May 11 – 16, 2014
Casino Conference Centre
Europe/Prague timezone

Study on sorption and diffusion of Sr in crushed and intact basalt and granite investigated in column method

May 12, 2014, 2:45 PM
15m
Mirror Hall (Casino Conference Centre)

Mirror Hall

Casino Conference Centre

Reitenbergerova 4/95, Mari&#225;nsk&#233; L&#225;zn&#283;, Czech Republic <font color=white>
Verbal Chemistry of Nuclear Fuel Cycle / 1st ASGARD International Workshop Chemistry of Nuclear Fuel Cycle 1

Speaker

Prof. Ming-Chee Wu (Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan)

Description

This study investigates sorption and diffusion of Strontium (Sr) in two potential host rocks (granite from Kinmen Island and basalt from Penghu Island) by using batch and through-diffusion methods in order to establish a reliable safety assessment methodology. These methods were applied to crushed and intact rock samples to investigate the actual geological environment. According to solid-phase analysis, including X-ray diffraction, elemental analysis, auto radiography, and polar microscopy, the sorption component primarily contained iron–magnesium (Fe–Mg) minerals in basalt and granite. Moreover, the distribution coefficient (Kd) of Sr in various concentrations (~10−2–10−7 M) obtained from batch tests indicated a higher sorption capacity in basalt than that in granite because of the 10% Fe–Mg mineral content. The diffusion of Sr both in granite and basalt reach steady state after 100 days and apparent diffusion coefficient (Da) were 3.29×10-11 m2/s (for Sr in crushed granite), 4.17×10-12 m2/s (for Sr in crushed basalt), respectively. However, diffusive result (Da) of Sr in intact rocks was estimated a lower value than those obtained using crushed rocks. According to the diffusive results in crushed and intact rocks, it showed that major retardation of Sr depended on the microporous structure of tested media, such as decreases of constrictivity (δ) and increases of tortuosity(τ). In fact, the solid/liquid (S/L) ratio decreased as is the case when switching from batch to column experiments and the sorption effect on minerals became even more negligible in retardation of radionuclide migration.

Primary author

Prof. Ming-Chee Wu (Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan)

Co-authors

Dr Chuan-Pin LEE (Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan) Ms Chun-Hua Pan (Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan) Dr Lee-Chung Men (Chemistry Divisions, Institute of Nuclear Energy Research, Taoyuan 32546, Taiwan) Dr Shih-Chin Tsai (Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan) Dr Tsuey-Lin Tsai (Chemistry Divisions, Institute of Nuclear Energy Research, Taoyuan 32546, Taiwan)

Presentation materials