Experiment for the suction of oil or oil-Elastol mixture laden with or without particles
Experiments demonstrating effective cleaning by sucking off high molecular polymeric liquids were done with oil rather than water-based solvents. These experiments were motivated by the idea that if solid substrates could be cleaned by pulling off thickened liquids, preferably laden with particles, the same could be done with oil slicks. A commercial product Elastol which is effective for cleaning oil slicks is used in just this way. Elastol is a high molecular weight polymer which may be mixed with oil for oil slick removal. Elastol is in liquid and powder form. We did some preliminary experiments to show that this product can be improved by addition of solid particles. A hand held piston with a piston-sucking device is used to demonstrate that the oil can not be removed without additives, that it can be removed when a small amount of elastol is added and that the addition of particles leads to still better cleaning (see the figure below, the movies is at http://www.aem.umn.edu/people/faculty/joseph/cleanup). Panels ii.b and iii.b show the spider-web like structure to cleaning.
i.a i.b ii.a ii.b
i. Movie: suction of oil. ii. Movie: suction of the oil-Elastol mixture.
ii.c iii.a iii.b iii.c
iii. Movie: suction of the oil-Elastol mixture laden with particles.
Three attempts to clean a substrate covered with oil. i. Oil is in the substrate and it cannot be sucked out because the oil breaks. ii. A small amount of Elastol is added to the oil (say 5%) and the oil-Elastol mixture can be pulled out but the bottom of the substrate is slightly soiled with oil. iii. Particles are added to the oil-Elastol mixture. The particles are sub-millimeter and nearly neutrally buoyant. The particles are not special, they are polydisperse and not spheres. The Elastol-oil-particle mixture is pulled out of the beaker; the bottom of the beaker is cleaned.
It is well known that elastol additives are effective in remediating oil slicks. It is true, but not known, that the addition of small particles to the elastol improves the cleaning action of the additives (see http://www.aem.umn.edu/people/faculty/joseph/cleanup/)