Physical and Chemical Characterizations of Rubber Latex Cup Bottom Oil

Rubber latex is an important economic resource. However, the residues from its harvesting are thrown away, even though they contain lipids that can be recycled. This recovery of the residues from the bottom of the cup requires first and foremost their characterization. The aim of this study is therefore to determine the main physical and chemical characteristics of rubber latex cup bottom oil. Oil’s physical parameters determination shows that it has a density of 951 kg∙m−3, a kinematic viscosity of 48.57 cSt and a water content of 0.0845%. Chemical parameters, meanwhile, indicate that this cup bottom residue has a fat content of 95.96%, an acid number of 2.805 mg KOH/g and an iodine number of 92.42 g I2/100g. Therefore, rubber latex cup bottom oil can be used in the formulation of biofuels, biolubricants, paints, varnishes, alkyd resins, polishing oils, soaps, and insecticides.

Theoretical Investigation on the Stability and Reactivity of Imidazo [1,2-a] Pyridine N-Acylhydrazone Derivatives Using Density Functional Theory

The reactivity and stability of seventeen (17) imidazo [1,2-a]pyridine N-acylhydrazone derivatives were investigated using density functional theory at the B3LYP/6-31+ G (d, p) level. Analysis of the molecular electrostatic potential (MEP) and determination of the dual descriptor revealed that in most cases, the nitrogen atoms of the 6-πelectron conjugation, the oxygen, and the sulfur atom are nucleophilic site. Chemical reactivity of the compounds was assessed through analysis of frontier molecular orbitals (HOMO and LUMO), energy gap (Δℰ), chemical hardness (η), and the softness (S). Consequently, the compound 9e exhibited the lowest reactivity, least electron donating, and the highest stability. This comprehensive study offers valuable insights into the chemical behavior of these derivatives, crucial for further exploration and potential applications.

Optimization of Biofuel Formulation by Mixture Design

With the full growth of energy needs in the world, several studies are now focused on finding renewable sources. The aim of this work is to optimise biofuel formulation from a mixture design by studying physical properties, such as specific gravity and kinematic viscosity of various formulated mixtures. Optimization from the mixture plan revealed that in the chosen experimental domain, the optimal conditions are: 40% for used frying oil (UFO), 50% for bioethanol and 10% for diesel. These experimental conditions lead to a biofuel with a density of 0.84 and a kinematic viscosity of 2.97 cSt. These parameters are compliant with the diesel quality certificate in tropical areas. These density and viscosity values were determined according to respective desirability values of 0.68 and 0.75.

Formulation of Motor Oil from Blends of Rubber Latex Cup Bottom Oil (RLBO) and Used Frying Oil (UFO)

Most motor oils are made from mineral oils derived from petroleum, the reserves of which are limited and exhaustible. The aim of this study is to produce and characterize motor oil formulations based on mixtures of rubber latex cup bottom oil (RLCBO) and used frying oil (UFO). The results show that these formulations have a density between 0.91 and 0.92. These densities evolve linearly with the proportion of cup bottom oil and temperature. Similarly, the kinematic viscosity of the blends follows an exponential relationship with temperature. By plotting the logarithm of these kinematic viscosities against the inverse of the temperature, we were able to determine the activation energy of the various blends and deduce that the formulations behave Newtonian.

Study of the Viscosity and Specific Gravity of the Ternary Used Frying Oil (UFO)-Bioethanol-Diesel System

Fossil fuels cover around 80% of global energy consumption. However, the problems linked to their use justify the choice of using biofuel. In order to reduce as much as possible, diesel rate, an increase in the number of additives may be considered. Thus, in this work, the study of the used frying oil (UFO), bioethanol and diesel ternary system was undertaken. It emerges from this study that the addition of bioethanol reduces the viscosity and the density of the ternary system and permits a 90% substitution rate for diesel between the UFO and bioethanol. Finally, the percentage of oil becomes 40% after adding alcohol compared to the binary diesel crude vegetable oil mixture where this rate is 30%.

