Indian Journal of Chemical Technology

VOLUME 8

NUMBER 3

MAY 2001

 

CONTENTS

 

Continuous ethanol production by fermentation of waste banana peels using floccula­ting yeast

153

                        S S Joshi, Rahul Dhopeshwarkar, Unmesh Jadhav, Rishikesh Jadhav, Lawrence D’souza & Jayaprakash Dixit

 

Control of mesoporosity in alumina

157

                        Manoj Kumar, Babu Lal, Anand Singh, A K Saxena, V S Dangwal, L D Sharma & G Murali Dhar

 

Vapour phase catalytic transformations of 3-carene over impregnated zeolites: Influence of organic bases

162

                        V Krishnasamy & M Eswaramoorthy

 

Characterization and catalytic activity of Ni-W/SiO2-Al2O3 hydrocracking catalysts

169

                        L D Sharma, Manoj Kumar, J K Gupta, M S Rana, V S Dangwal & G Murali Dhar

 

Studies on epoxidised oil and its blend with polystyrene and poly(methyl methacrylate)

176

                        Sharif Ahmad, S M Ashraf, Abul Hasnat & Azeem Noor

 

 

Mechanical and electrical properties of polyimide blend films

181

                        Sohan Niyogi, Sukumar Maiti & Basudam Adhikari

 

 

Adsorption of Cr(IV) onto Wollastonite: Effect of pH

186

                        Y C Sharma

 

Simultaneous determination of mefenamic acid and paracetamol in pharmaceutical preparation by 1H-Nuclear Magnetic Resonance Spectroscopy

191

                        Sajid Husain, M Kifayatullah & R Sekar

 

Stability of allicin in garlic¾A kinetic study

195

                        Rashmi Mishra, S K Upadhyay & P N Maheshwari

 

 

Spectrophotometric determination of manganese(II) by picolinaldehyde nicotinoyl-
hydrazone

200

                        R B Pawar, S B Padgaonkar & A D Sawant

 

 

Preparation and characterization of cathode catalysts for molten carbonate fuel cells

204

                        G Prabhu, S Dheenadayalan, I Arun Raj, R Chandrasekaran & R Pattabiraman

 

 

Flotation-separation of the pollutant species of chromium, cadmium and lead from aqueous solutions and natural waters

211

                        S E Ghazy, M A Kabil, A M Shallaby & N S Ammar

 

Vehicular pollution control-rennoval of carbon monoxide through catalytic converters

219

                        Anurag Garg & Shri Chand

 

Acid cleaning operation for a natural circulation high pressure drum boiler unit of a thermal power station

223

                        M Azad Sohail & A Ismail Mustafa

 

ANN Controller trained with steady state input-output data for a heat exchanger

227

                        M S Dasgupta, G B Menon & R K Gupta

 

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp 153-156

 

 

Continuous ethanol production by fermentation of waste banana peels using flocculating yeast

S S Joshi*, Rahul Dhopeshwarkar, Unmesh Jadhav, Rishikesh Jadhav, Lawrence D’souza & Jayaprakash Dixit

Department of Chemical Engineering, Tatyasaheb Kore Institute of Engineering and Technology, Warananagar,
Kolhapur 416 113, India

Received 26 June 2000; accepted 18 January 2001

Warana Agricultural Goods Processing Co-operative Society (WAGPCOS), a unit producing banana puree at Amritnagar gives out the banana peels along with the foul bananas as a major waste. This waste was tested for its sugar content and was found to contain substantial amount of sugars with hardly any hazardous material for the fermentative microorganisms i.e. yeast. To utilize this waste as a fermentation substrate, extract was prepared from the waste. Highly flocculant yeast Saccharomyces uvarum (NCIM culture 3528) having a high fermentation activity was used for the fermentation. A multi vessel system was prepared for the fermentation of waste extract. The system consisted of a main reactor, a buffer vessel and a separation vessel. The fermentation was carried out under anaerobic conditions with CO2 bubbling and well maintained pH and temperature. Runs were carried out at different feed rates with continuous yeast cell recycle. It was observed that the waste banana peels are capable of providing enough sugar for the fermentation and hence can be economically utilized for the ethanol production. After the removal of the extract from the waste, the remaining fibrous material can be dried in an easier way and can prove to be a good fodder for the animals.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 157-161

