Tanushree Choudhury

Bio: Tanushree Choudhury is an academic researcher from VIT University. The author has contributed to research in topics: Hybrid material & Membrane. The author has an hindex of 3, co-authored 7 publications receiving 49 citations. Previous affiliations of Tanushree Choudhury include Indian Institute of Technology Dhanbad.

Treatment of Methylene Blue and Methyl Orange Dyes in Wastewater by Grafted Titania Pillared Clay Membranes.

Abstract: Background Amphoteric membranes such as Titania Pillared Clay (TiPILC) membranes exhibit different charges at different pH ranges, subsequently show efficient separation for cationic and anionic organic pollutants in wastewater based on solution pH. The structural properties of such membranes determine their permeability and selectivity to a large extent. The present work is initiated to explore the possibility of enhancing the surface area of TiPILC membranes by grafting with 3- aminopropyltriethoxysilane. Method Grafted TiPILC membranes were fabricated by colloidal sol- gel route followed by dip coating, drying and sintering the membranes at 300°C. X-ray diffraction (XRD) spectra of the pillared photocatalyst membranes show the presence of only anatase phase, which exhibits better photocatalytic activity. Fourier Transform Infrared (FT-IR) spectra reveal the formation of delaminated TiPILC material. The specific surface area of TiPILC membrane obtained at pH3.5 is 183m2/g. Results Literature survey of 47 papers was carried out for the work. 10 papers were based on patents being dealt on degradation of organic dyes in wastewater by conventional methods, though reports of membrane technology are limited in literature. The rest 37 papers outlined the importance of widespread use of titania photocatalyst powder for degradation studies. Conclusion The membrane material thus developed is efficient in complete decolouration of both Methylene Blue and Methyl Orange dyes on account of the high surface charge and high surface area in just one cycle of filtration.

Thermal stability of PMMA-clay hybrids

Abstract: Materials with small particle size are being extensively used in composites and hybrid materials. Exfoliated clay-polymer hybrids show enhanced properties. Exfoliation of clay platelets can be affected by selecting dispersing agents. In the present work, clay dispersed by natural dispersant (soap stone powder), cetyl trimethyl ammonium bromide (CTAB) dispersed clay and acid clay (amorphous clay) are taken. They are then polymerized with poly methyl methacrylate (PMMA) by solution intercalation method. The thermal stability of these different clay-PMMA hybrids have been studied and compared with that of pure PMMA by differential scanning calorimeter (DSC). The bonding of clay with PMMA has been studied by IR. Morphology of clay-PMMA hybrids has been shown by SEM and XRD which indicate partially exfoliated structure in T606-4 and intercalated structures in T606-6 and T606-2.

Role of clay as catalyst in Friedel–Craft alkylation

Abstract: Solid acids have become increasingly important for many liquid-phase industrial reactions these days. Montmorillonite clays (2:1 clay mineral) have been used as efficient solid acid catalysts for a number of organic and liquid phase reactions and offer several advantages over classic acids. Tailor made catalysts can be prepared from clays by suitably adjusting their acidity and surface area by acid activation. In the present work, preparation, characterization and performance of Pt (II) clays, Cu (II) clays, acid clay, and sol–gel hybrids of Cu (II) clays as solid catalysts in a test Friedel–Craft alkylation reaction of benzyl chloride with toluene using differential scanning calorimeter (DSC) are reported. Product formation has been analysed by FTIR spectroscopy. The main objective of this work is to show how clay as a solid catalyst affects reaction rates and activation energies. Acidity and dispersion of solid catalysts are two main factors which govern a catalysis reaction. Kinetic parameter analysis and XRD studies confirm that acid Pt (II) clay and Pt (II) clay dispersed by natural dispersants are more effective catalysts. In contrast to the reactions using AlCl3, the experimental conditions are non-polluting and the final work up does not require any aqueous treatment.

