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791.
汞和镉在土壤中的吸附和运移研究进展   总被引:20,自引:2,他引:20  
介绍了国内外近年来对重要的污染元素汞和镉在土壤中吸附和运移方面的研究成果。评价土壤吸附重金属离子多运用Langmuir、Freundlich及Temkin三种等温吸附曲线。影响土壤吸附汞和镉的因素主要有pH值、有机质、氯离子、土壤组分、土壤类型、竞争吸附离子的参与等。汞的活动性较差,其迁移性质缺乏研究;土壤中镉的二价离子在粘土衬层内的迁移过程中,可生成难溶性沉淀物质,阻碍了液体的渗透,因而导致渗透系数比纯水还低。引用参考文献45篇。  相似文献   
792.
炉渣处理含磷废水的实验研究   总被引:9,自引:0,他引:9       下载免费PDF全文
以炉渣作为吸附剂,用静态吸附实验方法研究了炉渣对模拟含磷废水脱磷的一般规律,结果表明,炉渣是一种有效的吸附剂,对废水中的磷有较强的吸附去除性能。影响炉渣除磷的主要因素有吸附时间、炉渣用量、pH值和原水含磷浓度。在含磷浓度2~13mg/L、炉渣用量5g/L、中性、吸附时间为2h的实验条件下,磷的去除率可高达99%以上。  相似文献   
793.
研究了P350在硫酸介质中吸附铼的性能和微色谱柱分离微量铼的条件和选择性,确定了以P350萃淋树脂为固定相,硫酸溶液为流动相萃取色谱分离微量铼的最佳条件,以2mol/L硫酸为上拄液,4mol/L硫酸为淋洗液,水为解析液,使铼与铀(Ⅵ)、钼(Ⅵ)、铁(Ⅲ)、锰(Ⅱ)、铬(Ⅵ)、钛(Ⅳ)等金属离子分离。采用丁基罗丹明B光度法测定铀矿石中微量铼,分析结果符合要求。  相似文献   
794.
电吸附法寻找隐伏矿床在河北后沟金矿试验效果   总被引:7,自引:1,他引:6  
电吸附找矿方法是在室内特别装置中对采集样品通电,并用吸附体吸附试样中电运移元素,通过这些元素所形成的异常来发现隐伏矿体的一种方法。后沟金矿矿体被数米厚黄土覆盖,所做电吸附找矿法试验研究取得较好效果。  相似文献   
795.
Surfacemineralogyisoneofthemodernbranchesofmin-eralogy.Theresearchoftheinterfaceofmineral-liquid,namelythestudyonthereactiono...  相似文献   
796.
蒙脱石对黄曲霉毒素B1的吸附作用   总被引:5,自引:0,他引:5  
试验研究了蒙脱石对黄曲霉毒素B1的等温吸附,以及赖氨酸、酸碱度、温度、离体肠管吸收和透析袋透析对其吸附的影响。结果表明:蒙脱石在pH2.0和pH8.0时对黄曲霉毒索B1的最大吸附量分别为613.5和628.9μg/g;赖氨酸含量为2~4mg/mL时对吸附无影响;酸碱度在pH2.0至pH8.0及温度在20℃至60℃时对吸附无明显影响;蒙脱石可减少离体肠管对黄曲霉毒素B1的吸收率及黄曲霉毒素B1通过透析袋的透析率。鸡小肠对黄曲霉毒素B1存在主动吸收过程。在吸附反应的初始阶段,蒙脱石对黄曲霉毒素B1的吸附符合一级吸附动力学方程,黄曲霉毒素B1半衰期为6.3~7.3min;20min后达到吸附平衡。  相似文献   
797.
