Study on the Stability of Bentonite Colloids Under Reducing Conditions
The stability of bentonite colloids under reducing conditions is closely related to the adsorption and migration of radionuclides from the environment in the granite fissures.This paper mainly simulates the effect of ionic strength(Na+,Ca2+)and pH on the stabili-ty of bentonite colloids under reducing conditions,focusing on the effect of SeO32-concen-tration.The results show that the stability of bentonite colloids is better under alkaline con-ditions;when the concentration of SeO32-is higher than 8×10-3 mol/L,the particle size of bentonite colloids changes significantly;compared with the CCC values of cations(Na+,Ca2+)(1×10-2 mol/L,4×10-3 mol/L),the CCC value of SeO32-is small,and the influ-ence on the particle size of the colloids is small;when the concentration of SeO32-is re-duced to 2×10-3 mol/L,the particle size of the bentonite colloid can be restored to that of the colloid at the initial state of the test.