterogeneous bentonite based Fenton (Fe-B) catalyst has been synthesized by solid state dispersion method and characterized by inductively coupled plasma atomic emission spectrometer, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy images, diffuse reflectance spectra and Brunauer-Emmett-Teller surface area measurements. The Fe-B catalyst has been applied for the degradation of Acid Red 1 dye using both UV and solar light. The effects of various parameters such as pH, H2O2 dosage, Fe dosage on degradation performance were evaluated. The catalyst was found to be stable, reusable and efficient over a wide pH range of 2–7. Mineralization of dye was confirmed by COD measurements.

Keywords: Catalysts, Photocatalysts, Solid state dispersion, Dye degradation, Photodegradation,
Hetero-Fenton degradation
, Acid Red 1, Bentonite clay, Wastewater treatment

 

Indian Journal of Chemistry

Vol. 53A, June 2014, pp. 679-687

 

 

Synthesis of self-assembly of agarose-fatty acid ester nanoparticles

Stalin Kondaveetia, Dharmesh R Chejaraa, b, A K Siddhantaa, b, *

aMarine Biotechnology and Ecology Discipline, CSIR-Central Salt & Marine Chemicals Research Institute,

G B Marg, Bhavnagar 364 002, Gujarat, India

bAcademy of Scientific & Innovative Research, Anusandhan Bhavan,

2 Rafi Marg, New Delhi 110 001, India

Email: aks@csmcri.org

Received 24 December 2013, revised and accepted 23 March 2014

Microwave assisted facile synthesis of hydrophobically modified nano-sized particulate esters of agarose and stearic and palmitic acids (Ag-SA and Ag-PA), employing carbodiimide chemistry has been described. The hydrophobically modified agarose is capable of forming self-assembled nano-sized particles. Physicochemical characterization of Ag-SA, Ag-PA has been carried out by gel permeation chromatography, differential scanning calorimetric, scanning electron microscopy and FT-IR, 13C-NMR and 1H-NMR spectra. The aqueous self-assembly of the modified polymer has been studied by dynamic light scattering and transmission electron microscopy, which shows the formation of 4-5 nm micelles, and 220-250 nm polymeric vesicles. TEM images demonstrate that the self-aggregate is spherical in shape. These new agarose based nano-sized materials may be of potential utility in biomedical applications as drug delivery vehicles.

Keywords: Nanoparticles, Self-assembly, Hydrophobization, Natural polymers, Polysaccharides, Carbodiimides, Agarose, Fatty acid esters, Stearic acid, Palmitic acid, Microwave synthesis

 

 

 

 

 

Indian Journal of Chemistry

Vol. 53A, June 2014, pp. 688-694

 

Ultrasonic investigation on segmental motion of some
polymers in solution

V Kannappan*, B S Santhi & D Reuban Jonathan

Post Graduate & Research Department of Chemistry, Presidency College, Chennai 600 005, India

Email: vkannappan48@gmail.com

Received 17 December 2013; revised and accepted 6 May 2014

A novel method involving ultrasonic velocity measurement has been adopted to determine temperature of onset of segmental motion in some poly (amide ester)s in solution. Acoustical parameters such as adiabatic compressibility, free length, internal pressure, fractional free volume, coefficient of thermal expansion, coefficient of adiabatic compressibility and exponent of repulsive forces of eight poly(amide ester)s are calculated from the measured ultrasonic velocity and density values at different temperatures in N,N-dimethylacetamide solution. The abrupt change in ultrasonic velocity of polymer solutions at characteristic temperature is primarily due to the molecular interaction between polymeric molecules and to some extent, due to polymer-solvent interaction. Segmental motion starts at this temperature in the polymer solutions and are comparable to the glass transition temperatures determined for the solid samples by differential calorimetric method.

Keywords: Segmental motion, Poly(amide ester)s, Acoustical parameters, Ultrasonic velocity

 

 

Indian Journal of Chemistry

Vol. 53A, June 2014, pp. 695-699

 

Preparation, characterization and study of transport of organic hydrocarbon vapours through EVA-organo modified Cloisite®15A nanocomposites

N S Suja, C Jisha, S Vishnu Sankar & Anil Kumar S*

Postgraduate Department of Chemistry, NSS Hindu College, Changanacherry, Kerala, India

Email: anugraha_anil@yahoo.co.in

Received 8 November 2013; revised and accepted 5 May 2014

Nanocomposite membranes based on poly(ethylene-co-vinyl acetate) copolymer (18% vinyl acetate content) and organomodified clay Cloisite®15A have been prepared by mechanical mixing using two roll mill method with dicumyl peroxide as the cross linking agent. The morphology of the nanocomposites has been investigated using scanning electron microscopy and transmission electron microscopy. Samples with low filler content show excellent dispersion of layered silicates, resulting in a partially exfoliated structure. The diffusion and transport of vapours of organic solvents through the membranes have been investigated in detail as a function of clay content, nature of solvent and clay.

Keywords: Clays, Composites, Nanocomposites, Polymer-clay nanocomposites, Diffusion, Sorption, Transport

 

 

Indian Journal of Chemistry

Vol 53A, June 2014, pp. 700-705

 

 

Kinetics, thermodynamics and ion exchange characteristics
of thorium phosphate: An inorganic ion exchanger

Tarun Parangia, Bina Wanib & Uma Chudasamaa, *

aApplied Chemistry Department, Faculty of Technology & Engineering, The MS University of Baroda,
Vadodara 390 001, Gujarat, India

bChemistry Division, Bhabha Atomic Research Centre,
Mumbai 400 085, Maharashtra, India

Email: uvcres@gmail.com

Received 7 May 2013; re-revised and accepted 13 May 2014

Amorphous thorium phosphate, an inorganic cation exchanger of the class of tetravalent metal acid salts, has been synthesized by sol-gel method and subjected to physical, ion exchange and instrumental methods of characterization. Equilibrium constant values increase with increase in temperature for the transition metal ions (Co2+, Ni2+, Cu2+, Zn2+) and heavy metal ions (Cd2+, Hg2+, Pb2+) under study, indicating that the metal ions have higher affinity for the exchanger and that the mechanism is ion exchange. ∆G° values for all the exchange reactions are negative and become more negative with increasing temperature indicating increase in feasibility and spontaneity of the exchange process. ∆H° is positive in all cases indicating complete dehydration of ions for exchange to take place. R2 values are found to be close to unity for both Langmuir and Freundlich isotherms, providing a good fit to the experimental data for sorption of all the metal ions studied. Efficient metal ion separations have been performed which is supported by symmetrical bell shaped curves and the percentage of metal eluted. A study on regeneration and reuse of the ion exchanger shows that TP is effective up to four cycles without much decline in performance.

Keywords: Inorganic ion exchanger, Ion exchanger, Cation exchanger, Thorium phosphate,
Ion exchange thermodynamics