Indian Journal of Chemical Technology
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VOLUME 13

NUMBER 2

MARCH 2006

CODEN: ICHTEU

 

ISSN:0971-457X

 

 

CONTENTS

Papers

 

Kinetics of palladium catalysed partial oxidation of methane

107

IPC Code: B01J19/00

 

M A Lourdu Antony Raj, G M Madhu  & Y Jagannadha Rao

 

 

 

Use of semiconducting iron(III) oxide in photocatalytic bleaching of some dyes

114

IPC Code: C09B62/00, C09B57/00

 

Rajat Ameta, Jitendra Vardia, Pinki B Punjabi & Suresh C Ameta

 

 

 

Immobilization of α-amylase onto alkylamine glass beads affixed inside a plastic beaker: Kinetic properties and application

 

119

IPC Code: C11D1/00

 

S Dhingra, M Khanna & C S Pundir

 

 

 

Biosorption of iron(III) from aqueous solutions using the husk of Cicer arientinum

122

IPC Code: C02F1/28

 

N Ahalya, R D Kanamadi & T V Ramachandra

 

 

 

Corrosion inhibition of brass by thiocarbamides

128

IPC Code: C23F11/00

 

K K Taha, B S Sheshadri, M F Ahmed & V S Muralidharan

 

 

 

Acetic Acid leaching of magnesia from magnesite via calcination

135

  IPC Code: C04B2/00

 

  Ayhan Demirbas

 

 

 

Prediction of bed fluctuation ratio for gas-solid fluidization in cylindrical and non-cylindrical beds

 

139

IPC Code: B01J8/00

 

R K Singh & G K Roy

 

 

 

Holdup measurement in a gas-liquid ejector for a sodium chloride-air system

144

  IPC Code: F04B47/00

 

P T Raghuram & T R Das

 

 

 

Densities and ultrasonic velocities of binary mixtures of 2,4,6-trimethyl-1,3,5-trioxane +
n-alcohols at 298.15, 303.15 and 308.15 K

 

149

IPC Code: B01J19/00

 

  N N Wankhede, D S Wankhede, M K Lande & B R Arbad


 

Electro-chemical production of ozone using water electrolysis cell of solid polymer electrolyte (SPE)

 

156

  IPC Code: C25B1/13

 

Sang-Do Han, Jung-Duk Kim, Kwang-Shik Myung, Ravi Kumar Rana & K C Singh

 

 

 

Improved oil recovery using polymeric gelants: A review

162

  IPC Code: C10G21/00

 

  G P Karmakar & Chandrima Chakraborty

 

 

 

Modeling of desilication of green liquor using artificial neural networks

168

IPC Code: B01D3/26

 

S A Mandavgane, S L Pandharipande & D Subramanian

 

 

 

Notes

 

 

 

Application of ANN for modeling of heat exchanger with concentration as variable

173

IPC Code: C09K5/00

 

S A Mandavgane & S L Pandharipande

 

 

 

Improved process for the production of aqueous extract of Vijaysar (Pterocarpus marsupium)

 

177

IPC Code: A61K35/00

 

V K Koul, Suman Koul, C L Tikoo, Anamika Tondon, K L Bedi & R K Raina

 

 

 

Rheology of multigrade engine oils

180

IPC Code: C10M107/00

 

Sabiha Tanveer, Umesh Chandra Sharma & Ram Prasad

 

 

 

Synthesis and analytical application of Fe(III) based heteropoly acid cation exchangers

185

IPC Code: B01J39/00

 

V Geetha & C Janardanan

 

 

 

Chem-Tech Scan

189

 

 

Author Index

193

 

 

Keyword Index

194

 

 

Guidelines for Authors

195

 

 

 

 

 

 

 

 

 

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 107-113

 

Kinetics of palladium catalysed partial oxidation of methane

 

M A Lourdu Antony Raj*, G M Madhu & Y Jagannadha Rao

 

