Co transport of bentonite colloids and Eu(III) transport in saturated heterogeneous porous media

Natural subsurface environment is a complex heterogeneous system. The key factors affecting the formation of heterogeneous flow and the co-transport behavior of bentonite colloids with Eu(III) under different hydrochemical conditions were investigated in saturated heterogeneous quartz sand column. Quartz sand has a certain filtering effect on Eu(III), the larger sand acts as the preferential flow channel of the heterogeneous media. Media structural configurations and ion strength displayed synergistic effect on the transport and release behaviors of Eu(III) in homogeneous/heterogeneous porous media. Heterogeneous flow in porous media will aggravate the transport risk of bentonite colloid-radionuclide conjugates in the repository environment.