JCSN Vol 39 No 2 2014

POLYCYCLIC AROMATIC HYDROCARBONS IN NIGERIAN COAL EXTRACTS

*1K.E. Ugwu and 2P.O. Ukoha

1National Center for Energy Research and Development, University of Nigeria, Nsukka.

2Department of Pure and Industrial Chemistry, University of Nigeria, Nsukka.

*Corresponding author: kenecis@yahoo.co.uk

Abstract

Nine coal samples, consisting of bituminous and sub-bituminous coals, obtained from mines located in Ribadu and in Okobo (Nigeria) respectively were studied for the concentrations of some polycyclic aromatic hydrocarbons (PAHs) in the coals. The samples were extracted separately with acetone, dichloromethane (DCM) and n-hexane in a soxhlet extractor. These solvents have relatively low boiling points and readily available. The extraction ability of these solvents was evaluated on the basis of the amount of PAHs extracted from the samples. The PAHs in the extracts were determined using gas chromatography coupled with flame ionization detector (GC-FID). The results showed acetone extracted 535.31ppb of the target PAHs from the sub-bituminous coal and 961.89ppb of the target PAHs from the bituminous coal.  DCM extracted a total of 757.71ppb of the target PAHs in the sub-bituminous coal and 1243.03ppb of the target PAHs from the bituminous coal while n-hexane extracted 1690.95 ppb of the target PAHs from the sub-bituminous coal and 867.20ppb of the target PAHs from the bituminous coal. The solvents’ ability to extract different PAHs  in decreasing order was DCM>acetone>n-hexane. The quantity of PAHs extracted in decreasing order was DCM>acetone>n-hexane for bituminous coal, and n-hexane>DCM>acetone for the sub-bituminous coal. The extraction of any PAH varied on solvent basis and on the coal type. The solvents extracted more three-ring PAHs than other PAHs.

 

STUDIES ON THE EFFECTS OF pH AND CONCENTRATION ON HEAVY METALS (Cd2+ AND Hg2+) ADSORPTION USING BOILER FLY ASH

1N. E. Okoronkwo, 1*J. C. Igwe, 2A. A. Abia and 1I. S. Eze

1Department of Industrial Chemistry, Faculty of Biological and Physical Sciences, Abia State University, P.M.B. 2000 Uturu, Nigeria.

2Department of Pure and Industrial Chemistry, Faculty of Sciences, University of Port Harcourt, River State,

Nigeria.

*Corresponding author: jcigwe2001@yahoo.com

Abstract

The effect of pH and concentration on heavy metals (Hg2+ and Cd2+) adsorption using unmodified boiler fly ash was investigated. The results showed that pH characteristically affected the adsorption process. The maximum amount adsorbed occurred at about pH of 6. The pH at zero point of charge (pHzpc) was used to ascertain the adsorption properties of the boiler fly ash. The amount adsorbed increased as initial concentration of metal ions increased and Hg2+ was adsorbed higher than Cd2+ ion. The effect of concentration on the sorption process was modeled using Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Frumkin and Harkins-Jura isotherms. The Freundlich isotherm gave a better fit to the sorption process and the values of the Freundlich exponent showed favorable adsorption. From the D-R equation, the mean free energy of adsorption was found to be 50 kJmol-1 indicating chemisorptions mechanisms. From the Frumkin isotherm, the change in free energy of adsorption (∆G) was found to be 15.31 and 15.38 kJmol-1 for Cd2+ and Hg2+ ions respectively. A two way analysis of variance (ANOVA) without replication was used to ascertain the significance in the fitness of the different isotherms in the modeling of the sorption process and the result showed no significant difference between the six isotherms in describing the adsorption of the divalent metal ions onto waste boiler fly ash.

 

HUMAN CARCINOGENIC RISK ASSESSMENT OF POLYCYCLIC AROMATIC HYDROCARBONS IN FRESHWATER SAMPLES FROM OGBA/EGBEMA/NDONI COMMUNITIES IN RIVERS STATE, NIGERIA

1*E. Inam, 1E. Owhoeke and 2J. Essien

1Environmental and Radioanalytical Research Group, Department of Chemistry, University of Uyo, Akwa Ibom State, Nigeria

