INFLUENCE OF HUMIC ACID COLLOID ON THE SPECIATION OF TRU NUCLIDES

The colloid forming of transuranic nuclides in the loessial groundwater when humic acid exists and the influence of the presence of humic acid on the adsorption of these nuclides on loess are studied. The results show that when humic acid existed in the groundwater,237Np can form pseudocolloid,and the fraction of the colloid increase with the humic acid concentration;the situation for 238Pu and 241Am is the same.The results also indicate that the exist of humic acid weaken the adsorption of these nuclides on loess.