 

 

Control of mesoporosity in alumina

Manoj Kumar*, Babu Lal, Anand Singh, A K Saxena, V S Dangwal, L D Sharma & G Murali Dhar

Catalysis laboratory, Indian Institute of Petroleum, Dehradun 248 005, India

Received 08 May 2000; accepted 05 January 2001

The textural properties of the alumina carrier play a major role in governing the performance of alumina based heterogeneous catalysts. The regulation of the pore size distribution in the support is of paramount importance in the development of a promising catalyst. The role of peptising agent, combustible additives and binder in regulating the mesoporosity has been investigated using high pressure mercury porosimetry. Control of pore size in 18-50Å radii range can be achieved by peptising alumina monohydrate (boehmite) by 1.5% nitric acid. Additives like polyvinyl alcohol and polyethylene glycol have broadened the mesopores while carbon black has drastically increased pores in 50-100 Å range. Addition of 10% calcined alumina as binder has been found suitable to maintain pores <50 Å radii.

 

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 162-168

 

 

Vapour phase catalytic transformations of 3-carene over chromium impregnated zeolites : Influence of organic bases

V Krishnasamy* & M Eswaramoorthy

Department of Chemical Technology, Anna University, Chennai 600 025, India

Received 21 March 2000; accepted 27 December 2000

Large pore zeolites, 13X and Y and medium pore zeolite ZSM-5 were synthesised by hydrothermal method, partially converted them into H-form by ion exchange. Each was impregnated with 2% Cr and they were characterised by physico-chemical analysis.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 169-175

 

 

Characterization and catalytic activity of Ni-W/SiO2-Al2O3
hydrocracking catalysts

L D Sharma*, Manoj Kumar, J K Gupta, M S Rana, V S Dangwal & G Murali Dhar

Catalysis Laboratory, Indian Institute of Petroleum, Dehradun 248 005, India

Received 19 June 2000; accepted 21 January 2001

Characterization of Ni-W SiO2-Al2O3 catalysts was carried out by microcalorimetry, TPR and oxygen chemisorption. The effect of incorporation of individual metals and their sequence of addition to the support on the properties and catalytic activity for cyclohexene hydrogenation and cumene cracking was investigated. While the addition of nickel to SiO2-Al2O3 has little effect on the acidity, tungsten has generated some new strong acid sites, which do not seem to have beneficial effect for cumene cracking. Low temperature TPR peak in the bimetallic catalysts falls around 760 K due to Ni-W species while the high temperature peak around 1115-1223K corresponds to W species. W/SiO2-Al2O3 has a lower oxygen chemisorption than its nickel counterpart but has a higher hydrogenation rate. Tungsten is the active metal for hydrogenation. W-Ni/SiO2-Al2O3 catalyst has better hydrogenation and cracking activity.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 176-180

 

 

Studies on epoxidised oil and its blend with polystyrene and
poly(methyl methacrylate)

Sharif Ahmad*, S M Ashraf, Abul Hasnat & Azeem Noor

Materials Research Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110 025, India

Received 21 September 2000; accepted 7 February 2001

Attempts have earlier been made to replace aromatic epoxies by renewable resource based vegetable oil epoxies. However the latter lack in toughness and strength. To improve these properties linseed oil epoxy was blended with polystyrene and poly(methyl methacrylate). The polyblends were prepared in varying proportion of oil epoxy and polystyrene/poly(methyl methacrylate), for investigation of their physical and mechanical characteristics with reference to their use in coatings. The blend formation was confirmed by DSC, FT-IR and solution tests. The epoxy equivalent, hydroxyl value, iodine value, viscosity, refractive index, and specific gravity of oil epoxy, oil epoxy -polystyrene blends and oil epoxy-poly(methyl methacrylate) blend were determined. Glass transition temperatures of linseed oil epoxy-polystyrene blends were found to occur in the range of 60-77.6°C and for the linseed oil epoxy-poly(methyl methacrylate) blends in the range of 75-82.4°C in the composition range investigated. Distinct shift in IR peaks of epoxy ring, ester group and hydroxyl group was observed in both the polyblends systems indicating electrostatic interaction between the constituents of the blends. Linseed oil epoxy was found to turn into rigid mass by the addition of these polymers to the extent of only 16.6% (w/w). Preliminary investigations also revealed higher toughness and rigidity in linseed oil epoxy-poly(methyl methacrylate) blends than in linseed oil epoxy polystyrene blends. Both the polyblends systems show solubility in various organic solvents.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 181-185

