C - Lublin
C - Lublin
C - Lublin
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
The analysis of the specific surface area of the investigated preparations proved<br />
that the addition of humic acids to the minerals caused an increase in their specific<br />
surface area at all pH values both with and without aluminum. Observing the<br />
impact of pH on the specific surface area there was noticed growing tendencies<br />
with decreasing pH value from 7 to 3, which might have been caused by the<br />
transformation of the crystal lattice of the used clay minerals during the elaboration<br />
leading to formation of the synthetic bindings of minerals, humic acids and<br />
aluminum ions. That gradual increase of the specific surface area might also be<br />
related to the formation of amorphic silica of a great area in the processes of acid<br />
mineral destruction [Drees et al.1989]. Therefore, at pH 3, the specific surface area<br />
has the greatest value. The changes in the suspension of the organic-mineral<br />
bindings may cause the destruction of the crystal lattice of clay minerals. Those<br />
processes occur at the presence of hydrogen ions adsorbed exchangeably on the<br />
mineral surface. The attack of protons in the case of montmorillonite takes place on<br />
the face side, while in kaolinite – on the side of mineral plate, which has a great<br />
impact on the specific surface area of the investigated minerals [Motowicka-<br />
Terelak 1979; Milene et al. 1995; Józefaciuk 1995; Józefaciuk 1998].<br />
Generally it can be stated that the degree of reaction of humic acids with<br />
minerals depends most of all on the type of mineral, pH value, and the presence of<br />
aluminum.<br />
REFERENCES<br />
1. Brunauer S., Emmet P.H, Teller E., 1938. Adsorption of gases in multi-molecular<br />
layers. Journal of the American Chemical Society, 60, 309-319.<br />
2. Cygański, A., (1991). Electrical-analytical methods., (in Polish). Wydawnictwo<br />
Naukowo-Techniczne, Warsaw.<br />
3. Drief, A., Nieto, F. And Sanchez-Nevas A. 2001. Experimental Clay-mineral<br />
formation from a subvolcanic rock by interaction with 1M NaOH solution at room<br />
temperature.<br />
4. Józefaciuk, G. (1998). Changes of surface properties of soils and clay minerals in<br />
acidification and alkalization processes. (in Polish). Acta Agrophysica, 15, Monograph.<br />
5. Józefaciuk, G., Hajnos, M., Sokołowska, Z., Renger, M. (1995). Influence of surface<br />
coverage by humic acids on surface free energy and wettability of quartz and kaolin.<br />
Polish Journal of Soil Science, 28 ,30-35.<br />
6. Kalra, Y.P., Maynard, D.G. (1991). Methods manual for forest soil and plant analysis.<br />
Information Report Nor-X-319, Canada, 35-37 pp.<br />
7. Milne, C. J. Kinnburgh, D. G., de Wit,. J.C.M., van Riemsdijk, W. H. & Koopal, L.K.<br />
(1995). Analysis of proton binding by a peat humic acid using a simple electrostatic<br />
model. Geochemica et Cosmochimica Acta, 59, 1101-1112.<br />
96