The sorption of some inorganic anions to Toyoura fine sand were examined by using single column experiments. Adsorption of Cl
- was weak but SO
42- and PO
43- were adsorbed extremely. The breakthrough curve of SO
42- for Ca
2+ saturated sand was similar to that of cation, though SO
42- was leached with deionized water. This means that the sorption phenomenon is based on not an ion exchange but a chemical reaction on solid phase. The adsorbed ion of PO
43- on a fine sand was not leached with 10
-3N CaCl
2 solution and distilled water. This irreversible phenomenon stems from that the ion pairs of PO
43- as Ca
3(PO
4)
2 or CaHPO
4 are formed in solution and these colloidal particles or precipitates are filtered on fine sand. Iodine in solution consists of two soluble forms, one is nonreactive forms to fine sand, and another is tightly sorbed on the quartz sand. Thus, the behavior of anions is affected by various types of reaction, though it was not based on the ion exchange.
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