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水样中微量汞的损失和保存法,国内外已有很多报导。稀汞标准液中微量汞的损失,主要是容器器壁的吸附和还原挥发。器壁的吸附机理可能是,器壁存在着对离子吸附的活性点,加入酸作稳定剂,与Hg~(2+)具有相同电荷的H~+占领活性点,即可防止汞的吸附;亦可能是离子的交换作用,玻璃在弱酸性或微碱性溶液中,玻璃表面的负电性硅酸团可使溶液中的阳离子得到交换,碱性玻璃的离子交换能力最强。聚乙稀可能是由于表面电荷双层离子交换作用所致,加入酸亦可防止对重金属的交换。还原挥发是因Hg(Ⅱ)/Hg(Ⅰ)具
There are many reports both at home and abroad about the loss and preservation of trace mercury in water sample. The loss of trace mercury in dilute mercury standard solution is mainly the adsorption and reduction volatilization of the container wall. Adsorption mechanism of the wall may be that there are active sites on the wall of the ion adsorption, adding acid as a stabilizer, and Hg ~ (2 +) has the same charge H ~ + occupancy active point, to prevent mercury adsorption; May also be the exchange of ions, glass in weakly acidic or slightly alkaline solution, the negative surface of the glass surface of the silicate solution can exchange cations, basic glass ion exchange capacity of the strongest. Polyethylene may be due to double-layer ion exchange of surface charge due to acid addition to prevent the exchange of heavy metals. Reduction of volatile due to Hg (Ⅱ) / Hg (Ⅰ) with a