Streaming Potential Measurements on the Binary Mixture Triethylamine-Water Near the Demixing Phase Transition

Abstract

Large density fluctuations developing near the phase transition point of the binary mixture affect physical parameters directly related to the electrokinetic coupling coefficient. Here the first electrokinetic measurements for a porous rock sample are carried out with a critical binary mixture of triethylamine-water, especially around the phase transition point. From the measured streaming potential coefficient, the zeta potential is obtained for the critical composition. The results show that there is no anomaly in the streaming potential coefficient as the temperature approaches the demixing temperature. It is also seen that the streaming potential coefficient and the zeta potential in magnitude decreases with increasing temperature. This observation is opposite to what has been observed in literature. It means that the properties of the electric double layer for the mixtures are different from those for aqueous electrolytes. Additionally, the zeta potential for the critical composition is predicted to fluctuate around the critical point.

Interrelationship of Electric Double Layer Theory and Microfluidic Microbial Fuel Cells: A Review of Theoretical Foundations and Implications for Performance

“…Assuming a cylindrical channel, the solution to Equation (15), based on the appropriate boundary condition, is given as [120,121]…”

“…The phenomena of the streaming potential and streaming current occur due to the charge displacement in the EDL caused by an external driving force displacing the liquid phase tangentially against the solid at the solid-liquid interface [121]. Consequently, the counter-ions in the diffusive part of the EDL are carried downstream in response to a pressure gradient.…”

Department of Electronics, Faculty of Information Science and Electronics Engineering, Kyushu University

“…a) uematsu@phys.kyutech.ac.jp When the solvent is altered by organic solvents or their aqueous mixture 18 , additional effects on the doublelayer capacitance are necessary to consider such as ionic association 19 , preferential solvation of ions 20 , preferential adsorption of solvents to the interface 21 , and phase separation in bulk phase 22,23 . Thus, the structure of double layers in organic solvents 1,24,25 and their aqueous mixtures 20,21,[26][27][28][29][30] are different from that of aqueous ones, and the theoretical description of it is still insufficient. Nevertheless, electric double layers of organic solvents and their aqueous mixtures are significantly important because various chemical and electrochemical products use organic solvents such as detergent, paint, ink, and batteries.…”

Ubiquitous Preferential Water Adsorption to Electrodes in Water/1-Propanol Mixtures Detected by Electrochemical Impedance Spectroscopy

“…When the solvent is altered by organic solvents or their aqueous mixture, additional effects on the double-layer capacitance are necessary to consider such as ionic association, preferential solvation of ions, preferential adsorption of solvents to the interface, and phase separation in bulk phase. , Thus, the structure of double layers in organic solvents ,, and their aqueous mixtures ,,− are different from that of aqueous ones, and the theoretical description of it is still insufficient. Nevertheless, electric double layers of organic solvents and their aqueous mixtures are significantly important because various chemical and electrochemical products use organic solvents, such as detergent, paint, ink, and batteries.…”