Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

Preparation of Composite Nanoparticles on the Base of Starch

Mojumdar Subhash C., Capek Ignác, Capek Peter, Fialová Lenka and Berek Dušan

The miniemulsion polymerizations of hydrophobic monomers styrene (St), butyl acrylate (BA) and methyl methacrylate (MMA) in the presence of carboxymethylated starch (CMS) were investigated. The emulsions were stabilized by nonionic emulsifier Tween 20 (Tw 20). The synergistic effect of starch on the particle nucleation and stability is observed at high emulsifier concentration. The strong particle agglomeration and degradation of polymer emulsion was observed in the miniemulsion polymerization of MMA with starch. The robust continuous phase polymerization of MMA is connected with agglomeration of polymer and consequently by the strong agglomeration of polymer particles. The limited water-phase polymerization of styrene (grafting) does not form enough long hydrophobic chains of (grafted) radicals due to which the entry of such radicals is limited as well as the participation of grafted polymer on the particle stabilization. Starch acts as a relatively good (co)stabilizer for the miniemulsion polymerization of BA, a poor stabilizer for the miniemulsion polymerization of St and a coagulative agent for the miniemulsion polymerization of MMA, respectively.

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Preparation and Photocatalytic activities of Fe3+ Doped Nanometer TiO2 Composites

Xiaohong Hu, Taicheng An , Maolin Zhang, Guoying Sheng and Jiamo Fu

Nanometer Fe3+ doped TiO2 and TiO2/Fe2O3 coupled oxides photocatalysts were prepared with different content ferric citrate and different opposite anions of iron using the Ti(SO4)2 precipitation method. The precursors of nanometer TiO2 were analyzed by thermogravimetric and differential thermal analyses (TG/DTA) and both nanometer photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and UV–VIS diffuse reflectance spectrum (DRS). The results showed that the mean size of nanometer TiO2 in both photocatalysts decreased with the increase in Fe3+ doped content. The photocatalytic activities of prepared catalysts were evaluated under UV light irradiation using methyl orange as a mode organic pollutant in water. The results showed that a small amount of iron dopants in TiO2 crystalline matrix could enhance the photocatalytic efficiency. The prepared TiO2 samples exhibited even higher photocatalytic activities than that of Degussa P25, the optimal amount of doped Fe3+ was 0.05%. However, with increase of iron element amount, at 25% and 50% contents, the nanometer particle becomes the coupled oxides of TiO2/Fe2O3. Moreover, the effect of different doped anions coming from different ferrous salts on the photocatalytic activities of Fe3+/TiO2 was also investigated, and the best doped opposite anion is found as SO42-.

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Indirect Spectrophotometric Determinaton of Vanadium ( IV )

Desai Sandip A. and Dhomane Abha S.

Spectrophotometric method for trace determination of Vanadium (IV) has been developed based on reduction of absorbance of alkaline potassium permangnate solution. Vanadium (IV) gets oxidized by alkaline potassium permangnate solution to Vanadium (V) in presence of barium ion. Hence reaction of Vanadium (IV) results in reduction in optical density of alkaline potassium permangnate solution containing barium ion. This reaction is exploited to develop a simple, rapid and sensitive method for trace determination of Vanadium (IV). The reaction was studied under different conditions and different parameters were checked. The calibration curve, which is a plot of decreasing absorbance value of potassium permangnate solution at 540 nm against increasing concentration of Vanadium (IV) is linear up to six ppm.

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Comparative Study and Treatment of Synthetic Dye Water using Poly Vinyl Alcohol Coated Activated Wood Charcoal as Adsorbent

Daga Kailash, Gehlot Poonam and Mehta Rishika

The comparative studies to explore the potential of Poly vinyl alcohol coated carbon black as low cost and biodegradable adsorbent to treat dyes have been conducted. The operating variables studied are pH, initial dye concentration/adsorbent concentration ratio and contact time. Batch kinetic and isotherm experiment were conducted to determine the sorption –desorption behaviour of the examined dyes from aqueous solution .The aim of the present work is to study the effectiveness of the adsorbent to remove dyes from their aqueous solution and the removal of colour from textile wastewater.

