Abstract:

In order to explore extraction conditions and soil column washing about the citric acid to extract chromium (Cr) from different textures soils, the author took different concentrations, the liquid-solid ratios and the times and washing tests. The results showed that the analytical ability of the citric acid on 3 soils were sand soil>loam>clay. Sandy soil and loam needed big extraction conditions, clay needed smaller extraction conditions. Different concentrations effected extraction, when the concentration of citric acid was 0.05 mol/L, it was good to all the soils. The best liquid-solid ratio and time to soils were clay 1/14, 32 h; sandy soil 1/6, 16 h; loam 1/10, 28 h. The heavy metals contents of clay between 10 and 20 cm layer were bigger than other soil layers. The heavy metals contents of sand soil and loam between 30 and 40 cm layer were bigger than other soil layers. This research provided the technical support for removing chrome from soil.