Knowledge Resource Center for Ecological Environment in Arid Area
| DOI | 10.2172/5980032 |
| 报告编号 | NUREG/CR-5464 |
| 来源ID | OSTI_ID: 5980032 |
| Anion retention in soil: Possible application to reduce migration of buried technetium and iodine | |
| Gu, B.; Schulz, R.K. (California Univ., Berkeley, CA (United States). Dept. of Soil Science) | |
| 英文摘要 | This report summarizes a literature review of our present knowledge of the anion exchange properties of a number of soils and minerals, which may potentially be used as anion exchangers to retard migration of such anions as iodide (I{sup {minus}}), iodate (IO{sub 3}{sup {minus}}) and pertechnetate (TcO{sub 4}{sup {minus}}) away from disposal site. The amorphous clays allophane and imogolite, are found to be among the most important soil components capable of developing appreciable amounts of positive charge for anion exchange even at about neutral pH. Decreases in the SiO{sub 2}/Al{sub 2}O{sub 3} ratio and soil pH result in an increase in soil AEC. Allophane and imogolite rich soils have an AEC ranging from 1 to 18 meq/100g at pH about 6. Highly weathered soils dominated by Fe and Al oxides and kaolinite may develop a significant amount of AEC as soil pH falls. The retention of iodine (I) and technetium ({Tc}), by soils is associated with both soil organic matter, and Fe and Al oxides, whereas sorption on layer silicate minerals in negligible. Fe and Al oxides become more important in the retention of anionic I{sup {minus}}, IO{sub 3}{sup {minus}}, and TcO{sub 4}{sup {minus}} as pH falls, since more positive charge is developed on the oxide surfaces. Although few studies, if any, have been conducted on I and {Tc} sorption by soil allophane and imogolite, it is estimated that a surface plough soil (2 million pounds soil per acre) with 5 meq/100g AEC, as is commonly found in andisols, shall retain approximately 5900 kg I and 4500 kg {Tc}. It is conceivable that an anion exchanger such as an andisol could be used to modify the near field environment of a radioactive waste disposal facility. This whole disposal system would then offer similar migration resistance to anions as is normally afforded to cations by usual and normal soils. 93 refs., 10 figs., 7 tabs. |
| 出版年 | 1991 |
| 报告类型 | Technical Report |
| 语种 | 英语 |
| 国家 | 美国 |
| 来源学科分类 | 54 ENVIRONMENTAL SCIENCES ; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY ; CLAYS ; CHEMICAL COMPOSITION ; SORPTIVE PROPERTIES ; LOW-LEVEL RADIOACTIVE WASTES ; UNDERGROUND DISPOSAL ; RADIONUCLIDE MIGRATION ; MITIGATION ; SOILS ; WEATHERING ; ALUMINIUM OXIDES ; ELECTROLYTES ; GROUND WATER ; IODINE ; ION EXCHANGE ; IRON OXIDES ; MICROSTRUCTURE ; PH VALUE ; REACTION KINETICS ; SEPARATION PROCESSES ; SILICON OXIDES ; SUBSURFACE ENVIRONMENTS ; TECHNETIUM ; VALENCE ; ALUMINIUM COMPOUNDS ; CHALCOGENIDES ; CRYSTAL STRUCTURE ; ELEMENTS ; ENVIRONMENTAL TRANSPORT ; HALOGENS ; HYDROGEN COMPOUNDS ; IRON COMPOUNDS ; KINETICS ; MANAGEMENT ; MASS TRANSFER ; MATERIALS ; METALS ; NONMETALS ; OXIDES ; OXYGEN COMPOUNDS ; RADIOACTIVE MATERIALS ; RADIOACTIVE WASTES ; SILICON COMPOUNDS ; SURFACE PROPERTIES ; TRANSITION ELEMENT COMPOUNDS ; TRANSITION ELEMENTS ; WASTE DISPOSAL ; WASTE MANAGEMENT ; WASTES ; WATER 540230* -- Environment, Terrestrial-- Radioactive Materials Monitoring & Transport-- (1990-) ; 400105 -- Separation Procedures |
| URL | http://www.osti.gov/scitech/servlets/purl/5980032 |
| 资源类型 | 科技报告 |
| 条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/264563 |
| 推荐引用方式 GB/T 7714 | Gu, B.,Schulz, R.K. . Anion retention in soil: Possible application to reduce migration of buried technetium and iodine,1991. |
| 条目包含的文件 | 条目无相关文件。 | |||||
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