Catalytic partial oxidation of methane to methanol has been investigated in a pressures range of 5-15 kg/cm² and at different temperatures (573-763 K) in quartz-lined reactor using asbestos supported palladium catalyst. The effect of process variables namely, reaction temperature, ratio of the weight of the catalyst to molar flow rate of methane (W/FA0), pressure on conversion of methane and selectivity to reaction products like methanol, carbon dioxide, carbon monoxide were investigated. The kinetic study carried out indicated first order rate for the main reactions. From the effect of temperature on rate constant, activation energy and frequency factors were evaluated. The rate constants are found to be 2.53 and 1.84, activation energies are found to be 186948.60 and 162231.08 for the two main reactions.

Keywords: Partial oxidation, Catalytic oxidation, Methane, Methanol, Palladium

IPC Code: B01J19/00

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 114-118

 

Use of semiconducting iron(III) oxide in photocatalytic bleaching of some dyes

Rajat Ameta, Jitendra Vardia, Pinki B Punjabi & Suresh C Ameta*

 

The biggest consumers of water are textiles, tannery, electroplating and pulp and paper industries and these are also the most serious polluters of environment. Photocatalytic degradation has been considered to be an efficient process for degradation of organic pollutants, which are present in the effluents released by these industries. The photocatalytic bleaching was carried out on cationic dyes (methylene blue, crystal violet, malachite green) in the presence of semiconducting iron(III) oxide and was observed spectrophotometrically. The effect of various operating variables like pH, concentration of dyes, amount of semiconductor, light intensity, particle size, stirring, etc. was also observed on the efficiency of the reaction. A tentative mechanism has also been proposed for this photocatalytic bleaching.

Keywords: Photodegradation, Photocatalytic bleaching, Iron(III) oxide, Methylene blue, Crystal violet, Malachite green

IPC Code: C09B62/00, C09B57/00

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 119-121

 

Immobilization of a-amylase onto alkylamine glass beads affixed inside a plastic beaker: Kinetic properties and application

 

S Dhingra, M Khanna & C S Pundir*

 

Amylase (diastase) from Aspergillus niger has been immobilized through glutaraldehyde coupling onto zirconia coated alkylamine glass beads affixed inside a plastic beaker. The immobilized enzyme retained 10.3% of the initial activity of free enzyme with a conjugation yield of 10 mg/g. Optimum pH, incubation temperature and time for maximum activity, were increased while Km for starch and Vmax were decreased after immobilization. The utility of immobilized enzyme in removal of starch stain from cotton cloth by various commercial detergents was tested by chemical method. All the detergents gave better washing in presence of immobilized amylase than that by detergent alone. Further, the washing by cheaper (non-enzymic) detergents in presence of immobilized amylase was almost similar to that by expensive (enzymic) detergents. The immobilized enzyme was used about 100 times without any considerable loss of activity.

keywords: Amylase, Alkylamine glass, Immobilization, Detergent, Cloth washing, Starch stain

IPC Code: C11D1/00

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 122-127

 

Biosorption of iron(III) from aqueous solutions using the husk of Cicer arientinum

 

N Ahalya, R D Kanamadi & T V Ramachandra*

 

Iron is a major pollutant released as a by-product during several industrial operations especially during acid mining of metal ores. In this paper, the use of Bengal gram husk (husk of channa dal, Cicer arientinum) in the biosorption of Fe(III) from aqueous solutions is discussed. Parameters like agitation time, adsorbent dosage and pH were studied at different Fe(III) concentrations. The adsorption data fit well with Langmuir and Freundlich isotherm models. The adsorption capacity (qmax) calculated from the Langmuir isotherm was 72.16 mg of Fe(III)/g of the biosorbent at an initial pH of 2.5. Desorption studies were performed at different concentrations of hydrochloric acid showing that quantitative recovery of the metal ion is possible. The infrared spectra of the biomass before and after treatment with Fe(III), revealed that hydroxyl, carboxyl and amide bonds are involved in the uptake of Fe(III) ions.

