Solution Systems for the Displacing of Organic Liquids from Solid Surfaces PDF Download

Author: Marianne K. Bernett
Publisher:
ISBN:
Category :
Languages : en
Pages : 13

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Book Description
Many liquid organic compounds that are effective in surface chemically displacing an adhering layer of a nonaqueous liquid from a solid surface are also effective when used in a solution in an appropriate nonaqueous solvent. Besides reducing the necessary quantity of active solute, the use of a solvent also greatly increases the variety of compounds effective in surface-chemical displacement by including compounds which are either solid (or very viscous) at ordinary temperatures. These principles were established by experiments on displacing hexadecane, propylene carbonate, and Navy Special Fuel Oil from the solid, clean surfaces of SAE 1020 steel, borosilicate glass, and a variety of polymeric organic solids used as insulating materials. Solvents used included common hydrocarbons, fluorinated hydrocarbons, or a combination of either. It was found that highly fluorinated alkanols and low-molecular-weight dimethyl silicones were especially well suited for temporary oil displacement when used in concentrations of only 0.05 to 5.0 wt-%. The duration of liquid displacement could be increased greatly by adding small concentrations (0.1 wt-%) of a compound capable of adsorbing from solution to form an oleophobic film on the solid surface; stearic acid and the higher molecular weight dimethyl silicones are good examples. Permanent oil-displacement from any type of surface was obtained by using concentrations as low as 0.02 wt-% of certain types of progressively fluorinated fatty acids. Applications of the solutions were equally effective whether they were by a dynamic means, such as by spraying or flushing, or by a combination of solution and subsequent ancompetitive adsorption, such as by dipping or immersion. (Author).