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Use of Anion Clay Hydrotalcite to remove Coloured Organics from Aqueous Solutions

Zakaria Nor Hanisah, Yasin Yamin and Ahmad Faujan B. H.

Anion clay hydrotalcite adsorbent was prepared to investigate their adsorption capabilities in the removal of humic acid from aqueous systems. Anion clay hydrotalcite was found to be particularly effective at removing negatively charged species. Its excellent uptake levels of anionic species can be accounted for by its high surface area and anion exchange ability. The potential feasibility of anionic clay hydrotalcite for removal of coloured organics from aqueous solution was investigated. The effects of various experimental parameters such as contact time, temperature and adsorbent dosage were investigated. The extent of humic acid removal increased with the increase in contact time, temperature and amount of adsorbent used. Adsorption data was better fitted to the Langmuir isotherm. The results in this study indicated that anioic clay hydrotalcite was an attractive candidate for removing humic acid which shows great colour reduction of humic acid solution.

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Volume and Transport Properties of Binary Liquid Mixtures of Propyl Acetate with Butan-1-ol, Pentan-1-ol and Hexan-1-ol at 308.15 and 313.15 K.

Desale Bhatu S.

The densities and viscosities of binary mixtures of propyl acetate with butan-1-ol, pentan-1-ol and hexan-1-ol have been measured over the entire range of composition at 308.15 and 313.15 K and at atmospheric pressure. Excess Gibbs free energy of activation of viscous flow (GDE) and Grunberg-Nissan interaction parameter (d) of binary liquid mixtures is useful in understanding the nature of intermolecular interactions between two liquids.

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Biodegradation Study of Starch – Acrylic Graft Copolymers

Shaikh M.M. and Lonikar S.V.

In the present work, the enzymatic degradation of a series of graft copolymers of starch has been studied. The biodegradation of the graft copolymers was followed colorimetrically by monitoring the liberation of carbohydrate as a consequence of starch hydrolysis by α – amylase. The results show that the extent of biodegradation varies from 63 to 59% in 28 h for starch-g-poly(acrylic acid), from 63 to 42% in 28h for starch-g-poly(methacrylic acid) and 63 to 27% in 38h for starch-g-poly (methyl methacrylate) depending upon the percentage add-on of monomers. The relatively slow extent of degradation in case of starch-g-poly(methyl methacrylate) is attributed to the hydrophobic nature of poly (methyl methacrylate).

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Potentiometric Determination of Terbium (III) ion Using Zirconium (IV) Boratophosphate as an Electroactive Material

Mittal S. K., Kumar Raj, Dogra Pernita and Sharma Harish K.

Membranes containing varying compositions of electroactive material and epoxy resin as binder were prepared and it is seen that the one having composition 60% ZrBP and 40% epoxy resin exhibits best performance. It shows excellent response in the concentration range of 10-4 M to 10-1 M Tb (III) ion with super-Nernstian slope of 45 mV/decade. It has fast response time of 15 seconds. Effect of internal solution was studied and the electrode was successfully used in partially non-aqueous medium. The proposed sensor revealed good selectivity with respect to alkali, alkaline earth, some transition and rare earth metal ions and can be used in the pH range of 2.0-10.0. It was used as an indicator electrode in the Potentiometric titration of Tb (III) ion against EDTA

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Studies of the Mechanism of Poly (vinyl alcohol) (PVA) Adsorption on the Calcite/Water Interface in the Presence of Sodium Oleate (SOl)

Sofiane Labidi Nouar, Djebaili Baki A. and Abdelkader Iddou

An influence of poly (vinyl alcohol) PVA with sodium oleate (SOL) interaction on the adsorption behavior of the polymer at CaCO3/solution interface was investigated by measure-ments the adsorbed amount, FTIR spectra, X-Ray diffraction and zeta potential. Effects of solid to liquid ratio and temperature was also examined. Observed increase of the PVA adsorption in the presence of Sodium oleate resulted from a polymer-surfactant complex formation. The presence of the surfactant influences also on the structure of the adsorbed polymer layers. This effect was proved by adsorption measurements that allow to calculate thickness of the adsorbed layer of the polymer on the surface of CaCO3 in the presence and the absence of sodium oleate. The amount of PVA adsorbed decreases with increasing solid to liquid ratio and increasing temperature beyond 45°C.

