The applications of various clay minerals are related to their structural, physical, and chemical characteristics. These properties of the clay minerals dictate their utilization in the industries an...
to the bentonite suspension, up to a volume of 200 mL. 2.3 Activation and modification of ben-tonite clays The acid activation of bentonite clays has been prepared using 5 g of bentonite was placed in a 500 mL beaker, to which 200 mL of sulfuric acid solution of given concentration (5-30 %) was added. The suspension was kept at
Acid activation is a chemical treatment traditionally used on clays, typically bentonites in hydrochloric or sulphuric acid, to obtain partly dissolved materials with enhanced …
The near surface bentonite has undergone extensive calcification, and in some zones it is so heavily altered as to diminish its swelling properties. These low-swelling …
Acid activation was carried out by heating muds prepared from Ca-rich bentonite (CaB), sulfuric acid (H 2 SO 4) and distilled water, yielding various bleaching earths (BEs).The roles of each of the process variables, namely mass fraction of H 2 SO 4 (x) in the dried CaB and pure H 2 SO 4 mixture, heating temperature (T) and contact time (t), in the activation were tested.
The purpose of this study was to apply a factorial 2 3 experimental design to a Serbian bentonite in order to determine the influence of microwave heating on the acid-activation process. The effect of acid activation under microwave irradiation on the textural and structural properties of bentonite was studied as a model reaction.
Nowadays soda activation of bentonite rich in Ca-smectite is a standard industrial practice in manufacturing of drilling muds, binders, litter, adsorbents, barrier clays, etc. Transformation ...
During the acid activation of bentonite, a decrease in the intensity of stretching and bending bands (a characteristic of octahedral sheet for Al-Al-OH) is observed at 1650 cm −1, which reflects the leaching of octahedral cations, such as Al 3+ and Mg 2+, from the bentonite structure, thus indicating the destruction of the octahedral layer.
We aimed to investigate the effectiveness of activated bentonite in OMWW treatment. Batch and column techniques were applied. Crude and treated OMWW samples …
Handbook of Clay Science. P. Komadel, J. Madejová, in Developments in Clay Science, 2013 Abstract. Acid activation is a common chemical modification of clays, usually bentonites, with a hot solution of a mineral acid (typically HCl or H 2 SO 4), and it is used for both scientific and industrial purposes.The aim is to obtain partly dissolved material of increased specific surface …
By applying activation techniques, the reactivity of bentonite can be improved, and its incorporation levels can be maximized. In this study, the influence of mechanical and thermo-mechanical activation of bentonite is investigated on properties of concrete. Bentonite was used for 0%, 10%, 15%, 20%, 25%, 30%, and 35% mass replacements of OPC.
Acid-activation of bentonite was optimised to prepare an effective adsorbent of toluene. The activated bentonite was obtained with a specific surface area of 195 m 2 /g, a pore volume of about 0.46 cm 3 /g and a most frequent pore size of 62. Å.. Compared to the raw bentonite, the adsorption of toluene onto acid-activated bentonite was increased from 66 …
Acid-activation of natural bentonite has been the subject of numerous studies (Bergaya and Lagaly, 2001; Carrado and Komadel, 2009). The acidic attack of bentonite can improve its behaviour by removing impurities and various exchangeable cations from the structure.
Activation of bentonite by acid is an important step for adsorption of some impurities by active clay [6]. This is so-called "activation process". The activation of bentonite is carried out in a continuous stirred tank reactor at low temperatures between 70 and 120 °C in the presence of activation agents, mostly sulfuric acid [7].
The activation of bentonite clay by Na 2 CO 3 can be achieved by treating the clay with Na 2 CO 3 solution thereby incorporating exchangeable Na + ions and increasing the cation exchange capacity, surface area and adsorption capacity of the bentonite clay [11]. On the other hand, thermal treatment of clay is a very common route to increase the ...
2014. Structural modification of clay minerals is necessary to improve their applicability. Bentonite from Nkaliki was treated with different concentrations of sulphuric acid ranging from 0.5 – 5.5mol/l to investigate the effects of acid activation on the structure and properties of the treated samples.
Activation using acid is a proven and reliable technique that causes a controlled, peripheral dissolution of the clay generating active sites. The layered structure of bentonite has an alumina octahedral sheet in between two silica tetrahedral sheets providing an uniform …
The acid/alkaline washing is the common method for the activation of bentonite to remove impurities (e.g., quartz), eliminate natural occurring cations by H + /OH − exchange in acid/alkaline solution, which increase its specific surface area, reactive sites and porosity.
subjected to an activation process (acidic, alkaline, thermal or mixed) [9]. Acid activation is a chemical treatment that is generally carried out with hydrochloric or sulfuric acid. The increase in the adsorption capacity of bentonite depends on the activation conditions (acid concentration and type, temperature, contact time,
Activations of Ethiopian Hadar bentonite clay were modified by using hydrochloric acid. Hydrochloric acid was used to enhance the activated Hadar bentonite clay to be utilized …
The goal of this study is to systematically evaluate the optimum conditions for the sulphuric acid activation of a Turkish bentonite to produce a powder with the maximum bleaching power for soybean oil by analyzing the individual and combined effects of activation variables including mass fraction of H2SO4 (x) per dried CaB and pure H2SO4 ...