2Department of Microbiology, University of Uyo, Akwa Ibom State, Nigeria

*Corresponding author: eduinam235@gmail.com

Abstract

Freshwater samples from oil producing communities of Egi, Omoku and Egbema in Ogba/Egbema/Ndoni Local Government Area of Rivers State, Nigeria were examined for polycyclic aromatic hydrocarbons (PAHs) loads and the human carcinogenic risk of sixteen United State Environmental Protection Agency (US EPA) priority PAH suites. Determination of PAHs was done using gas chromatography/flame ionization detector (GC/FID) and the results show that the concentrations of PAHs in the water samples ranged from 1.38μg/L to 5.96μg/L with mean value of 3.33±0.18μg/L. The average total PAHs recorded for the three communities were Egi (3.39±0.17μg/L), Omoku (1.90±0.13μg/L) and Egbema (4.71±0.23μg/L) for Egi, Omoku and Egbema respectively. The dominant PAHs suites were benzo (b) fluoranthene, indeno (1, 2, 3-cd) pyrene, phenanthrene and benzo (k) fluoranthene. The cancer risk due to c-PAHs from ingestion of water was estimated using the standards given by the US EPA for 10years, 25years and 70years old and the results were 4.88E-5, 6.09E-5 and 6.87E-5 respectively. These values are within the range of the US EPA risk management criterion (10-6 to 10-4) where management decision should be considered. There is therefore need for mitigation actions to protect public health.

 

PROXIMATE AND PHYTOCHEMICAL ANALYSES OF PUMPKIN (CUCURBITA MAXIMA) PEE

*R. F. Olayemi and H. E. Salihu

Department of Applied Science, College of Science & Technology, Kaduna Polytechnic

P.M.B.2021 Kaduna, Nigeria.

*Corresponding author: rianatfo@gmail.com

Abstract

Pumpkin(Cucurbita maxima) peel was analyzed for its proximate composition and  phytochemical constituents. Various standard techniques were used in the phytochemical and  proximate analyses. The phytochemical screening revealed the presence of tannins, saponins, phlobatannins, flavonoids, terpenoids, steroids, alkaloids, carbohydrates and glycosides. The sample was found to contain all the phytochemicals tested in varying degrees except anthraquinones that was not detected. Results of proximate analysis revealed that moisture, ash, fat, crude fibre, crude protein and carbohydrate contents were 5.20, 6.32, 3.11, 35.97, 11.73, and 37.67% respectively. The presence of bioactive compounds and the result of proximate analysis is an indication that pumpkin peel has medicinal activity, and could also be used as food. Therefore the peel could serve as a source of ingredient to the food and pharmaceutical industries.

 

THERMODYNAMICS OF RESIDUAL OIL ADSORPTION FROM PALM OIL MILL EFFLUENT (POME) USING BOILER FLY ASH

1*J. C. Igwe, 2U. Arukwe, 3A. A. Abia and 4C. U. Sonde.

1Department of Industrial Chemistry; 2Department of Biochemistry; Abia State University P.M.B 2000 Uturu, Abia State Nigeria.

3Department of Pure and Industrial Chemistry University of Port Harcourt, River State Nigeria.

4Department of Chemistry, Michael Okpara Federal University of Agriculture Umudike Abia State, Nigeria.

*Corresponding author: jcigwe2001@yahoo.com

Abstract

The effect of temperature on the removal of residual oil from palm oil mill effluent (POME) using boiler fly ash was investigated by measuring the residual oil concentration using UV spectrophotometer at wavelength of 444 nm. The POME was pre-treated with alum and the residual oil extracted with petroleum ether prior to adsorption studies. The amount of residual oil adsorbed decreased as temperature was increased. Maximum percentage adsorbed was 94.46% at 273 K while the minimum was 76.80% at 343 K. The thermodynamic parameters DGo, DHo, DSo and EA were evaluated. All values of DGo were negative ranging from -7.12 to -3.45 kJ/mol at temperatures of 273 to 343 K. All values of DHo, DSo and EA were also negative. The thermodynamic equilibrium constant Kc were all >1 and decreased as temperature was increased. The adsorption of residual oil from POME using boiler fly ash was found to be spontaneous, feasible and exothermic. There was a decreased randomness at the solid/solution interface during the sorption process. Also, the sticking probability relationship showed that as temperature was increased, there was an increase in the tendency of residual oil unsticking to the adsorbent surface. Therefore, boiler fly ash, a waste from the palm oil mill, was effectively used to remove residual oil from POME and it was shown that the sorption process was highly temperature dependent. Hence, as a result of the importance of temperature effect on adsorption processes, this serves as one step in the design of a treatment plant for residual oil from POME and this will help in achieving the much needed zero discharge from palm oil mills.

