1 Bộ môn Thổ nhưỡng – Môi trường Đất, Khoa môi trường, Trường đại học tự nhiên Hà nội.
Từ khóa: anion, phân tán, khoáng sét, đất đồi núi, Sóc Sơn, thí nghiệm, keo lắng, tán sắc
Effect of anions on dispersion of clay fractions separated from soils in hilly area, Soc Son – Ha Noi: sedimentation in test tube and dynamic light scattering study
Nguyen Ngoc Minh
In acidic soils, positively charged edge sites of the clay minerals might favor the formation of edge-to-face structure, the so-called “card house” (van Olphen, 1977), which can help to decrease clay leaching. In this article, the effect of the anions (citrate, oxalate, acetate, , Cl– and ) existing widely in soils on clay dispersion was examined. Card house structure can be formed at pH < 4. However, anions can be adsorbed on positively charged sites of clay edge surface, resulting in a destruction of the card house and accelerating of clay dispersion. The effect of different anions on clay dispersion followed the order oxalate > citrate > axetat > > Cl, . Sedimentation test tube and dynamic light scattering have shown to be helpful tool in determining clay dispersion.