Mechanistic roles of soil humus and soil minerals and their contributions to soil sorption of nonionic organic compounds from aqueous and organic solutions are illustrated. Parathion and lindane are used as model solutes on two soils that differ greatly in their humic and mineral contents. In aqueous systems, observed sorptive characteristics suggest that solute partitioning into the soil-humic phase is the primary mechanism of soil uptake. By contrast, data obtained from organic solutions on dehydrated soil partitioning into humic phase and adsorption by soil minerals is influenced by the soil-moisture content and by the solvent medium from which the solute is sorbed.  相似文献   
798.
Abstract: The adsorption of gold on iron(III) and aluminum hydroxides from solutions containing Au(III) complexes has been studied as a function of pH and chloride concentration at 30C. Iron(III) hydroxide was more effective in adsorbing gold from solution than aluminum hydroxide. However, both hydroxides controlled the behavior of Au(III) complex with very similar manner. The most effective gold adsorption occurred in aqueous solution with near neutral pH and low Cl concentration. In this solution condition, Au(III) complexes were mainly dissolved as AuCl2(OH)2- and AuCl(OH)3-, and the surface charge for both hydroxides was positive. In addition, the adsorbed Au(III) complexes were spontaneously reduced to elemental gold in spite of the absence of a specific reducing agent.
The results of this study suggest that adsorption and spontaneous reduction of gold complexes on the surface of hydrous metal oxides with positive charge play an important role in gold precipitation in subsurface environment.  相似文献   
799.
中煤级煤吸附甲烷的物理模拟与数值模拟研究   总被引:3,自引:0,他引:3  
傅雪海  秦勇  权彪  范炳恒  王可新 《地质学报》2008,82(10):1368-1371
基于184个中煤级(镜质组最大反射率Ro,max介于0.65%~2.50%)煤在平衡水条件下的等温吸附实验成果,模拟了中煤级煤的朗格缪尔体积和压力与煤级的关系,建立了不同埋深(温度、压力)条件下不同煤级煤饱和吸附气量量板,探讨了压力和温度对中煤级煤吸附甲烷能力的综合效应,对比分析了中煤级煤吸附特征与低、高煤级煤的差异,提出了中煤级煤吸附气量预测的方法。  相似文献   
800.
Rare earth element (REE) geochemistry and mineralogy have been studied in the weathered crusts derived from the Early Yanshanian (Jurassic) biotite granites of Dabu and Dingnan, as well as in the Indosinian (Permian) muscovite–biotite granite of Aigao in southern Jiangxi province, China, and the weathered crusts and clay sediments on biotite granites in the Sanyo belt, SW Japan, that is, Okayama, Tanakami, and Naegi areas. In all of the weathered crusts, biotite and plagioclase commonly tend to decrease toward the upper part of the profile, whereas kaolinite and residual quartz and K‐feldspar increase. The weathered crusts of the Dingnan granites and some Naegi granites, which are characterized by the enrichment in light REE (LREE) in C horizons, have higher total REE (ΣREE) content than the parent REE‐enriched granites. Weathering of LREE‐bearing apatite and fluorocarbonates in the Dingnan granites and allanite and apatite in some Naegi granites may account for the leaching of LREE at the B horizons. The leached LREE must result in subsequent enrichment of LREE in the C horizons. The enrichment is probably associated with mainly adsorption onto kaolinite and partly formation of possible secondary LREE‐bearing minerals. In Japan it was found that REE mineralization occurs not in the weathered granitic crusts but in reworked clay sediments, especially kaolinite‐rich layers, derived mainly from the weathering materials of REE‐enriched granitic rocks. The clay sediments are more enriched in LREE, which likely adsorbed onto kaolinite. Concentration of heavy REE within almost all the weathered crusts and clay sediments, however, may reflect mainly residual REE‐bearing minerals such as zircon, which originated in the parent granitic rocks. The findings of the present study support the three processes for fractionation of the REE during weathering: (i) selective leaching of rocks containing both stable and unstable REE‐bearing minerals; (ii) adsorption onto clay minerals; and (iii) presence of possible secondary LREE‐bearing minerals.  相似文献   
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