Author/Editor		Milačič, R; Štupar, J
Title		Fractionation and oxidation of chromium in tannery waste- and sewage sludge-amended soils
Type		članek
Source		Environ Sci Technol
Vol. and No.		Letnik 29, št. 2
Publication year		1995
Volume		str. 506-14
Language		eng
Abstract		Clay, sand and peat soils were mixed with tannery waste so that the final concentrations of total chromium were between 1500 and 2000 micro g g-1 and with sewage sludge where the final concentrations of total chromium ranged out for 2 years under atmospheric conditions. Fractionation of chromium was studied these soils employing a sequential extraction procedure and oxidation of chromium by measurement of chromium(VI) in the water-soluble fractions. The result of fractination studies in the tannery waste-amended soils indicated that the 5 months after the start of the experiment up to 1.1 percent of total added chromium was oxidized in clay, 0.45 percent in sand, and only 0.03 percent in peat soil. The concentration of the water-soluble chromium and chromium(VI) decreased in further continuation of the experiment since chromium was redestributed to more sparingly soluble fractions of soils. The process of chromium oxidation was not observed in sewage sludge-amended soils.
Descriptors		CHROMIUM SOIL POLLUTANTS SPECTROPHOTOMETRY, ATOMIC ABSORPTION FRACTIONATION OXIDATION-REDUCTION