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Indian Journal of Chemical Technology

 

 

 

ISSN:0971-457X

 

CODEN:ICHTEU 11(5) 601-750

VOLUME 11

NUMBER 5    

SEPTEMBER 2004

 

 

CONTENTS

 

Research Articles

 

 

 

Decolourization of pulp and paper mill effluent using polyvinyl chloride 

607

IPC Code: C02 F 1/28, 103:28

 

Shivani Bhardwaj & Mukhtar A Khan

 

 

 

Effect of salt additives on decolouration of Acid Black 1 dye effluent by ozonation

612

IPC Code: C02 F 1/28, C09 B 62/60

 

M Muthukumar, D Sargunamani, N Selvakumar & D Nedumaran

 

 

 

Colour removal of pulp and paper effluents                                

617

IPC Code: C02 F 1/28, 103:28

 

B Chakradhar & Sonia Shrivastava

 

 

 

Decolourization of synthetic dyes using rice straw attached Pleurotus ostreatus    

622

IPC Code: C09 B 57/00 (C02 F 1/28, 101:30, 103:30)

 

R Neelamegam, V Baskaran, R Dhanasekar & T Viruthagiri

 

 

 

Preservation of bagasse by an alternative cost-effective and eco-friendly approach          

626

IPC Code: B27 K 9/00

 

K R Yadav, A B Chaudhari, R K Sharma & R M Kothari 

 

 

 

Indirect spectrophotometric determination of some biologically important phenothiazines using potassium dichromate, iron(II) and 1,10-phenanthroline

632

IPC Code: C07 D 279/00, G01 J 3/00

 

K Basavaiah

 

 

 

Application of aliovalency effect in the processing of refractory minerals

639

IPC Code: C04 B

 

Ashok N Gokarn, Swati S Kulkarni & Anita R Pande

 

 

 

Transport of uranyl ion (UO22+) across bulk liquid membrane by theonyl trifluoro acetone (TTA)

643

IPC Code: B01 D 61/38, C22 B 60/02

 

D Nanda, H P S Chauhan & B Maiti

 

 

 

Total gas analysis of nuclear fuels                                                     

648

IPC Code: G21 C

 

Y Sesha Sayi, C S Yadav, P S Shankaran & G C Chhapru 

 

 

 

Some physical and chemical properties of ostrich skins and leathers 

654

IPC Code: G01 N 33/44

 

Behzat Oral Bitlisli, Bahri Basaran, Ozcan Sari, Ahmet Aslan & Gokhan Zengin

 

 

 

Enzyme technology applications in leather processing                        

659

IPC Code: C14 B 1/00

 

R B Choudhary, A K Jana & M K Jha

 

 

 

Evaluation of corrosion inhibition by cerium on aluminium under marine and laboratory environments   

 672

IPC Code: C23 F 11/00

 

Muhamed Ashraf P & Leela Edwin

 

 

 

Ethylation of benzene over AFI type molecular sieves                       

678

IPC Code: C07 C 15/04, C01 B 39/54

 

K Joseph Antony Raj & V R Vijayaraghvan

 

 

 

Zeolite supported iron catalyst for nitric oxide reduction by ammonia in the presence of oxygen

683

IPC Code: C01 B 21/24, B01 J 29/064

 

A V Salker

 

 

 

Synthesis of glycylcalix[6]arene and its applicability as resin for separation and preconcentration of trace transition metals             

 688

IPC Code: G01 N 33/44

 

H Bhatt & Y K Agrawal

 

 

 

Studies of metal ion uptake behaviour of formaldehyde condensed resins of phenolic Schiff bases derived from the reaction of 4,4’-diaminodiphenyl and 4,4’-diaminodiphenylmethane with o-hydroxybenzeldehyde   

695

IPC Code: C08 G 8/10, G01 N 33/44

 

R K Dey, S Acharya, S Samal & A R Ray

 

 

 

Determination of micropore volume and surface area of zeolite molecular sieves by D-R and D-A equations: A comparative study 

704

IPC Code: B01 J 29/04

 

Raj K Vyas, Shashi & Surendra Kumar

 

 

 

Molecular interactions in binary liquid mixtures of dimethylsulphoxide with chloroethanes and chloroethenes                                         

710

IPC Code: G01 F

 

M Radhamma, K Sivakumar & M V P Rao

 

 

 

Evaluation of apparent and partial molar volume of potassium ferro- and ferricyanides in aqueous alcohol solutions at different temperatures

