The extraction of essential oils is generally carried out by two main techniques: azeotropic distillation (hydrodistillation, hydrodiffusion, and steam distillation) and extraction with solvents. However, these traditional methods are a bit expensive, especially since they are extremely energy and solvent consuming. This work consists in studying two methods of extraction of the essential oils of Rosmarinus officinalis L.: microwave assisted hydrodistillation (MAH) and Clevenger hydrodistillation (CH). Several parameters have been studied: the extraction time, the yield, and the chemical composition of the essential oils as well as the efficiency and cost of each procedure. The results obtained revealed that microwave-assisted hydrodistillation makes it possible to minimize the extraction time of the essential oils in comparison with conventional hydrodistillation. Thus, the same yield of essential oils is obtained for 20 minutes only with MAH while it takes 180 minutes with CH. In addition, the quality of the essential oil is improved thanks to a 1.14% increase in oxygenates. In conclusion, the MAH method offers significant advantages over conventional hydrodistillation and can therefore replace it on a pilot and industrial scale.

Providing efficient and environmental friendly ways to recover lignocellulosic waste remains a challenge around the world. In this study, citric acid-catalyzed hydrothermal carbonization (CHTC) was coupled with pyrolysis to convert date seed (Ds) into adsorbent material. In this regard, a central composite design (CCD) using response surface methodology (RSM) was developed to examine the influence of temperature, reaction time, and catalyst dose on the mass yield (Ym(%)) and carbon retention rate (CRR(%)) in the produced hydrochars. The optimized hydrochar (OHC-Ds) was obtained under optimal conditions (200°C, 120 min, 20 mg) and characterized by a Ym(%) and CRR(%) of 59.71% and 75.84%, respectively. Chemical activation by KOH of OHC-Ds followed by pyrolysis at 600°C resulted in an active material (AOHC-Ds) rich in carbon and characterized by a high specific surface area of 1251.5 m2/g, with the dominance of mesopores, as well as an amorphous structure comparable to graphite shown by X-ray diffraction (XRD) analysis. Adsorption experiments of two dyes on AOHC-Ds showed a high maximum adsorption capacity (Qm) of 657.89 mg g−1 for methylene blue (MB) and 384.61 mg g−1 for methyl orange (MO) compared to other conventional adsorbents. This result is due to the low acidity (pHpzc) of the surface of AOHC-Ds, which equals 6.75, and its surface, which is also rich in oxygenated functional groups such as (-OH), (C=O), and (C-O) shown by FTIR analysis. These results suggest that the coupling of CHTC and KOH activation followed by pyrolysis is an encouraging way to prepare an efficient and inexpensive adsorbent to remove dyes in wastewater.

This research aimed to measure the impact of provenance on the yield, chemical profile and antimicrobial activity of Rosmarinus officinalis essential oil (EO) collected from cultivated and wild plants from two different regions in Morocco (Fez and Figuig). The chemical composition analysis was accomplished utilizing the GC-MS techniques. Sixteen compounds were identified in the EO of both samples, dominated by 1,8-cineole (32.18%), camphor (16.20%) and α-pinene (15.40%) in cultivated type. The α-pinene (51.19) presents the majority compound in the rosemary samples collected from the wild populations.The antimicrobial activity was investigated by using the broth dilution methods against yeast, four bacterial strains and two molds. Rosemary aerial part provided EO with the highest yield and comes from Figuig. The GC-MS analysis demonstrated the existence of two chemotypes of oils: α-pinene as well as 1,8-cineole/camphor/α-pinene. Both EOs showed good antimicrobial activity against all microbial strains. The essential oil produced by Fez plants was the most effective against the selected microorganisms having MIC values of 0.315-2.5 mg/L.

Similar to countries with arid and semi-arid climates, Morocco faces problems of degradation of the quality of its environment and more specifically the quality of groundwater. In this work, we approached the physico-chemical characterization of the raw effluents of three industrial units in Fez city, namely the textile industry (U 1 ), the copperware industry (U 2 ), olive oil industry (U 3 ) chosen for their degree of pollution and their environmental impact, the aim of which is to highlight the degree and nature of the pollution generated by these effluents, and their biodegradability during the winter period January to February of 2018, when the waste water treatment plant (WWTP) is malfunctioning. A set of samplings and measurements of different physico-chemical pollution parameters were carried out such as: temperature, pH, electrical conductivity, turbidity, salinity, chlorides, BOD 5 , COD, suspended solids (SS), Ca 2+ , K + , as well as heavy metals. The results show that the U 3 effluent is highly loaded in organic matter with high COD (37600 mg O 2 /L) and BOD 5 (13000 mg O 2 /L), while the U 2 effluent contains very high concentrations of heavy metals (Pb, Ni, Zn, Cu, Cd) 91,8, 71, 55,4, 53, 28 mg/L, respectively. on the other hand, the U 1 effluent is characterized by high SS contents, and concentrations of Ca 2+ , K + exceed Moroccan standards. The COD/BOD 5 ratio shows that U 1 and U 2 effluents are difficult to biodegrade even if their organic loads are low. In the light of these results, it is recommended that these discharges be pre-treated before they are discharged into the liquid sewer system.

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The strategy of doping carbocatalysts with heteroatoms has proven its effectiveness in degrading organic pollutants by persulfate-based advanced oxidation processes. However, research on the effect of doping phosphorus atoms on the degradation performance remains very limited. In this work, a new N, Pdoped carbocatalyst (N,P-HC) is designed by hydrothermal carbonization (HTC) followed by pyrolysis at 700°C using a biowaste (olive pomace) as a carbon source to degrade organic pollutants in the presence of peroxydisulfate (PDS). The experimental results showed that N,P-HC, with its large speci c surface area (871.73 m 2 .g -1 ), high N-pyridine and N-pyrrolic content as well as the existence of P-O-C and O-P-C bonds, provides high degradation performance (98% degradation of Rhodamine B (RhB) in 40 min with a an apparent rate constant (k app ) of 0.055 min -1 and an excellent turnover frequency (TOF) of 0.275 min -1 .The quenching study revealed that singlet oxygen generation ( 1 O 2 ) and direct electron transfer were the main reaction ways for the non-radical pathway in the degradation of RhB. The improved catalytic e ciency can be attributed to the synergistic effect created between N and P atoms in the graphitic structure of the carbocatalyst. On the other hand, a heat treatment at 500°C of the used N,P-HC carbocatalyst allows recovery e ciently their performance. Overall, this study provided a facile and clean method for e ciently synthesizing a high-performance N,P co-doped olive pomace-based carbocatalyst for water depollution in presence of PDS.