Hybrid materials containg nanosized clay and natural fibre

Abstract: Clay particles that have the sizes a few nanometre thick, if properly dispersed in the polymer matrix impart unique combinations of physical and chemical properties that make these composites suitable for making coatings and films for a variety of industrial applications. Physical properties of nanocomposites can depend on the size of the incorporated colloids [1]. Clay minerals have also been used in making nanocomposites. A delaminated clay-polymer composite exhibit improvements in strength, modulus, thermal resistance etc [2]. Delamination (or, exfoliation) of clay depends on the dispersion of clay, and property of the composites depend on the interaction of delaminated clay with the polymer or, fibre. Natural fibre reinforced composites are employed as substitutes for synthetic fibre reinforced composites [3]. In the study hybrid material was prepared using montmorillonite clay and agave fibre. A natural dispersant was used for preparing exfoliated clay. Characterization of the materials were done using DSC, FTIR and SEM (Fig 1) Results show a show better dispersion of clay (by using a natural dispersant) and greater compatibility with natural fibres with finely dispersed clay particle. Such materials have great potential as a ecofriendly composite.

The Efficiency of Pt-Doped Titania Pillared Clay Membranes for the Treatment of Real Textile Wastewater: A Case Study

Abstract: Titania pillared clay membranes exhibit unique charge characteristics which are dependent on the solution pH. Doping of such membranes with precious metal like Pt induces a positive charge on the surface of the membranes, thus increasing its resistance against fouling. X-ray Diffraction (XRD) and Fourier Transform Infra-Red Spectroscopy (FT-IR) confirm the complete intercalation of anatase titania in the interlayer spaces of Montmorillonite in the present work. These membranes efficiently removed 83% of the dye from the real textile effluent in a one filtration cycle.

A critical review on the manufacturing processes in relation to the properties of nanoclay/polymer composites

Abstract: Nanoclay/polymer composites can be prepared by various processing techniques such as solution process, in-situ polymerization and melt blending. Each technique has an influence on the final charact...

Structural, thermal and electrical properties of poly(methyl methacrylate)/CaCu3Ti4O12 composite sheets fabricated via melt mixing

Abstract: Poly(methyl methacrylate) (PMMA) and CaCu3Ti4O12 (CCTO) composites were fabricated via melt mixing followed by hot pressing technique. These were characterized using X-ray diffraction, thermo gravimetric, thermo mechanical, differential scanning calorimetry, fourier transform infrared (FTIR) and Impedance analyser for their structural, thermal and dielectric properties. Composites were found to have better thermal stability than that of pure PMMA. However, there was no significant difference in the glass transition (Tg) temperature between the polymer and the composite. The appearance of additional vibrational frequencies in the range 400–600 cm−1 in FTIR spectra indicated a possible interaction between PMMA and CCTO. The composite, with 38 vol% of CCTO (in PMMA), exhibited remarkably low dielectric loss at high frequencies and the low-frequency relaxation is attributed to the interfacial polarization/MWS effect. The origin of AC conductivity particularly in the high-frequency region was attributed to the electronic polarization.

Nanocomposite of 2‐Aminophenol with Aniline Using Copper‐Montmorillonite: Synthesis, Characterization, Conductivity, and Electrochemical Study

Abstract: Polymer/clay nanocomposite particles with 2-aminophenol (2AP) and polyaniline and modified montmorillonite by copper minerals were synthesized using an in situ intercalative oxidative polymerization method. The nanocomposites were characterized by elementary analysis, X-ray diffraction, FTIR, thermogravimetric analysis, transmission electron microscopy, and conductivity measurements. The insertion of the polymer into the layer of the clay was confirmed by X-ray diffraction analysis, which shows a significantly larger d spacing expansion from 13.35 to 13.45 A, thus indicating that the conducting polymer chain was aligned with layers of the clay. The conductivity of the nanocomposites salt is between 8.87×10−5 and 9.78×10−4 S/cm, probably due to the confined environment in the nanometer size layers of the nanocomposite. The electrochemical behavior of the polymers extracted from the nanocomposites has been studied by cyclic voltammetry. Good electrochemical response has been observed for polymers grown into M-Cu; the redox processes indicate that the polymerization into M-Cu is electroactive.