Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

Oxidation of Nonylphenol in Water using O3

Kim Hyunook, Park Guisu, Yu Myongjin, Kim Eunjung, Ham Youngkook and Colosimo Mark F.

In this study, ozone (O3) was applied to oxidize nonylphenol (NP) and nonylphnol ethoxylates (NPEOs). Both oxidation performance and kinetics were evaluated under different operating conditions created by varying O3 doses,solution pHs or molar ratios of H2O2/O3.This study demonstrates that at pH 7, more than 90% NP (initial NP concentration: 0.51 mg/L) can be removed by 4 mg/L O3. In all pH range (5-9), NP was also effectively oxidized. However, the amount of NP destructed by O3 in the ID phase (instantaneous O3 demand during 30 sec) was more significant at higher pH. The NP destruction in the ID30sec phase was also significantly increased when H2O2 was applied along with O3. O3 was also found to be very effective in oxidizing NPEOs.

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Synthesis of Anhydrous, Monohydrate and Multihydrate 2, 4, 6-Trichlororesorcinol

Heasley Victor L., Renfrow Ronald E., Sator Lisa C., Boerneke Jeffrey L. and Shellhamer Dale F.

The data in this paper present a convenient synthesis of four forms of 2,4,6-trichlororesorcinol, 3: a multihydrate, a monohydrate, a kinetic anhydrous form and a thermodynamic anhydrous form. The multihydrate is prepared initially (using a significantly modified literature procedure) by the reaction of resorcinol, 1, in sulfuryl chloride, SO2Cl2, and acetic acid as a catalyst, and the other three forms are made from the multihydrate. Previous to this report, only the monohydrate form of 3 was clearly confirmed in the literature. The anhydrous form has been mentioned in the literature, but we were unable to repeat this study. The multihydrate form and the kinetic and thermodynamic anhydrous forms of 3 have not been mentioned previously. The four forms of 3 have been identified by an appropriate combination of the following approaches: gas chromatography, infrared spectroscopy, 1H and 13H nuclear resonance spectroscopy, mass spectrometry, and elemental analysis. Melting points are presented for each form; this will improve the literature markedly since a wide range of melting points is reported. Aside from intrinsic interests in the different forms of 3, the ease of preparation of 3 will make a contribution to synthetic chemistry. 2,4,6-Trichlororesorcinol, 3, is also of interest because it is an intermediate on the synthetic pathway of the pentachloro derivative, 2, of resorcinol, 1. Pentachloro derivative, 2, is an important model compound of the humic acids.

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Equilibrium and Kinetic Studies for the Adsorption of Mn(II) and Co(II) from Aqueous Media using Agar-agar as Sorbent

Gupta Bina, Begum Zareena I and Rajput Garima

The intensification of industrial activity and environmental accidents during recent years is greatly contributing to the increase of metal pollution in water resources, thereby causing threat to terrestrial as well as aquatic life. The toxicity of metal pollution is slow and long lasting, as these metal ions are non-biodegradable. The most appropriate solution for controlling the biogeochemistry of metal contaminants is sorption technique, to produce high-quality treated effluents from polluted wastewaters. Agar-agar, a readily available seaweed was used as sorbent for the removal of Mn(II) and Co(II) from aqueous media. Adsorption studies were performed by batch experiments as a function of process parameters: sorption time, pH, concentration of sorbate and sorbent. Freundlich model fitted best with the experimental equilibrium data among the two adsorption isotherm models tested. The kinetic data correlated well with the Lagergren pseudo second-order kinetic model for the sorption studies of both Mn(II) and Co(II) using agar-agar. Adsorbed metal ions were quantitatively recovered from the spent adsorbent using 5.0 mol L-1 HCl. The efficiency of agar-agar for decontaminating Mn(II) and Co(II) from the electroplating effluent has also been evaluated. The results proved agar-agar to be a favorable adsorbent to remove and recover Mn(II) and Co(II) from waste for further use in diversified industrial applications.

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Sorption Dynamics of Phenol on Naturally Occuring Low Cost Clay

Nayak Preeti Sagar and Singh B.K.

Most of the chemical contaminants are of organic origin. Phenols are among the most common water pollutant. Naturally occurring clay is new non-conventional sorbent having good sorption quality. Clay for the sorption of phenol from aqueous solution at different particle size, pH, concentration and temperature has been investigated by the batch shaking sorption experiment. It is found that the sorption of clay sample for phenol increases by decreasing particle size, pH and increasing temperature. The sorption process is described by means of the pseudo-second order mechanisms. The objective is to test the pseudo-second order model for analyzing the sorption of a phenol onto clay and to assess the usefulness and accuracy of the model. A rate parameter k has been defined and used to describe the sorption of phenol onto clay and experimental data were calculated. This helps to design a treatment plant for phenolic effluents where continuous removal can be achieved on a large scale.

