中文摘要：

为方便准确地表征大颗粒包被物的带电特征，采用自制的流动电位测定装置测定了包铁石英砂的流动电位，并计算获得其电位。结果表明，该装置能够准确测定包铁石英砂在不同液压差（△JP）的流动电位（AE），二者具有极好的直线相关性，因此能保证由△P与AE拟合得到的流动电位系数（c）的准确性。由c计算得到包铁石英砂的ζ电位能够很好地表征其表面电化学特征。在同一种电解质溶液中，包被物ζ电位的绝对值随着包被度的增加而减小。低离子强度下双电层厚度占毛管孔径的比例较大，因此采用流动电位测定包被物ζ电位时必须考虑表面电导的影响。随着离子强度的增加，包铁石英砂的表面双电层受到压缩而造成ζ电位的绝对值减小。采用流动电位法测得包铁石英砂的等电点为4，6。当溶液pH高于等电点时，包被物的ζ电位为负值，且随着pH升高，其ζ电位向负值方向位移。当溶液pH低于等电点时，包被物的ζ电位为正值，且其数值随着pH降低而增加。流动电位法测得的石英砂的ζ电位与传统电泳法测得的石英胶体的ζ电位之间呈极显著的正相关关系，说明流动电位法测定的ζ电位结果可靠。

英文摘要：

Abstract To easily and accurately characterize electrochemical properties of large particles,a homemade streaming potential device was used to measure streaming potential of Fe hydroxide-coated quartz for calculation of its ζ poten- tial. Results show that this device is capable of determining streaming potential （AE） accurately regardless of hydraulic differential （AP）. Between the two exists an excellent linear relationship,which guarantees the accuracy of streaming po-tential coefficient （C） obtained through fitting AE with AP. Hence,the ζ potential of Fe hydroxide-coated quartz figured out from C is good enough to characterize the surface electrochemical characteristics of the Fe hydroxide-coated quartz. In the same electrolyte solution,absolute value of the ζ potential of Fe hydroxide-coated quartz decreases with the increase in coating degree. When ionic strength is low, the electric double layer on Fe hydroxide-coated quartz is quite thick,occupying a large proportion of a capillary pore,thus making it necessary to take into account the effect of surface electric conduction in measuring ~ potential of coated particles based on streaming potential. The electric double layer on Fe hydroxide-coated quartz is compressed with increasing ionic strength of the electrolyte solution,thus causing the absolute value of ζ potential to decline. The isoelectric point of Fe hydroxide-coated quartz measured with the streaming potential method was 4.6. When the electrolyte solution pH went above the isoelectric point,ζ potential of Fe hydroxide-coated quartz was nega- tive and turned more negative with rising pH. However,when the solution pH fell below the isoelectric point,the ζ potential turned positive and increased with declining pH. A significantly positive relationship between the ζ potential of quartz worked out from streaming potential and the ζ potential of quartz colloids measured with the electrophoresis method was ob- served,suggesting that the streaming potential method for measuring ζ pot