Open Access Original Research Article

Photocatalytic Degradation of Rhodamine-B Under UV-Visible Light Irradiation Using Different Nanostructured Catalysts

María del C. Cotto-Maldonado, Teresa Campo, Eduardo Elizalde, Arancha Gómez-Martínez, Carmen Morant, Francisco Márquez

Chemical Science International Journal, Page 178-202
DOI: 10.9734/ACSJ/2013/2712

Aims: The goal of this research is to determine the efficiency of different catalysts for the degradation of organic compounds as possible alternative for wastewater treatments. To reach this goal, many objectives should be previously satisfied including the synthesis of different catalysts and the catalytic tests for the different processes.

Study Design: A multifactorial design was used for the experimental study.

Place and Duration of Study: The present study was conducted between January 2011 to December 2011 at the School of Science and Technology, Universidad del Turabo and the Department of Applied Physics at the Universidad Autónoma de Madrid, Spain.

Methodology: Different catalysts were synthesized and the photocatalytic activity was measured. Catalysts were characterized by XRD, FE-SEM, SBET and TGA. For the photocatalytic activity a cylindrical reactor with continuous stirring was used. The dye (10-5 M) was previously dissolved in water and 0.6g L-1 of the corresponding catalyst was added to the reaction mixture. An irradiation of 60 watts was applied. An aliquot of 10 mL was taken every 10 min during a period of an hour from the solution and diluted for characterizing by UV-vis and fluorescence spectroscopies and TOC.

Results: The catalytic tests indicate that TiO2NWs is the most efficient catalyst and eventually could be used for alternative wastewater treatments.

Conclusion: Synthesized (TiO2NWs, TiO2@MWCNTs and ZnO) and commercial catalysts were fully characterized by FE-SEM, TGA, specific surface area (BET) and XRD. The most efficient catalyst was TiO2NWs (with approximately 96.44% of degradation). All catalysts used were able to degrade the Rhodamine-B and could eventually be used to removal pollutants from water.

 

Open Access Original Research Article

Synthesis and Cytotoxicity of Some New Substituted Hydronaphthalene Derivatives

Mogedda E Haiba, Ebtehal S Al-Abdullah, Noha Mohamed Hilmy

Chemical Science International Journal, Page 203-220
DOI: 10.9734/ACSJ/2013/3452

A new series of hydronaphthalene derivatives incorporated into or fused to different five or six membered nitrogen, oxygen, sulpher, heretrocyclic, S- glycosidic or N-glycosidic moieties and other related products had been described. The hydrazine derivative 2 was coupled with bromo-sugar to achieve N-glycosides in presence of acidic medium while, the products 4 and 15 were coupled with different bromo sugar achieving S-glycosides in presence of a basic medium. Moreover, other derivatives carrying different biologically active side chains and hetero cyclic substituents were synthesized starting with 6-methoxy-1-tetralone 1. Also, the X-ray data of compound 13c was studied. The cytotoxicity of some of the newly synthesized compounds was studied to evaluate their in-vitro inhibitory effects against cellular proliferation in human cultured breast carcinoma cell lines. It has been found that the chalcone derivatives 13a-c and their cyclized thiopyrimidine analogues 14a, b appeared to be potent breast carcinoma growth inhibitors comparing to Doxorubicin.

 

Open Access Original Research Article

Effectiveness of Contact Devices on Ethanol Separation Efficiency in a Packed Distillation Column

Adeyemi O. Adepoju, Elijah A. Taiwo

Chemical Science International Journal, Page 221-231
DOI: 10.9734/ACSJ/2013/3175

Aims: To obtain the distillation column efficiency as a function of the packing materials used at various feed compositions of binaries and a ternary system to validate the most effective packing arrangement.

Study Design: The design was based on the concentrations obtained from the fermentative production of ethanol. 

Place and Duration of Study: Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria, between December 2009 and August 2010.

