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The effect of accompanying anions on the adsorbability and extractability of Pb added in soils was studied by using bach equilibria and incubation-extraction mothods. Pb concentration ranged between 0.48-2.41 mM in the adsorption experiment , and Pb added to soil from 2.14 to 19.31mM Pb / kg with an incubation time of 2-16 weeks in the incubation-extraction test in which 1M NH4OAc (pH 7) was taken as an extraction agent, and the Pb compounds used are PbCl2, Pb(NO3)2 and Pb(OAc)2. The values of pH50 for Pb retention and the parameters, b and k values , of Langmuir equation were used to distinguish the difference of adsorbability and extractability of Pb affected by anions, respectively. Judging from the results of either pH50 value or b value, the influences of Cl- and NO3- on the adsorbability and extractability of Pb in soils were similar but quite different from those of OAc . The relative loading capacities of soils to Pb calculated according to the extraction rate showed that the values of Pb(OAc)2
The effect of accompanying anions on the adsorbability and extractability of Pb added in soils was studied by using bach equilibria and incubation-extraction mothods. Pb concentration ranged between 0.48-2.41 mM in the adsorption experiment, and Pb added to soil from 2.14 to 19.31 mM Pb / kg with an incubation time of 2-16 weeks in the incubation-extraction test in which 1M NH4OAc (pH 7) was taken as an extraction agent, and the Pb compounds used are PbCl2, Pb (NO3) 2 and Pb (OAc ) 2. The values of pH50 for Pb retention and the parameters, b and k values, of Langmuir equation were used to distinguish the difference of adsorbability and extractability of Pb affected by anions, respectively. Judging from the results of either results of pH50 value or b value, the influences of Cl- and NO3- on the adsorbability and extractability of Pb in soils were similar but quite different from those of OAc. The relative load capacities of soils to Pb calculated according to the extraction rate showed that the v alues of Pb (OAc) 2