New Triterpenoid Isolated from the Roots of Gouania longipetala Hemsl

Gouania longipetala Hemsl. (Rhamnaceae) is a medicinal plant from Côte d’Ivoire used to treat many diseases like malaria, gastrointestinal infections and gout. Scientific research of aerial part revealed the presence of triterpenoid compounds, saponins, phenolic compounds and flavonoids and also mentioned antibacterial, antioxydant and anti-inflammatory activities. Despite the various therapeutic uses of the plant, no scientific research mentions the chemical content of the root. So, this phytochemical investigation is made to identify secondary metabolites present in the hydromethanolic extract of its roots. And the research led to the isolation and characterization of three lupane-type triterpenoid compounds: a novel compound derived from gouanic acid, lupeol (1) and betulin (2), which had been previously reported in the literature. The newly discovered lupane-triterpenoid was identified as 1α-hydroxy-lup-20(29)-en-3-oxo-27,28-dioic acid (3). The structures of these compounds were determined based on analyses of spectroscopic data, including 1D-NMR, 2D-NMR and HR-ESI-MS techniques.

Evaluation of Total Polyphenol and Flavonoid Contents of Fresh and Dried Pepper (Piper nigrum) from the Ivory Coast

The growing interest in the potential biological activity of polyphenols and flavonoids has highlighted necessity to assess their content in fresh and dried pepper from Ivory Coast. The total polyphenol content was determined using the Folin-Ciocalteu test and the total flavonoid content was also measured spectrophotometrically using the aluminum chloride colorimetric test. The results obtained indicate the total polyphenol levels of fresh and dried peppers are higher in the samples collected in Danane (0.8 ± 0.05 mg GAE/100g) and in Azaguie (0.4 ± 0.08 mg GAE/100g). The lowest concentrations were obtained with fresh and dried pepper samples collected in N’douci (0.22 ± 0.02 mg GAE/100g) and in PK 103 (0.22 ± 0.02 mg GAE/100g). The highest content of total flavonoids was revealed in the locality of PK 103 (1.85 ± 0.62 mg EC/100g) followed by the locality of Maféré (1.37 ± 0.25 mg EC/100g) respectively for black pepper and green pepper. Then, the lowest flavonoid contents were obtained in the dried pepper of Lopou (0.57 ± 0.03 mg EC/100g) and the fresh pepper of PK 103 (0.47 ± 0.03 mg EC/100g). The results obtained highlight the importance of these black spices as promising sources of phenolic compounds and could be used in pharmaceutical treatments and in food.

Production of Cashew Apple Wine Enriched with Hibiscus sabdariffa Extracts

This study focuses on enhancing the value of agricultural products by developing a process to produce wine from cashew apples enriched with extracts from Hibiscus sabdariffa. The formulation consisted of a blend of cashew apple juice and Hibiscus calyxes in a ratio of 90:10 (w/w). The Hibiscus calyxes were added at three different stages: before, during, and after fermentation. The physico-chemical analysis of the resulting wines revealed a pH range of 3.073 ± 0.005 to 3.583 ± 0.015 and acidity levels ranging from 4.018 ± 0.028 to 5.628 ± 0.059 g/L. The alcoholic strength ranged from 13.54% ± 0.036% to 13.86% ± 0.04%, with a soluble dry extract of 7.2 ± 0.25 to 8.1 ± 0.28 °B. Regardless of the stage of Hibiscus calyx addition, the fermentation kinetics and physico-chemical parameters met the standards set for wines.

Compositional, Structural, Surface Characterizations of Natural Magnetite from Air Massif (Niger) in Relation to Its Catalytic Activity

Ferrimagnetic materials such as natural magnetite are used for practical applications because of their electronic, magnetic and catalytic properties in the degradation of organic compounds. In order to determine its physicochemical properties in relation to its catalytic activity, the natural magnetite of Ofoud Mount (Niger) is characterized by X-ray florescence (XRF), X-ray diffraction (DRX), specific surface area (BET) and Fourier transformed infrared (FTIR). The result shows an iron content of 97.09% and a specific surface area of 69.742 m2/g. The crystal structure of magnetite is cubic with lattice parameters α = β = γ = 90°, a (Å) = b (Å) = c (Å) = 8.3740. The results of this study suggest that the natural magnetite of Ofoud Mount can be used as iron source in various fields of science despite the presence of a few impurities that can improve its catalytic activity.