 

TIME SERIES MODEL FOR GLUCOSE CONVERSION TO ETHANOL IN RELATION TO ETHANOL LOSS DURING FERMENTATION

E. Duru

Department of Chemistry, Alvan Ikoku Federal College of Education, P.M.B. 1033, Owerri Imo State, Nigeria.

Correspondence author: chidiedbertduru@gmail.com

Abstract

The conversion of glucose to ethanol during fermentation using Saccharomyces cerevisiae and the spontaneous removal of this product at a point in the process was simulated and interpreted using a time series model. The peak concentration of ethanol in the solution before the commencement of its removal was 11.1 % v/v reached in 96 hours at a reaction solution pH of 3.95 and proceeded at a rate of 1.18 × 10-2 ml/hr. The removal of ethanol from the reaction system after 96 hours was attributed to the oxidative conversion of this molecule to acetic acid which manifested by a rapid drop in the pH of the solution. The rate of this oxidation reaction was found to be 2.29 × 10-2 ml/hr which is about two times faster than the rate of ethanol formation at the commencement of the fermentation process. The accumulation of acetic acid which resulted in the increased acidity of the reaction solution could have been responsible for the decrease in yeast activity or possible toxicity as has been reported.

 

STUDY OF THE EFFECT OF pH AND SUPPORTING ELECTROLYTES ON PERMEATION OF IONS, THROUGH A POLYMERIC MEMBRANE

*1B. N Okolue and 2C. I. Ekeocha  and 3B. I. Ikeaka

 1Federal University of Technology,  P.M.B, 1526, Owerri, Imo State. Nigeria.

 2National Mathematical Centre, Sheda – Kwali, P.M.B 118 Garki, Abuja [FCT], Nigeria.

 3Oil Test Group, 312 Danjuma Drive, Trans Amadi Industrial Layout Port-Harcourt, Rivers State. Nigeria.

Corresponding author: okolueben@yahoo.com,

Abstract

 Despite intense studies over years, the mechanism behind the movement of water and other small nanoelectrolyte through membranes remains unclear. Previous Researchers had focused on some factors affecting this movement like nature of membrane, permeation time, concentration of electrolyte samples, ionic size, etc. It is on this basis that we conducted a research on the effect of pH and supporting electrolytes on permeation of ions through a polymeric membrane using conductometric technique at 25 .The results obtained from the study shows that diffusion rate of various electrolyte samples increases gradually with increase in time. Also on addition of supporting electrolyte, there was a rapid increment in the diffusion rate. This was as a result of increment in the concentration of the counter ions (cations) which were attracted to the membrane matrix while the chloride ions are excluded from the membrane phase. However, there was a drop in the rate of permeation of ions at pH of 4 which could be attributed to the interference of the hydrogen ion [H+] with the electrolyte solution and thus retarding the rate of permeation. Nevertheless, a slight increment was observed in an alkaline medium on pH 11. The diffusion trend can be said to follow the pattern of Al3+<Ca2+<Na+. The permeation flux calculated using the derived Fick’s law shows good agreement with the experimental values. Thus these factors and others should be considered in the use of membranes for scientific work like in ultra filtration, water purification, reverse osmosis, nanofiltration, microfiltration etc.

 

ADSORPTION STUDIES OF CHLORPYRIFOS AND ENDOSULFAN PESTICIDES FROM AQUEOUS SOLUTION USING COCONUT FIBRE

*J. C. Igwe, N. E. Okoronkwo and E. A. Okoli

Department of Pure and Industrial Chemistry Abia State University Uturu, P.M.B. 2000 Uturu Abia State

*Corresponding author: jcigwe2001@yahoo.com

Abstract

The adsorption removal of Chlorpyrifos and Endosulfan pesticides from aqueous solution using activated and unactivated coconut fibre was investigated in this study. The coconut fibre was cut into pieces, powdered in a grinder and was activated with 2% nitric acid for 24 hrs. Sorption experiments were performed at concentration range of 10-100 mg/L and contact time of 10-120 mins. The pesticide concentrations were monitored using UV-Visible absorption spectrophotometer. The amount of pesticides adsorbed increased as the contact time and initial concentration was increased. Adsorption equilibrium was reached at about 60 mins contact time. Activation of the adsorbent enhanced the sorption capacity of the adsorbent. The sorption of both pesticides was better for the activated coconut fiber than the unactivated fiber with chlorpyrifos showing higher sorption capacities. Pseudo-second order equation gave a better fit to the kinetic experimental data with rate constant (K2) values ranging from 1.94 x10-3 to 3.66 x 10-3 (g.mg-1.min-1) and the sorption process was found to be particle diffusion controlled. The equilibrium data was modeled using four isotherm equations namely Langmuir, Freundlich, Dubin-Radushkevich and Temkin isotherms. The maximum sorption capacity qmax (mg/g) gave 78.740 and 59.880 for chlorpyrifos and 37.313 and 62.893 for Endosulfan on activated and unactivated coconut fiber respectively. Freundlich isotherm gave a better fit to the equilibrium experimental data with linear correlation coefficient (R2) values ranging from 0.8524 to 0.9950. The sorption process was found to follow chemisorption mechanism as was seen from the mean sorption energy values of 288.68 to 1118.03 KJ/mol. Therefore activated and unactivated coconut fibre was used as an effective adsorbent for Chlorpyrifos and Endosulfan adsorption from aqueous solution