Methodology: Distillation experiments were carried out with three binary systems (ethanol-water, ethanol-ethylene glycol and water-ethylene glycol) and a ternary system (ethanol-water-ethylene glycol) in a 0.1m internal diameter glass column which was first packed with 8mm diameter Raschig rings (A) thereafter, same size of wire gauze rings (B) and later their combination (C). The experiments were performed under total reflux conditions and at atmospheric pressure.

Results: Out of the three packing arrangements investigated, Packing-B showed the best performances with the number of transfer units from 2.8818 to 1.9556 and 4.0723 to 3.0845 corresponding to ethanol-water and ethanol-ethylene glycol binary systems respectively, in the direction of increasing most volatile component (mvc) in the charged compositions. Whereas, for water-ethylene glycol system, opposite trend was obtained. Also, the best efficiencies (0.5652 to 0.9842) were exhibited by Packing-B. The results obtained for the ternary system revealed an inverse relationship between the mvc in the charged composition and the ethanol component efficiencies for all the packing used. This showed that the component efficiencies were higher for Packing-B (3.0157 to 1.5038) than Packing-A (2.7393 to 1.4595) and Packing-C (2.8116 to 1.4721). T-Test showed significantly different efficiencies for only ethanol-water pair-wise comparisons as well as for Packing- A and Packing-B in the ethanol-ethylene glycol system.

Conclusion: The designed wire gauze ring packing (Packing-B) has offered higher separation for all the systems examined than the conventional raschig ring. Thus, offering research basis for improving upon locally fabricated packing devices for bio-ethanol industry.

 

Open Access Original Research Article

Assessment of the Global Solar Energy Potential at Nigerian Defence Academy (NDA) Permanent Site Afaka Kaduna, Nigeria

I. Hassan, M. Y. Onimisi

Chemical Science International Journal, Page 232-246
DOI: 10.9734/ACSJ/2013/3475

This paper assessed the global solar radiation potential in Nigerian Defence Academy, (NDA) permanent site Afaka Kaduna, North west Nigeria, for the period of March, April and May 2012. The cantonment lies exactly between longitudes 7º 12’E to 7º 35’E of the Greenwich meridian and latitude 10º 36’N to 10º 42’N of the equator. Procedure employed involved the use of Hargreaves-Samani’s equation as a method of estimating solar radiation using minimum climatological data. The global solar radiation at NDA Kaduna within the period of study exhibits monthly variation, with mean values of 20.11±0.04, 20.14±0.04 and 20.18±0.04 MJm-2Per day respectively. The study makes use of a statistical model that adopts the available data to assess the global solar radiation at NDA, permanent site Afaka, Kaduna for the months of March, April and May, 2012.The information from the studies conducted goes a long way to establish solar irradiation data on the region studied which then forms a baseline for any planned application of solar irradiation in the area. Meanwhile the information will also assist the policy makers in the academy to know exactly the particular days and time in the months under investigation when not to expose the military personnel and cadets to vigorous military training. Simply because it’s the period of maximum sun shine in the region.

Open Access Original Research Article

Characterization Studies of Aluminum Alloy Substrate Surfaces Treated By Oxyanion Esters of Α-Hydroxy Acids and Their Salts

Volkan Cicek

Chemical Science International Journal, Page 264-286
DOI: 10.9734/ACSJ/2013/3823

In this investigation, first, substrate coupons of commonly used alloys of Aluminum, which are 2024, 6061 and 7075 alloys, were immersed in solutions of inhibitors such as gluconate esters having the formula of (M)x(hydroxyacid)y(M‘aOb)z combining constituents that are already known for high inhibition efficiencies such as hydroxyacids and metal oxyanions. Among other inhibitor solutions used were benzilate esters, gluconate salts, zinc carboxylates, etc. Secondly, after immersions of the mild steel coupons in inhibitors solutions of varying concentrations for different periods of time, they were characterized by means of various surface techniques such as FT-IR, X-Ray, SEM, XPS and digital imaging. As a result of use of these characterization techniques, it is decided whether protective layers of inhibitor compounds are formed on the substrate surfaces due to immersions in the solutions of the inhibitor compounds similar to those of conversion coatings. The results have proven individual consequences for each inhibitor tried and are described in detail herein the paper, which assisted in the assessment of aqueous corrosion inhibition mechanisms of mild steel by oxyanion esters of α-hydroxy acids and their salts.

