| Adopting the integration method of static and dynamic state, the migration, distribution and material interchange between liquid with solid of chromium, one of the heavy mental, has been researched through experiment and theory method, promulgated Cr (Ⅵ) distributing characteristic and migration rule in soil.The experimental result indicated that the Cr (Ⅵ) adsorption capacity in soil is not obviously , greatly for 1.915μg/g, with the density of Cr (Ⅵ) increasing, the adsorptive capacity of Cr (Ⅵ) increase gradually, but the adsorption rate actually declining, the possible reason is that it associate with the Cr (Ⅵ) be deoxidized by reducer as organic material and so on. pH value, temperature, adsorption time, organic matter etc have a different impact on Cr (Ⅵ) adsorption in soil .Based on the static experiment, the author carried on the dynamic pyramid leaching experiment, the result shows that: Cr (Ⅵ) adsorption in Loess is gradually and evenly until the saturated adsorption, the process of Cr (Ⅵ) purifies adsorption can be divided into 3 stages: Entire adsorption section, part adsorption section and adsorption saturated section. Under the same density condition, the soil is thicker, Cr (Ⅵ) zero value time of drenches fluid is longer, the time of saturated adsorption to be longer also. When Cr adsorbs in soil achieves saturated condition, adding the sewage to drench inputs continuously, the limitation of absorption saturated will be declined.Taking the bentonite as the framework material, The author has prepared several kinds of modified bentonite by different modification method to deal with the Cr(VI) waste water. The results indicate that organic modified bentonite have the good processing effect on Cr(VI) waste water, Its suitable processing technological conditions are: The organic soil content:2g/L, pH value is 5.6 (the waste water initial pH value), the adsorption time is 30min, the adsorption temperature is a room temperature. Under this condition, the Cr (VI) elimination rate of unmodified and roasting modified bentonite is below 35%, that of sour modified bentonite is 65%, but the organic bentonite the Cr(VI) elimination rate can actually achieve about 93% .Integrated experimental data, the author carried on the curve to the adsorption process, has obtained several kind of modified bentonite adsorption isothermals, the result demonstrated that the Cr(VI) adsorption of organic modified bentonite conformed to the Langmuir adsorption uniform temperature type , the sour modified bentonite conformed to the Freundlich uniform temperature type. The Cr (VI) adsorption of organic soil mainly through the ionic exchange and the complex compound precipitation way, the sour modified bentonite adsorbs mainly dependence on the upper edge surface electric of crystal. The adsorption mechanism of acid modified bentonite is mainly the superficial complexing adsorption and the level the ionic exchange adsorption, the Cr(VI) adsorption mechanism of organic soil is mainly the ionic exchange adsorption and the HDTMA- anion complex compound precipitation adsorption, the organic soil processed with the microwave is better than unprocessed soil in Cr(VI) absorption. The elimination rate of Cr (VI) could achieve 93% when 2g/Lof the organic soil content used.Though the research on Cr (VI) migration in liquid-solid system and waste water's procession, it is significant in deal with the pollution of chromium in soil and liquid.
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