 

Mechanical and electrical properties of polyimide blend films

Sobhan Niyogi, Sukumar Maiti & Basudam Adhikari*

Materials Science Centre, Indian Institute of Technology, Kharagpur 721 302, India

Received 17 November 1999; accepted 28 November 2000

The preparation and characterization of two novel polyimide, one from pyromellitic dianhydride (PMDA)-4,4¢-oxydianiline (ODA) and the other from 3,3¢, 4,4¢-benzophenone tetracarboxylic dianhydride (BTDA)-ODA, blend films with nylon 6 were reported earlier1,2. PMDA-ODA and nylon 6 blend films have shown up to 14.7 % increase in Young’s modulus and 25 % increase in tensile strength at lower elongation over those of control films, whereas the same films have shown around 4.6 % decrease in ultimate tensile strength (except the film PB 2 which shows about 1 % increase in ultimate tensile strength). BTDA-ODA and nylon 6 blend films have shown 19 % higher ultimate tensile strength as well as 42 % higher Young’s modulus and 47 % higher tensile strength at lower elongation. But in general the dielectric constant of the blend films (both BTDA and PMDA based) measured at 23°, 100° and 200°C and at 1,5 and 10 kHz frequency increases with increase in the percentage of nylon 6 in the blend and the breakdown voltage decreases with the increase in nylon 6 content in the blend films.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 186-190

 

 

Adsorption of Cr (VI) onto Wollastonite: Effect of pH

Y C Sharma

Environmental Engineering and Research Laboratories, National Institute of Foundry and Forge Technology,
Hatia Ranchi 834 003, India

Received 29 May 2000; accepted 12 February 2001

Wollastonite, a clay mineral has been investigated for the adsorption of  Cr(VI). Adsorption of chromium was studied as a function of pH and 2.0,5.0,6.0 and 8.0 pH were selected for studies. Maximum adsorption was found (74.4%)  at pH 2.0, temperature 30oC, 0.5´10-4M Cr(VI) concentration, 0.01 M NaClO4 ionic strength and 100 rpm of agitation speed. It was, however, minimum (12.3%), at pH 8.0. Equilibrium time of adsorption was independent of pH values. Different possible explanations have been discussed for removal or Cr(VI) for the present system. Kinetics of the removal of Cr(VI) at various pH values has been discussed and rate constant of the adsorption has been determined.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 195-199

 

 

Simultaneous determination of mefenamic acid and paracetamol in pharmaceutical preparations by 1H-Nuclear Magnetic
Resonance Spectroscopy

 

Sajid Husain, M Kifayatullah & R Sekar*

Analytical Chemistry Division, Indian Institute of Chemical Technology, Hyderabad 500 007, India.

Received 02 May 2000; accepted 17 January 2001

A simple, specific and rapid nuclear magnetic resonance (NMR) spectroscopic method for the determination of mefenamic acid and paracetamol in pharmaceutical preparation is described. Samples are dissolved directly in DMSO-d6 and their spectra are recorded on a Gemini-200 MHz NMR spectrometer instrument. The results obtained by the proposed method is agreed closely with those found by the method of British Pharmacopoeia (BP). No interference due to excipients is also observed.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 191-194

 

Stability of allicin in garlic—A kinetic study

Rashmi Mishraa,  S K Upadhyaya* & P N Maheshwarib

aDepartment of Chemistry

bDepartment of Biochemical Engineering & Food Technology, H B Technological Institute, Kanpur  208 002, India

