This study aimed to describe the behavior of ginger, and to predict its water content, during artificial drying under four temperatures (60 oC, 80 oC, 100 oC, 120 oC). Experiments were carried out on ginger using a DRY-Line type oven. The obtained data was fitted using 4 semi-empirical thin layer drying models. Among the semi-empirical models considered, the diffusion approach model was chosen as the most appropriate model to describe the behavior of ginger. For the different temperatures, he presented respectively the coefficients (r) of 0.9970; 0.9974; 0.9949 and 0.9942; the coefficients Chi-square (χ²) of 4.0306 X 10-6, 3.7015 X 10-7; 1.6387 X 10-7 and 1.3637 X 10-6 and Root Mean Square Errors (RMSE) of 3.5851 X 10-4; 1.1415 X 10-4; 9.2226 X 10-5 and 2.6604 X 10-4 for the four temperatures. The diffusion coefficient varies from 9.585 X 10-9 to 3.466 X 10-8 m2/s and strongly depends on the drying temperature. The activation energy is estimated at 24.188 kJ/mol.

The main objective of this study is to prepare activated carbon based on corn cobs with excellent adsorbent properties. To do this, a plan of experience was applied to 16 coals prepared with KOH and H3PO4 at different temperatures and concentrations. The plan of experience revealed that KOH, 1M carbon with a specific surface of 546.77 m2/g is the best. Experience has shown that H3PO4, 2M has a specific surface of 613.14 m2/g. The carbon activated by H3PO4 was characterized by determining the iodine number, the ash content, the surface functions, the pHzc and scanning electron microscopy (SEM). The results showed that activated carbon has a high iodine number (674.506 mg/g) and low ash content (6%). In addition, the carbon is acidic and has a porous surface.

The aim of this study is to compare a greenhouse solar drying simulated by a developed numerical model, with the actual experimental drying of cocoa beans. Thus, using multiphysical models (based on conservation laws of energy, mass and momentum within the dryer and beans), it was possible to simulate the greenhouse drying behavior of the beans. The resolution of the developed equation system was done using the finite element method of COMSOL Multiphysics 4.0 software. For the validation of the numerical model, an experimental study has been developed at the designed dryer. In this study, a drying operation of cocoa beans was conducted. The characteristics of the drying air (temperature, relative humidity and speed) as well as the mass of the beans were regularly determined over time. The results indicate that, in general, there is good agreement between the experimental results and the simulated results (R close to unity). This allows a validation of the mathematical model of the drying of cocoa beans within the greenhouse type solar dryer used.

The copper corrosion inhibition in one molar nitric acid by cefpodoxime drug is studied via mass loss technique at 303-323K and quantum chemistry. The results show that the studied drug is an efficient inhibitor which adsorbs spontaneously on copper through Langmuir model. Thermodynamic adsorption functions and activation ones were determined and analyzed. They indicate a predominant physisorption process and an endothermic dissolution process. Scanning electron microscopy was used to characterize the metal surface. Quantum chemical calculations at B3LYP level with 6-31G (d, p) basis set lead to molecular descriptors such as EHOMO (energy of the highest occupied molecular orbital), ELUMO (energy of the lowest unoccupied molecular orbital), ΔE (energy gap) and μ (dipole moment). The global reactivity descriptors such as χ (electronegativity), ƞ (hardness), S (softness) and ω (electrophilicity index) were derived using Koopman’s theorem and analyzed. The local reactivity parameters including Fukui functions f(r ⃗) and local softness s(r ⃗) were determined and discussed. Theoretical results were found to be consistent with the experimental data.

Three physico-chemical characteristics of Acacia activated charcoals were determined: the degree of activation, the specific surface and surface functions. The coals are prepared from Acacia auriculaeformis and Acacia mangium, leguminous and fast growing trees, available in Côte d’Ivoire. They were activated by chemical means, by impregnation with phosphoric acid (H3PO4). Analysis of the results indicates that the activation yields are below 50% for both types of coal. In addition, the activated carbon-based Acacia auriculaeformis has a larger surface area than that based Acacia mangium. The two activated coals have mixed surface functions, predominantly acid, which give them a dual reactivity for both anionic and cationic adsorbates.

Four lots of chars have been produced from woods of Acacia auriculaeformis and Acacia mangium, 8-9 and 23-24 years old. The aim of this study is to determine the optimal age of the woods in order to obtain high quality activated carbon. From the comparative analysis of physico-chemical properties of the chars, it has been found that the relative densities increase from 8-9 years old trees to 23-24 years old trees (0.39 to 0.43 for A. auriculaeformis and 0.31 to 0.38 for A. mangium. The ashes rate decreases with the increasing of the age of wood: from 1.075 to 0.990% for A. auriculaeformis, from 1.025 to 0.925% for A. mangium. Otherwise, the rate of volatiles of the chars don't practically change whatever the age and the species (from 23.24 to 23.66% for A. auriculaeformis and from 24.40 to 24.92% for A. mangium). The same tendency is observed with the rate of fixed carbon: from 74.69% and 73.58% for 8-9 years old woods, they are, respectively 74.35% and 73.16%. We can conclude that technical, economic and environmental point of view the activation of chars produced from 8-9 years old woods can be recommended.