 714

IPC Code: G01 N 9/00, C01 C 3/12

 

U N Dash, G S Roy & S Mohanty

 

 

 

A generalized correlation of nucleate pool boiling of liquids 

719

S Bhaumic, V K Agrawal & S C Gupta

 

 

 

Notes                 

 

 

 

Chromatoghaphy of heavy metal cations with formic acid containing mobile phases:  Effect of added organic solvents and surfactants on the mobility of cations     

726

IPC Code: B01 D 15/08

 

Ali Mohammad & Yasir Hamid Sirwal

 

 

 

Educator

 

 

 

Phlogiston: The rise and fall of a theory        

732

Jaime Wisniak

 

 

 

Chem-Tech Scan  

745

 

 

Author Index 

749

 

 

Keywords Index  

750

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 607-611

 

Decolourization of pulp and paper mill effluent using polyvinyl chloride

 Shivani Bhardwaj & Mukhtar A Khan*

 

Decolourization of pulp and paper mill wastewater better known as black liquor using low cost adsorbents is under investigation over the years. Colour of the black liquor is aesthetically harmful to the environment as it contains certain toxic and xenobiotic compounds. Polyvinyl chloride (PVC) is water insoluble, low crystalline polymer and cost friendly. Alkalies and acids present in wastewater do not affect the basic structure of this linear macromolecule. Physicochemical method for decolourization was adopted for process simplification. Contact-time, effect of dosages, adsorption dynamics and adsorption isotherms were few parameters examined for the study. Moderate to fair results were obtained rendering PVC as a substitute to some high-cost polymers used as adsorbents. The probable interactions between chromophoric components of black liquor and PVC has been discussed.

 

IPC Code: (C02 F 1/28, 103:28)

Keywords: Decolourization, paper mill effluent, polyvinyl chloride, black liquor, FTIR

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 612-616

 

Effect of salt additives on decolouration of Acid Black 1 dye effluent by ozonation

M Muthukumar*, D Sargunamani, N Selvakumar & D Nedumaran

 

An attempt was made to study the effect of presence of inorganic salts namely, sodium carbonate, sodium chloride and sodium sulphate, and their concentrations on decolouration of acid dye effluent by ozonation. Studies have been conducted at different salt concentrations and at alkaline pH on Acid Black 1 dye effluent, having a concentration of 500 µM. It has been found that salt content in the effluent increases the decolouration time of the acid dye effluent. Higher the salt content more is the decolouration time and among the salts, sodium carbonate requires more time for complete decolouration than the sodium chloride and sodium sulphate. Chemical oxygen demand (COD) reduces by 52, 58 and 62% whereas total organic carbon (TOC) reduces by 28, 32 and 33% for the salt present in the effluent, namely sodium carbonate, sodium chloride and sodium sulphate respectively. IR spectra study confirms the formation of acidic by-products during ozonation.

 

IPC Code: C02 F 1/28, C09 B 62/60

Keywords: Ozone, acid dye, inorganic salt, colour removal, COD, TOC

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 617-621

 

Colour removal of pulp and paper effluents

 B Chakradhar* & Sonia Shrivastava

 

The paper industry requires large volumes of process water of high purity and generate equally large volumes of waste water from digestion process, which is highly coloured. The removal of colour from paper mill waste water is one of the major environmental problems, because of the difficulty of treating such water by conventional methods. The present study was undertaken for removal of colour from paper mill effluents using waste sludge from ETP as an adsorbent, with heat treatment. The operating variables studied were effluent concentration, adsorbent dosage and contact time.

 

IPC Code: (C02 F 1/28, 103:28)

Keywords: Adsorption, ETP sludge, coloured effluent, contact time and heat treatment

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 622-625

 

Decolourization of synthetic dyes using rice straw attached pleurotus ostreatus

R Neelamegam, V Baskaran*, R Dhanasekar & T Viruthagiri

 

Preliminary studies were conducted to assess the degree of decolourization of different dyes such as Malachite green, Indigo carmine, Xylidine ponceau, Bismark brown, Congo red and Methyl orange using the white rot fungus Pleurotus ostreatus. The effect of initial concentration of different dyes on the decolourization was studied. The effect of pH and biomass concentration during decolourization were also observed for all the dyes. The time course of decolourization was also characterised for all the dyes at their optimum concentrations. An improved percent decolourization [95%] was achieved for Xylidine ponceau, Methyl orange, Congo red and Bismark brown with the rice straw attached Pleurotus ostreatus.