Hypotensive Effects of an Aqueous Extract of Bambusa vulgaris (Poaceae) Leaves in Rabbit Oryctolagus cuniculus

Plant of Bambusa vulgaris is used in traditional medicine practice for the management of many pathologies including hypertension. The effect of the aqueous extract of the leaves of Bambusa vulgaris on blood pressure was evaluated in normotensive male rabbits. Blood pressure was measured by the invasive method. Thus, aqueous extract of Bambusa vulgaris leaves had been injected intravenously at doses ranging from 1 mg/kg to 30 mg/kg in rabbits anesthetized with thiopental. The effects of this extract on blood pressure were also evaluated in rabbits having previously received different doses of atropine. The aqueous extract of Bambusa vulgaris leaves induced a dose-dependent hypotension which is not canceled in the presence of atropine. The results obtained show that the extract has blood pressure lowering effect which may be mediated by muscarinic-type cholinergic receptors.

Evaluation of the Nutritional Quality of Red and Refined Palm Oils Marketed in Yamoussoukro (Côte d’Ivoire)

In order to define the nutritional quality of commercialized red and refined palm oils, palm oil samples conditioned or not with aluminum foils were placed in solar radiation for four weeks. Each week, the levels of peroxides, free and unsaturated fatty acids and then vitamins A and E were determined. From these analyzes, the proportions of peroxides and free fatty acids increased with solar exposure time of the oils. These rates ranged from 0.11 to 24.00 meq O2/Kg (peroxides) and from 1.11 to 17.14 KOH/g (free fatty acids). Also, iodine index levels of palm oils decreased during sun exposure “95.11 - 3.22 g I/100 g”. In addition, vitamin A and E losses from palm oil samples increased with exposure time. These losses ranged from 0% to 94.49% for vitamin A and from 0% to 83.42% for vitamin E from the day of purchase of oils in the fourth week of sun exposure. However, the deterioration of nutritional quality was greater with red and refined palm oil samples unprotected with aluminum foils than those protected.

Dimensioning of an Anaerobic Digester for the Treatment of Chicken Manure and for the Production of Biogas: The Case Study of a Chicken Farm in Yaokokoroko (Côte d’Ivoire)

This study allowed us to highlight the level of pollution of a BAYA River water near several poultry farms and the sizing of an anaerobic digester that will be able to treat chicken manure from a poultry farm (BRIN FOUNDATION). To evaluate this pollution, the parameters such as ammonium (NH4+), Phosphate (PO43-), Biochemical Oxygen Demand (DBO5) and Nitrate (NO3-) were determined. For sampling point P1, the concentrations in mg/L of these parameters are (25.00 ± 4.25), (0.40 ± 0.20), (98.00 ± 6.35) and (96.00 ± 5.35), respectively. On the other hand, for sampling point P2, the concentrations in mg/L of these parameters are respectively (33.00 ± 9.05), (0.70 ± 0.12), (123 ± 7.13) and (93 ± 7.10). These values indicate a strong organic pollution of the BAYA River. The determination of the different concentrations of the organic pollution parameters allowed us to evaluate the degradation and the quality of the water of the BAYA River water, by the poultry activity. However, considering the physicochemical properties of the waste (chicken manure), which is the main source of organic pollution, we have considered an energy recovery through the production of biogas. This requires the design, sizing, and implementation of an anaerobic digester in a poultry farm. Therefore, the project would require the construction of an adapted masonry type anaerobic digester with a capacity of 10 m3.

Optimization of Preparation Conditions of Activated Carbons Based on the Shells of Ricinodendron heudoltii

The purpose of this work is to prepare better activated carbons from the shells of Ricinodendron Heudelotii by chemical activation with sulfuric acid (H2SO4) and sodium hydroxide (NaOH). The process was optimized by a full factorial design (2K) based on the analysis of the external specific surface area of sixteen (16) activated carbons prepared according to the parameters of the preparation. This active analysis reveals that under the preparation conditions, good carbons are obtained for a sodium hydroxide concentration equal to 1 M, an impregnation time of 24 h and carbonization at 500˚C for 1 h. The external specific surface of this carbon is 358 m2 • g-1. The characteristics of this prepared carbon are as follows: a pH at zero point charge (pHpzc) of 8.2, a predominantly amorphous structure, a basic character and a low ash content (4.2%). It also has surface functions;the lactonic and carbonyl groups (C=O) at 1600 cm-1 and the carboxylate groups (O-H or C-O) at 1340 cm-1.