Keywords: Heavy metals, Iron, Biosorption, Langmuir isotherm, Infrared spectra

IPC Code: C02F1/28

 

 

Indian Journal of Chemical Technology

Vol.13, March 2006, pp, 128-134

 

Corrosion inhibition of brass by thiocarbamides

K K Taha, B S Sheshadri, M F Ahmed & V S Muralidharan*

 

Thiocarbamides namely thiocarbamide (TC), ethylenethiocarbamide (ETC) and thiobenzamide (TBA) have been used as corrosion inhibitors for (70/30) brass in 0.1 M HClO4. The inhibitor efficiency (% P) calculated using weight loss, Tafel line extrapolation, linear polarization and impedance methods has been found to be in the order: TBA > ETC > TC. Thiocarbamides adsorbed on the electrode surface inhibited the corrosion of brass. They adsorb following Flory-Huggins isotherms. The number of water molecules displaced was found to increase with molecular size. TC, ETC and TBA displaced 3, 4 and 10 molecules and caused a distortion at the metal solution interface. The inhibitor molecule may form complexes with the dissolved Cu and Zn ions. This may result in the formation of a film.

Keywords: Brass, Corrosion inhibition, Thiocarbamide, Perchloric acid

IPC Code: C23F11/00

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 135-138

 

Acetic acid leaching of magnesia from magnesite via calcination

 

Ayhan Demirbas

 

In this study, magnesite mineral was first calcinated between 800-1100 K for an hour and dissolved in acetic acid solutions. The effects of temperature, solid-to-liquid ratio, reaction time, stirring speed and acid concentration on the dissolution rate of magnesia in acetic acid were investigated. It was observed that the dissolution of magnesia increased with increasing temperature, stirring speed, reaction time and acid concentration and decreased with increase in solid-to-liquid ratio. The dissolution process is controlled by pseudo first-order reaction rate. Activation energy for the reaction was calculated as 8.78 (kJ/mol).

Keywords: Magnesite, Magnesia, Magnesium acetate, Calcination, Dissolution

IPC Code: C04B2/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 139-143

 

Prediction of bed fluctuation ratio for gas-solid fluidization in

cylindrical and non-cylindrical beds

 

R K Singh* & G K Roy

 

Gas flow in a gas-solid fluidized bed is characterized by the predominance of bubbles. This bubbly flow exhibits considerable bed fluctuation at fluid mass velocity higher than the minimum fluidization velocity leading to instability in operation, which affects the fluidization quality adversely. In the present paper, equations have been developed for the prediction of bed fluctuation ratio for gas-solid fluidization in cylindrical and non-cylindrical (viz. semi-cylindrical, hexagonal and square) beds. A fairly good agreement has been obtained between calculated and experimental values. Based on the experiments it is concluded that, under similar operating conditions bed fluctuation ratio is maximum in case of square bed and it is least in case of semi-cylindrical bed. The fluctuation ratio becomes maximum at a particular velocity ratio Gf /Gmf, for a particular bed and then it either decreases (due to slug formation) or remains constant at higher velocity ratio thereafter. It has also been observed that transformation from bubbling to slugging mode was latest in case of semi-cylindrical bed and earliest in case of a square one, thus providing a larger span of effective gas-solid fluidization in the bubbling regime in a semi-cylindrical bed as compared to other non-cylindrical and cylindrical beds.

Keywords: Gas-solid fluidization, Bed fluctuation ratio, Non-cylindrical bed

IPC Code: B01J8/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 144-148

 

Holdup measurement in a gas-liquid ejector for a sodium chloride-air system

 

P T Raghuram* & T R Das

 

Holdup measurements have been carried out experimentally using gamma ray attenuation method in a gas liquid ejector for a sodium chloride-air system. The measured values are compared with the theoretically predicted values based on feed calculations. Holdup as a function of the liquid flowrate and also its distance from the nozzle of the ejector has been reported in this paper. The results obtained for this non-reactive system are also compared with those of air-water system.

