Bentonite found in a drill core of Tsunagi Mine, Niigata, Japan was evaluated by the new method to demonstrate the substantial increase in smectite content from 40% in the …
During the long-term burial of a high-level radioactive waste repository, groundwater can enter the repository through geological fissures and come into contact with bentonite, forming colloidal bentonite particles sized 1–1000 nm in the groundwater [14].These particles exhibit strong mobility and reactivity in solution [15], [16], [17].Some studies have shown that the …
fast method of the active bentonite (montmorillonite) estimation in moulding sands. In order to do that, the spectrophotometric determination method, which is ap-plying triethylenetetramine co. …
The bentonite in this work was sourced from Gaomiaozi region (Inner Mongolia, China), and converted into Na-GMZ bentonite. The purification and conversion procedures for bentonite were described in previous work (Pan et al., 2011).Briefly, bentonite was dispersed in 0.5 M NaCl solution (solid-to-liquid ratio 40 g·L −1) and treated with ultrasonic wave for half an …
In order to predict the diffusion process of bentonite colloids in the fractures of surrounding rocks in the deep geological repository of high-level radioactive waste in Beishan, Gansu, a diffusion model that integrates the self-weight of bentonite colloid particles and hydration force is proposed. ... AGUS S S, SCHANZ T. A method for ...
A modified procedure for bentonite purification and a new method for the quantitative characterization of bentonite using smectite content are reported. Bentonite found in a drill core of Tsunagi Mine, Niigata, Japan was evaluated by the new method to demonstrate the substantial increase in smectite content from 40% in the original bentonite to 75% after purification using a …
for stable bentonite colloidal suspensions. In this work, three ChCl based natural deep eutectic solvent NADES were synthesized by mixing choline chloride as the hydrogen bond acceptor (HBA) with ...
The results demonstrate that when the drop strength of the green ball reaches its optimal level, the five commonly used indicators of bentonite are as follows: water absorption is 545.27% ...
almost all calcium bentonite clay needs to undergo sodium modification.17) However, achieving efficient sodium modi-fication of bentonite has long been a challenging issue for researchers in this field. In addition to exploring various methods and processes for sodium modification, scholars have also sought new insights by investigating the ...
Colloidal particle size distribution and zeta potential has been determined applying the dynamic light scattering (DLS) method. Colloid concentration determination: −A standard series made from MX -80 bentonite applying the DLS measurement count rate. −Al determination ( ICP-MS) BELBaR Helsinki 5. -7.3.2013 . 5 . Formation and stability
The size and shape of colloids released from a natural bentonite into a low-mineralized groundwater are investigated using various colloid characterization methods.
It is obvious that colloid particle size can be reduced by sedimentation or centrifuge methods. Bentonite colloids showed polydiperse and wide particle size ... García-García, S., Wold, S. and Jonsson, M., 2007, Kinetic determination of critical coagulation concentrations for sodium- and calcium-montmorillonite colloids in NaCl and CaCl2 ...
The titration curves of the bentonite colloids showed a typical titration shape of montmorillonite clay, while a common intersection at the point of zero charge (PZC) around 9.5 and a slightly ...
Once bentonite colloids are aggregated, a decrease in ionic strength facilitates disaggregation, but the process is not fully reversible as the initial size of the stable bentonite colloids at low ...
bentonite colloid at dierent conditions and try to provide useful information for the prediction of Cr(VI) behavior in soil-ground water system. Materials and Methods Quartz sand of 1.00–1.18 mm (16–18 mesh) and 0.250–0.425 mm (40–60 mesh) was purchased from Lan- ... taken to be ltered with 0.1 μm membrane for determination of the ...
3 51 efficient sodium modification of bentonite has long been a challenging issue for researchers in this field. 52 In addition to exploring various methods and processes for sodium modification ...
Research on determination of value CEC (Cation Exchange Capacity) Bentonite North Aceh and Bener Meriah with three methods has been studied. The purpose of this study was to determine the value of ...
and bentonite, the dose of bentonite was fixed (10–20–30– 40 mg/L) in each test with a variation of the dose of alumi-num sulfate coagulant from 10 to 120 mg/L. In the section of adding chitosan and bentonite, the chitosan dose was fixed each trial (10–20–40 mg/L) and the bentonite dose was increased (250–500–750 mg/L).
The method was evaluated using four different experimental systems of increasing complexity. Short pulses (equivalent to 0.002 ... DETERMINATION OF COLLOID DEPOSITION RATES 1131 (6) • WASTE DETECTOR (5) COLUMN (2) (4) DEGASSER INJECTION LOOP Figure 1. Schematic drawing of the experimental setup used
In order to improve the defects of fast sedimentation rate and poor mobility of kaolin-supported nano-zero-valent iron (K-nZVI), bentonite colloid with strong suspension and adsorption was selected as the carrier in this study, and the stability and adsorption of bentonite colloid carried with K-nZVI (B-K-nZVI) were studied. The sedimentation tests as well as viscosity tests …
An organoclay/copper-based metal-organic framework (MOF) composite was synthesized using a solvothermal method by growing a Cu-BTC (copper(ii) benzene-1,3,5-tricarboxylate) MOF from a mixture of ...
The objective of the BELBaR Work Package 2 is to understand the mechanisms of colloid and gel layer formation during bentonite erosion. A special focus was set on the characterization of the …
Bentonite is widely regarded as the top choice for buffer barrier material in deep geological repositories due to its excellent swelling properties, enabling it to form a tight seal around waste packages when wet, and its strong sorption capacity for dissolved radionuclides [34], [40].However, as groundwater flows through compacted bentonite blocks, small bentonite …
Furthermore, as mineral colloids such as bentonite eroded from repository backfill have been shown to facilitate transport in the subsurface (Alonso et al., 2006; Missana et al., 2018Missana et al ...
A t /A 0 evolution with time under different K-nZVI dosage: (a) 0 % Bentonite；(b) 1 % Bentonite； (c) 3 % Bentonite； (d) 5 % Bentonite；(e) 7 % Bentonite. The law as shown in Fig. 2 is that the relative absorbance of suspension decreased first and then stabilized with time, which was particularly obvious at low bentonite content, but ...
Stable bentonite colloid dispersions for calibration (in 5 · 10−4 M NaClO4), with a mean size of 250–300 nm, were prepared in the laboratory. The stability of these dispersions was often checked to guarantee the precision of PCS analyses. The PCS's detection limits for bentonite colloid is approximately 1 mg/L.
The structural negative charges deriving from isomorphous substitution in bentonite layers facilitate the association of positively charged radionuclides with bentonite colloids, therefore ...
The Box-Benhnken (BBD) design was employed in the Design Expert software to optimize the parameters of sodium-modified bentonite, determine the optimal value range for the index …
In this study, Gaomiaozi bentonite colloid (GMZC) was extracted using the gravity sedimentation method, and its interaction with U(VI) at neutral pH was studied. ... The mass fraction of the colloids was obtained using the drying method. Three beakers containing 30 mL of GMZC solution were dried in an oven at 80 °C for 4 days ...