Influence of surface conductivity on the apparent zeta potential of calcite
Influence of surface conductivity on the apparent zeta potential of calcite
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DOI：
10.1016/j.jcis.2016.01.075
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发表时间：
2016-04-15
影响因子：
9.9
通讯作者：
Chiaberge, Christophe
中科院分区：
文献类型：
--
作者：
Li, Shuai;Leroy, Philippe;Chiaberge, Christophe
Zeta电位是描述带电多孔介质表面电性质的一个特别重要的物理化学参数。然而，方解石的zeta电位仍然知之甚少，因为难以解释流动电位实验。Helmholtz-Smoluchowski（HS）方程被广泛用于从这些实验估计表观zeta电位。然而，该方程忽略了表面电导率对流动电位的影响。我们提出了流动电位和电导率测量方解石粉末与NaCl水溶液电解质接触。我们的流动电位模型校正方解石的表观zeta电位占表面电导率和流动制度的影响。我们发现，HS方程严重低估了方解石的zeta电位，特别是当电解质被稀释（离子强度
Zeta potential is a physicochemical parameter of particular importance in describing the surface electrical properties of charged porous media. However, the zeta potential of calcite is still poorly known because of the difficulty to interpret streaming potential experiments. The Helmholtz-Smoluchowski (HS) equation is widely used to estimate the apparent zeta potential from these experiments. However, this equation neglects the influence of surface conductivity on streaming potential. We present streaming potential and electrical conductivity measurements on a calcite powder in contact with an aqueous NaCI electrolyte. Our streaming potential model corrects the apparent zeta potential of calcite by accounting for the influence of surface conductivity and flow regime. We show that the HS equation seriously underestimates the zeta potential of calcite, particularly when the electrolyte is diluted (ionic strength