 

EFFECTS OF COMBUSTION TEMPERATURE AND TIME ON THE PHYSICAL PROPERTIES OF RICE HUSK ASH

D. Igwebike-Ossi

Department of Industrial Chemistry, Ebonyi State University, Abakaliki, Nigeria

Corresponding author: clemdossi@yahoo.com

Abstract

This study investigated the effects of different combustion temperatures and duration on the physical properties of the ash produced from rice husks at known heating rates. Milled rice husks of particle size in the range of 300 to 1000µm were subjected to controlled incineration in a muffle furnace at varied temperatures of 400-10000C and duration of 1-6hrs. The colours of the rice husk ash (RHA) samples obtained at the various combustion conditions were qualitatively and quantitatively characterized using a colour scale in which black and brilliant white were assigned the values 10 and 1, respectively. The results showed a general lightening of colour with increase in combustion time but to a limit. A preponderance of black and dark brown ash samples was obtained at 4000C from 1 to 3hrs but with longer combustion time of 4-6hrs, the ash became light brown. At 5000C, ‘white’ ash was obtained from the 3rd hour beyond which there was no improvement in the ‘whiteness’ of the ash formed. At 600 – 8000C, ‘white’ ash was formed from the first hour, but the ‘whiteness’ of the ash samples became brighter with increased combustion time. At high combustion temperatures of 900 and 10000C grey ash was produced  from the first hour to the sixth hour at high heating rates, of 32 and 270C/ min respectively but at low heating rates (15.32 and 9.80C/min), ‘white’ ash was formed at all the combustion hours. The colour numbers generally decreased with increasing combustion temperature and time. An evaluation of the texture of the ash samples, showed that RHA samples produced at 400-700oC, were ‘soft’ indicating the presence of amorphous silica while those produced at 800-1000oC were ‘hard’ showing a predominance of crystalline silica.

 

EVALUATION OF INDOOR AIR POLLUTANTS IN SELECTED HOSTELS OF SOME TERTIARY INSTITUTIONS IN OWERRI – NIGERIA

*1, 2C. E. Ogukwe,  1C. F Nnadozie and  1, 2D. I. Njoku

1Department of Chemistry Federal University of Technology Owerri

2Electrochemistry and Material Science Research Unit, Federal University of Technology Owerri.

*Corresponding author: cynthiaogukwe94@yahoo.com

Abstract      

The indoor air quality in some hostels located in the two most populated higher institutions in Owerri municipal have been investigated by evaluating the levels of some constituting air pollutants in the study area. NO2, H2S, CH4, SO2 andNH3as air quality parameters  were measured with in-situ gas monitors; while temperature, relative humidity, wind speed and irradiance which are referred to as the meteorological parameters were determined with multi-digital environmental meter. Data obtained from dry season samples were compared with those obtained from rainy season samples and USEPA, WHO and FEPA standards were used as point of reference. The result indicated that the average monthly level of the pollutants were below the permissible limit for these standards, except H2S that exceeded the FEPA (0.008) limit within the period under study. The season of the months and the activities of the students affected the level of the average monthly concentration of the pollutants.The correlation analysis of the data showed that the studied meteorological parameters jointly influenced (5-32%) the levels of the pollutants in the two locations studied.