In this work, the sodium salt induced activation of bentonite derived adsorbent at low temperature has been attempted. The specific surface area, and total pore volume was …
The sodium salt-assisted low temperature activation of bentonite (BB) was attempted. The unique features of the raw bentonite and BB were characterized with respect to the morphological ...
Thermodynamic analysis illustrated that the adsorption process was feasible and exothermic in nature, while the characterization findings verified the alteration of FTIR bands. Herein, the facile one step acid activation of bentonite derived functionalized adsorbent (AB) for the effective remediation of both ionic and non-ionic secondary pesticides, ametryn and …
The bentonite clay after acid activation was used as a catalyst for diester preparation using succinic acid and ethanol. The conversion of succinic acid was 62% with high yield (73%) of valuable ...
But, when natural bentonite which is Ca- bentonite was activated by Na 2 CO 3 it changes the oxide contents and becomes Na-rich bentonite. For instance, the sodium oxide and calcium oxide present in the natural bentonite before activation were analyzed and the results show the Na 2 O of raw bentonite was lower than AB5 as presented in table 2.
The sodium salt-assisted low temperature activation of bentonite (BB) was attempted. The unique features of the raw bentonite and BB were characterized with respect to the morphological, functional, and textural analysis. The adsorptive behaviour was evaluated by adopting methylene blue () as the model pollutant via batch adsorption experiment.
The activation of bentonite is carried out in a continuous stirred tank reactor at low temperatures between 70 and 120 °C in the presence of activation agents, mostly sulfuric …
Herein, the facile one step acid activation of bentonite derived functionalized adsorbent (AB) for the effective remediation of both ionic and non-ionic secondary pesticides, …
Magnetic MnFe2O4-bentonite was synthesized by chemical co-precipitation method(CCM) and applied as catalyst in heterogeneous activation of persulfate(PS) to oxidize a target pollutant, 2,4-dichlorophenol(2,4-DCP), in aqueous solutions. The surface morphology and structure of MnFe2O4-bentonite were characterized by X-ray diffraction( XRD), scanning …
2.2 Activation of bentonite clay Activation was done based study of Samira & Moussa, 2014; 400 mL of hydrochloric acid (2M HCl) (98%, d = 1.98 g/cm 3 ) solution was added to 50 g of NB sample.
Request PDF | On Feb 14, 2022, J.Kh. Khamroyev and others published MECHANICAL ACTIVATION OF NAVBAHORSK BENTONITE AND ITS TEXTURAL AND ADSORPTION CHARACTERISTICS | Find, read and cite all the ...
The optimum moisture of the bentonite samples for soda activation was found to be 40% in our preliminary activation studies on viscosity, swelling, and filtration loss. In soda activation, soda ash powder was added to the initially moisturized bentonite samples and kneaded till all the bentonite had reacted with soda.
Similarly, bentonite activation is a complex phenomenon that involves the substitution of exchangeable cations, Al 3+, Mg 2+, and Fe 2+ against protons from the octahedral sheet, resulting in the improvement of bleaching effectiveness, greater hydrophobicity and porosity structure, strongly protonated clay mineral surface, increase in specific ...
Acid activation of bentonite clay for recycled automotive oil purification. johanna aguilar. 2020, E3S web of conferences. See full PDF download Download PDF. Related papers. Activation of Kosovo Bentonite with Sulphuric Acid for Recycling of Used Motor Oils.
Jordanian bentonite was activated by hydrochloric acid at room temperature. FTIR, XRD, TGA, and BET surface area analyses of the samples were carried out to examine the structure of bentonite ...
The effects of activation parameters (time and temperature) on its physiochemical properties and its performance for the removal of sodium ions from water were investigated. Bentonite activated for 6 h at 300 °C showed a maximum specific surface area of 81.74 m 2 /g while the raw one showed 57.6 m 2 /g. However, the cation exchange capacity ...
SUMMARY Acid activation of Bentonite for use as a vegetable oil bleaching agent The design of various experiments in order to assess and simulate the effects of the acid activation of an Algerian bentonite on the bleaching capacity of Colza oil is described. Three key parameters of the acidic activation, namely acid concentration, contact time ...