 

IPC Code: C09 B 57/00 (C02 F 1/28, 101:30, 103:30)

Keywords: Synthetic dye, rice straw, Pleurotus sp., decolourization

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 626-631

 

Preservation of bagasse by an alternative cost-effective and eco-friendly approach

K R Yadav, A B Chaudhari, R K Sharma & R M Kothari*

 

A practicable, cost-effective and eco-friendly protocol of bagasse preservation for six months has been evolved. It envisages exposure of 4 ppm ozone once per month on 200 kg bagasse covered with polythene sheet. It afforded substantial (87%) reduction of bacterial, fungal and yeast count, concomitantly retaining initial properties of fiber, largely arresting degradation of cellulose and hemi-cellulose content and thereby maximally retaining initial brightness (reduction by meager 5.7%).

 

IPC Code: B27 K 9/00

Keywords: Bagasse preservation, ozone exposure, cellulose degradation

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 632-638

 

Indirect spectrophotometric determination of some biologically important phenothiazines using potassium dichromate, iron(II) and 1,10-phenanthroline

K Basavaiah

 

A sensitive method is presented for the spectrophotometric determination of phenothiazine derivatives of biological importance. The drugs namely, chlorpromazine hydrochloride (CPH), promethazine hydrochloride (PH), trifluoperazine hydrochloride (TFPH), prochlorperazine maleate (PCPM) and fluphenazine hydrochloride (FPH) are reacted with a fixed amount of dichromate in acidic conditions. After the reaction is complete, the unreacted dichromate is determined by treating with iron(II) and ortho-phenanthroline at a raised pH and measuring the absorbance at 510 nm. The amount of dichromate reacted corresponds to the drug content. The linearity ranges are found to be 5-30, 2.5-25, 5-45, 7.5-60 and 5-50 mg mL-1 for CPH, PH, TFPH, PCPM and FPH, respectively. The apparent molar absorptivity values are in the range 3.46´103-6.47´103 L mol-1 cm-1 and the limits of determination range from 0.49 to 1.87 mg mL-1 and the relative standard deviation is less than 2%. The proposed method has been applied for the determination of these drugs in pure form and in pharmaceutical formulations with recoveries in the range 96.28-103.24%. The method was further validated by parallel determination by the official British Pharmacopoeial procedure and by recovery studies.

 

IPC Code: C07 D 279/00, G01 J 3/00

Keywords: Iron(II), orthophenanthroline, phenothiazine determination, potassium dichromate

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 639-642

 

Application of aliovalency effect in the processing of refractory minerals

Ashok N Gokarn, Swati S Kulkarni* & Anita R  Pande

 

Doping of the matrix of mineral or chemical compound of different elements, with a small amount of salt is known to bring about the aliovalency effect. In essence, it is supposed to introduce defect or propagate its effect in the host element or matrix. This property has been judiciously exploited in the processing of refractory minerals like ilmenite, barite and celestite. Finally, the reasons for the success or failure of this effect in certain cases have been clearly elucidated.

 

IPC Code: C04 B

Keywords: Refractory mineral, aliovalency effect, ilmenite, barite

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 643-647

 

Transport of uranyl ion (UO22+) across bulk liquid membrane by thenoyl trifluoro acetone (TTA)

D Nanda, H P S Chauhan & B Maiti*

 

Transport of uranyl ion across a bulk chloroform membrane containing thenoyl trifluoro acetone (TTA) as carrier has been studied. The pH of the feed solution was maintained at 4 to 5 while 0.1M nitric acid served as stripping agent in the receiving compartment of the permeation cell. Various factors affecting the transport process have been studied and the optimum experimental conditions have been established. The optimum pH was adjusted to 5-5.5 while 0.1M HCl served as receiving solution. Presence of EDTA as masking agent in the feed solution eliminated the interference from Th(IV) and transition metal ions. The membrane system has been applied to the recovery of uranium from synthetic seawater. A forty-fold preconcentration of uranium with 96.46 recovery of the metal ion in a single stage operation could be accomplished.

