Indian Journal of Chemical Technology

Research articles

Synthesis and evaluation of some organic vapour phase corrosion inhibitors	459
IPC Code: C23 F 13/00
M A Quraishi & D Jamal

Electrodeposition of Zinc-iron alloy	465
IPC Code: C25 D 3/56
Visalakshi Ravindran, R Sridevi, R Rajakumari, R Sekar & V S Muralidharan

Selective extractive spectrophotometric determination of cobalt using cyanex 923	470
IPC Code: G01 J 3/00, C01 G 51/00
Bina Gupta, Akash Deep, Virendra Singh & Shiv N Tandon

A rapid flame atomic absorption spectroscopic procedure for determination of lead in aluminium base alloys	475
IPC Code: G01 J 3/00, C22 C 45/00
A S Rao, K K Gupta, J K Sircar & S C Srivastava

Separation of cesium-137 from acidic fission product waste solutions using a complex inorganic exchanger (ZrP-AMP)	479
IPC Code: B01 J 39/02
V N Reddy, J Satyanarayana, S S Kumar, M V Sivaiah, R M Krishna, S Lakshminarayana & G S Murthy

Effect of some electric factors on the effective oxidation level of aluminum	486
IPC Code: G01 N 27/26
Peter D Dineff & Emilia K Sabeva

Preparation of a reusable strip of barley oxalate oxidase for determination of urinary oxalate	495
IPC Code: C03 C 17/22
S Madanpotra, R Chaudhary, S Singh & C S Pundir

Studies on PVC based chelating inorganic ion exchange resin membrane sensor for neodymium(III) ion	500
IPC Code: C08 J 5/22
A P Gupta, Himanshu Agrawal, S K Shukla & Vikas R Bharduwaj

High performance liquid chromatographic determination of astemizole in pharmaceutical dosage forms	504
IPC Code: B01 D 15/00, A61K
K Basavaiah, V S Charan & U Chandrashekar

Voltammetric studies of endosulphan	509
IPC Code: A01 N 31/00, G01 N 27/00
Sunita Kumbhat & Sushma Dave

Destabilization characteristics of talc in distilled and fresh waters	512
IPC Code: C08 J 3/00, C01 F 5/00
A Ozkan

Removal of arsenic from water by different adsorbents	518
IPC Code: C02 F 1/28
Rajeev Goel, S K Kapoor, Kshipra Misra & R K Sharma

Excess volumes of binary liquid mixture containing methyl butyrate with bromobenzene, chlorobenzene and nitrobenzene at 303K, 308K and 313K	526
IPC Code: G01 N 9/00
M V Rathnam & R K Singh

Comparison of SFE, ASE, and soxhlet extraction procedures for the determination of polycyclic aromatic hydrocarbons associated with airborne particulate matter	531
IPC Code: C07 C 15/00, B01 D 11/00
S M Talebi & A Taebi

Simulation of electro-mixer-settler for the partitioning of uranium and plutonium in PUREX process	535
IPC Code: B01 D 59/38, G06 F 17/00
N K Pandey & S B Koganti

Transport of Pu(IV) across supported liquid membrane from nitric acid medium using cyanex- 923 as the mobile receptor	548
IPC Code: C22 B 60/40
S R Sawant, J V Sonawane, Anil Kumar Pabby, A K Venugopalan, P K Dey &B Venkataramani

Sequestration and remediation of heavy metals by Brassica sp at Hindan river sites	555
IPC Code: (C02 F 3/32, 101:20)
Anwar Ahmad & Masood Alam

Design and fabrication of a catalytic reactor for treating automobile exhaust	560
IPC Code: B01 D 53/34
J Soji Adeyinka, J U Okoli & Yousuo Digineni

A facile synthesis of fatty acid esters of para-cresol catalysed by acid activated Indian Bentonite	565
IPC Code: C07 C 67/00, C07 C 39/07, B01 J 21/00
B Vijayakumar, Pushpa Iyengar, Gopalpur Nagendrappa& B S Jai Prakash

Oxidative coupling of methane over La-promoted MgO catalysts: Influence of precursors and method of catalyst preparation	569
IPC Code: B01 J 21/00
V R Choudhary, V H Rane & S T Chaudhari