Received 30 June 1999; accepted 22 November 2000

In order to study the stability of allicin, an active constituent of garlic extract, the rate of formation of allicin from allicin and that of decomposition of allicin to volatile oil/sulphides has been determined by chloramine—T method. The effect of acetic acid (5-30%), ethanol (5-30%), buffers (pH 4.0-6.0) and temperature (30-50°C) on the rate of formation of allicin and on the rate of its further decomposition to volatile oil has been studied. It has been observed that the decomposition of allicin decreases with an increase in the strength of acetic acid and increases with an increase in the pH of macerating medium. The increasing strength of ethanol in macerating medium had a little effect of the rate of decomposition, which was found to be maximum at an incubation temperature of 35°C.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 200-203

 

Spectrophotometric determination of manganese(II) by picolinaldehyde nicotinoylhydrazone

R B Pawar, S B Padgaonkar & A D Sawant*

Inorganic Chemistry Division, The Institute of Science, 15, Madam Cama Road, Mumbai 400 032, India

Received 07 December 1999; accepted 18 January 2001

Manganese (II) forms a yellow coloured complex with a reagent picolinaldehyde nicotinoylhydrazone (PANH), which can be quantitatively extracted into chloroform in the pH range 8.7-10.5. Beer’s law was obeyed over the concentration range of 0.02-1.5 ppm with absorption maxima at 385 nm. The molar absorptivity and Sandell’s sensitivity of the extracted species was found to be 4.606 ´ 104 L mol–1 cm–1 and 1.19 ng cm–2 respectively. The nature of the complex was determined by different methods and it was found to be 1:2 (Metal: Ligand). Interference due to diverse ions has been studied. The proposed method is simple, rapid, accurate, sensitive and has been applied for separation and determination of Mn(II) in synthetic mixtures and real samples.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 204-210

 

 

Preparation and characterization of cathode catalysts for
molten carbonate fuel cells

G Prabhu, S Dheenadayalan, I Arul Raj, R Chandrasekaran & R Pattabiraman

Central Electrochemical Research Institute, Karaikudi 630 006, India

Received 19 April 2000; accepted 27 December 2000

Three different methods were adopted to prepare the lithiated nickel oxide cathodes for Molten Carbonate Fuel Cell (MCFC). In the first method Ni electrodes with desired porosity were prepared and oxidized and lithiated inside the cell (in-situ method). Loose powder sintering, slurry casting and tape casting methods were followed to prepare the electrodes. In the second method, out of cell oxidation and lithiation of nickel powder was carried out by mixing nickel powder with lithium carbonate followed by oxidation in air at 650o C (ex-situ method) and then formed into the electrodes. In the third method, the pre-lithiated nickel catalyst was formed into an electrode by tape casting technique and the electrodes were subjected to in cell or out of cell oxidation and sintering. The physico-chemical characterization of the catalyst and the electrodes were obtained by XRD and mercury porosimetry respectively. The performance of the electrodes was evaluated in single cell MCFC with 45 cm2 area electrodes at 650oC.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 211-218

 

 

Flotation-separation of the pollutant species of chromium, cadmium and lead from aqueous solutions and natural waters

S E Ghazya, M A Kabila, A M Shallabya & N S Ammarb

aChemistry Department, Faculty of Science, Mansoura University, P.O. Box 66, Mansoura, Egypt

bWater Pollution Department, National Research Centre, Dokki, Giza, Egypt

Received 13 July 2000; accepted 18 January 2001

Simple, rapid and accurate procedures have been presented for removing the pollutant species of chromium, cadmium and lead from different aqueous media. To achieve this goal, precipitate flotation was the method of choice for this investigation using oleic acid (HOL) as a surfactant. Cr(III) as its hydroxide and Cr(VI) as Ag2CrO4 or Ag2Cr2O7 are removed in the pH ranges 6.2-6.8 and 6.0-7.5, respectively. 2,4,6-Tri(2-pyridyl)-1,3,5-triazine (TPTA), in the presence of KI, and chloranilic acid (CAA) are found to be the most effective complexing agents for the flotation of trace amounts of Cd(II) and Pb(II) over the pH ranges 6-7.5 and 4-7, respectively. The effects of surfactant and analyte concentrations, foreign ions and temperature have been examined. The application of these procedures to recover the analytes added to natural water samples has been investigated. Since the system Cr(VI)/Cr(III) is toxic, it occurs in industrial effluents and some natural waters, a procedure for the selective separation of Cr(VI) from Cr(III) is suggested as a useful tool for speciation studies. Moreover, the flotation mechanism is proposed.

