The current study concentrates on chemical kinetics, thermodynamic, and overall mass transfer studies on production of biodiesel from waste cooking sunflower oil in transesterification reaction using bentonite-supported sodium methoxide catalyst. The kinetics and thermodynamics analysis of biodiesel from waste cooking sunflower oil 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 ...
The new thermal treatment optimized and described in this study greatly improved the sodium activation and ions exchange process and improved bentonite properties.
Sodium bentonite expands when wet, absorbing as much as several times its dry mass in water. Because of its excellent colloidal properties ... The modification process by thermal and acid activation is a promising approach for enhancement of the adsorption capacity by 150–250 % for removing synthetic dyes over a wide concentration range ...
Process flow diagram for bentonite processing (EPA, 2005) Slika 1. ... the sodium bentonite is termed as bentonite, and the non- ... technical process known as alkali-activation.
A calcium bentonite clay from Boane region (Mozambique) was subjected to an Na2CO3 activation process. The methylene blue test together with energy-dispersive X-ray spectroscopy (EDX) analysis indicated the successful ion exchange of Ca2+ by Na+ ions since the cation exchange capacity (CEC) increased from 67.5 to 74 meq/100 g …
The heating and stirring are crucial towards enhancing the sodium activation of the bentonite, as well as other rheological properties of the bentonite. ... (1-5 wt. %), the activation process whether it is conducted in a dry state or a wet state may be incomplete and partial (Kaufhold, S., Emmerich, K., Doann, R., Steudel, A., Ufer, K ...
Bentonite production process features ore mining, sodium activation – if required -, drying, and milling. Sodium activation is performed to convert calcium bentonite to sodium bentonite, in which calcium ions are exchanged for sodium carbonate. Through drying, bentonite natural moisture content of about 25-35% is reduced.
The increase in particle size is attributed to two mechanisms, the aggregation that took place at the beginning of the chemical treatment and the later swelling due to the expansion of bentonite platelet because of sodium activation. The swelling process is a kinetically controlled process that depends on time, temperature, and …
There are discussions in the literature about the factors that influence the sodium activation process and about the effect of this process on the properties of the activated bentonite, such as the …
The sodium bentonite mineral "montmorillonite" can be found at different locations throughout the Kingdom. This clay has a mineralogical structure that is suitable …
Example 1 To 500 kg. of bentonite clay, 15.5 kg. of Na CO dissolved in 100 liters of water were introduced. The two latter agents constituted the activator. The solution of the activator was poured on the material which was placed on a belt-type unloading conveyor associated with a multibucket excavator and leading to the steel trucks of a narrow-gauge railway …
In order to improve the quality of Hunyuan inferior Ca-based bentonite (Ca-Bent), semidry process was used to modify Ca-Bent into superior Na-based bentonite (Na-Bent). The factors affecting sodium-modification were investigated. The optimized experimental parameters are obtained as follows: Na2CO3 dosage 4.0%, ageing time …
Following soda activation, the bentonite properties fluctuate and change more or less with time depending on the soda addition. ... (Na 2 CO 3) converts the calcium and/or magnesium bentonites into sodium–calcium forms. In this process which was first proposed by Hofmann and Endell (1936), bentonite moisturized to 35–40% (m/m) is …
In addition, the application of the process to produce other homoionic-forms of bentonite is also worth investigating for the advanced materials research. 4. Conclusions. A weathered bentonite (Japanese acid clay) was altered by a mechanochemical reaction with sodium carbonate without the addition of solvent to give a sodium-type bentonite ...
The sodium activation involved addition of 2–2.5 wt.% Na 2 CO 3 to Ca-rich bentonite in diluted aqueous slurry, followed by washing and drying. Later the process was modified …
Activation process was carried out at different concentrations of sodium carbonate, ranging 3.0–4.5 wt.%. The effects of sodium carbonate concentration, particle size distribution of natural bentonite, activation time and temperature on specific surface area were investigated.
Evaluation of the sodium activation: the activation process was evaluated according to the influence over the properties of swelling and cation exchange capacity (CEC). The swelling index was determined according to Foster's method, which consisted of the slow disposal of 1 g of bentonite sample into a beaker filled with 100 mL of distilled ...