Keywords: Holdup measurement, Ejector, Radiological method, Gamma ray attenuation, Non-reactive system

IPC Code: F04B47/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 149-155

 

Densities and ultrasonic velocities of binary mixtures of

2,4,6-trimethyl-1,3,5-trioxane + n-alcohols at 298.15, 303.15 and 308.15 K

 

N N Wankhede, D S Wankhede, M K Lande & B R Arbad*

 

The densities and ultrasonic velocities of binary mixtures of 2,4,6-trimethyl-1,3,5-trioxane + ethanol, 1-propanol and 1-butanol at 298.15, 303.15 and 308.15 K were measured over the whole mole fraction range. Experimental data were used to estimate isentropic compressibility (ks), intermolecular free length (Lf), specific acoustic impedance (Z) and their deviations, such as deviation in isentropic compressibility (Dks), excess intermolecular free length (LfE) and excess acoustic impedance (ZE). The results are fitted to a Redlich-Kister equation. The results are discussed in terms of molecular interactions.

Keywords: Ultrosonic velocities, Binary mixtures, n-Alcohols, 2,4,6-Trimethyl-1,3,5-trioxane

IPC Code: B01J19/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 156-161

 

Electro-chemical production of ozone using water electrolysis cell of solid polymer electrolyte (SPE)

 

Sang-Do Han, Jung-Duk Kim, Kwang-Shik Myung, Ravi Kumar Rana & K C Singh*

 

A new method for the preparation of anode electro-catalyst for O3 production in water electrolysis cell using solid polymer electrolyte has been described. The current voltage curves at different temperatures are discussed. The ozone production efficiency is found to be maximum at current density around 1.5 amp/cm2 at temperature around 25°C.

Keywords: Nafion membrane, Overvoltage, Current efficiency, O3 production, Electrolysis

IPC Code: C25B1/13

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 162-167

 

Improved oil recovery using polymeric gelants: A review

 

G P Karmakar* & Chandrima Chakraborty

 

Oil and gas production from the reservoirs are often accompanied by huge amount of water production. Excessive water production from the oil and gas reservoirs is one of the major problems faced by the petroleum industries worldwide. Polymers and gels have been successfully used for many years to control the water production. Most methods involve cross-linked polyacrylamide gels initiated by metal ions or organic radical formation. Some inorganic compounds, particularly Fe(III) compounds can be transformed to gels by in-situ hydrolysis, which can be effectively used as the blocking materials. A new type of organically modified silicate compound, tetramethoxysilane (TMOS) has been supposed to be more effective in water shut-off jobs. In-situ cross-linking acid diverting agents (ISCADA) is proved to be a better solution to stimulate the multi-layered reservoirs. Certain biopolymers and foams may also be used successfully to control water production in oil or gas reservoirs. This paper attempts to review the present status of the gel systems used in the oil industries to control the water production during oil and gas production.

 

Keywords: Tetramethoxysilane, Polymeric gelant

IPC Code: C10G21/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 168-172

 

 

Modeling of desilication of green liquor using artificial neural networks

S A Mandavgane*, S L Pandharipande & D Subramanian

 

In the recovery section of pulp and paper mill the smelt from the furnace is dissolved in water, the green coloured solution is called as green liquor. The green liquor obtained from paper mills using agricultural residues as raw material contains silica. This silica interferes in every stage of recovery section. Desilication of green liquor is essential as it restricts silica entry into the downstream units and silica re-entry through recovered and recycled digester chemicals. In present work, multi layer perceptron (MLP) ANN with GDR based learning have been developed for estimation of silica concentration and degree of desilication as a function of pH and time. The numbers of neurons and hidden layers were varied to get the most accurate ANN model. The ANN models thus developed with three hidden layers were found to be of good accuracy level, both for training and test data set.

