Abstract This study investigated the soil adsorption characteristics against gaseous mercury. A method for the adsorption tests using gaseous mercury was established, and the distribution coefficients for silica sand, decomposed granite soil, mordenite, and calcium bentonite were evaluated. Glass vials with polytetrafluoroethylene (PTFE) plugs were suitable for the adsorption tests as gaseous mercury did not adsorb onto the glass vials, indicating that the effects of the gaseous mercury adsorbed onto the glass vials are negligible. Although the PTFE plug could not completely seal a vial containing gaseous mercury, the leakage could be corrected using the damping time constant. The soil adsorption tests revealed changes in the gaseous mercury concentrations, which were fitted to the Langmuir nonequilibrium adsorption model. Assuming gaseous mercury did not leak from the vial, numerical simulations were conducted using the fitted parameters of the maximum adsorption amount, adsorption rate, and desorption rate. The evaluated distribution coefficients at equilibrium conditions were 56.3 mL/g for silica sand, 2070 mL/g for decomposed granite soil, 3490 mL/g for mordenite, and 7140 mL/g for calcium bentonite.

中文翻译：

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建立气态汞的土壤吸附测试方法并评价硅砂、分解花岗岩土壤、丝光沸石和钙膨润土的分布系数

摘要 本研究考察了土壤对气态汞的吸附特性。建立了气态汞吸附试验方法，评价了硅砂、分解花岗岩土、丝光沸石和钙膨润土的分布系数。带有聚四氟乙烯 (PTFE) 塞子的玻璃小瓶适用于吸附测试，因为气态汞不会吸附到玻璃小瓶上，这表明吸附在玻璃小瓶上的气态汞的影响可以忽略不计。尽管 PTFE 塞不能完全密封含有气态汞的小瓶，但可以使用阻尼时间常数来纠正泄漏。土壤吸附试验揭示了气态汞浓度的变化，这符合朗缪尔非平衡吸附模型。假设气态汞没有从小瓶中泄漏，使用最大吸附量、吸附速率和解吸速率的拟合参数进行数值模拟。平衡条件下评估的分配系数为硅砂 56.3 mL/g，分解花岗岩土壤 2070 mL/g，丝光沸石 3490 mL/g，钙膨润土 7140 mL/g。