| The sorption of trivalent Am(Ⅲ)and Eu(Ⅲ)onto attapulgite and Al2O3 was studied by using the batch techniques.Sorption of Eu(Ⅲ)and Am(Ⅲ)on attapulgite and Al2O3 as a function of pH,ionic strength,Eu(Ⅲ)and Am(Ⅲ)concentrations and organic ligands was studied under ambient condition.The results indicated that sorption of Eu(Ⅲ)and Am(Ⅲ)on attapulgite was strongly affected by pH values and weakly dependent on ionic strength.The sorption of both elements increased steeply with increasing pH from 2.5 to 5.5.Sorption of Eu(Ⅲ)and Am(Ⅲ)was mainly dominated by Surface complexation,although ion exchange also contributed to Eu(Ⅲ)and Am(Ⅲ)sorption.At the relatively low concentration(10-10—10-7mol/L)and relatively low pH(3.4),the sorption isotherms are linear and the average distribution coefficient of both elements is decreased with increasing ionic strength from 0.05 to 0.15 mol/kg KNO3.The experimental resultsof sorption of Am(Ⅲ)and Eu(Ⅲ)onto Al2O3 show that the sorption of botch elements increases steeply with increasing pH from 4.0 to 5.0 and remains Unchanged at relatively low pH(pH＜4.0)or high pH(pH＞5.0)in the presence and absence of phthalate,salicylate,and catechol.While in the presence of fulvic acid,the soption of both elements increases steeply with increasing pH at relatively low pH(pH＜4.0)and it is enhanced obviously relative to that in the presence of other organic ligands.But at relatively high pH(pH＞4.0),the sorption of both elements is reduced obviously.At the relatively low concentration (10-9—10-8mol/L)and relatively low pH(4.5),the sorption isotherms are linear and the average distribution coefficient of both elements is decreased obviously with increasing ionic strength from 0.01 to 0.5 mol/kg KNO3.
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