��ϴ��EDTA ���ƺ����������������γɵ�����Ｐ�ӱ���������ϵ�������Ϊ�о�����: ����������ϴ������Ч��ȡ������е�Cd���γɵ��������Ǩ�ƹ��������ܽϺõر�����������������Cd2 +��Cd--EDTA ��Cd--���������������˳��Ϊ: Cd--�����᣾ Cd2 + �� Cd �� EDTA; 3 ����̬���������̾������ӽ�������Ϊ��������15 min ����ɡ������Cd2 + ��Cd �� �������������������Һ��ʼpH �����߶����󣬶�Cd--EDTA ������������pH �������н��͡�

The adsorption behaviors of cadmium and its complexes with two kinds of eluents including EDTA disodium and trisodium citrate on clay were studied�� The results showed that the two kinds of eluents had strong chelating ability for cadmium in topsoil��and the complexes were strongly adsorbed by clay in their transport process�� The sequence of adsorption capacities of clay was: Cd--citrate �� Cd2 + �� Cd--EDTA��and the main sorption mechanism of the three forms were ion-exchange absorption and could be obtained in 15 min�� The adsorption quantity of clay increased to Cd2 + and Cd--citrate and slightly decreased to Cd--EDTA��along with the increasing of initial pH value in solution��