adsorbée (Q
0
max ) du MB était de 125.64 mg/g (pour l'échantillon IGB04) à 25 °C et pH
7,0.
La diatomite naturelle du site Irghbel s’avère formée dans un milieu marin plus profond,
elle est plus silicifiées et donc plus intéressantes de point de vue exploitation.
Mots clés: Diatomite, diatomées, Caractérisation, Paléoenvironnement, bassin Bas-Chélif
adsorption, bleu de méthylène, modèles d’isotherme.
Abstract
Diatomite is a siliceous sedimentary rock of marine origin. It is considered as a basic raw
material with a wide field of application such as cosmetics, water pollution control,
pharmaceuticals, polymer reinforcement, drink filtration, water purification and
clarification, ecological insecticides, etc….). In order to promote this natural product that
our country contains in large quantities (Bas Chelif Basin), particularly in the region of
Mostaganem (Ouled Djilali and Irghbel) and Sig-Mascara, we have carried out systematic
work of physicochemical characterization and analysis of microfloristic composition. The
objective is to identify and target the areas of interest of this deposit for certain industrial
applications.
For that, various characterization methods and techniques were used such as: light
microscopy (LM), X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF),
Fourier transform InfraRed spectroscopy (FTIR), N 2 adsorption-desorption, and scanning
electron microscopy (SEM) as well as other complementary analysis tests.
The LM observations allow qualitative and quantitative microfloristic exploitation. A
reliable and reproducible methodology for the extraction of diatoms has been developed.
Different diatoms assemblages describing the paleo-environmental conditions in the
sedimentation time were identified. They are all marine and incidentally brackish-marine
species.
The XRD results of the diatomite samples in the investigated areas shows that the principal
minerals were calcite, and amorphous silica (Opal); high content of crystal phases was also
registered. Chemical evaluation showed that the samples were mainly constituted of silica
and calcium carbonates. The FTIR spectra allowed determining the basic characteristic
silica bands regarding of diatomite samples, the main peaks in the infrared spectra reflected
Si-O-H, CaCO 3 , Al-O-Si and Si-O-Si functional groups. While the BET and SEM
investigations revealed that the studied diatomite material having a high porous structure
and was very rich in diatoms.
0
max ) du MB était de 125.64 mg/g (pour l'échantillon IGB04) à 25 °C et pH
7,0.
La diatomite naturelle du site Irghbel s’avère formée dans un milieu marin plus profond,
elle est plus silicifiées et donc plus intéressantes de point de vue exploitation.
Mots clés: Diatomite, diatomées, Caractérisation, Paléoenvironnement, bassin Bas-Chélif
adsorption, bleu de méthylène, modèles d’isotherme.
Abstract
Diatomite is a siliceous sedimentary rock of marine origin. It is considered as a basic raw
material with a wide field of application such as cosmetics, water pollution control,
pharmaceuticals, polymer reinforcement, drink filtration, water purification and
clarification, ecological insecticides, etc….). In order to promote this natural product that
our country contains in large quantities (Bas Chelif Basin), particularly in the region of
Mostaganem (Ouled Djilali and Irghbel) and Sig-Mascara, we have carried out systematic
work of physicochemical characterization and analysis of microfloristic composition. The
objective is to identify and target the areas of interest of this deposit for certain industrial
applications.
For that, various characterization methods and techniques were used such as: light
microscopy (LM), X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF),
Fourier transform InfraRed spectroscopy (FTIR), N 2 adsorption-desorption, and scanning
electron microscopy (SEM) as well as other complementary analysis tests.
The LM observations allow qualitative and quantitative microfloristic exploitation. A
reliable and reproducible methodology for the extraction of diatoms has been developed.
Different diatoms assemblages describing the paleo-environmental conditions in the
sedimentation time were identified. They are all marine and incidentally brackish-marine
species.
The XRD results of the diatomite samples in the investigated areas shows that the principal
minerals were calcite, and amorphous silica (Opal); high content of crystal phases was also
registered. Chemical evaluation showed that the samples were mainly constituted of silica
and calcium carbonates. The FTIR spectra allowed determining the basic characteristic
silica bands regarding of diatomite samples, the main peaks in the infrared spectra reflected
Si-O-H, CaCO 3 , Al-O-Si and Si-O-Si functional groups. While the BET and SEM
investigations revealed that the studied diatomite material having a high porous structure
and was very rich in diatoms.