Effect of bentonite activation time and H 2 SO 4 concentration on removal sodium of from water. 3.4. ... small R 2 value in this model is to mean the process is homogenous surface and chemical process better explains sodium adsorption to bentonite. A small value of b (kJ/mol) observed in Temkin isotherm indicated a physical …
The addition of calcium bentonite as catalyst in activating process has been studied in Muhammad and Siddiqua [3].Overall, this study supports the idea that a mixture of bentonite‑magnesium-alkalinization additive is able to improve the strength of silty sand especially after it was heat treated at 60 °C in 24 h.
The sodium removal percentage for bentonite activated for 3 h increases with activation temperature. For bentonite activated for 6 and 12 h, the trend in sodium removal follows the trend observed for the specific surface area shown in Figure 2. Although 6-h time activation showed high specific area in all temperatures as shown in Figure 2, …
Sodium activation, which is an example of chemical modification, is a process developed in the 1930s [5,6]. The discovery was prompted by the observation that only bentonites rich in Na-smectites …
A new process for manufacturing organically compounded bentonite was developed successfully based on the organic intercalation and layered structure of …
In comparison, calcium bentonite has limited swelling, which is why industries prefer to use sodium bentonite. Bentonite Powder Production Process. Bentonite powder production involves several stages that transform raw bentonite rock into refined and packaged bentonite powder. Here's a concise overview of these steps:
Bentonite production process features ore mining, sodium activation – if required -, drying, and milling. Sodium activation is performed to convert calcium bentonite to sodium bentonite, in which calcium ions are …
An upgraded Ca-bentonite was produced using a combined thermochemical treatment in a wet process by adding 4 wt % of soda ash (Na 2 CO 3) while heating and stirring. The new thermal treatment optimized and described in this study greatly improved the sodium activation and ions exchange process and improved …
The sodium removal percentage for bentonite activated for 3 h increases with activation temperature. For bentonite activated for 6 and 12 h, the trend in …
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 ... An optimum removal of sodium by activated bentonite was 19.4% at adsorption conditions of time 180 min, salt concentration of 3486 ppm, solution pH of 10 and adsorbent …
Activation of Bentonite clay using hydrochloric acid (HCl) [15], [16], sulfuric acid (H 2 SO 4) [17], [18] and other acids [19], [20] has been reported. Out of all acids, H 2 SO 4 is preferred mostly as the activation can be performed by mild process conditions and the quality of the end product is better with high specific surface area and ...
Bentonite clay production process features ore mining, sodium activation (if required), drying, milling, classifying, pelleting, etc. Grinding and drying are key steps. Bentonite mining process …
The intercalation of sodium salt into the bentonite surface give rise to the specific surface area and total pore volume from 120.34 to 426.91, ... During the …
Energy changes of bentonite during the heat treatment reaction process. The TG-DSC curves was shown in Fig. 3, TG and DTG curves showed that there were two obvious weight loss phases around 100 ...
Process flow diagram for bentonite processing (EPA, 2005) Slika 1. ... the sodium bentonite is termed as bentonite, and the non- …
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 …
In soda activation, soda ash powder was added to the initially moisturized bentonite samples and kneaded till all the bentonite had reacted with soda. After soda addition and kneading, the activated samples were left to drying/curing under sunlight for a month to complete the activation process (Harvey and Lagaly, 2006).
Bentonite activation was performed with three different concentration of H 2 SO 4 (3, 5, and 10 N), ... acted as a solid acid catalyst due to the hydrogen ions already anchored among its smectite's layers during the activation process. In another word, acid-activated bentonite acted as a proton donor catalyst expediting the esterification ...
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 …
In this paper activation of a typical bentonite in the presence of sodium carbonate was studied by a modified kinetic model. Activation process was carried out at different concentrations of ...
Calcium bentonite may be converted to sodium bentonite (termed sodium beneficiation or sodium activation) to exhibit many of sodium bentonites' properties by an ion exchange process. It is also known as potash bentonite or K-bentonite; potassium bentonite is potassium-rich illitic clay formed from alteration of volcanic ash. ...
A calcium bentonite clay from Boane region (Mozambique) was subjected to an Na2CO3 activation process. The methylene blue test together with energy-dispersive X-ray spectroscopy (EDX) analysis ...