Crystallization of HMX in acetone-water system	575
IPC Code: B01 D 9/02
Souraseni Basu, N M Gawande, M E Apte & V L Narasimhan

Educator

The nature of heat	582
Jaime Wisniak
Chem-Tech Scan	593
Author Index	597
Keywords Index	598

Synthesis and evaluation of some organic vapor phase corrosion inhibitors

Five organic volatile corrosion inhibitors (VCIs) were synthesized using 2-Dec-9-enyl-2-imidazoline with various acids such as maleic acid, orthophosphoric acid, nitrobenzoic acid, phthalic acid and cinnamic acid and evaluated as corrosion inhibitors of mild steel, brass and copper by weight loss method. Eschke test method, sodium chloride inoculation test method and sulfur dioxide (SO₂) test method were also carried out to investigate the corrosion inhibiting effect of the compounds. All the investigated VCIs exhibited good inhibition efficiency (IE) for all the metals. Cinnamate salt showed best result among all the studied compounds for all the metals.

Keywords: Eschke test, volatile corrosion inhibitor, imidazoline derivative, cinnamate salt, mild steel, brass, copper

Electrodeposition of Zinc-iron alloy

To protect steel against environmental attack, zinc-iron alloy deposition is used. Search for a noncyanide plating bath resulted in the development of sulphate bath. Current efficiency, throwing power and Hull cell studies were used to optimise a plating bath. The optimized plating bath composition is zinc sulphate 0.05M, ferrous ammonium sulphate 0.01M, sodium sulphate 20 g L^-1, boric acid 30 g L^-1, methanol 0.12M, triethanolamine 0.2M, ascorbic acid 2.5 mM and sodium lauryl sulphate 0.06M. Matte white deposits were obtained in the current density range of 2-3 Adm^-2.

Keywords: Electrodeposition, zinc-iron alloy, sulphate bath, alloy plating, triethanolamine, non-cyanide

Selective extractive spectrophotometric determination of cobalt using cyanex 923

The present paper describes a selective extractive spectrophotometric method for the determination of Co(II) using toluene solution of cyanex 923. A blue coloured complex (l_max685 nm) is quantitatively extracted in the organic phase from 7 – 10 mol L^-1 HCl. The composition of this complex is proposed as H₂CoCl₄.2cyanex 923. The Beer’s law is obeyed in the concentration range 0.0 – 4.2 ´ 10^-3 mol L^-1 Co(II) and the molar absorptivity of the complex is 5.6 ´ 10² L mol^-1cm^-1.The presence of hundred fold excess of metal ions such as Mo(VI), W(VI), V(V), Ti(IV), V(IV), Al(III), Cr(III), Fe(III), Mn(II), Fe(II), Ni(II), Cu(II), Zn(II) and Cd(II) and fifty fold of anions namely PO₄^3-,CO₃^2-,SO₄^2-,C₂O₄^2-, citrate, tartrate, NO₃^-and SCN^- do not interfere in the determination of Co(II). The accuracy of proposed procedure is checked by assaying the concentration of cobalt in two standard NBS steel samples. The applicability of the method is demonstrated by selective determination of Co(II) in a multi element system like polymetallic manganese sea nodules. The result is in fairly good agreement with those obtained by AAS and ICP-AES.

A rapid flame atomic absorption spectroscopic procedure for determination of lead in aluminium base alloys

A rapid and sensitive technique to determine lead in trace level present in aluminium based alloys by flame atomic absorption spectroscopic technique (AAS) is described. It is free from aluminium and silicon spectral interferences. The method is free from associated alloying elements. Lead was determined at 283.3 nm using air-acetylene flame. The value of relative standard deviation (r.s.d.) of lead, in case of high silicon containing samples is found to be 2.545% and that for low ones 10-12% respectively. The standard deviation values were +/- 0.0014 and +/-0.0016 respectively. A threshold limit of concentration of aluminium and silicon for the determination of lead in final analyte solution has been described and this has been correlated with the sample weight to be taken for analysis.

