The Effect of Ionic Electrolytes and pH on the Zeta Potential of Fine Coal Particles

Kemal DOYMUŞ

Makale detayları

The Effect of Ionic Electrolytes and pH on the Zeta Potential of Fine Coal Particles

Yazarlar:

Kemal DOYMUŞ

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Chemistry 2007 Vol.31 Issue 6, pp.589-597

Belge Tipi:

Makale

Yayın Tarihi:

5/2007

Belge Dili:

Türkçe

Document ID (Org No.):

2000728587

Sıklık:

İki Aylık

eISSN:

1303-6130

pISSN:

1300-0527

Özet:

 

Many environmental problems are attributed to coal  combustion and utilization, a subject receiving increasing attention  worldwide.  Some of these problems could be minimized or even avoided  if coal cleaning, properly applied, was considered an economical and  effective technique for removing hazardous elements or reducing their  concentrations before combustion.  The coal samples used in this study  were separated into particle sizes of 4, 12, and 40 mesh.  Then these  samples were subjected to sink-float treatment in a ZnCl2 solution of  1.3 density.  The sample used for zeta potential determination was  prepared by grinding both sink and float coal samples down to --100  mesh.  A coal-water suspension of given solid content (wt %) was  prepared at its natural pH of 4.5 (except for the experiments for  determining the effect of suspension pH) with the desired  concentrations of cation and anion electrolytes.  The results of the  experiments to investigate the effect of suspension pH and  concentration of electrolytes on the zeta potential of coal particles  were analyzed using analysis of variance (ANOVA).  According to the  results of this analysis, K+, Ca2+, and NO3- ions on the surface  of coal particles had a minor effect on the observed zeta potentials.   However, Al3+, SO42-, and CO32- ions on the surface of coal  particles had a significant effect on the observed zeta potentials.   In addition, the zeta potential of the coal particles reached a  maximum in 1 \times 10-1 M solutions of both cationic and anionic  electrolytes.  Furthermore, in this study it was observed that the  surface charge of the coal particles decreased at low pH and increased  at high pH.

 

Many environmental problems are attributed to coal  combustion and utilization, a subject receiving increasing attention  worldwide.  Some of these problems could be minimized or even avoided  if coal cleaning, properly applied, was considered an economical and  effective technique for removing hazardous elements or reducing their  concentrations before combustion.  The coal samples used in this study  were separated into particle sizes of 4, 12, and 40 mesh.  Then these  samples were subjected to sink-float treatment in a ZnCl2 solution of  1.3 density.  The sample used for zeta potential determination was  prepared by grinding both sink and float coal samples down to --100  mesh.  A coal-water suspension of given solid content (wt %) was  prepared at its natural pH of 4.5 (except for the experiments for  determining the effect of suspension pH) with the desired  concentrations of cation and anion electrolytes.  The results of the  experiments to investigate the effect of suspension pH and  concentration of electrolytes on the zeta potential of coal particles  were analyzed using analysis of variance (ANOVA).  According to the  results of this analysis, K+, Ca2+, and NO3- ions on the surface  of coal particles had a minor effect on the observed zeta potentials.   However, Al3+, SO42-, and CO32- ions on the surface of coal  particles had a significant effect on the observed zeta potentials.   In addition, the zeta potential of the coal particles reached a  maximum in 1 \times 10-1 M solutions of both cationic and anionic  electrolytes.  Furthermore, in this study it was observed that the  surface charge of the coal particles decreased at low pH and increased  at high pH.

Makale detayları

The Effect of Ionic Electrolytes and pH on the Zeta Potential of Fine Coal Particles

Yazarlar: Kemal DOYMUŞ

Yayıncı: TUBITAK

Dergi: Turkish Journal of Chemistry 2007 Vol.31 Issue 6, pp.589-597

Belge Tipi: Makale

Yayın Tarihi: 5/2007

Belge Dili: Türkçe

Document ID (Org No.): 2000728587

Sıklık: İki Aylık

eISSN: 1303-6130

pISSN: 1300-0527

Sayı

Yazarlar:

Kemal DOYMUŞ

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Chemistry 2007 Vol.31 Issue 6, pp.589-597

Belge Tipi:

Makale

Yayın Tarihi:

5/2007

Belge Dili:

Türkçe

Document ID (Org No.):

2000728587

Sıklık:

İki Aylık

eISSN:

1303-6130

pISSN:

1300-0527