Electric charging in liquid hydrocarbon filtration: A comparison of theory and experiments

Abstract Experimental data are presented on the charging emfs developed by various types of Millipore filters and a Velcon fuel filter. The filtrate is heptane doped with Shell ASA-3 antistatic additives. In the experiments, the filter pore radius varied by a factor of 30, the filter thickness was varied by a factor of 6, the flow speed by a factor of over 10 3 , and the conductivity by a factor of 2. Good agreement is obtained between the experiments and the theory for charging developed by Huber and Sonin [ J. Colloid Interface Sci. 60, III (1977 )]. As a by-product of the comparison, we obtain estimates for the mobilities of the ions of ASA-3 in heptane: κ + = (0.91 ± 0.21) × 10 −8 m 2 V −1 sec − and κ − = (1.61 ± 0.37) × 10 −8 m 2 V −1 sec −1 .