 

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 219-222

 

 

Vehicular pollution control- removal of carbon monoxide through catalytic converters

Anurag Garg & Shri Chand*

Department of Chemical Engineering, University of Roorkee, Roorkee 247 667, India

Received 28 February 2000; accepted 15 January 2001

In an attempt to find a substitute to noble-metal based catalysts in the catalytic converters for the removal of CO from automotive exhaust, non-noble metal based catalysts of perovskite based oxides were tested. Perovskites of the structure ABO3, where A cation had La , Ba or Ca and B cation had Co or Fe were used for the reaction. Substituted perovskite of the form A1-xA¢xBO3, where A¢ was Ce metal, was also used. The perovskite catalyst were tested in unsupported as well as supported forms. The supports used were zirconia, ceria or a mixture of the two in different proportions. The results indicate that among the unsupported catalysts, LaCoO3 is the best. Among the substituted catalysts, La0.3Ce0.7CoO3 gave the best performance showing 100% CO conversion at 200°C. The support, zirconia (20%) and ceria (80%) mixture was found to be the best combination. The durability runs up to 6 h show the activity pattern in the order : La0.3Ce0.7CoO3> La0.6Ce0.4CoO3 > LaCoO3.

 

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 223-226

 

 

Acid cleaning operation for a natural circulation high pressure drum boiler unit of a thermal power station

M Azad Sohail*a & A Ismail Mustafab

aCentral Chemical Research Laboratory, Ghorsal Thermal Power Station, BPDB, Narsingdi, Bangladesh

bDepartment of Applied Chemistry and Chemical Technology. University of Dhaka, Dhaka-1000, Bangladesh

Received 29 March 2000; accepted 2 February 2001

Two-stage acid cleaning (TSAC) operation has been employed and investigated to clean up undesired impurities (deposit) in boiler water wall tubes (BWWT), boiler drum, super heater, economizer, feed water lines, live steam lines, hot reheat lines, cold reheat lines, dearator, collectors, headers for a natural circulation high pressure drum boiler unit, TGME - 206–COB, Russia (158 kGf cm–2, capacity steam generation 670 ton h–1, 210 MW unit) of a thermal power station in Bangladesh. The deposit and loose impurities consist of Fe2O3, CaO, MgO and SiO2. On area basis the maximum quantity (98g –2) of deposit was measured at boiler WWTs. During cleaning operation the loose impurities were withdrawn at first by flashing of the water. TSAC operation was carried out at two stages by re-circulation of hot 105 (± 5° C) cleaning solution H2SO+ N2H4.H2O (250 ± 25 mg L–1) at pH 2.0 (± 0.5) for 24 h. The TSAC operation revealed that not less than 95% of impurities were removed. The cleaning mechanism and passivation on clean surface of tubes by circulation of 500 mg L–1 N2H4 and 0.4% NH4OH with pH 10.8 (± 2) at 60° C were found to be satisfactory.

Indian Journal of Chemical Technology

Vol. 8, May 2001, pp. 227-234

 

 

 

ANN controller trained with steady state input-output data for a heat exchanger

M S Dasguptaa, G B Menonb & R K Guptac

aMechanical Engineering Group, Birla Institute of Technology & Science, Pilani 333 031, India

bR&D Group, Tata Iron & Steel Company, Jamsedpur, India

cChemical Engineering Group, Birla Institute of Technology & Science, Pilani 333 031, India

Received 17 May 2000; accepted 12 February 2001

This paper discusses the design and implementation of an Artificial Neural Network (ANN) based adaptive controller for a heat exchanger. The control strategy chosen is that of explicit nonlinear model predictive control. The nonlinear inverse model of the plant is identified from steady state input-output data by off-line training of a multilayered neural network through error back propagation. For performance enhancement, manipulation of training data and on-line parameter updating are tried. Single pass of derivative of error measure across the plant, on-line gave an excellent performance for regulatory as well as servo problem. The proposed controller is found to be successful over a wide operating range. The results are compared with that of an optimized PID controller.