 

Open Access Original Research Article

XRD Characterization of Sand Deposit in River Niger (South Eastern Nigeria)

Ekpunobi Uche Eunice, Duru Chiamara Blessing, Obumselu Fabian

Chemical Science International Journal, Page 287-293
DOI: 10.9734/ACSJ/2013/3250

In this study the sand deposits from River Niger in Anambra State, South Eastern Nigeria, were characterized for its potential utilization as industrial raw materials for ceramics and enamel wares. Physical, chemical and mineralogical characteristics of the sand sample (A) were determined. X-ray diffraction (XRD) was used in the mineralogical characterization. Results obtained were analyzed using Bragg-Wolf equation and International Centre for Diffraction Data software. The results show that the sample contain the phyllosilicate minerals of mica group and identified as shirozulite (KMn3 [Si3Al]O10[OH]2) a new manganese dominant of monoclinic arrangement. The physico-chemical analysis of the deposits corroborates the XRD results. The results concluded that the samples could be utilized as industrial raw materials for ceramic and enamel wares.

Open Access Original Research Article

Effect of Different Disinfecting Agents on Heavy Metals During Water Treatment

Mohammed A. Hussein, Abd EL-hafeez El- Seheimy, Mohamed El Sayed, Mahmoud M. El haloty, Wael M. Kamel, Yasser H. Mohamed, Noha E. Ibrahim

Chemical Science International Journal, Page 294-306
DOI: 10.9734/ACSJ/2013/2711

Aims: The aim of this study to evaluate the effect of huwa-san and chlorine as disinfecting agents on heavy metals during water treatment.

Place and Duration of Study: Department of Biochemistry, Faculty of Pharmacy, October 6 university (Medical Unit IV) and Inorganic laboratory, Central laboratory, Greater Cairo Drinking Water Company, Fustat water treatment plant, between June 2012 and Jan. 2013.

Methodology: Nile water samples were taken from water intake throughout the fustat plant, treated with different doses of huwa-san and chlorine to evaluate their effect on the levels of water contained from Al, Zn, Cr, Ni, Fe, Pb and Cu. 

Results: It was found that the treatment with huwa-san more effective than chlorine in decreasing Al, Zn, Cr, Ni and Cu at the most doses. Also, it is more effective than chlorine in decreasing Fe and Pb concentrations at the doses 2, 3, 4, 5 and 6 ppm while at the dose 7 ppm, the chlorine becomes more effective than huwa-san in decreasing concentration of these elements. Mn showed different results. The chlorine decreased Mn obviously more than huwa-san at all the doses. On the other hand, both of chlorine and huwa-san have the same effect on Zn only at the doses 2 and 3 ppm. The chlorine decreased Ni concentration more than huwa-san at the doses 2 and 3 ppm but huwa-san becomes more effective at the other doses. The results showed that the disinfection with huwa-san more effective results than chlorine at the same doses. 4 ppm of huwa-san represents the most suitable disinfection dose used during the treatment process.

Conclusion: The results showed that the disinfection with huwa-san more effective results than chlorine at the same doses. 4 ppm of huwa-san represents the most suitable disinfection dose used during the treatment process.

Open Access Original Research Article

Deposition and Characterization of Silver Oxide from Silver Solution Recovered from Industrial Wastes

U. E. Ekpunobi, O. K. Okwukogu, A. I. Anozie, A. S. Ogbuagu, V. I. Ajiwe, C. I. Nweze

Chemical Science International Journal, Page 307-313
DOI: 10.9734/ACSJ/2013/3214

Aims: To recover silver from industrial waste and use its solution in silver oxide deposition.

Study Design: Extraction, electrodeopsition on different substrates, XRD and topographical characterizations.

Place and Duration of Study: Sample: x-ray films were collected from Anambra State University Teaching Hospital, Awka, Nigeria. Electrodeposition at Physics and Industrial Physics Department, Nnamdi Azikiwe University, Awka. XRD characterization was done at Energy centre, Obafemi- Awolowo University, Ile-Ife, Nigeria in September.

