Green chemistry for treatment of liquid discharges from a dyeing industry: bio coagulation and flocculation

Textile industry is among the highly polluting industries in water effluent. It consumes large quantities of water and chemicals compounds. These releases can have varying characteristics regarding their volumes and pollutants concentrations. Therefore, adverse effects can be observed as consequence on environment and biodiversity. According to the environmental protection regulations in Morocco, the treatment of this water before discharge is compulsorily to avoid pollution of surface and ground water. The aim of our study is the treatment of these effluents by a physicochemical process using coagulation / flocculation.  Two coagulants of different type and purity are used. The first one “aluminum sulfate” is a pure coagulants used on industrial scale. The second “alum stone” is excerpt from the nature of Moroccan desert. Beside, two flocculants are compared, a natural extract from cactus and a polymer synthesized (polyacrylamide). The comparative study between a pure coagulant and a biocoagulant, with the two flocculants, showed a very good absorbency rate of reduction (ABS), turbidity (T), chemical oxygen demand (DCO), dry matter (DM) and chemical elements (sodium, lithium, nitrogen, phosphorus, boron, and silicon). By the jar test treatment process, the optimal dose of coagulants and flocculants to use in the neutral pH treatment was identified. The optimal dose used gives 85% of abatement efficiency absorbance, 90 % for turbidity and 80% for the chemical oxygen demand. Moreover, the dry matter content is over 25% and over 90% for some chemical elements

Thermal non-destructive characterization of rail networks by using Infrared Thermography and FEM simulation

Because of the repeated passage of trains, anomalies are created inside the rails in the form of cracks of different shapes and position. These are due essentially to the wheel – rail contact. They present a hazard causing at the final stage rail failure, train derailment and accidents. Detecting track anomalies has become a major issue for the entire rail industry around the world. This paper focuses on the degradation of rails in urban railways in terms of cracks. The purpose is to develop an approach to detect and predict rail breaks, which will optimize maintenance task. Infrared thermography was used in order to characterise the effect of a defect on the acquired thermogram. Different defects were considered by varying their size, depth and inclination angle with respect to the rail surface

Valorisation of cellulosic waste basic cactus to prepare activated carbon

The cellulosic waste is the most abundant material in the earth. It is considered as a renewable polymer of wood cell walls and plant cells. It is used in different fields mainly as sustainable potential precursors and it is useful for the preparing activated carbon.The purpose of this study is the valorisation and production of activated carbon from cellulose waste, old cladodes of Ficus indica cactus optunia, and the residue of prickly pear seeds after oil extraction. Preparation and characterization of activated carbon (AC) from the two wastes by chemical treatment, phosphoric acid H3PO4 at a temperature of 450 °C has shown a very good adsorption of methylene blue and iodine. This treatment illustrated an important surface area of 820 m2/g for waste seeds and more than 470 m2/g for waste cactus cladodes. Analysis by infrared and pH point of zero charge showed a basic character for both carbons active developed. Keywords: Cactus, Activated carbon, Fig tree barbarism, Chemical activatio

Impact and Optimization of the Conditions of Extraction of Phenolic Compounds and Antioxidant Activity of Olive Leaves (<i>Moroccan picholine</i>) Using Response Surface Methodology

The Moroccan picholine tree’s leaves contain phenolic compounds that benefit human health. However, the amount and type of these compounds can vary based on factors such as the extraction method and conditions. This study aimed to improve phenolic compounds’ extraction while minimising harmful chemicals’ use. It has been found that using ethanol as a solvent with ultrasonic extraction is the most effective and environmentally friendly technique. Several parameters, such as the extraction time, solid/solvent ratio, and ethanol concentration as independent variables, were evaluated using a surface response method (RSM) based on the Box–Behnken design (BBD) to optimize the extraction conditions. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also examined using the appropriate statistical methods. In optimal conditions, the ultrasonic time, the ratio (solvent/solid) and the concentration (ethanol/water), the content of total polyphenols (TPC), total flavonoids (TFC), and antioxidant activity (by DPPH, ABTS, FRAP) were, respectively, 74.45 ± 1.22 mg EAG/g DM, 17.08 ± 1.85 mg EC/g DM, 83.45 ± 0.89% 82.85 ± 1.52%, and 85.01 ± 2.35%. The identification of phenolic compounds by chromatography coupled with mass spectrum (HPLC-MS) under optimal conditions with two successive extractions showed the presence of hydroxytyrosol, catechin, caffeic acid, vanillin, naringin, oleuropein, quercetin, and kaempferol at high concentrations

Energetic Bio-Activation of Some Organic Molecules and Their Antioxidant Activity in the Pulp of the Moroccan Argan Tree <i>«Argania spinosa</i> L.<i>»</i>

Argania spinosa L. Skeels is an emblematic tree in Morocco, known worldwide for its medicinal and nutritional value. Its fruits contain kernels used to prepare an edible oil, the leaves are used to feed livestock, and its wood is used as fuel. If the oil acquires high importance, the other components of the fruit of the argan are undervalued. Our objective is to invest the waste of the argan industry. Particularly, our study aimed to assess the effect of thermal activation of argan pulp on its therapeutic value, its phenolic profile and its functional and physicochemical properties. After heat treatment, the HPLC analysis for the average total phenolic content varied from 2% to 37%, depending on temperature. The antioxidant activity was increased with heat treatment. Higher values of antioxidant activity, polyphenol and pigment content were recorded at 70 °C. Functional properties analysis indicated that water solubility index and water absorption capacity were significantly affected by heat stress. Physicochemical analysis showed that moisture content, titratable acidity and soluble solids were affected