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 …
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1. Introduction. One application of calcium bentonite with a significant market is the decolourization of vegetable, animal and mineral oils. Most of the calcium bentonite used for filtering and decolourizing oils is acid activated (Odom, 1984).Acid treatment with sulphuric or hydrochloric acid removes the calcium cations from the surfaces and edges …
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A bentonite from Kirkouk city region (Iraq) was activated with H 2 SO 4 at various ratios (5, 10, 15, 20 %). Due to ion exchange, the original (Ca, Mg, Na, K)-bentonite was converted to H ...
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A new method of Na-activation of raw bentonite, rich in Ca-montmorillonite, consisting of combined thermal treatment at 200 °C, followed by immediate impregnation with aqueous solution of Na 2 CO 3 of concentration corresponding to 0.5, 1.0, 1.5, or 2.0 cation exchange capacity (CEC) of clay, was investigated. Structural and compositional …
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This study explores, as an alternative to sodium bentonite, the possibility of (Na, Ca)-bentonites to meet the required drilling mud properties. Activation of the bentonites was performed using the most popular (Na 2 CO 3) and also the most controversial additive (MgO) and their blends. Upgrading the (Na, Ca)-bentonites was …
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At a molecular level, insight into this reaction was gained from density functional theory modelling, which showed the different activation energies of the …
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At the third stage, the CaSO4 scaling crystal nucleus is in the colloidal state on the surface of the clay particles, the CaSO4 scaling crystal particles are adsorbed on the surface by excess Ca 2 ...
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Acid activation of bentonite clay for recycled automotive oil purification ... the methods proposed by Aziz et al., (2011). 30 g of clay (previously washed and sieved) was weighed, distilled ...
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Abstract—A study is performed of the effect the means of activation of bentonite-like clays (acidic, alkaline, combined) have on the adsorption characteristics of Fe 3+ ions under static conditions. The mechanism of the ... analysis method is based on the formation of a yellow iron disulfosalicylate complex in alkaline media (pH 9–11.5 ...
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Bentonite is usually a Ca 2+ -bentonite treated with inorganic acids to replace divalent calcium ions with monovalent hydrogen ions and to leach out ferric, ferrous, …
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Effects of Bentonite Activation Methods on Chitosan Loading Capacity Tao Yu1, Chengtun Qu2*, Daidi Fan1, Renjun Xu3 1School of Chemical Engineering, Northwest University, Xi'an 710069, P.R. China
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Iso-conversional methods were used to obtain kinetic-parameters such as the activation energies whereas Coats-Redfern (CR) method was used to find the most probable reaction mechanisms involved on the bentonite pyrolysis. ... (Secretary of Energy)-CONACyT (National Council of Science and Technology in Mexico) …
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This study addresses the urgent need for effective water treatment methods by synthesizing and characterizing activated bentonite clay (ABC) adsorbents to remove methylene blue () from aqueous solutions efficiently. Conventional adsorbents often exhibit limitations in efficiency and regeneration capabilities, necessitating novel …
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Iso-conversional methods were used to obtain kinetic-parameters such as the activation energies whereas Coats-Redfern (CR) method was used to find the most …
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Herein, the facile one step acid activation of bentonite derived functionalized adsorbent (AB) for the effective remediation of both ionic and non-ionic …
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2.2 Methods 2.2.1 Natural bentonite activation Natural bentonite activation was performed by a two-step procedure based on the work done by Toor et al. [28], thermal activation followed by acid activation. Thermal activation was conducted by heating the sample using muffle furnace at 400 °C for 3 hours then cooled and stored
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2.2 Methods 2.2.1 Natural bentonite activation Natural bentonite activation was performed by a two-step procedure based on the work done by Toor et al. [28], thermal activation followed by acid ...
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A new method of Na-activation of raw bentonite, rich in Ca-montmorillonite, consisting of combined thermal treatment at 200 °C, followed by immediate impregnation with aqueous solution of Na2CO3 ...
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Vijayakumar et al. (2009) evaluated acid-activated bentonite as a catalyst in the esterification reaction of the different carboxylic acid with alcohols or p-cresol. Acid activation of bentonite was carried out in concentrated H 2 SO 4 and characterized by FTIR, XRD, SEM, TGA, acid titration and BET surface area. Esterification was carried …
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Acid activation technique was opted for modifying natural bentonite (NB) to enhance the adsorptive removal of CIP from water. The BET surface area analysis …
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In this study, the adsorption of NH 3 gas on a bentonite from Ünye (Turkey) in its natural state and after acid treatments, was investigated experimentally at 298 K and up to 100 kPa. Bentonite was treated with HCl solutions of various concentrations (0.5–2.5 M) at …
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The optimum conditions for activation of FeOOH/bentonite were as follows: filling ratio of grinding medium 30%, "15 mL of D06 balls plus 15 mL of D10 balls" as combination mode of grinding medium ...
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1.. IntroductionBentonite often contains > 80% montmorillonite.Bentonite is used in a wide range of applications including drilling mud, bleaching earth, water and solvent based rheological additives, litter, desiccant clay, and animal feed additive (Lagaly, 2006).Due to high viscosity and swelling and low filtration loss, (Na–Ca) …
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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 …
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Thus, during ultraviolet activation [9] of clays, due to the weakening of bonds in the crystal lattice of minerals, metal ions leave octahedral positions. This helps to increase the sorption activity of clays by 1.3 times. Work [10] presents the results of a combined method of activation of bentonite clays.
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One of the most common chemical modifications of clays, used for both industrial and scientific purposes, is their acid activation. This consists of the treatment of clay with a mineral acid solution, usually HCl or H 2 SO 4.The main task is to obtain partly dissolved material of increased specific surface area, porosity and surface acidity …
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The presence of emerging pollutants such as hazardous chemicals, pharmaceuticals, pesticides, and endocrine-disrupting chemicals in water sources is a serious concern to the environment and human health. Thus, this study focused on exploring the interaction mechanisms between ciprofloxacin (CIP) (antibiotic) and clay (a …
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2.3.4 Physicochemical Methods 35 . 2.3.4.1 Coagulation 35 . 2.3.4.2 Filtration 35 . 2.3.4.3 Ion Exchange 36 . ... 3.2 Muffle furnace used for thermal activation of bentonite 73 3.3 Bentonite modified by TA at 1000C and 5000C for 20 min. 74 3.4 Bentonite modified by AA at 300C for 3h with acid concentration of
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Activation time of bentonite plays an active role in the bleeding reduction. ... This test method permits the evaluation of the swelling properties of a clay mineral. Briefly, after a dried phase, 2 g of bentonite are added to 90 mL of distilled water with step of 0.1 g every 10 min. Once the bentonite adding phase is ended, the water is ...
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