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The Rate Determining Step in Adsorption Processes

Vasanth K. Kumar and Porkodi K.

A kinetic model was developed to determine the kinetics and mechanism of adsorption process on the basis of unit volume of sorber. An effectiveness factor for adsorption systems is defined for the first time considering the diffusion limitation of the proposed model. The kinetic model was proposed for a flat shaped adsorbent for a first order kinetics. A Thiele modulus was defined first time corresponding to the adsorption process to determine the rate controlling step in the sorption process. The proposed model was found to be valid for the geometrical adsorbent shape such as slab, cylinder and sphere. The present model was found to be excellent in determining the transport mechanism and the corresponding mass transfer coefficients overcoming the existing theoretical models.

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Response of Fathead Minnows (Pimephales Promelas) to Arsenic using the 96-hour Toxicity Test

Apodaca Dahlia C., Laurio Maricon M. and David Carlos Primo C.

The objective of this study was to establish the lethal concentration of arsenic in fathead minnows using the 96-hour toxicity test. In view thereof, specific objectives of the present study were: to expose the fathead minnows to different arsenic and iron concentrations, to determine the highest arsenic concentration that the minnows can survive and to determine the effect of iron relative to the response of fathead minnows to arsenic when both are present in water.

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Photo Oxidation of Textile Industrial Effluent in the Presence of Semiconductor Particles by Solar Exposure

Naik S. Prakash, Puttaiah E.T., Kiran B.R., Babu K. Harish and Mahadevan K.M.

The efficacy of the photocatalyst using TiO2, ZnO and H2O2 for decolorizing textile industrial effluent using solar light illumination was investigated. The result shows that combination of TiO2 and H2O2 treatment provided maximum color removal, when compared to TiO2 alone. The data showed that the colour and COD removal by photocatalytic treatment for dosage of both TiO2 and ZnO at 1.5 mg / 50 mL of effluent with small amount (0.5mL) of H2O2 is the optimum dosage for photocatalysis. Increased or decreased concentra-tion of these optimum dosage retards the rate of photocatalysis. The present data revealed that at acidic pH (2-6) the color removal and COD reduction was maximum. When compared to TiO2 and ZnO, the performance of TiO2 is better than ZnO.

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Mini Review-Green Cluster: NaIO4/Silica: A safe and efficient reagent

Ferreira Sabrina Baptista

Sodium periodate supported on silica gel is an environment-friendly feasible reagent which can be applied in different organic reactions.

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Metalloporphyrins as Catalyst in Organic Synthesis

Rezaeivalla Majid

Metalloporphyrins are important catalysts which can increase rate and selectivity of many organic reactions.

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p-dodecylbenzenesulfonic Acid: A Brønsted Acid-surfactant-combined Catalyst

Shrikhande Janhavi J.

Dodecylbenzenesulfonic acid (DBSA), an anionic surfactant, can act as a combined Brønsted acid-surfactant-catalyst (BASC). It performs the dual role of both, an acid catalyst to activate the substrate molecules and a surfactant to increase the concentration of organic reactants by forming micellar aggregates in water.

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Review Papers: Distribution and Removal of Radionuclides from Contaminated Medium: A Review

Virkutyte Jurate and Sillanpää Mika

The threat of radionuclide pollution to the environment has contributed to an increased interest in developing the most efficient soil and water treatment systems. To efficiently mitigate adverse radionuclides impacts and specify the most feasible treatment technology, it is vital to determine radionuclides geochemical behavior in the soil and water. The objective of this study is to summarize recent research attempts on the distribution and potential removal of radionuclides from contaminated medium. Primary attention was focused on the speciation and migration of radionuclides as well as on the physicochemical and biological treatment technologies. From the treatment methods considered, it is apparent that there is no single available solution for the efficient removal of radionuclides from soil and water, which is both economically and technologically feasible. The main problems are associated with the long removal time and high technological costs. Therefore, to overcome these disadvantages, it is necessary to combine several conventional and/or innovative technologies.

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