Author(s):
1. Ljiljana Tankosić, Rudarski fakultet Prijedor, Republic of Srpska, Bosnia and Herzegovina
2. Svjetlana Sredić, Rudarski fakultet Prijedor, Republic of Srpska, Bosnia and Herzegovina

Abstract:
The knowledge of zeta potential is a very useful indicator of the stability of dispersed systems. This is especially important in many industrial processes, such as e.g. mineral processing, purification of water and many others. This article deals with the investigation of the electrokinetic behavior of goethite, quartz and clay minerals depending on pH and the presence of inorganic dispersants: sodiumhexamethaphosphate (SHMP), sodiumpyrophosphate (SPP) and sodium silicate (NS). All studies are conducted on natural samples, taken from Omarska iron mine (Bosnia and Herzegovina) by measuring the zeta potential. From the experimental results, it was found that the increase of the suspension pH resulted in an increase in the negative charge of all three tested samples. The clay did not show any isoelectric point (IEP). Quartz showed isoelectric points at pH about 2.6 and close to 2 in the absence and presence of sodium silicate in suspensions, respectively. Goethite showed isoelectric points at pH 6.7 and 4.95 in the absence and presence of sodium silicate in suspensions, respectively. An IEP could not be detected when the SHMP and SPP were used and the surface charge is negative from pH 2 to pH 12 in all tested samples. The addition of SHMP provided the highest negative zeta potential, i.e. the most stable dispersion, in all three tested samples.

Key words:
zeta potential, isoelectric point, goethite, quartz, clay, inorganic dispersants

Thematic field:
SYMPOSIUM D - Environmental and sustainable materials

Date of abstract submission:
16.07.2025.

Conference:
Contemporary Materials 2025 - Savremeni Materijali

Applied paper from author