Adsorption of essential oil components of Lavandula angustifolia on sodium modified bentonite from Nador (North-East Morocco)

The analysis of essential oil has basically one technical goal: to achieve the best possible separation performance by using the most effective, available and current technology of chromatography. The present work aimed to study the formulation created by the adsorption of active components of Lavandula angustifolia essential oil on sodium modified bentonite. Essential oils were obtained from dried leaves of L. angustifolia; they were extracted by hydro distillation and were analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography flame ionization detector (GC-FID). The retention indices (RI) were calculated for each detected component. Besides, the characterization of the individual components making up the oils was performed with the use of a mass spectrometry (MS) library. The quantitative analysis was made by GC-FID. The identified components accounted for more than 95% for each essential oil. The results of these studies show that organic contaminant adsorption is dependent, to some degree, on solid-liquid ratio and the competition system of mixture. The adsorption amount of terpenics and the others components could be the results of many factors. The selectivity was affected by the abundance of each component in the crude essential dependent on the particle size fractions; the finer fractions adsorbed higher amounts. The selectivity of adsorption was affected by the polarity of terpenic components.Keywords: Clays, bentonite, essential oil, adsorption, Lavande angustifolia.African Journal of Biotechnology, Vol 13(31) 3413-342

Use of chalky algae in the manufacturing of clayey ceramic membranes: Microstructural and dielectric behavior for electrochemical applications

International audienceNovel ceramic membrane filters were manufactured from kaolino-illitic clays and calcareous algae (up to 20 wt.%) as porogenic agent. The produced membranes were investigated using X-ray diffraction, thermogravimetric analysis, scanning electron microscope, impedance spectroscopy, and Fourier-transform infrared spectroscopy. All of the filtration suitability, electrical properties, and dielectric behavior were assessed and interrelated to the microstructure. It was found that the original clay minerals were involved in the mineralization development while the inclusion of large pores (8–12 μm) was observed at high magnification alongside porosity increase (up to 70%) due to the addition of the bio-based pore-former. Both electric and dielectric measurements revealed that the sintering process was governed by the densification phenomenon and was accompanied with lower activation energy. The order of magnitude of the values taken by electrical impedance was close to average Mega-Ohms suggesting the suitability of the produced ceramic membranes as an electrical insulator for typical electrochemical devices. The tests of filtration have shown that the ceramic membranes produced operate normally in the microfiltration range for a period of 50 min without clogging and at pressures up to 0.12 bar. Conclusively, the developed ceramic membranes could be considered for applications in industrial wastewater treatment and electrochemical media.In addition to this, a perspective has been proposed on the improvement paths or designs for ceramic membrane filters with good performance in wastewater treatment present in some electrochemical environments as well as methods to cope with the challenges regarding the performance of such materials