 

IPC Code: B01 D 61/38, C22 B 60/02

Keywords: Bulk liquid membrane, transport of metal ions, TTA, preconcentration of uranium, thenoyl trifluoro acetone

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 648-653

 

Total gas analysis of nuclear fuels

Y Sesha Sayi*, C S Yadav, P S Shankaran & G C Chhapru

 

Total/occluded or residual gas content of sintered nuclear fuel pellets is an important specification. The specification of the gas content depends on the nature of the fuel and type of the reactor. The total gas content and its composition were determined employing hot vacuum extraction followed by quadrupole mass spectromety. Detailed investigations carried out on the determination of total gas in various types of nuclear fuels used in different types of reactors are reported in this paper. Oxide pellet is heated at 1650°C for 15 min while carbide pellet is heated at 1000°C for 30 min for the determination of total gas content. The overall measurement error is ± 5% and the detection limit is 0.005 cc. The main constituent of the gas is hydrogen (> 95%) in all the types of fuel pellets.

 

IPC Code: G21 C

Keywords: Occluded gas, residual gas, nuclear fuels, quadrupole mass spectrometry

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 654-658

 

Some physical and chemical properties of ostrich skins and leathers

 Behzat Oral Bitlisli*, Bahri Başaran, Özcan Sari, Ahmet Aslan & Gökhan Zengin

 

Some technological parameters of ostrich skins and leathers, which are considered to be important in the leather industry, were analysed. It was observed that these parameters vary according to whether skin comes from the neck, leg and back sides. However, on the basis of area and strength values, leg and back sides are more appropriate for upper leather production and neck sides may be used as accessories.

 

IPC Code: G01 N 33/44

Keywords: Ostrich skin, tanning, upper leather

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 659-671

 

Enzyme technology applications in leather processing

R B Choudhary, A K Jana & M K Jha*

 

The emphasis on the use of enzymes has come about because of the unique properties of the enzymes. The most important properties are the catalysis of chemical reactions at high rate under mild environmental conditions of pH, temperature and pressure, specificity of reactions, minimal side reactions, simple operations, non toxic nature and non polluting effluent generations. The leather industry world over is coming under pressure from environmental regulations to comply with the pollution and discharge legislation. The current activity in the area of leather processing is shifting towards the design and utilization of cleaner and softer technology like enzymatically enhanced processes. The enzymes are successfully employed for the better quality leather production with less pollution impact and also for the treatment of waste discharged from the industry. The leather processing from the raw skins to the finished products required the various steps like curing, soaking, liming, dehairing, bating, pickling, degreasing and tanning. The various processing principles have been discussed in brief along with application of suitable enzymes, their properties and sources. It showed that leather industries have enormous potential for the wide range of applications of several industrial enzymes.

 

IPC Code: C14 B 1/00

Keywords: Leather processing, enzyme technology

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 672-677

 

Evaluation of corrosion inhibition by cerium on aluminium
under marine and laboratory environments

Muhamed Ashraf P* & Leela Edwin

 

Cerium is considered to be a promising ecological alternative to toxic chromates in the field of corrosion protection. Studies were conducted to evaluate the corrosion inhibition by cerium on aluminium under marine and laboratory environments. The results revealed that under marine environment 1000 ppm Ce treated pure aluminium showed good corrosion inhibition than the Al-Mg alloy M57S. The corrosion rate was significantly high during post monsoon and summer season and cerium treated on pure aluminium showed superior corrosion inhibition in all the seasons. Cerium treated pure aluminium showed better corrosion inhibition as compared to untreated marine grade M57S aluminium. The laboratory evaluation of 1000 ppm cerium treatment on aluminium and its exposure in solutions of different salinity (5 to 200 ppt) revealed 30-66 and 0-92.6% efficient corrosion inhibition in pure and M57S aluminium respectively.

 

IPC Code: C23 F 11/00

Keywords: Cerium, corrosion inhibition, marine corrosion, aluminium corrosion

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 678-682

 

Ethylation of benzene over AFI type molecular sieves

 K Joseph Antony Raj & V R Vijayaraghavan*

 

Large pore aluminophosphate-based molecular sieves, MgMnAPO-5 and MnZnAPO-5, were synthesized by hydrothermal methods. The samples were characterised by the techniques of XRD, FT-IR, 31P and 27Al MAS-NMR spectra, BET-surface area, n-butylamine-TPD and ICP-MS chemical analysis. The catalytic performance of these materials has been examined for ethylation of benzene with ethanol in the vapour phase. The products were ethylbenzene, p-diethylbenzene, m-diethylbenzene, o-diethylbenzene and PAB[(1,2,4 and 1,3,5-triethylbenzene) and (1,2,4,5-tetraethylbenzene)]. Maximum conversion (20.6%) was observed at 400oC over MnZnAPO-5.

