Effect of dry density pH on the diffusion behavior of lanthanum in compacted Chinese GMZ bentonite
Abstract
Diffusion experiments in compacted GaoMiaoZi (GMZ) bentonite were performed with La(III) using the in-diffusion method, the effects of dry density pH were emphasized. The apparent diffusion coefficient (D (a)) was obtained at the end of the experiment. D (a) decreases with increasing dry density of 1.3-1.7 Mg m(-3) as well as slightly decreases as pH increases from 3.6 to 8.9. The D (a) range is (2-16) x 10(-12) m(2) s(-1) under the experimental conditions. The distribution coefficients (K (d)) for La(III) in compacted GMZ bentonite are much smaller than those on powdered bentonite obtained from batch experiments.