论文部分内容阅读
采用连续提取法 ,测定了钴在黄土中的化学形态分布。黄土样采自中辐院野外试验场 ,8个黄土样中分别加入不同量的钴溶液。钴的化学形态分为水溶态钴 (W- Co)、可交换态钴 (EXC- Co)、碳酸盐结合态钴 (CA- Co)、铁 -锰氧化物结合态钴 (Fe,Mn· OX- Co)、有机质结合态钴 (OM- Co)和残渣态钴 (RES-Co)。实验结果表明 ,在钴总含量 [Σ Co,i ]较低 [(1 0～ 40 0 )× 1 0 - 6]时 ,Fe,Mn·OX- Co占优势 ,其α值 (该形态钴含量占钴总含量的份额 )高达 5 0 %～ 80 % ;在钴总含量较高 [(40 0～ 30 0 0 )× 1 0 - 6]时 ,占优势者为CA- Co,其α值为 5 4%～ 77%。引起 CA- Co的α值从约 6 %急剧增大至 5 4%以上的钴总含量为化学形态剧变界值 ([Co]0 ) ,本试验场黄土的 [Co]0为 (40 0～ 5 0 0 )× 1 0 - 6。实验结果说明 ,当 [ΣCo,i]低于 [Co]0时 ,钴进入黄土后将优先生成 Fe,Mn· OX- Co;当 [ΣCo,i]高于 [Co]0时 ,CA- Co是钴在黄土中的主要化学形态。这将使黄土对钴有较强的阻滞能力。
Using continuous extraction method, the chemical distribution of cobalt in loess was determined. Loess sample collected from the field of field hospital Radiation Field, eight loess samples were added different amounts of cobalt solution. The chemical forms of cobalt are divided into water soluble cobalt (W-Co), exchangeable cobalt (EXC-Co), carbonate bound cobalt (CA-Co), iron-manganese oxide bound cobalt OX-Co), organic-matter bound cobalt (OM-Co) and residual-state cobalt (RES-Co). The experimental results show that Fe and Mn · OX-Co are dominant when the total cobalt content [ΣCo, i] is low [(1 0 ~ 40 0) × 10 6], and the α value Accounting for 50% -80% of the total content of cobalt; when the total content of cobalt is high (40 0-30 0 0) × 10 -6, the predominant is CA-Co, and the α value is 5 4% ~ 77%. The total content of cobalt that causes the α value of CA-Co to increase sharply from about 6% to 54% or more is the chemical formula ([Co] 0). The [Co] 5 0 0) × 1 0 - 6. The experimental results show that when [ΣCo, i] is lower than [Co] 0, the formation of Fe and Mn · OX- Is the main chemical form of cobalt in loess. This will make the loess stronger resistance to cobalt.