Open Access Original Research Article

Optimisation of Activated Carbon Preparation by Chemical Activation of Ayous Sawdust, Cucurbitaceae Peelings and Hen Egg Shells Using Response Surface Methodology

Ngakou Sadeu Christian, Ngomo Horace Manga, Tchuifon Tchuifon Donald Raoul, Anagho Solomon Gabche

International Research Journal of Pure and Applied Chemistry, Page 1-12
DOI: 10.9734/IRJPAC/2017/36021

Aims: Explore  the  effects  of  the mixture of  biomass materials: ayous sawdust, cucurbitaceae peelings and hen eggs shells in  the preparation  of  activated  carbon  by  chemical activation using  the  Methodology of Experimental Design.

Study Design: Determination of the physicochemical properties of the prepared activated carbons by the mixture of biomass materials: ayous sawdust, cucurbitaceae peelings and hen eggs shells using the Methodology of Experimental Design.

Place and Duration of Study: Laboratory of Noxious Chemistry and Environmental Engineering, Department of Chemistry, University of Dschang, between February 2015 and November 2016.

Methodology: A mixture of ayous sawdust, cucurbitaceae peelings and hen egg shells were used to prepare activated carbon by chemical activation using H3PO4. The effect of the composition of the components on the iodine number of the activated carbon was investigated.  The Methodology of Experimental Design (MED) was used to optimize the production conditions of the activated carbons, while the analysis of variance (ANOVA) was used to determine the significance of the various variables.

Results: Using a carbonization temperature of 450°C and a H3PO4 concentration of 0.79 M, the optimum conditions for preparing the activated carbon were 2 hours of resident time, 0.549 as mass fractions for ayous sawdust, 0.450 for cucurbitaceae and 2.296×10-10 for hen egg shells. The resultant activated carbon was found to have a BET surface area of 311.23 m2/g, an iodine number of 656.70 mg/g and a carbon yield of 44.88%. It was also observed that the experimentally obtained correlation coefficient of 0.999 was in good agreement with the values predicted by the model. The iodine number, which decreased with the fraction of hen eggs shells used portrayed an antagonist effect, while its increase with the increase in ayous sawdust and cucurbitaceae peelings showed the synergetic effect.

Conclusion: The optimized activated carbon was the one produced from the near 50/50 combination of ayous sawdust and cucurbitaceae, and its BET surface area, and iodine number were superior to those from the individual materials.

Open Access Original Research Article

Computational Study on 4-Amino-3-Hydroxynaphthalene-1-Sulfonic Acid (AHNSA)

Getachew Denbela, Ahmed M. Mohammed

International Research Journal of Pure and Applied Chemistry, Page 1-14
DOI: 10.9734/IRJPAC/2017/36284

A computational study on 4-amino-3-hydroxynaphthalene-1-sulfonic acid (AHNSA) has been carried out to investigate formation of poly-(AHNSA), and to obtain binding structures and energies of AHNSA-Ephedrine and AHNSA-Caffeine complexes. For this purpose, the DFT/B3LYP/6-31G(D) and DFT/B3LYP/6-31+G(D) level of theories were utilized. These were investigated from analysis of their atomic charge distributions, total spin density, frontier molecular orbitals, electrostatic potential maps and calculations of binding energies. Results from analysis suggest that homo-polymerization of AHNSA should involve the molecular orbitals arising between radical cations formed from the neutral monomer. The resulting data illustrated that the method was likely to be useful for homo-polymerization of AHNSA. Calculated binding energies of AHNSA-Caffeine and AHNSA-Ephedrine complexes were -8.77 kcal mol-1 and -8.36 kcal mol-1, respectively, which indicated that both complexes could be formed.

Open Access Original Research Article

Computational Investigation on Dipyrido[3,2-a:2’,3’-c]-phenazine and Its Cobalt (II) Complex

Desalegn Nigatu, Ahmed M. Mohammed

International Research Journal of Pure and Applied Chemistry, Page 1-8
DOI: 10.9734/IRJPAC/2017/36481

A density functional theory with hybrid B3LYP method was modeled to predict the molecular properties of dipyrido[3,2-a:2’,3’-c]phenazine (1), and Co(II) complex of dipyrido[3,2-a:2’,3’-c]phenazine (2). The theoretical IR spectra of the studied compounds have been examined. In addition, the 13C and 1H NMR and absorption spectral data have been calculated by B3LYP/ 6-31G(d) methods. Nature of frontier molecular orbitals has been assessed and band gap was calculated for dipyrido[3,2-a:2’,3’-c]phenazine. Electronic and thermochemical properties of the studied compounds were calculated and predicted the possible reaction products.

Open Access Original Research Article

Analytical Method for the Determination of Surfactants with Fluorescent Activity, Present in Liquid Effluents from Textile Industries, by HPLC-Fluorescence

Martínez Ramón Alberto, Fechner Diana Corina, Ruiz Díaz Juan Daniel, Vazquez Francisco Antonio

International Research Journal of Pure and Applied Chemistry, Page 1-10
DOI: 10.9734/IRJPAC/2017/36636

In textile industries effluents we can be found surfactants of various characteristics, alkalis, and sulfides partially or totally hydrolyzed dyes, among other things, which are used as dyeing material. This study aims to create an unconventional tool to evaluate the degree of environmental contamination as a consequence of the discharge of these compounds that constitute the effluents of the textile industry prior to its final disposal, with or without purification systems, following one or more of its constituents possessing fluorescent properties.

It was designed a technique to determine and quantify surfactant compounds used in textile industry. The conditions of the technique by HPLC with fluorescence detector designed are: Mobile phase: H3CCN/NaClO4 (12.3 g/L) 65:35; flow: 1 mL/min; column: Waters Symmetry C18 5 mm; 4.6 x 150 mm; pre-column: Kromasil 100-5C18; λex: 225 nm; λem: 290 nm.

It was found that the commercial textile surfactants analyzed have matching constituents, but also have some unique characteristics that identify and discriminate. Surfactants Tensia MA, Unipal DLE and Croscolor Miro have their own fluorescent compounds, which will be used as contamination indicators to monitor or evaluate the environmental impact of textile effluents on water bodies receiving.

Open Access Review Article

Insights on Fatty Acids in Lipophilic Prodrug Strategy

Elżbieta Dąbrowska-Maś

International Research Journal of Pure and Applied Chemistry, Page 1-10
DOI: 10.9734/IRJPAC/2017/35859

Aim: This review is dedicated to fatty acids importance in prodrugs development strategy. Various strategies of fatty acid-linked prodrugs are discussed in the article.

Summary: The increased drug lipophilicity is of great significance in both blood and lymphatic delivery, as the most desirable physical factor for the specified drug forms. Increased lipophilicity can prolong the action of the drug and enhance drug passive diffusion thorough the biological barriers like skin, gastrointestinal epithelium and blood-brain barrier.

Fatty acids as lipids are present in the human body and occur in the nature, moreover as the esters with steroid hormones also exist naturally.

Thus, the implementation of fatty acids into the prodrug research strategy seems to be the most desirable, especially for the improvement of lipophilicity of the parent drug. The drugs may be linked to the fatty acids either thorough the carboxylate group or by the ω-position.