Arsenic Removal from Potable Water
Using Copolymer Resin-III Derived from p-Cresol
-- Sanjiokumar S Rahangdale and Wasudeo B Gurnule
Copolymer was synthesized by condensation of p-Cresol (p-C) and Adipamide (A) with Formaldehyde (F) in the presence of 2M HCl as catalyst with 4:1:5 molar ratios of reacting monomers. Water is the most important constituent of our body. Thus, its quality should be good and perfect because it directly affects our health. Water pollution due to arsenic leaching is one of the biggest problems all over the world. Ion-exchange studies of this purified copolymer resin were carried out for As3+ ions. ‘A’ proved to be a selective chelating ion-exchange copolymer for certain metals. Chelating ionexchange properties of this copolymer were studied for As3+ ions. Batch equilibrium method was employed to study the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The copolymer showed a higher selectivity for As3+ ions.
© 2011 IUP. All Rights Reserved.
Excess Thermodynamic Properties of Binary Mixtures
of Acetophenone with Methanol, Hexane,
Dimethylformamide and Tetrahydrofuran at T = 308.15 K
-- Shipra Baluja, Jagdish Movalia and Nilesh Godvani
Density, viscosities and speed of sound of binary mixtures of acetophenone with methanol, hexane, Dimethylformamide (DMF) and Tetrahydrofuran (THF) were measured at 308.15 K. Excess molar volume, excess viscosity, excess isentropic compressibility and viscous flow of activation of mixtures were estimated from the experimental results.
© 2011 IUP. All Rights Reserved.
Flow-Injection Chemiluminescence Determination
of Thiosemicarbazyl Compounds in Insecticides
-- Zoumana Sekou Traore and Xingguang Su
This paper reports a sensitive, simple and rapid flow injection chemiluminescence
method for the determination of thiosemicarbazyl compounds in insecticides. It was
found that the thiosemicarbazyl compounds have the tendency to inhibit the
Chemiluminescent (CL) signal generated by KMnO4 – Na2SO3 system in the acidic
medium. The linear correlation between the generated CL and the concentration
logarithm was detected in the range of 7.3 × 10–9 – 5.4 × 10–7 M for Thiosemicarbazide
(TSC) and 6.8 × 10-–9 – 3.6 × 10–7 M for the thiosemicarbazone; with the relative standard
deviation (for 12 measurements) of 2.3% and 2.6% respectively. The limits of detection
(3s) are 2.2 × 10–10 M and 1.8 × 10–10 M respectively. The sample throughput is 100
samples/h. The proposed method was used to determine the TSC in the synthetic
samples with satisfactory results. To prove the practical use of the method, it was
applied to determine the TSC and thiosemicarbazone concentrations in insecticides
purchased in the market.
© 2011 IUP. All Rights Reserved.
Effects of Substituent on Antioxidant Potent Substituted
Styryl 3, 4-Dichlorophenyl Ketones
-- G Thirunarayanan
A series containing 16 substituted styryl 3, 4-dichlorophenyl ketones [(2E)-1- (3, 4-dichlorophenyl)-3-phenyl-2-propen-1-ones] were synthesized by solvent-free stereo selective crossed-aldol reaction. The group frequencies of the Infrared (IR) and Nuclear Magnetic Resonance (NMR) spectra were assigned. The assigned spectral frequencies were correlated with Hammett substituent constants using single and multiparameter correlation equations. The influence of substituent effects on the group frequencies were predicted from the results of statistical analyses. The antioxidant activities of these ketones were studied using the 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) radical scavenging method.
© 2011 IUP. All Rights Reserved.
Complexometric Determination of Indium(III)
and Thallium(III) Individually and in Mixtures
Using Methylene Blue as Ion-Pair Indicator
-- Tesfahun Kebede, B B V Sailaja and M S Prasada Rao
Conditions have been established for the determination of Thallium(III) (Tl) and
Indium(III) (In) individually and in mixtures. In the presence of sufficient chloride
ions, Tl(III) forms the tetrachlorothallate(III), TlCl4
–, which forms a stable ion-pair
association with the cationic part of methylene blue. Tl(III) is determined alone by
direct titration with Ethylenediaminetetraacetic Acid (EDTA) using methylene blue
as an ion-pair indicator. In(III) is titrated with EDTA in the presence of a known
amount of Tl(III) and sufficient chloride with methylene blue as an ion-pair indicator.
Moreover, direct titration of a mixture containing the two metal ions with EDTA
results in successive complexation of the ions, first with In(III) and then with Tl(III).
The equivalence point is reached in all cases when the pink color of the ion-pair
association turns to blue. The titer value for the mixture corresponds to the total of
In(III) and Tl(III) and a blank correction corresponding to Tl(III) is applied. In the
analysis of the mixtures, the total amount of In(III) and Tl(III) is estimated
complexometrically, while the Tl(III) alone is estimated bromatometrically after
reducing to Tl(I). The amount of In(III) is calculated by difference.
© 2011 IUP. All Rights Reserved.
Enthalpy of Mixing and Vaporization of Esters with Alcohols
(Methyl Acetate – Methyl Alcohol and
Ethyl Acetate – 2-Butyl Alcohol) at 298 and 308 K
-- Nandini Mallikarjun, Shivaranjini R Desai and K L Shivabasappa
Thermodynamic properties of mixtures play a crucial role in the design of chemical separation equipments. The objective was to determine the enthalpy of mixing and vaporization of binary mixture (Ethyl acetate – 2-Butyl alcohol and Methyl acetate – Methyl alcohol) at ambient pressure. The experiments were carried out in two phases. Initially, enthalpy of mixing was measured at 298 and 308 K, and later, the heat of vaporization was conducted for the same mixtures. The enthalpy of mixing was measured by static calorimetric method using cylindrical Dewar flask at varied composition. The mixing enthalpies of Methyl acetate – Methyl alcohol are positive over entire composition with an average percentage deviation of –0.032 and –0.01 at 298 and 308 K. Ethyl acetate – 2-Butyl alcohol are also positive over the entire composition with an average percentage deviation of –0.025 and –0.003 at 298 and 308 K. Furthermore, the heat of vaporization was measured by evaporative method using a flow calorimeter. In this phase, the average percentage deviation of Methyl acetate – Methyl alcohol is –0.056 and Ethyl acetate – 2-Butyl alcohol is 1.06. The experimental results can be used to define the thermodynamic property of binary mixtures and to analyze intermolecular interaction. The data can be used in design calculation of chemical separation equipments.
© 2011 IUP. All Rights Reserved.
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