Rheology: Open Access
Open Access

Review Article

Yield Stress of Bentonite Dispersions

Petroleum Engineering Program, Texas A&M at Qatar, Qatar

*Corresponding Author:

Vassilios C Kelessidis
Adjunct Professor, Petroleum Engineering Program
Texas A&M at Qatar, Qatar
Tel: +974-33321413
E-mail: vassilios.kelessidis@qatar.tamu.edu

Received date: November 14, 2016; Accepted date: December 08, 2016; Published date: December 15, 2016

Citation: Kelessidis VC (2017) Yield Stress of Bentonite Dispersions. Rheol: open access 1:101.

Copyright: © 2017 Kelessidis VC. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

We review the factors affecting the yield stress of water dispersions of the wonder material, bentonite. Despite the multitude of applications and its wide use in industry, we still do not have adequate models which enable the prediction of the yield stress of these dispersions, which will allow the manufacturing of fluids with made to order properties. Concentration increases the yield stress of these dispersions according to an approximate power of 3.0, but modeling suggests an exponent of 2.0. pH of the suspension gives maxima and minima; however the results are inconclusive regarding their location. The presence of electrolytes decreases the yield stress of these suspensions but a concrete model to predict the yield stress is yet to be found. Polymers increase the yield stress of the suspensions except at initial low concentrations where a decrease is observed due possibly to a liquefying effect. Very recent reported experimental observations show pictures of flexed bentonite particles in band-type structures in co-existence with isolated bentonite platelets. An analysis is presented which attempts to bring some additional light into the development of the yield stress of these bentonite dispersions.

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