Keywords: Lead determination, aluminium ally, atomic adsorption spectroscopy

Separation of cesium-137 from acidic fission product waste solutions using a complex

inorganic exchanger (ZrP-AMP)

V N Reddy, J Satyanarayana, S S Kumar, M V Sivaiah, R M Krishna, S Lakshminarayana & G S Murthy

A new inorganic ion exchanger, zirconium phosphate-ammonium molybdophosphate (ZrP-AMP) has been prepared in granular form, suitable for column operation. The results obtained from TG-DTA, IR and X-ray diffraction studies for this exchanger are presented. The k_d values for different metal ions were determined and the affinity order was found to be Cs>>Rb>Zr>Ce>rare earths. pH titration curve, breakthrough capacities for cesium in different types of simulated nuclear wastes and elution of cesium from ZrP-AMP column have been studied. Conditions for separation and isolation of cesium from other fission products in simulated waste solutions have been established. The exchanger was found to be stable to a g-radiation dose of 10⁸ rads.

Effect of some electric factors on the effective oxidation level of aluminum

In the present work, conditions were set for a study of the effect of field geometrical structure, by its transition from uniform to non-uniform field by varying the ratio of anode and cathode active areas on the effective oxidation level, assumed to be a measure for non-conformity with Faraday law by the anodic dissolution of aluminum in solutions of sodium chloride. Non-conformity with Faraday law was observed as in the range of low current densities (lower than 80-150 Am-2) the effective oxidation level changes in a wide interval depending on the factors studied and electric field geometry; in the range of high current densities (higher than 80-150 Am-2) the effective oxidation level is slightly affected by the electric field geometry and conditions used.

Keywords: Electric field geometry, oxidation of aluminum, anodic dissolution

Preparation of a reusable strip of barley oxalate oxidase for determination of urinary oxalate

A reusable plastic strip of oxalate oxidase was prepared by immobilizing covalently, a partially purified barley oxalate oxidase on alkylamine glass beads affixed on a plastic strip with a non-reactive fixative. The immobilized enzyme gave a conjugation yield of 9.5 mg g^-1 support with 84.8% retention of initial activity of free enzyme. A method for discrete analysis of oxalate in urine was developed employing this enzyme strip. The method is based on measurement of H₂O₂ generated from urinary oxalate by strip bound oxalate oxidase by Trinder’s colour reaction. The minimum detection limit of the method was 0.9 µg 0.1mL^-1 urine. The recovery of added oxalate was 84.7%.Within and between assay co-efficient of variation were <7.3% and <15.6% respectively. A fair correlation (r=0.752) was found between oxalate values obtained by a commercial kit method. The method provides enormous ease in handling of immobilized enzyme during its reuse and is unaffected by Cl¯ found in biological fluids.

Keywords: Oxalate, oxalate oxidase, enzyme strip, urine, Sorghum, alkylamine glass, immobilized enzyme

Studies on PVC based chelating inorganic ion exchange resin membrane sensor for neodymium(III) ion

Tetracycline sorbed zirconium(IV) tungstophosphate (TC-ZWP) has been used as a chelating agent for determination of rare earth metal ion i.e Nd(III). The poly(vinyl-chloride)-based membrane electrode exhibits a Nertian response for Nd(III) ions over a wide concentration range (1x 10 ^-1 to 5x 10 ^-5 M) with detection limit of 5x 10 ^-5 M. It has 25 s response time and can be used upto 45 days without any divergence in its potentials. The proposed membrane sensor reveals good selectivity for Nd(III) ions within the pH range of 3-7. Analytical application of electrode has been investigated for the quantitative determination of Nd(III) in sibaiya phosphate ores. It has been also successfully used as an indicator electrode in the potentiometric titration of Nd(III) against standard EDTA solution.

Keywords: PVC membrane electrode, zirconium tunustophosphate, membrane sensor, neodymium(III) determination

High performance liquid chromatographic determination of astemizole in pharmaceutical dosage forms

A rapid, highly sensitive high performance liquid chromatographic method has been developed for the determination of astemizole that is suitable for routine use in quality control. The chromatographic conditions comprised of a reversed-phase C₁₈ column (250 x 4.6 mm) with a mobile phase of acetonitrile - 0.1% orthophosphoric acid, pH adjusted to 3.9 (80:20 v/v). The flow rate was 1.5 mL min^-1 and uv detection was set at 215 nm. The calibration graph was linear from 5.13 - 405.0 mg mL^-1. The method was validated according to ICH guidelines including the assay of commercially available tablets. Recoveries ranged from 98.10 to 101.90 %. The utility and accuracy of the method were further established by parallel determination by a reference method and by recovery studies. The excipients present in the tablets did not interfere.