 

CHARACTERISTICS OF LAGENARIA SICERARIA SEED OIL

*N. Surma, E. N. Iornumbe  and   J.T. Akaahan

Department of Chemistry, University of Agriculture P.M.B 2373, Makurdi

Corresponding author: nguamo.surma@yahoo.com

Abstract

Vegetable oil was extracted from seeds of species of melon (Lagenariaiceraria) using n-hexane as the solvent. After stripping off the solvent by rotatory evaporation, the oil was dried at 55oC in the oven and characterized. Results showed: Percentage yield (% by wt, 52.940); Moisture content (% by vol, 2.500); crude fiber (% by wt, 1.333); Total ash (% by wt, 0.500); Crude fat (% by wt, 36.500). Physiochemical determinations of the oil from Lagenaria siceraria seed gave the following result: Specific gravity (g/cm3,0.990); Viscosity (centipoise,19.540); Saponification value (mg/g, 172.522); Acid value (mgKOH/g, 3.666); Peroxide value (mg/g, 9.980). The vegetable oil extracted from lagenaria Siceraria seed was yellowish in color. The relatively high saponification value and low acid value of the oil suggest that it could be used in the manufacture of soap and also in the production of biodiesel.

 

PHYSICO-CHEMICAL PROPERTIES OF RIVER MADA, NASARAWA STATE, NIGERIA

*I. S. Eneji, A. Y. Ahmed and P. O. Onuwa

Department of Chemistry and Centre for Agrochemical Technology, University of Agriculture, Makurdi,Benue State, Nigeria.

*Corresponding Author: ishaqeneji@gmail.com

Abstract

The physicochemical parameters of River Mada in Nasarawa State were investigated for two seasons (rainy and dry seasons). The level of heavy metals (Cr, Cd and Pd) contamination in this river was also studied using Atomic Absorption Spectrophotometric technique. The results of the analysis show the concentration of heavy metals in ppm, (Cr) (0.325 ± 0.49), (Cd) (0.0196 ± 1.00) and (Pb) (0.483 ± 0.12). The results were also compared with the World Health Organization (WHO) standard for drinking water. The pH was determined to be 6.83 ± 0.80 during rainy season which was slightly acidic and 7.70 ± 0.12 during dry season which was slightly alkaline. The relatively high level of heavy metals indicates slight degree of contamination. More of the other parameters determined were below or within the range of WHO standard for drinking water except turbidity.

 

SORPTION ISOTHERM STUDIES OF Cd2+ AND Pb2+ FROM AQUEOUS SOLUTIONS USING EDTA-MODIFIED BOILER FLY ASH

E. Okoronkwo, *J. C. Igwe and U. E. Obasi

Department of Pure and Industrial Chemistry, Faculty of Biological and Physical Sciences, Abia State University, P.M.B. 2000 Uturu, Abia State Nigeria.

*Corresponding author: jcigwe2001@yahoo.com

Abstract

The removal of Cd(II) and Pb(II) from aqueous solutions using EDTA-modified boiler fly ash was investigated in this paper in a batch system by monitoring the concentration of the metal ions using atomic absorption spectrophotometer.  The results showed that EDTA-modified boiler fly ash was capable of removing Cd(II) and Pb(II) ions from solution.  The percentage adsorbed increased as initial concentration was increased and Pb(II) ion was adsorbed more than Cd(II) ion.  The sorption experimental data was modeled using six isotherm models namely, Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Harkins-Jura (H-J) and Flurry-Huggins (F-H) isotherms. The D-R isotherm gave the best fit and the sorption process was found to follow chemisorption mechanism.  The differences in the fitness of the isotherm were found not to be significant through a two way ANOVA applied to the experimental data.  Therefore, EDTA-modified boiler fly ash was found to be a good adsorbent for Cd(II) and Pb(II) ions removal from aqueous solution.

 

QUALITATIVE IDENTIFICATION OF QUARTZ AND DICKITE IN THE SOIL OF MBOM UMUAHIA. ABIA, NIGERIA  BY X-RAY DIFFRACTION

1I. E. Otuokere   and  2U. E. Ekpunobi

. 1Department of Chemistry, Michael Okpara University of Agriculture, Umudike

.2Department of Pure and Industrial chemistry, Nnamdi Azikiwe University, Awka.