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Synergistic Effect of Biocides Toxicity to Liza klunzingeri (Mugilidae: Perciformes) in Kuwait Marine Ecosystem, off the Arabian Gulf

Bu-Olayan A.H. and Thomas B.V.

Biocides (formaldehyde HCHO, sodium hypochlorite NaOCl and glutaraldehyde C5H8O2) that are commonly used in thermal, desalination and power plants and industries located near Kuwait Bay sites (I-III) were toxically tested on commercially important mullet fish, Liza klunzingeri. Multi-factor Probit analysis toxicity tests (96 h) on L. klunzingeri showed the lowest observed effective concentration LOEC at 0.019 mg/l (corresponding exposure at LC15 and maximum effect at median lethal concentration (LC50) with NaOCl followed by HCHO and C5H8O2. Marking’s equation on toxicity of mixture showed additive toxicity with biocides in combination of 1:1 ratio. Site-wise analysis showed more additive biocides toxicity in L. klunzingeri tested with seawater collected from site I when compared to sites II-III. Reasons may be attributed to the synergic influences of hydrological variables and the biocide discharges into the Bay. These results may characterize (1) the use of L. klunzingeri as a pollution indicator and (2) quantify the synergistic effect of biocides toxicity in mullet fish.

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Synthesis, Characterization and Dissolution of Biomorphic Ceramics – Determination of Metal Ions

Ojeda Bosch C. and Rojas Sánchez F.

Ceramic and glasses are some of the more recent and more resistant materials of engineering to the environmental conditions. They belong to advanced materials more than they are being developed for the aerospace and electronic industry. In the last decade, a new class of ceramic materials has attained particular attention. The materials were produced with natural, renewable resources (wood or wood-based products). In this work a new biomorphic ceramic material from oak wood and Si infiltration has been synthesized. After the material characterization, the dissolution of sample by acid attack in an oven under microwave irradiation was optimized. Experimental designs were used as a multivariate strategy for the evaluation of the effects of varying several variables at once. The optimization was performed in two steps using factorial design for preliminary evaluation and a Draper-Lin design for determination of the critical experimental conditions. Five variables (time, power, volume of HNO3, volume H2SO4 and volume of HF) were considered as factors and as response the concentration of different metal ions in the optimization process. Interactions between analytical factors and their optimal levels were investigated using a Draper-Lin design.

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The Kinetics Studies on the Rapid Iodination of Anthranilic Acid by Iodine Monochloride in Aqueous Solution

Zope V. S., Bonde S. L. and Dangat V. T.

The iodination of anthranilic acid by iodine Monochloride in aqueous solution has been studied by Rotating Platinum Electrode (RPE) technique. Unlike iodination by iodine in potassium iodide, which is slow and can be studied iodometrically, iodination by iodine monochloride is rapid and requires the use of a special technique. Iodine monochloride is electro reducible at RPE giving diffusion current which is linearly proportional to its concentration. As iodine monochloride is the only species in the reaction system which is electro reducible at suitably applied potentials, the course of the reaction is followed by measuring the diffusion current generated by the iodine monochloride at the RPE at the interval of times. Iodination is pH dependent, hence it has been carried out in buffered solution of pH-4. Due to presence of H+ ions the hydrolysis of iodine monochloride is suppressed, the reaction equilibrium is given as ICl + H2O = HOI + H+ + Cl-. Addition of supporting electrolyte (KCl) serves to further suppress this hydrolysis. The specific reaction rate at 25.5 OC was found to be 3.95 x 102 M-1S-1 and energy of activation as 64.28 KJ mole-1. A suitable mechanism for the iodination has been proposed.

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Indirect Complexometric Determination of Mercury(II) using DL-Pencillamine as a Demasking Reagent

Joseph Bincy and Joseph Abraham

A rapid, sensitive and selective complexometric method of determination of mercury(II) in the presence of other ions based on the technique of masking and demasking using DL-pencillamine is described. Mercury(II) present in the aliquot is first complexed with a known excess of EDTA and the surplus EDTA is titrated back with lead nitrate solution at pH 5-6 using xylenol orange as indicator. A known excess of 1% solution of DL-pencillamine is then added. The mixture is shaken well and the EDTA released from Hg-EDTA complex is titrated against the standard lead nitrate solution. Accurate and reproducible results are obtained for 4.01-60.15 mg of mercury(II) with relative error ±0.25% and standard deviation is <0.06 mg. The interference of various ions is also studied. This method was applied to the determination of Mercury(II) in its complexes and alloy compositions.