Voltammetric studies of endosulphan

The cyclic voltammogram of endosulphan recorded in various supporting electrolyte in aqueous methanolic medium at hanging mercury drop electrode, revealed a single cathodic peak at -1.25 V versus Ag/AgCl . The electrochemical behaviour of endosulphan after nitration at micro level has been studied at glassy carbon electrode. The nitro derivative also revealed a sharp cathodic signal at -0.9 V versus Ag/AgCl. The electrode reaction is found to be irreversible and diffusion controlled. Cathodic peak appeared to be analytically useful.

Destabilization characteristics of talc in distilled and fresh waters

The destabilization characteristics of talc were investigated in distilled and fresh water containing Ca²⁺, Mg²⁺, Na⁺ and K⁺ions. The stability of the talc suspension remained almost constant in distilled water at all pH values, while it sharply decreased with these cations (i.e. in fresh water) at pH values above 10.5. In addition, the effects of A-95 (anionic), C-521 (cationic) and N-100 (non-ionic) flocculants on the destabilization of the suspension were also investigated in distilled and fresh waters. In fresh water, anionic and non-ionic flocculants were very effective on the talc suspensions at pH 7.2 and at pH values greater than 10.5. The stability of talc suspension was decreased by flocculation and also coagulation effect at pH levels greater than 10.5. The cationic flocculant caused weak destabilization of the suspension with distilled water in acidic conditions. However, this polymer was ineffective on the talc suspensions in fresh water at almost all pH levels.

Keywords: Talc, destabilization, stability, cations, polymeric flocculants, magnesium silicate

Removal of arsenic from water by different adsorbents

Present study is carried out for the removal of As( III) from water using commonly available adsorbents such as sand, from Yamuna river ( Delhi ), as well as from Ganga river (Kolkata ), activated carbon, Hametite ore and sand - iron scrap mixture. All these adsorbents are used as received but sand and activated carbon which do not show much adsorption for As(III) are modified by treating with different metal ions in order to improve their adsorption efficiency. Results of the laboratory experiments under static conditions have confirmed that iron impregnated granular activated carbon (GAC), spherical activated carbon (SAC) as well as sand - iron scrap mixture have much promise as a medium for the removal of As(III) in drinking water. Various parameters like adsorbent dose, contact time, pH and arsenic concentration are optimized. A simple and economical domestic arsenic removal kit has been designed and successfully evaluated in the laboratory using sand-iron scrap mixture as media for the removal of arsenic from water.

Keywords: Arsenic removal, hametite ore, activated carbon, sand, adsorption, drinking water

Excess volumes of binary liquid mixture containing methyl butyrate with bromobenzene,

chlorobenzene and nitrobenzene at 303K, 308K and 313K

Excess volumes for the binary liquid mixtures of methyl butyrate with bromobenzene, chlorobenzene and nitrobenzene have been calculated from the density data at 303K, 308K and 313K as a function of composition. Values of excess volumes (V^E) for all the systems studied are found to be highly negative over the entire range of composition. The negative values of V^E were found to increase with increase in temperature.

Keywords: Binary liquid mixture, methyl butyrate, halogenated hydrocarbon, excess volume

Comparison of SFE, ASE, and soxhlet extraction procedures for the determination of polycyclic aromatic hydrocarbons associated with airborne particulate matter

The efficiencies of three different extraction procedures including supercritical fluid extraction, accelerated solvent extraction, and soxhlet for extraction of polycyclic aromatic hydrocarbons from airborne particulate matter were investigated. Although the results obtained from the three methods and especially ASE and SFE were very close to each other, SFE was found as the most effective methods for extraction of PAHs from airborne particulate matter. The effect of temperature on the efficiency of extraction of PAH_sby SFE was also investigated and showed that the extraction efficiency can be improved by performing the extraction at higher temperatures.