Corressponding author: tosmanbaba@yahoo.com

Abstract

Soil samples in Mbom Umuahia were characterized for their mineralogical potentials.  X-ray diffraction was used in the mineralogical characterization. Result obtained was analyzed using Bragg-Wolf equation and International centre for diffraction data software. Bragg’s equation was used to find the d-value corresponding to Bragg’s angles. The d-values which were obtained from samples were compared with standard values. The d-spacing 3.34454, 4.25943, 1.81793 Å in the x-ray diffraction pattern of sample A compared well with the d-spacing in the reference stick pattern for quartz  SiO2 3.34390, 4.25570, 1.81810 Å. Other d-spacing values of the diffractogram compare well with the reference stick pattern. The identification of quartz with Hexagonal Crystal system, space group P3221, lattice constant a (Å): 4.9141, b (Å): 4.9141, c (Å): 5.4060, α (°):90.0000 , β(°): 90.0000,   γ (°):120.0000, volume of cell (Å3):113.06 , Z: 3.00  and Referece Intensity Ratio: 3.32 was suggested. The following d-spacing  7.15761, 3.57137, 2.33950 Å in the x-ray diffraction pattern of sample A  compare well with the reference stick pattern for Dickite, Al2Si2O5( OH )4. Dickite with monoclinic crystal system,  Space group: Cc, lattice constant a(Å):5.1477; b (Å):8.9396; c (Å): 14.4164 , α (°):90.0000 , β (°): 96.7182 , γ (°):90.0000, measured density (g/cm3):2.58 and cell volume (Å3):658.86 and  Z:4.00 was also suggested. We therefore conclude that the sample is an admixture of quartz and dickite.

 

PHYSICO-MECHANICAL PROPERTIES OF VULCANIZATES FROM BLENDS OF EPOXIDIZED-DEPOLYMERIZED RUBBER AND MODIFIED AFRICAN STAR APPLE (CHRYSOPHYLLUM ALBIDUM) SEED SHELLS.

1D. Malomo, 2*A. K. Akinlabi, 3S. O. Babajide, 4K. O. Koleoso and 3O. M. Oyenekan

1Chemistry Department, Federal University, Oye, Ekiti State, Nigeria.

2Chemistry Department, Federal University of Agriculture, PMB 2240, Abeokuta.

3Science Laboratory Technology Dept., Moshood Abiola Polytechnic, Abeokuta.

4Pharmaceutical Technology Department, Moshood Abiola Polytechnic, Abeokuta.

*Corresponding author: akakinlabi@yahoo.com

Abstract

Epoxidized-Depolymerised Low Molecular Weight Natural Rubber (EDLNR) was mixed with natural rubber in the ratio 30:70. Carbon black (CB) and carbonized forms of inner and outer shells of African Star Apple (chrysophyllum albidum) seed were used in various ratios during the compounding of the rubber blends. The carbonized Africa Star Apple inner seed shell (CASAIS) and carbonized Africa Star Apple outer seed (CASAOS) shells were separately used in the compounding by gradually replacing carbon black with each of these new materials at various ratios of 0%, 5%, 10%, 15%, 20%, 25% and 50% of carbon black. For the set of CASAIS, there were seven mixes and for the set of CASAOS, there were also seven mixes, making fourteen mixes in all. Prior to compounding, analysis of the inner and outer seed shells viz-a-viz: particle size distribution, loss on ignition, iodine absorption, moisture contents, ash contents, pH and elemental compositions were first carried out. After compounding, the vulcanizates were subjected to rheological, physical and mechanical tests. On the basis of the investigated properties, it was observed that both carbonized inner and outer African Star Apple seed shells acted as softener/plasticizer in the rubber matrix. Strength and rheological properties of mixes with CASAOS were found to be slightly better than the CASAIS. Though, compatibility of CASAIS and CASAOS with the rubber blends was observed, but 10% blend of each with CB showed appreciable engineering values that can be recommended.

 

AGERATUM CONYZOIDES,  L. EXTRACT AS INHIBITOR FOR CORROSION OF SX 316 STEEL IN SULPHURIC ACID SOLUTION

*O. O Adeyemi, O. O Olubomehin and R. O. Bello

Chemical Sciences Department, Olabisi Onabanjo University, P.O. Box 364, AgoIwoye, Nigeria.

*Corresponding author: oo_adeyemi@yahoo.co.uk

Abstract

The inhibitive effect of the extract of Ageratum conyzoides on corrosion of SX 316 steel in H2SO4 solution was determined using weight loss measurement and galvanostatic polarisation techniques. It was found that the presence of the plant extract reduces markedly the corrosion of steel in acid solution. The inhibition efficiency increases as the plant extract concentration is increased. The inhibitive effect of A. conyzoides extract (ACE) was discussed on the basis of adsorption of the components on the metal surface. Negative value of energy of adsorption indicates the spontaneity of the process.

 

SYNTHESIS AND ANTIMICROBIAL STUDIES OF N, N1-BIS (4-IMETHYLAMINOBENZYLIDENE) ETHANE-1, 2-DIAMINE (DAED) AND ITS NICKEL (II) AND PLATINUM (IV) COMPLEXES.

O Ukoha and *U. S Oruma

Coordination Chemistry and Inorganic Pharmaceuticals Unit, Department of Pure and Industrial Chemistry, University of Nigeria, Nsukka, Nigeria.