 

IPC Code: C07 C 15/04, C01 B 39/54

Keywords: Ethylation, ethylbenzene, benzene, molecular sieves

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 683-687

 

Zeolite supported iron catalyst for nitric oxide reduction
by ammonia in the presence of oxygen

 A V Salker

 

Iron based H-ZSM-5 catalysts were used to study NO reduction with NH3 in the presence of oxygen with and without humid conditions. The iron based H-ZSM-5 was prepared by wet impregnation method and characterized by X-ray diffraction technique, BET surface area and SEM. TPD experiments showed low and high temperature NH3 desorption peaks. FTIR indicated only ammonia adsorbed species. Fe/ZSM-5 showed better NOx reduction with NH3 than H-ZSM-5 which was a poor catalyst for the NOx reduction. The catalytic activity did not show significant difference in the NOx conversion with and without water, but there was significant difference in NH3 conversion. It may be said that the dispersed Fe species and acid sites were the active centers for the reduction of NO with NH3 in the presence of oxygen.

 

IPC Code: C01 B 21/24, BOI J 29/064

Keywords: NOx reduction, ammonia, Fe/ZSM-5, H-ZSM-5, Zeolite, iron catalyst

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 688-694

 

Synthesis of glycylcalix[6]arene and its applicability as resin for separation and preconcentration of trace transition metals

H Bhatt & Y K Agrawal*

 

A new glycylcalix[6]arene is synthesized by the reaction of glycine ethyl ester hydrochloride with acid chloride of p-carboxycalix[6]arene. Its physical properties, void volume, density, swelling, cation exchange capacity and t1/2 have been determined. The glycylcalix[6]arene is used as resin and its metal ion exchange capacities are determined. Mn(II), Fe(II), Co(II), Cu(II), Ni(II) and Zn(II) were absorbed at 5.5, 4.5, 6.0, 4.0, 4.8 and 5.0 pH, respectively. These were eluted with NaF, H2SO4, acetic acid, tartrate and HCl. The chromatographic separation of Mn(II), Fe(II) Co(II), Ni(II), Cu(II) and Zn(II) from each other was studied. These metals were preconcentrated on resin and determined in blood plasma and in the environment samples.

 

IPC Code: G01 N 33/44

Keywords: Glycylcalixarene, resin, trace transition metal, preconcentration

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 695-703

 

Studies of metal ion uptake behaviour of formaldehyde condensed resins of phenolic Schiff bases derived from the reaction of 4,4¢-diaminodiphenyl and
4, 4¢-diaminodiphenylmethane with o-hydroxybenzaldehyde

R K Dey*, S Acharya, S Samal & A R Ray

 

The metal ion uptake characteristics of two new chelating resins, o-HB-DDM-HCHO and o-HB-DD-HCHO, were examined towards transition metal ions like Cu2+, Ni2+ and UO22+ under both competitive and non-competitive conditions. The resin o-HB-DDM-HCHO was found to be more effective in removing metal ions in comparison to resin o-HB-DD-HCHO. Preferential adsorption of Cu2+ by both the resins was observed from the mixture of salt solution. Elution of the sorbed metal ions using dilute HCl resulted in removal of nearly 30-40% of the loaded Cu2+ and 34-45% of loaded UO22+ from the resin column.

 

IPC Code: C08 G 8/10, G01 N 33/44

Keywords: Metal ion, formaldehyde, resin, Schiff bases, adsorption

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 704-709

 

Determination of micropore volume and surface area of zeolite molecular sieves
by D-R and D-A equations: A comparative study

 Raj K Vyas, Shashi & Surendra Kumar*

 

Dubinin-Astakhov (D-A) equation is used for determining the micropore volume and surface area of zeolite molecular sieves (ZMS) by using physisorption measurements. Likewise, Dubinin–Radushkevich (D-R) equation is used for the estimation of these parameters for carbon molecular sieves (CMS), and, unlike D-A equation it does not require the estimation of the exponent n. In this paper, surface area and micropore volume of 13X molecular sieves (MS) have been determined by using both D-A and D-R equations. The results by both equations are in very good agreement. Therefore, D-R equation may also be used for estimation of these parameters because its application is simple and easier.

