0086-21-58386256
The initial soil used in this test is Na-bentonite, and its basic physical properties are shown in Table 1.The mold for the electrolysis test was a semi-circular acrylic groove made by ourselves, as shown in Fig. 2: the middle part is an electrolytic cell, and the parts on both sides are solution pools.The Na-bentonite is mixed in a 0.15 mol/L KCl …
Section snippets Molecular models. All MD simulations are carried out with LAMMPS package [54]. Wyoming-type montmorillonite of unit cell formula Na 0.75 (Si 7.75 Al 0.25)(Al 3.5 Mg 0.5)O 20 (OH) 4 is used to model the MMT substrate [25], [45]. The model system consists of two clay sheets, each consists of 20 × 10 × 1 crystallographic …
The bentonite was also identified as Na-bentonite due to the huge Na content present in the clay. The powder X-ray diffraction (PXRD) patterns revealed that both clays are crystalline, together with the Fourier-transform infrared (FTIR) spectrophotometer results; presumably, some impurities of quartz could be present in the clay materials.
Compared to Na +-bentonite, acid-activated bentonite greatly improved the sludge settling characteristics. ... The structure of smectite like montmorillonite is composed of …
An organic compound adsorbent is prepared by modifying acid-activated bentonite with cetyltrimethylammonium bromide (CTAB). The physical and chemical properties of the samples before and after modification are characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) …
The water content of the clay particles also depends on the density of compacted bentonite. As observed by Kozaki et al. (1998), three molecular layers occupy the interlayer space if the dry density of the Kunipia-F clay (99% montmorillonite) stays below 1.3 Mg m −3.For dry densities above 1.6 Mg m −3, a two molecular layer …
When the dominant cation in the bentonite structure is Na +, the clay is defined as Na-bentonite and have the chemical formula of: Na 0.33 Al 1.67 Mg 0.33 (O (OH)) 2 (SiO 2) 4. In addition, bentonite is characterized by having micro-particles with a very small diameter (D 50) usually less than 5 µm; thus, it has a large surface area to …
A commercial MX80 Na-bentonite from Wyoming (USA) and a silty soil collected from Salin-de-Giraud (France) were used in this study. The MX80 Na-bentonite contains 92 % smectite and 3 % quartz . The silty soil is composed of 15.7 % clay minerals including 10.8 % illite, 3.6 % chlorite, 1.3 % kaolinite and 84.3 % non-clay minerals.
Bentonite structure. While sharing a common elementary structure, the various types of bentonite are very different with regard to their chemical composition, as well as to the physical state of their constituents, which account for bentonite different properties and determine its various technological applications. ... (Na +) ions, together ...
Clay minerals such as kaolinite, smectite, chlorite, micas are main components of raw materials of clay and formed in presence of water. A large number of clays used to form the different structure which …
Abstract. Bentonite clay is one of the oldest clays that humankind has been using from ancient times as traditional habits and remedies. In recent years researchers have found many applications of ...
The study aimed to evaluate the adsorption efficiency for removing methylene blue () from synthetic textile dye effluents on natural clay, sodium bentonite. The optimized parameters of the adsorption process were adsorbent dose, shaking speed, temperature, initial concentration of synthetic dye effluent (), contact time, and pH. …
The viscosity of bentonite suspension increased significantly upon the addition of chitosan in the concentration range of 0.5 to 3.0 wt.% forming network structure, which can be attributed to the ...
Ca/Na montmorillonite and natural Wyoming bentonite (MX-80) have been studied experimentally and theoretically. For a clay system in equilibrium with pure water, Monte Carlo simulations predict a large swelling when the clay counterions are monovalent, while in presence of divalent counterions a limited swelling is obtained with an aqueous …
Different from the commonly applied organic bentonite with improved surface hydrophobicity, the PEGs-modified Na-bentonite (MBT) materials were still highly hydrophilic. By varying the Mn molecular weight of the PEGs, the porous structures of the modified Na-BT (MBT) materials were tuned under the synergistic effects of PEG …
For example, Na-bentonite (Wyoming) and MgO mixture was evaluated as an additive in water-borne paints (Karakas et al., 2011). According to this study, flowability and stability of Na-bentonite ...
structure of Mt in the original GMZ Na-bentonite is intact, and the layer spacing value is 1.10 nm, wh ich demonstrates that the layer spacing value of Mt increases after GMZ Na-bentonite is ...
The layered structure of bentonite has an alumina octahedral sheet in between two silica tetrahedral sheets providing an uniform crystalline structure. The space in between the layers is occupied with cations like …
Bentonite is a complex hydrated aluminium silicate with exchangeable cationic components: (Al, Fe, Mg) Si 4 O 10 (OH) 2 (Na,Ca). The most commonly used bentonite …
In the present study, the natural Na-bentonite has been modified by cetyl trimethylammonium bromide (CTAB) to apply to adsorb dyes from aqueous solution. The paper selected cationic dye RhB and anionic dye Acid Red 1 as the target pollutants (the general concentration of 10–600 mg/L for Rhodamine B [38], [39], [40], [41]and 100–2500 …
The formation of rarasaponin-bentonite from intercalation of rarasaponin surfactant with the bentonite are described with the following reaction mechanisms (Kurniawan et al. 2011): the first mechanism is the …
Bentonite is a layer structured clay whose basic structure is ... Na-bentonite, Mg-bentonite and Cu-bentonite are shown in Fig. 2 along with their SAED Patterns. It is noticed
Chemical formula: The chemical formula for montmorillonite, the primary mineral in bentonite, is (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2•nH2O. Overall, the physical and chemical properties of bentonite make it a highly absorbent and reactive material, with the ability to exchange cations and stabilize structures.
X-ray fluorescence spectrum tests. To determine the composition of Na +-bentonite and modified bentonites, X-ray fluorescence spectrometry was used, as shown in Fig. 2.Based on multicore X-ray analysis technology, the instrument integrates wavelength dispersion (WD), energy dispersion (ED), and XRD technology into one instrument, …
The natural bentonite was purified in the laboratory to remove calcite, carbonates, and organic matters by the following protocol: the sample was first repeatedly washed with Milli-Q water and dried after each time. The dried bentonite clay (25 g) was soaked in 400 mL solution containing Na-Ac (0.1 N) and Ac-Ac adjusted to pH ≈ 5.0.
We report the synthesis of Ag/bentonite, ZnO/bentonite and Ag/ZnO/bentonite nanocomposites (NCs) using Hagenia abyssinica plant extract and their antibacterial study. The synthesized NCs were …
Mineralogical and geochemical analysis of sodium bentonites in continental settings: The Uspallata Group (Triassic) of the Cuyana Basin, Mendoza province, …
As the sodium-modified bentonite is obtained by exchanging the interlayer of bentonite with the cations in the permeate, Ca 2+ and Na + remain between the interlayers of the sodium-modified bentonite, thereby limiting the amount of ion exchanges that occur in the solution, which results in a minimal effect on the bentonite structure. …
Bentonite is usually found in its Ca form with lower CEC, which is an essential property for many applications. To improve CEC, Na-activation is a promising method to enrich bentonite with Na cations without any structural damages [].Furthermore, the Na-activation could help to separate the montmorillonite layers from impurities such …