Conductive liquids charge

If a conducting liquid such as acetone or methanol flows into an ungrounded metal container, the container acquires a charge from the liquid. and a spark may occur between the container and any grounded metal that is nearby, as in the following incidents. 

Principles and Characteristics In electrophoresis the separation of electrically charged particles or molecules in a conductive liquid medium, usually aqueous, is achieved under the influence of a high electric field. This differs from chromatographic separations... 

Conductive liquids in nonconductive containers may cause sparking if the outside of the container is charged by rubbing. 

Gl) have also derived a similar modified equation for the case of a drop of conducting liquid surrounded by a gaseous suspension of both neutral and charged particles, enclosed in a spherical container. 

With the more conductive liquids, the ion concentration becomes so great that ion concentration fluctuations on a statistical basis are likely to be small. However, charging can take place by three other mechanisms (1) mechanical disruption of any double layer of ions that may exist at the surface in times that are short compared with the relaxation time, with a predominance of the surface ions going to the portion of fluid coming from the surface (2) unequal ion mobility with the larger ions unable to return to the bulk of liquid as readily as the smaller and more mobile ones and (3) contaminating materials, such as dust or surfactants at the interfaces serving as ion carriers into one portion or the other of the ruptured liquid. 

Lord Rayleigh On the Equilibrium of Liquid Conducting Masses Charged With Electricity. London, Edinburgh, Dublin Phil. Mag. J. Sci. 1882,14,184-186. 

If a compound, on fusion, forms a conducting liquid phase, the process is not one of simple dissociation because the ions are not completely free, but are either in contact with ions of opposite charge or combined with undissociated molecules. It is to be expected, however, that the number of free ions formed at a given temperature will be greater, the smaller the energy required for the dissociation process, and therefore that fused compounds will be better conductors, the smaller the charge and the greater the radius of the ions. 

Miaoulis, I.N., etal., Theory for electric charging in flow of low conductivity liquids through screens, / Electrostatics, 25, 287-294, 1990. 

Koszman, I., and Gavis, J., Development of charge in low conductivity liquids flowing past surfaces experimental verification and application of the theory developed for tube flow, Chem. Eng. Sci., 1062, 17, 1023-1040, 1962. 

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