Silver speciation in seawater: the importance of sulfide and organic complexes
Silver speciation in seawater: the importance of sulfide and organic complexes
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海水中银的形态：硫化物和有机络合物的重要性
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
E. Jenne
中科院分区：
文献类型：
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作者：
C. Cowan;E. Crecelius;E. Jenne
利用MINTEQ地球化学模型计算了pH值、盐度、硫化物和溶解有机碳（DOC）浓度变化对溶解银形态的影响。天然银有机配合物的分子量平均的条件平衡常数估计从特定的金属有机配合物的平衡常数和有机化合物的浓度，据报道是存在于海水中，总结了主要官能团。计算结果表明，当S（-Ⅱ）浓度大于0.01时，海水中主要的Ag络合物为AgHS/sup 0/。Mu.. g L/sup-1/、AgCl/sup 0/、AgCl/sub 2//sup -/、AgCl/sub 3//sup -/和AgCl/sub 4//sup 0/。如果AgCl/sup 0/复合物是主要的生物可利用的或有毒的化学物质，如已经报道的，则银的毒性将随着S（-II）浓度、pH值的增加和盐度的降低而显著降低。有机络合的银经计算代表总溶解银的<1%，这表明先前归因于DOC络合的银形态变化实际上可能是由于S（-II）或巯基络合物的形成。参考文献42篇，图6幅，表5张。
The effect of variations in pH, salinity, sulfide and dissolved organic carbon (DOC) concentrations on the speciation of dissolved Ag were calculated using the MINTEQ geochemical model. Molecular-weight-averaged conditional equilibrium constants for natural Ag-organic complexes were estimated from the equilibrium constants for specific metal-organic complexes and the concentration of the organic compounds, reported to be present in seawater, summed by principal functional group. These calculations show that the major Ag complexes in seawater are AgHS/sup 0/, for S(-II) concentrations above 0.01 ..mu..g L/sup -1/, AgCl/sup 0/, AgCl/sub 2//sup -/, AgCl/sub 3//sup -/ and AgCl/sub 4//sup 0/. If the AgCl/sup 0/ complex is the primary bioavailable or toxic chemical species as has been reported, the toxicity of silver will decrease significantly with increased S(-II) concentration, pH, and with decreased salinity. Organically complexed silver was calculated to represent <1% of the total dissolved Ag, which suggests that changes in Ag speciation previously attributed to DOC complexation may actually be due to formation of S(-II) or sulfhydral complexes. 42 references, 6 figures, 5 tables.