DETERMINATION OF DIFFUSION PARAMETERS BY A COMPUTER CODE (FDP) BASED ON MATHEMATICA 6.0
A computer code named Fitting for Diffusion Parameters (FDP) based on Mathematica 6.0 has been developed for modeling through-and out-diffusion experiments. FDP was used to determine the diffusion coefficients (De) and the rock capacity factors (α) for tritiated water (HTO) and 22Na+and the distribution coefficient (Kd) of 22Na+in Opalinus Clay (OPA).The values for De and α were obtained by fitting the results of experimental data of both transient and steady-state phases to the analytical solution of accumulated activity. The quality of the parameters De and α was tested by using them as input parameters in the equation of flux. Moreover, the diffusion parameters of HTO and 22Na+were determined also by outdiffusion experiments. Under ambient ondition at pH 7.6, the De value of (1.5±0.1)×10-11 m2/s for HTO is lower than that of (1.9 ±1.1)×10-11 m2/s for 22Na+, which could be explained by the electrostatic attraction between the negative surface charge of OPA and the sodium cations. For the non-sorbing species HTO, α was 0.15±0.01. For the weakly sorbing species 22Na+, α was 0.50 ±0.02 and Kd equaled (1.5±0.3)×10-4 m3/kg. The obtained diffusion parameters for HTO and 22Na+in OPA are in good agreement with previous results by Van Loon et al. 1, 2. FDP developed in this study has been used successfully to determine the parameters De and α for the diffusion of 237Np(V) in OPA 3.
Tao Wu Samer Amayri Jakob Drebert Luc R.Van Loon Tobias Reich
Department of Chemistry,Huzhou Teachers College, 313000 Huzhou, China Institue of Nuclear Chemistry,Johannes Gutenberg-Universita Mainz, 55099 Mainz, Germany Institue of Nuclear Chemistry,Johannes Gutenberg-Universitat Mainz, 55099 Mainz, Germany Laboratory for Waste Management, Paul Scherrer Institut, CH-5232 Villigen PSI,Switzerland Institue of Nuclear Chemistry, Johannes Gutenberg-Universitat Mainz, 55099 Mainz, Germany
国际会议
18th International Conference on Nuclear Engineering(第18届国际核能工程大会 ICONE 18)
西安
英文
1-6
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）