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Study of Thermodynamic Functions Values for CTAB

Monajjemi M., Naderi F., Aghaie H., Yari M., Mansoor Dalili N., Afsharnezhad S. and Mollaamin F.

Because of the strong association of DNA to CTAB containing vesicles, CTAB is widely used in model systems. Cetyl Trimethyl ammonium bromide as a cationic surfactant and also CTA (Cetyl trimethyl ammonium) were studied. After optimiza-tion, the values of thermodynamic functions, chemical shifts and Mulliken charges were obtained by Freq and NMR calculations in Gaussian program. Good results were obtained corresponding the experimental data

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The Mechanism of Sorption of Mercuric Ion (Hg2+) by Sargassum cristaefolium

Alcantara Rochelle T. and Apodaca Dahlia C.

Previous studies have indicated that Sargassum cristaefolium is capable of binding with metal ions. The metal sorbing property of Sargassum cristaefolium suggests its possible participation in the removal of Hg2+ ions in water and wastewater. However, the potential application of Sargassum cristaefolium for environmental remediation and precious metals recovery depends on the understanding of the mechanism involved. This study has attempted to explain the sorption process involving the binding of Hg2+ ions to Sargassum cristaefolium by deducing the mechanism involved and by determining the effect of competing ions. The sorption of Hg2+ ion is affected by the efficiency of the release of counterions such as K+ and Na+. A significant amount of K+ ion and few amounts of Na+ and Ca2+ ions were found to be displaced upon the binding of Hg2+ ions. The total concentration of counterions displaced corresponds to the total amount of Hg2+ ion bound to the Sargassum which is typical of an ion exchange behavior. A complex model of BM0.5 or B2M can be expected from the binding of Hg2+ ion to the Sargassum cristaefolium.

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Short Communication: Extractive Spectrophotometric Determination of Palladium(II) with 2-Hydroxy 3-Nitro 5-Methyl Acetophenone Oxime(HNMA)

Lokhande R.S., Sawant Abhay D. and Barhate V. D.

2-Hydroxy-3-Nitro-5-Methyl Acetophenone Oxime (HNMA) extracts Palladium (II) quantitatively (99.96%) into chloroform from an aqueous solution of pH 0.0 - 4.0 and from 0.1– 1M solution of acetic acid and mineral acids. The chloroform extract shows an intense peak at 430 nm (ë max). Beer’s law is obeyed over the Pd (II) concentration range 0.1-10 µg cm-3. The molar absorptivity is 15796 dm3 mole-1cm-1 at 430 nm. The composition of extracted species is found to be 1:2 (Pd : HNMA) by Job’s continuous variation and mole ratio method. The interference by various ions has been studied. The proposed method has been applied for determination of Pd (II) in catalyst sample.

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Mini Review-Green Cluster: Organic Reactions in Superheated Water

Fernando de Carvalho da Silva

At high temperatures and pressures, pure liquid water becomes a surprisingly effective medium for the reactions of organic compounds.

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Mini Review-Green Cluster Metal Dodecyl Sulfates: Combined Lewis Acid-Surfactant Catalyst (LASC)

Shiri Morteza

Metal dodecyl sulfates known as “combined Lewis acid-surfactant catalyst (LASC)” act in dual role both as a catalyst to activate the substrate molecules and as a surfactant to increase the concentration of organic reactants to form micelle particles in water.

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Metallic Triflimidates: Green Lewis Acids Catalysts

Grau Fanny

Typical Lewis acid catalysts can be advantageously replaced by metallic triflimidates which exhibit superior activity and efficiency.

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Review Paper: Biodegradable Polyurethanes in Medical Applications

Feng Yakai, Zhang Li and Wu Zhenzhen

Biodegradable polyurethane materials, which possess excellent properties such as biocompatibility and mechanical strength, facile formation etc. have been widely used in medical applications. The new applications and research progresses in this area are introduced in this paper. Histocompatibility, blood compatibility and degradation of polyurethanes are also discussed. In addition, the multifunctional biodegradable polyurethanes are also reviewed.

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Halogen-free Polymeric Flame-retardants for Commom Resins

Liu Y. Y. , Wang S. J., Xiao M. and Meng Y. Z.

Recent developments of halogen-free flame-retardants of general resins, which are epoxy resins, polyphosphates resins, polycarbonates resins and phenol formaldehyde resins are reviewed. We focused on the reactive additives or inherent flame retardant resins. Some reactive additives can be used in several kinds of resins. Among these resins, phenyl formaldehyde (PF) resins are the most flame resistant resins and pure PF resins have Limiting Oxygen Index (LOI) value of 35. The phosphorous-containing compound is the most flame resistant additive, not only as reactive additive but also as physical additive. The flammability testing methods and mechanism of some flame retardant elements or their flame-retardants are also introduced.

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