Corresponding author: susan.oruma@unn.edu.ng

Abstract

N,N1-Bis(4-dimethylaminobenzylidene)ethane-1,2-diamine was synthesized by the condensation of ethane-1, 2-diamine with 4-dimethylaminobenzaldehyde in 1:2 mole ratio. The Ni (II) and Pt (IV) complexes of the ligand were also synthesized and characterized by UV/Visible, IR, 1H and 13C NMR spectral studies. Spectral data infers that N,N1-Bis (4-dimethylaminobenzylidene) ethane-1, 2-diamine coordinated to the metals as a tetradentate ligand. Both complexes show 1:1 stoichiometry. The ligand and complexes were screened for their in vitro antibacterial activity against Staphylococcus aureus, Escherichia coli and Proteus mirabilis clinical bacterial strains by the agar-well diffusion method. The Ni (II) complex showed highest activity against the micro-organisms while the ligand showed least activity at concentration of 20mg/ml.

 

AQUEOUS PHASE REDUCTIVE DETOXIFICATION OF Cr(VI)  BY SODIUM THIOSULPHATE: KINETICS, THERMODYNAMICS AND STOICHIOMETRY

1*M. S. Iorungwa,  1R. A.Wuana, 2S. G. Yiase and 1T. A. Tor-anyiin

1Institute of Inorganic Chemistry and Pollution Control, University of Agriculture, 970001, Makurdi-Nigeria

2Department of Chemistry, Benue State University, 970001, Makurdi – Nigeria

Corresponding author: saviour.moses@gmail.com

Abstract

The suitability of Na2S2O3 was assessed as an inorganic reductant of Cr(VI) in aqueous phase. The absorbance of Cr(VI) was monitored at 349 nm using a Milton  Roy Spectronic 20D UV/Visible spectrophotometer  at different temperatures (298 – 323 K) to study the effect of temperature on reduction while, the effect of pH was studied at pH 3, 5, 7, 9 and 12. The effect of concentration was also considered by varying the concentrations of Na2S2O3 (i.e. 4, 6, 8, 10 and 12 mg L-1) over a pH of 5 and 9 at 298 K and 5 minutes with concentration of Cr(VI) set at 10 mg L-1. The temperature effect showed that the reaction rate increased slightly with increase in temperature. It was found that there was a logarithmic increase in time required to reach a certain percentage reduction of the [Cr(VI)]initial, as the pH was increased. The kinetic results showed that the reaction was first – order with respect to Cr(VI) with the rate equation of . The activation entropy obtained from plots of ln(kobs/T) vs. 1/T was -197.53 J.K-1.mol-1 agreeing with the formation of a condensed compound. The activation enthalpy varied from (-8.31×10-5 – 1.66×10-4 kJmol-1) and most cases it was negative showing that the reaction was rather exothermic. The activation energies obtained were 58.87, 60.84, 62.82, 63.80 and   65.78 kJmol-1 for the respective Kelvin temperatures of 298, 308, 318,323 and 333. This increase in activation energy with increasing temperature implied that bond breakage and product formation was more favourable at lower temperature.  The stoichiometry therefore suggested was 1 Cr(VI) : 1.13 Na2S2O3, this value was found to be in agreement with the theoretically obtained result for both acidic and alkaline media.  This implies that the stoichiometry does not depend on pH. The findings from the research show that Na2S2O3 could be used for the reductive detoxification of Cr(VI) in polluted areas.

 

PHYSICO-CHEMICAL ASSESSMENT OF WATER AND PROCESSED MEAT FROM TWO VARIETIES OF COCONUT (COCOS NUCIFERA)

1F. I. Obahiagbon, 1E. C. Dania and 2*E. G. Ilori

1Science Laboratory Department, University of Benin, Benin City

2Central Analytical Laboratory, Nigerian Institute for Oil Palm Research, NIFOR, Benin City

*Corresponding author: esohe_grc@yahoo.com

Abstract

In this study, the physical (pH, conductivity, colour, taste and density) and nutritional composition (moisture content, sucrose, protein, ascorbic acid, ash, lipid, fibre, carbohydrate, phosphorus, calcium, magnesium, sodium, potassium, zinc, manganese, iron, copper, and thiamine) of two varieties of Cocos nucifera ‘Malayan Dwarf’ (green and yellow) water and processed coconut meat were assessed. Results obtained showed presence of nutrients in the water and processed meat of both varieties of coconut. Both coconut varieties (dwarf green and yellow) were found to have sweet taste and cloudy white colour with slightly acidic pH which varied significantly amongst the types of coconut (mean pH of 5.72 and 6.22 for the green and yellow coconut respectively). The statistical analysis conducted on the results revealed significant differences in the nutrients of the coconut waters and derived creamed product. Conclusively, the present assessment done on the coconut water and derived creamed product revealed that the nutrients required for daily healthy living are present in them.