 

IPC Code: B01 J 29/04

Keywords: D-A equation, D-R equation, 13X molecular sieves, micropore volume, zeolite molecular sieves, physisorption measurements

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 710-713

 

Molecular interactions in binary liquid mixures of dimethylsulphoxide
with chloroethanes and chloroethenes

M Radhamma, K Sivakumar & M V P Rao*

 

Excess volumes (VE) were measured over the entire mole fraction range for mixtures of dimethylsulphoxide with 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloro-ethane, trichloroethene and tetrachloroethene at 303.15 K. The values of VE are negative for the system dimethylsulphoxide +1,1,1-trichloroethane and positive for the systems dimethylsulphoxide + 1,2-dichloroethane, +1,1,2,2-tetrachloroethane, +trichloroethene, and tetrachloroethene. The experimental data have been interpreted on the basis of molecular interactions between unlike molecules.

 

PC Code: G01 F

Keywords: Molecular interactions, binary liquid mixure, dimethylsulphoxide chloroethanes

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 714-718

 

Evaluation of apparent and partial molar volume of potassium ferro- and ferricyanides in aqueous alcohol solutions at different temperatures

U N Dash, G S Roy* & S Mohanty

 

Apparent and partial molar volume of potassium ferro- and ferricyanides in aqueous alcohol solutions have been determined at four different temperatures 298.15, 303.15, 308.15 and 313.15K with the objective of studying ion-solvent interaction in these systems. The transfer of volumes for the transfer of these salts from aqueous alcohol solution to water has been evaluated. Negative transfer of volume was observed and the results have been explained on the basis of electrostriction.

 

IPC Code: G01 N 9/00, C01 C 3/12

Keywords:   Apparent molar volume, partial molar volume, potassium ferrocyanide, apparent molar expansibility, aqueous  alcohol

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 719-725

 

A generalized correlation of nucleate pool boiling of liquids

S  Bhaumik, V K  Agarwal &  S C  Gupta*

 

An experimental study on nucleate pool boiling of distilled water, benzene and toluene from a horizontally laid plain stainless steel heating tube at atmospheric and subatmospheric pressure has been discussed here. The main objective of the investigation is to study the variation of heat transfer coefficient around the circumference of heating tube and thereby to determine functional relationship of local and average heat transfer coefficient with heat flux and pressure. Further, a generalized correlation of boiling heat transfer coefficient of various liquids has been developed to examine the consistency of experimental data conducted on heating surfaces of different characteristics.

 

Keywords:   Nucleate boiling, surface-liquid combination factor, heat transfer coefficient

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September 2004, pp. 726-731

 

Chromatography of heavy metal cations with formic acid containing mobile phases: Effect of added organic solvents and surfactants on the mobility of cations

Ali Mohammad* & Yasir Hamid Sirwal

 

Chromatography of fifteen metal ions has been performed on silica gel high-performance thin-layer chromatographic plates with mobile phase systems containing formic acid. The effect of protic and aprotic organic modifiers (methanol, ethanol, acetone, acetonitrile, DMSO, and dioxane) and surfactants (SDS, CTAB or Triton X-100) concentrations below and above the critical micellar concentration (CMC) on the retention behaviour of the metal cations was examined. A novel mobile phase system comprising of 1.0 M HCOOH and 1.0 M HCOONa in volume ratio of 7:3 was identified as the best mobile phase for rapid separation and identification of mixtures of Ni2+, Cd2+ and Ag+. The lower limit of detection for Cu2+, Ni2+, Co2+ and Pb2+ on HPTLC was determined and semiquantitative determination of Ni2+, Pb2+, Tl+ and Fe3+ by spot-area measurement was attempted. The proposed method was successfully applied for identification and separation of nickel, cadmium, and silver from river and industrial wastewater as well as from hydroxide sludge samples.

 

IPC Code: B01 D 15/08

Keywords: Formic acid, surfactants, chromatography, heavy metal cations

 

 

 

Indian Journal of Chemical Technology

 Vol. 11, September, 2004, pp. 732-743

 

Phlogiston: The rise and fall of a theory

Jaime Wisniak

 

The phlogiston theory was born around 1700 and lasted for about one hundred years. It provided for the first time a unifying approach to widely different chemical and physical phenomena and as such was adopted by the most famous European scientists, particularly the French ones. Its demise came with Lavoisier’s new insights into the phenomena of chemical reactions in general and combustion in particular, as well as about the composition of air. Lavoisier’s results disproved the phlogiston theory and established the applicability of the principle of mass conservation to chemical reactions.

 

Keywords: Phlogiston, Lavoisier theory, mass conservation