Keywords: Polycyclic aromatic hydrocarbon, SFE, ASE, airborne particulate matter

Simulation of electro-mixer-settler for the partitioning of uranium and plutonium in PUREX process

The mathematical basis for a computer code PUSEP (Plutonium Uranium Solvent Extraction Program) for the analysis of partitioning cycle of PUREX process involving in-situ electrochemical reduction of uranium and plutonium is described in the present investigation. The basis of development of model equations involves countercurrent multi-component extraction coupled with chemical and electrochemical reactions. The model is specific to mixer-settler contactors and is restricted to mass transfer equilibrium. The components considered in the model equations are U(VI), U(IV), Pu(IV), Pu(III), nitric acid and hydrazine. Computer code provides transient behaviour of mixer-settler contactor from the start-up conditions to the steady-state conditions. The code has been validated with the experimental data available in literature. The calculated results are consistent with the experimental results considering the major components mentioned above.

Transport of Pu(IV) across supported liquid membrane from nitric acid medium using

cyanex- 923 as the mobile receptor

S R Sawant, J V Sonawane, Anil Kumar Pabby*, A K Venugopalan, P K Dey &B Venkataramani

Based on the solvent extraction data, experiments were conducted with Flat-sheet Supported Liquid Membrane (FSSLM) to examine the transport behaviour of Pu(IV) to achieve its maximum recovery. This is necessary to optimize the conditions for further operation of Hollow Fiber Supported Liquid Membrane (HFSLM) and Compact Supported Liquid Membrane Flow Cell (CSLMFC). A laboratory scale hollow fiber module, having membrane surface area, 134 cm², was employed in a recycling mode using ‘Enka’ Accurel hollow fiber polypropylene membranes as the solid support, cyanex-923 as the mobile receptor and dodecane as the membrane solvent. Dilute plutonium nitrate solutions in 1M HNO₃ generally constituted the source phase. Among the strippants, several reagents were tried, the most efficient strippant found was dilute uranous solution in 1.0M HNO₃. The recovery of Pu from the Pu oxalate supernatant generated during Pu reconversion operations in the PUREX process was tried, where it was observed that ~ 94 % of Pu(IV) could be transported in a single run of duration of 10 h, while employing 0.1M cyanex-923/dodecane as a mobile receptor and uranous solution in 1.0 M HNO₃ as the strippant. Parameters such as source phase concentration, source and strippant phase recirculation flow rate, concentration of carrier in the membrane and strippant, and interferences of other permeants on plutonium permeation pertaining to FSSLM, HFSLM and CSLMFC were optimized.

This followed the utilization of more application oriented configuration i.e. Hollow fiber membrane configuration for the above purpose.

With HFSLM, the K_obs values increased from 3.06 x10^-5 to 6.27 x10^-5 s^-1 by increasing flow rate from 0.03 x10^-6 to 0.14x 10^-6 m³/s at 1 h and the percentage permeation increased from 75 to 90%. In the case of CFSLMC, the K_obs increased from 5.41 x10^-5 to 5.74 x10^-5 s^-1 while increasing flow rate from 0.27 x10^-6 to 0.42 x10^-6 m³/s , at 1h and the percentage permeation increased from 65 to 85% .

Keywords: Pv(IV) transport, FSSLM, mobile receptor, cynex 923, dodecene, HFSLM, CSLMFC

Sequestration and remediation of heavy metals by Brassica sp at Hindan river sites

Various kinds of industries have grown up in and around city Ghaziabad (Sahibabad industrial area). The river Hindan is the principal sink of industrial effluents and agricultural wastewater. Industries discharge effluents directly into the river Hindan. The pollution is widespread but varies in its intensity and toxicity from place to place. The analyses and monitoring of some plants grown with water contaminated with industry effluent revealed the accumulation pattern of various heavy metals like Hg²⁺, Cd²⁺, Pb²⁺, Ni²⁺ and Zn²⁺ in different plants. Among the plants tested only Brassica juncea has potential to withstand contaminated river samples as it has means to sequester toxic metals in specific compartments.

Keywords: Brassica juncea, sequestration, remediation, heavy metals

Design and fabrication of a catalytic reactor for treating automobile exhaust

A reactor was designed for the conversion of exhaust pollutants from an internal combustion engine using gasoline as fuel. A bed height of 420 mm was used with an internal diameter of 40 mm; a space-time of 23.6s and a fractional conversion of 0.99 at a space velocity of 0.042 m/s was achieved. A catalyst formulation of PtO₂ (1%), Devarda alloy (Al, 45; Cu, 50 and Zn 5%) with NH₄VO₃ and g-Al₂O₅ support was prepared to meet the reaction specification of particle length 0.28 + 2mm, and diameter of 0.15mm. Performance evaluation of the pollutant conversion at 375°C + 25°C showed 98% conversion of CO, 99% of HC and NO_x 98% with 100% hydrogen utilisation.

