Vol. 11(2) June 2007
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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