Novel Mannich Bases of Benzimidazole Derivatives: An Antibacterial Study of Environmental Bacterial Strains

A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylbenzimidazole and 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl)benzimidazole derivatives possess antibacterial activities against clinical strains, such as Escherichia coli, Klebsiella pneumonia (Gram-negative bacteria), Staphylococcus aureus and Pseudomonas aeruginosa (Gram-positive bacteria). Following these favorable results, we extended the antibacterial evaluation of this series of molecules to environmental strains. The aim of this study was to assess the impact of the methyl-piperidine group fixed at position-1 of this new series of benzimidazoles on the antibacterial activity of environmental strains. In addition, we first evaluated the antibacterial activity of four 2-(thioalkyl)methylbenzimidazole derivatives and then that of five 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives. This study allowed us to show that compounds 1d and 1e could inhibit bacterial growth in vitro of the Enterobacteria P1 strain with inhibition diameters of 17.3 ± 0.6 mm and 10 ± 0.0 mm, respectively. However, addition of methyl-piperidinyl in this series showed that five (5) of 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives had an inhibitory effect on the in vitro growth of bacterial strains used except on Enterobacteria P2 with inhibition diameters between 10.0 ± 0.8 mm and 27.9 ± 1.4 mm. The introduction of the methyl-piperidinyl group at the 1-position of 2-(thioalkyl)-1H-methylbenzimidazole derivatives greatly improved the antibacterial activity against environmental bacteria such as Escherichia coli A1, A2, A3, and A4 and two Enterobacteria P1.

Modeling and Optimization of Two Clays Acidic Activation for Phosphate Ions Removal in Aqueous Solution by Response Surface Methodology

This work deals with phosphate ions removal in aqueous solution by adsorption carried out using two clays, both in activated form. One, non-swelling clay, rich in kaolinite, is associated with illite and quartz. The other, swelling, richer in montmorillonite, is associated with kaolinite, illite and quartz. Seven factors including these two clays were taken into account in a series of experimental designs in order to model and optimize the acidic activation process favoring a better phosphate removal. In addition to the choice of clay nature, the study was also interested in the identification of the mineral acid, between hydrochloric acid and sulfuric acid, which would promote this acidic activation. Response Surface Methodology (RSM) was used for this purpose by sequentially applying Plackett and Burman Design and Full Factorial Design (FD) for screening. Then, a central composite design (CCD) was used for modeling the activation process. A mathematical surface model has been successfully established. Thus, the best acidic activation conditions were obtained by activating the montmorillonite clay with a 2N sulfuric acid solution, in an acid/clay mass ratio of 7.5 at 100°C for 16H. The phosphate removal maximum rate obtained was estimated at 89.32% ± 0.86%.

Abundance and Source Identification of Polycyclic Aromatic Hydrocarbons in Sediments of the Ivory Coastal Zone (Toukouzou Hozalem-Assinie)

Polycyclic aromatic hydrocarbons (PAHs) are strongly associated with agricultural, residential, transportation, industrial and petroleum activities. In this study, the presence of PAHs (polycyclic aromatic hydrocarbons) was investigated in sediments of the ivory coastal zone (Toukouzou Hozalem-Assinie). The main objectives of this study were to determine the abundance and to predict the source of PAHs in the sediments. Gas chromatography-mass spectrometry (GC-MS) was used to analyze sixteen priority PAHs. Total PAHs concentrations were from 1.31 to 3992.68 mg/kg in sediment with an average concentration of (307.54 ± 16.10) mg/kg. Among all PAHs, Naphthalene (Nap = 332.72 mg/kg) and Phenanthrene (Phe = 41.75 mg/kg) were found in the highest concentration, whereas Benzo (k) Fluoranthene was found in the least concentration in the range of 0 - 0.85 mg/kg (mean 0.24 mg/kg). Bassam-Modeste Lagune (BML) sampling site was the site with the highest concentration of total PAHs (all 16 PAHs) compared to the others due to their location in a highly populated estuary area that receives commercial, tourism, port, petroleum and heavy industrial activities. Diagnostic ratios were used to determine the sources of PAHs and suggested that the PAH profile in the sediments was dominated by 2 and 3 ring PAHs. The patterns of PAH compounds in sediment indicated that contamination is from mixed sources, with a strong indication of petrogenic contamination potentially from spills of fuel, oil and industrial activities.