 

PHYTOCHEMICAL AND ANTIBACTERIAL STUDIES ON  HYMENOCARDIA ACIDA ROOTS.

Y. Shimbe and *T. A. Tor-Anyiin

Department of Chemistry, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria.

*Corresponding author: toranyiint@yahoo.com

Abstract

Hymenocardia acida is one of the useful plants of traditional medicine in Nigeria. Phytochemical studies of  whole roots of the plant was carried out using standard procedures. After sequential extraction using hexane, ethyl acetate and methanol, these extracts were found to contain: carbohydrates, tannins, saponins, terpenes, sterols, flavonoids, glycosides and phenols. Antimicrobial activity screening of these extracts was carried out using, Salmonella typhi, Escherichia coli (Gram positive), Staphylococcus aureus and Klebsiella pneumonae (Gram negative) pathogens. In general, the extracts showed activity on the bacteria species with the exception of K.pneumonae. Minimum Inhibitory Concentration (MIC) results of the methanolic extract showed 20 mg/ml for S. aureus, 40 mg/ml for both E. coli and S. typhi. It can be concluded that the activity shown by the extracts of the plant is as a result of the phytochemicals present in them.

 

COPOLYMERIZATION OF METHYLOL UREA WITH WASTE POLYSTYRENE: OPTIMIZATION OF PROCESSING VISCOSITY

S.A. Osemeahon

Department of chemistry, ModibboAdama University of Technology, Yola, Nigeria.

Corresponding author: sundayosemeahon@yahoo.com

Abstract

The effect of methylol urea (MU) viscosity on the reactive blending of MU with waste polystyrene (PS) to give methylol urea/waste polystyrene (MU/PS) copolymer composite was investigated. Some physical properties of MU/PS attained at different viscosities (3.64-257mPa.s) were evaluated. Some of the properties namely melting point, refractive index and formaldehyde emission were found to increase with increase in MU viscosity while the solubility in water, moisture uptake, elongation at break and density were found to decrease with increase in viscosity. MU viscosity above 7.51mPa.s was found to be insoluble in water, suggesting that processing MU/PS copolymer should be carried out below a viscosity of 7.15mPas. The result from this study will guide formulators toward choice and control of formulation processes in the quest to develop new uses from MU/PS copolymer resin.

 

ISOLATION AND BIOACTIVITY OF 1,2,3-TRILINOLENYL TRIGLYCERIDE, 18:3 (6, 9, 12) FROM THE LEAF OF THE WHITE SPECIES OF SESAMUM INDICUM [LINN] FROM BENUE STATE, NIGERIA.

1C. E. Ogwuche, 2J. O. Amupitan and 2G. I. Ndukwe

1Department of Chemistry, Federal University of Petroleum Resources Effurun, Delta State, Nigeria

2Department of Chemistry, Ahmadu Bello University, Zaria, Kaduna State, Nigeria

Corresponding author: christogwu@gmail.com

Abstract

The leaf of Sesamum indicum L. was obtained from Benue State, Nigeria in August, 2010. The leaf of the plant was air dried under shade, segregated and pulverized. 840.64g of the pulverized plant materials were carefully weighed and loaded into a Soxhlet extractor. It was extracted successively starting with petroleum ether, chloroform, ethylacetate and finally methanol. The Ethylacetate showed the most prominent from the crude antimicrobial screening.. 10.0g of the ethylacetate crude extract was loaded in a column and was developed by gradient elution. The purified sample from the above column chromatography was subjected to preparative TLC. The result gave rise to a deep yellowish oil which was single spot. This oil was further subjected to antimicrobial screening which showed that the pure isolate was active against the microorganisms, Staphylococcus aureus, Streptococcus pyogenes, Salmonella typhi, Candida albicans, Candida krusei, and Candida tropicalis at various MIC’s and (MBC/MFC)’s and was inactive against Bacillus cereus, Corynebacterium ulcerans, and Escherichia coli.. Based on the available spectral data FTIR, 1D NMR and 2D NMR, the structure of the compound was proposed to be a 1, 2, trilinolenyl, 18:3 () triglyceride, a linolenic acid ester.

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