Methodology: Silver was recovered from x-ray films by dissolving the silver compounds with concentrated nitric acid. The solution thus formed was used as electrolyte in the electrodeposition of silveroxide. Two metallic substrates (zinc and lead) were used for the electrodeposition both serving as cathode while a copper electrode served as the anode. Structural and topographical characterizations were done using XRD and micrograph techniques.

Results: From the result, it was observed zinc substrate gave a good deposition of silver oxide without any impurities whereas the lead substrate gave deposition of silver oxides with lots of impurities

Conclusion: Silver was successfully recovered from wastes and the solution used in silver-oxide deposition.

 

Open Access Original Research Article

Synthesis and a Preliminary Characterization of Poly(Propylene)Imine Hexadecylamine Dendrimer (DAB-Am-16) Modified with Methyl Acrylate

Devaney Ribeiro do Carmo, Tayla Fernanda Serantoni da Silveira, Rosângela Silva de Laurentiz, Urquisa Oliveira Bicalho, Leandro Martins, Newton Luiz Dias Filho, Leonardo Lataro Paim

Chemical Science International Journal, Page 314-324
DOI: 10.9734/ACSJ/2013/3818

This paper describes the reaction of a Poly(propylene)imine hexadecylamine dendrimer (DAB-Am-16) with methyl acrylate. The modified dendrimer obtained (DKMA) was characterized by vibrational spectroscopy, nuclear resonance magnetic (13C), thermogravimetry and scanning electron microscopy. The dielectric properties of DKMA were studied in a temperature range of -40 to 100°C varying the frequency from 10 to 1000 KHz. A relative thermal stability was found for DKMA. The modified dendrimer behaved as an organic insulating (ε' = 5.1). The synthesis performed at basic medium results in a corresponding change in the conformational property of the precursor. The electron microscopy indicated that the dendrimer presented a modified collapsed shape, expected by the proposed route of synthesis.

Open Access Original Research Article

Investigation of the Optical and Dielectric Properties of the Urea L-malic Acid NLO Single Crystal

Sagadevan Suresh

Chemical Science International Journal, Page 325-337
DOI: 10.9734/ACSJ/2013/3503

Single crystals of urea L-malic acid were grown by the slow evaporation technique. The single crystal X-ray diffraction analysis reveals that the crystal belongs to the monoclinic system. The optical transmission study reveals the transparency of the crystal in the entire visible region and the cut off wavelength has been found to be 210 nm. The optical band gap is found to be 5.90 eV. Optical constants such as the band gap, refractive index, reflectance, extinction coefficient and the real (εr) and imaginary (εi) components of the dielectric constant and electric susceptibility were determined from the UV-VIS-NIR spectrum. Dielectric constant and dielectric loss of urea L-malic acid are measured in the frequency range from 50 Hz to 5 MHz at different temperatures. The relative second harmonic generation efficiency of urea L-malic acid crystal has been tested by Kurtz-Perry powder technique.

 

Open Access Original Research Article

Extraction, Preconcentration and Spectrophotometric Determination of Ethylene Glycol in Antifreeze Samples

Hijran Sanaan Jabbar, Azad Tawfiq Faizullah

Chemical Science International Journal, Page 338-355
DOI: 10.9734/ACSJ/2013/3675

Aims: Using a simple and sensitive spectrophotometric method for the indirect determination of ethylene glycol by Malaprade reaction. The method was based on the extraction and preconcentration of iodine.

Place and Duration of Study: Samples: Antifreeze samples were purchased from markets (Erbil, Kurdistan region, Iraq), between April 2011 and August 2011.

Methodology: A method was developed for the determination of ethylene glycol (EG) in antifreeze samples. The method was based on the oxidation of EG with excess potassium periodate in slightly acidic medium; then, extraction and preconcentration of iodine was formed from the reaction of remained periodate with iodide. The decrease in the absorbance of extracted iodine is used to monitor the reaction spectrophotometrically at 515 nm.

