The hydrophobic surface state of talc as influenced by aluminum substitution in the tetrahedral layer

Atluri, Venkata; Jin, Jiaqi; Shrimali, Kaustubh; Dang, Liem X.; Wang, Xuming

doi:10.1016/j.jcis.2018.10.085

Cited by 29 publications

(13 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The absence of active sites (without hydroxyl groups) on this basal plane surface accounts for its natural hydrophobicity. In previous studies [19,20], the interfacial water structure at talc surfaces was examined using molecular dynamics simulation (MDS). The MDS snapshots of water molecules near the basal plane of the talc It can be seen that the V/F-separation distance plot in Figure 8 exhibits a linear relationship.…”

Section: Discussionmentioning

confidence: 99%

“…Interfacial water density analysis indicates that water molecules are not accommodated at the talc basal plane surface; this water exclusion zone explains the natural hydrophobicity of the talc surface. 2019) [20] with permission from Elsevier.…”

Section: Discussionmentioning

confidence: 99%

“…Molecular dynamics (MD) simulated interfacial water at the talc (001) surface, and corresponding water number density profile revealing the water exclusion zone. Adapted from Atluri et al (2019)[20] with permission from Elsevier.…”

mentioning

confidence: 99%

See 2 more Smart Citations

AFM Slip Length Measurements for Water at Selected Phyllosilicate Surfaces

Zhang

Wang

Jin

et al. 2021

Colloids and Interfaces

Self Cite

View full text Add to dashboard Cite

Most reported slip length measurements have been made at the surfaces of synthetic materials and modified synthetic materials. In contrast, few slip length measurements at the surface of unmodified natural mineral surfaces have been reported. In this regard, flow at the silica face surfaces of the phyllosilicate minerals, talc and mica, was considered. A slip boundary condition was expected at the nonpolar hydrophobic silica surface of talc leading to enhanced flow, and a no-slip boundary condition was expected at the hydrophilic silica surface of mica. Atomic force microscopy (AFM) slip length measurements were made at the talc and mica surfaces. The slip length results for the hydrophobic silica surface of talc were contrasted to the results for the hydrophilic silica surface of mica (no-slip flow). The results are discussed based on molecular dynamics simulations (MDS), as reported in the literature, and AFM images of surface nanobubbles. For nonpolar hydrophobic surfaces (such as talc), it is doubtful that the MDS interfacial water structure and the water exclusion zone (3.2 Å) account for the AFM slip flow with slip lengths as great as 95 nm. Rather, a better explanation for the AFM slip flow condition is based on reduced interfacial viscosity due to the presence of dissolved gas and the accommodation of pancake nanobubbles at the talc surface having a height dimension of magnitude similar to the slip length.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

AFM Slip Length Measurements for Water at Selected Phyllosilicate Surfaces

Zhang

Wang

Jin

et al. 2021

Colloids and Interfaces

Self Cite

View full text Add to dashboard Cite

show abstract

“…These indicated that the adsorption mainly occurred in the dominant basal face of the talc [8,58]. However, talc edge could also play a role in the adsorption of polysaccharides [20,67]. In general, there is a significant relationship between adsorbed amount, the adsorbed morphology, layer thickness, depressant molecular weights, and the subsequent talc wettability.…”

Section: Depressantsmentioning

confidence: 99%

Talc Flotation—An Overview

et al. 2021

View full text Add to dashboard Cite

Talc is a naturally hydrophobic gangue mineral in most sulfide ores. However, talc has vast applications in the cosmetics, paper, and paint industries due to its high chemical stability, and its demand continues to grow. Since flotation is the most effective beneficiation technique for upgrading sulfides, the high hydrophobicity of talc has made its selective separation challenging. This paper explored the different properties of talc and the different factors that affect its flotation separation performance as a proven versatile beneficiation technique. Surface properties, zeta potential measurements, contact angles, and other factors affecting the talc flotation efficiency were discussed in detail. It was observed that the surface face/edge ratio (particle size) has a direct relationship with the level of talc hydrophobicity. Talc surfaces are negatively charged in a wide pH range (pH 2–12). Different depressants have already been studied; however, most of them showed low selectivity. The addition of ions such as Ca2+ could enhance talc depression. Pretreatment methods such as ultrasonic and thermal treatments were reported to decrease the talc floatability. It was demonstrated that the development of new selective depressants or pretreatment options for talc flotation requires attention in future investigations to improve its selective separation.

show abstract

“…It has a naturally hydrophobic character (contact angle ≈ 80º), which is related to their sheet structure and especially to the basal plane areas containing silica tetrahedron bonds. The hydrophilic sites (edge or lateral surface), resulting from the breaking of the sheets during grinding, show the wetting behavior due to the occurrence of -OH groups (essentially silanol) and available for adsorbing hydrophilic (polar) molecules [5]. On the other hand, the hydrophobic sites (basal surface) consists of a tetrahedral siloxane surface with inert -Si-O-Silinks and are responsible for the adsorption of hydrophobic (nonpolar) molecules ( Figure 1).…”

Section: Introductionmentioning

confidence: 99%

Adsorption Behaviour of Ionic and Non-Ionic Surfactants Onto Talc a Naturally Hydrophobic Mineral-a Comparative Study

Dikmen

Ersoy

Dikmen

2020

Eskişehir Technical University Journal of Science and Technology a - Applied Sciences and Engineering

View full text Add to dashboard Cite

In present study, the adsorption behaviour of surfactants which are cationic (hexadecyltrimethylammonium bromide, HTAB), anionic (sodium dodecyl sulphate, SDS) and non-ionic (Triton X100, TX100) onto naturally hydrophobic talc were investigated. In this scope, a series of batch adsorption tests at natural pH were performed to determine adsorption isotherms and zeta potential (ZP) measurements of the ionic and non-ionic surfactants onto talc surfaces were measured using electrophoresis technique. To understand the mechanism of the adsorption process, the adsorption of ionic and non-ionic surfactants was studied as a function equilibrium concentration (mol/L). The amount of maximum adsorption of the surfactants onto talc are ordered as in the following: TX100 (9.0x10 5 mol/m 2)HTAB (8.5x10 5 mol/m 2) > SDS (5.32x10 5 mol/m 2). Even though both the SDS and talc have negative surface charge, SDS can adsorb onto talc. Moreover, a good correlation was obtained between the adsorption isotherms and the zeta potential curves. Considering their adsorption isotherms, the ionic surfactants were showed different adsorption behavior concerning the non-ionic surfactant molecules. The adsorption isotherms of TX-100 and SDS increase rapidly in a narrow concentration range until the plateau region, while such a sharp increase does not appear for HTAB. The maximum adsorption amount of TX-100 and HTAB is greater than SDS. The results indicate that hydrophobic interaction and hydrogen bonding play a decisive role on the adsorption of non-ionic and anionic surfactants onto talc a naturally hydrophobic mineral, whereas electrostatic interaction becomes more important in the adsorption of cationic surfactant.

show abstract

The hydrophobic surface state of talc as influenced by aluminum substitution in the tetrahedral layer

Cited by 29 publications

References 29 publications

AFM Slip Length Measurements for Water at Selected Phyllosilicate Surfaces

AFM Slip Length Measurements for Water at Selected Phyllosilicate Surfaces

Talc Flotation—An Overview

Adsorption Behaviour of Ionic and Non-Ionic Surfactants Onto Talc a Naturally Hydrophobic Mineral-a Comparative Study

Contact Info

Product

Resources

About