Diagnosis of Wastewater Contamination by Metalic Trace Elements (MTE) in the Areas of Yopougon (South Abidjan) and Marcory, Koumassi (North Abidjan) from March to July 2021

Contamination of the aquatic environment by Metallic Trace Elements (MTE) is a major problem encountered in our environment today. In Côte d’Ivoire, in some municipals, residential and industrial areas in the city of Abidjan, waste water of worrying quantity is discharged into the rainwater drainage channels which flow directly into the Ebrié lagoon. In order to identify the origin of the pollution by metallic trace elements (MTE) transported by this water, samples of wastewater were collected and then analyzed. ICP-MS was used for MTE (Cu, Fe, Zn, Al, Pb, Cd) analyses and results were statistically processed in multivariate form using PCA and Excel. The results showed high concentrations of metals, with the exception of Cd. The typological structure represents 85.74% of the total information for the MTE. Plan F1 represents 63.90% of the variance and describes water pollution by copper (0.95), zinc (0.90), iron (0.84) and aluminum (0.84). Plan F2 represents 21.84% and describes the enrichment of water with lead (0.84). It seems more than necessary to make manufacturers aware of the need to install wastewater treatment systems in order to avoid their discharge into the environment.

Analysis of the Technico-Economic Viability of an Electric Micro-Grid with Renewable Electricity Production Sources in Elokato-Bingerville, Cote d’Ivoire

In this study, the technico-economic viability is studied, on the basis of different scenarios of electric micro-grids with renewable energy production sources, autonomous and supplied by the interconnected grid. HOMER Pro 3.13.3 Pro simulation and optimization software, Xlstat and Energy sentinel software are used for the evaluation of different technical and economic scenarios of system components, in order to obtain the most cost-effective configuration. To do this, the case study of the village of ELOKATO identifies the optimal options for the use of renewable energies for rural electrification in order to increase the electricity coverage rate. In our case study, after the various simulations, HOMER identified 13 scenarios and configurations deemed to be the most profitable, from the parameters and configurations without photovoltaic components have high COEs and very high initial investment costs in the order of several million US $. Renewable energy power generators require high initial investments and relatively low operating costs. The most important costs are generated by the battery park and then come the photovoltaic panels. The hybrid PV/wind/diesel/hydropower system is profitable if the distance from the village to the transformer station is greater than 1.90 km. The results show great potential for using these hybridized production sources with or without a generator to meet the electricity needs of a village.

Assessing Levels and Health Risks of Fluoride and Heavy Metal Contamination in Drinking Water

A systematic study was carried out to assess the level of contamination with fluorides and heavy metals in the drinking water of the city of Daloa as well as the risks to the health of consumers. The waters of 11.11% of the sites sampled exceeded the fluoride limit for drinking water with a contamination index (CI) greater than 0. All the waters recorded concentrations of cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn) and lead (Pb) above the recommended values with CI > 0. However, 22.22% of the sites recorded concentrations below the standard for zinc (Zn) with IC < 0. The assessment of adverse effects on human health showed that the chronic daily intake (CDI) of fluorine and metals was less than 1 (CDI < 1) for both adults and children except for Zn where the CDI > 1 for children in 22.22% of drinking water studied. HQs have an average of less than 1 for fluorine and greater than 1 for all metals. Moreover, the danger indices have values greater than 1. The incremental lifetime cancer risk (ILCR) and the total ILCR are above the recommended values. These results showed that the drinking water sampled is of poor quality due to higher levels of heavy metals, which can constitute a danger to human health. Long-term use of one of these poor quality waters can lead to cancer in consumers. It is therefore necessary to treat this water in order to eliminate the metals before using it for drinking. This study can help decision-makers and competent authorities in charge of water management.