Results: The optimum reaction conditions and other analytical parameters were evaluated. Beer’s law is obeyed in the concentration range of 0.2–10 µg/ml (R= 0.9963) and 7.0–36 µg/ml (R= 0.9964) with detection limits of 0.08 µg/ml. The effect of interfering species on the determination is described.

Conclusion: Through the proposed method, a sensitive, low cost, selective, accurate and precise method has been described for the determination of ethylene glycol in antifreeze samples with no interferences from antifreeze additives.

Open Access Original Research Article

The Study of Nucleophlic and Electrohilic Reaсtions of Bis- and 3-Substituted Chroman-2, 4-Dions

A. A. Shkel, O. A. Mazhukina, O. V. Fedotova

Chemical Science International Journal, Page 356-363
DOI: 10.9734/ACSJ/2013/4645

Aims: Here we study nucleophilic and electrophilic reactions of bis- and condensed 3-substituted chroman-2,4-dions to produce polychromeno (thio)pyrans and trioxaoxonium benzonaphthotetracene salts.

Place and Duration of Study: Saratov State University, Chemistry Institute, between September 2011 and July 2012.

Results: Reactions of phenylmethylene bis-chroman-2,4-dion, 3-substituted chroman-2, 4-dion with nucleophilic and electrophilic reagents were studied. Intramolecular O-heterocyclization to polyheteronuclear systems with key chromeno (thio) pyrano fragments of various saturation degrees is shown to be characteristic of the compounds studied. It is noted that phenylmethylene bis chroman-2,4-dion, under the action of phosphorus pentasulfide and hydrogen sulfide in situ, forms bis chromeno thiopyrans.

Conclusion: Optimal heterocyclization conditions for 3-substituted chroman-2,4-dion with boron trifluoride etherate to trioxaoxonium benzonaphthotetracene salts were found.

 

Open Access Review Article

An Overview on Manganese in Nature

Gina Vasile Scăeţeanu, Leonard Ilie, Cătălina Călin

Chemical Science International Journal, Page 247-263
DOI: 10.9734/ACSJ/2013/3748

Manganese is the most 12th prevalent element on Earth that occurs in 11 oxidation states (from -3 up to +7). An essential element present in all living organisms, manganese is required for growth, development and maintenance of health. It is naturally present in soil, plants, water.

In soil, it occurs as exchangeable manganese, manganese oxide, organic manganese and a component of ferromagnesian silicate minerals. The amount of available manganese is mostly influenced by soil reaction, organic matter content, moisture and soil reaction.

In plants, it activates a large number of enzymes that catalyzes oxidation-reduction processes, decarboxylation, fatty acids synthesis or hydrolysis. Plants absorb divalent form of manganese from soil solution. Mn+2 suffer easily an oxidation process to Mn+3 and Mn+4 and due to this behavior are involved in redox processes.

Manganese deficiencies appear usually on acidic soils, low in native Mn or soil with pH above 6.5, poorly drained calcareous soils and organic matter rich. Symptoms of manganese deficiency include interveinal chlorosis with dark-green veins.

In human body, the role of manganese as co-factor for enzymes represent one of the most important functions of this element. Mn-dependent enzymes are oxidoreductases, transferases, hydrolases, lyases, isomerases, meanwhile manganese metalloenzymes include arginase, glutamine-synthetase, phosphoenolpyruvate decarboxylase, Mn-superoxide dismutase.  Manganese deficiency in humans is uncommon, but high levels lead to manganism with manifestations similar to Parkinson disease (generalized bradykinesia and widespread rigidity). Unlike idiopathic Parkinson’s disease, patients with manganism may have a less frequent resting tremor, more frequent dystonia, easily fall backward and failure to respond to levodopa.

The uses of manganese are manifold and include steel production, production of potassium permanganate, glass, textile bleaching. Manganese coordination compounds present antimicrobial properties or are used in magnetic resonance image of the liver.

Taking into account that manganese presents a significant role for plants and human beings, this paper present a review of literature that illustrates the importance of manganese.