Keywords: Green liquor, Carbonation, Pulp and paper mills, Artificial neural networks (ANN)

IPC Code: B01D3/26

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 173-176

 

Application of ANN for modeling of heat exchanger with concentration as variable

S A Mandavgane* & S L Pandharipande

 

Artificial Neural Networks (ANN) are effective in modeling of non-linear multi variable relationships and also referred to as black box models. Generally, for modeling of heat exchangers the various parameters to be taken into account are inlet and outlet temperatures of shell, tube side fluids, and their flow rates. In the present paper, the concentration of flowing fluids is also considered as one of the variable parameters for heat exchanger modeling. For the study three different fluids are used, (i) water, (ii) 20% glycerin and (iii) 40% glycerin. Heat exchanger model is developed using optimized ANN architecture1. ANN model is trained using a water-water2 and water-40% glycerin3 system. The trained networks are then used for prediction of shell and tube side exit temperatures for water-20% glycerin3 system. It is observed that predicted values of water–20% glycerin system are in close agreement (98-99%) with the actual values.

Keywords: Artificial neural networks (ANN), Shell and tube heat exchanger, Modeling

IPC Code: C09K5/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 177-179

 

Improved process for the production of aqueous extract of Vijaysar (Pterocarpus marsupium)

 

V K Koul*, Suman Koul, C L Tikoo, Anamika Tondon,
K L Bedi & R K Raina

 

An improved process for the production of aqueous dry extract of Vijaysar (Pterocarpus marsupium) has been developed on pilot scale (100 kg batch capacity). The new process takes only 18 h as compared to 72 h of the conventional process. The energy consumed is 1/3 of the old process and yield of Vijaysar using the new process improved by 2 to 2.5%. At the same time no change was observed in the quality of the final product with respect to hypoglycaemic activity, HPLC profile and other standard quality parameters.

Keywords: Pterocarpus marsupium, Vijaysar, Improved process

IPC Code: A61K35/00

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 180-184

 

Rheology of multigrade engine oils

 

Sabiha Tanveer, Umesh Chandra Sharma & Ram Prasad*

 

Rheology of multigrade engine oils, SAE 15W-40, SAE 20W-40, SAE 20W-50 and SAE 25W-50 has been examined experimentally in the temperature range of -20 to 20°C. Experiments have been carried out to observe the dependence of shear rate, time and temperature on the apparent viscosity of these multigrade engine oils. The oils SAE 15W-40 and SAE 20W-40 are found to behave as Newtonian fluids above a temperature of about 5°C. The oils SAE 20W-50 and SAE 25W-50 are found to behave as Newtonian fluids above a temperature of about 10°C. Below these temperatures, they behave as dilatant fluids. These oils also exhibit a rheopectic behaviour. The apparent viscosity of these multigrade engine oils decreases with increase in temperature.

Keywords: Rheology, Multigrade engine oil, Viscosity, Shear rate

IPC Code: C10M107/00

 

 

Indian Journal of Chemical Technology

Vol. 13, March 2006, pp. 185-188

 

Synthesis and analytical application of Fe(III) based heteropoly acid cation exchangers

 

V Geetha & C Janardanan*

 

New inorganic ion exchangers based on Fe(III) namely ferric tungstomolybdate, ferric tungstosilicate, ferric tungstovanadate have been synthesized and characterized on the basis of chemical composition, ion exchange capacity, pH titrations, distribution coefficients, FTIR, TGA and thermal stabilities. The ion exchangers were found to be stable in 1.0 M mineral acids and 1.0 M metal chloride solutions. The formulae proposed for the exchangers are Fe2O3.2WO3.2MoO3.8H2O; Fe2O3.2WO3.2SiO2.9H2O and Fe2O3.2WO3.V2O5.10H2O respectively. Based on the difference in Kd values, some analytically important separations of metal ions have been achieved. The important mixtures analyzed are Al3+ - Mg2+, Co2+- Pb2+, Hg2+ - Pb2+, Ni2+- Pb2+, Cd2+ - Pb2+ and Cu2+ - Pb2+.

Keywords: Ion exchangers, pH Titration, Ion exchange capacity, Distribution coefficient

IPC Code: B01J39/00