Keywords: Devarda, exhaust converter, pollutants, void volume, catalytic reactor, IC engine, automobile exhaust

A facile synthesis of fatty acid esters of para-cresol catalysed by acid activated Indian bentonite

p-Tolyl esters of some long chain fatty acids having commercial applications are synthesized using acid activated Indian bentonite as catalyst. Experimental conditions have been optimised to get the best yields. The effects of the molar ratio and reaction time have been investigated. The rate constant (k), the equilibrium constant (K) and the standard Gibbs free energy (DG^o) are calculated. The spent catalyst on regeneration [by washing and heating to 110ºC] shows the same activity, and is found to be reusable several times.

Keywords: Acid activated Indian betonite, easterification, p-tolyl esters, regeneration, catalysis

Oxidative coupling of methane over La-promoted MgO catalysts: Influence of precursors and method of

catalyst preparation

The influence of precursors for La₂O₃ (viz. lanthanum acetate and lanthanum nitrate) and MgO (viz. magnesium acetate, magnesium carbonate and magnesium hydroxide) and catalyst preparation methods (viz. physical mixing of the catalyst precursors and coprecipitation using different precipitating agents such as ammonium hydroxide, ammonium carbonate and sodium carbonate) of La-promoted MgO (La/Mg = 0.1) catalyst on its surface area, total and strong basicity (measured in terms of CO₂ chemisorbed at 50 and 500^oC, respectively) and catalytic performance in oxidative coupling of methane (OCM) to C₂-hydrocarbons at different temperatures (750-850^oC), CH₄/O₂ ratios (4.0 and 8.0) for a high space velocity (51,360 cm³.g^-1.h^-1) has been investigated. The catalyst prepared using the coprecipitation method have higher surface area and basicity (total and strong basic sites measured in terms of CO₂ chemisorbed at 50 and 500^oC, respectively) but lower activity/selectivity, whereas, the catalyst prepared using the physical mixing method have lower surface area and basicity (both total and strong basic sites) but show higher activity and selectivity in the OCM process, depending upon the La- and Mg- salts used as the catalyst precursors. The catalyst, prepared by physical mixing using lanthanum nitrate and magnesium carbonate (prepared by precipitation from magnesium nitrate and sodium carbonate) as the catalyst precursors showed best catalytic performance in the OCM at different process conditions.

Keywords: Oxidative coupling, methane,La-promoted MgO catalysts, catalytic selectivity

Crystallization of HMX in acetone-water system

Cyclotetramethylene-tetranitramine (HMX) is prepared by continuous nitrolysis of hexamine using nitric acid and ammonium nitrate in the presence of acetic anhydride and acetic acid. HMX obtained after nitrolysis contains RDX and some nitro compounds as impurities. It is purified by evaporative crystallisation technique using acetone as the solvent. In this work a ternary system consisting of HMX as the solute, acetone as solvent and water as anti-solvent was studied in order to obtain solubility data and influence of different parameters viz. percentage recovery of solvent, stirrer speed, cooling rate, and rate of recovery of solvent on the crystal size distribution (CSD) of HMX. The crystal morphology was also studied by using scanning electron microscope (SEM). The CSD of HMX obtained by using acetone-water mixture is compared with the CSD obtained by using acetone as solvent. It has been observed that under similar conditions of crystallisation, crystals obtained from acetone-water mixture are smaller than those obtained from acetone. Also, the crystals obtained from acetone-water system are more regular in shape and have smooth surfaces.

Keywords: HMX, crystallization, acetone-water system, crystal size distribution

The nature of heat

The nature and effects of heat have intrigued philosophers and scientists since ancient times. Different theories were developed to explain the phenomena, and of these, the wave theory and the caloric theory were the ones that remained in force until the second half of the nineteenth century when overwhelming evidence led to the conclusion that heat was not a material substance, that the molecules of a gas were not stationary but could move in space, and that radiation and light were basically the same phenomena.

ISSN:0971-457X		CODEN:ICHTEU 11(4) 453-600
VOLUME 11	NUMBER 4	JULY 2004