ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Influence of N-alkanes and diacetonyl alcohol on the detachment force of air bubbles detached from a low-rank coal surface

B. Jańczuk, T. Bialopiotrowicz, and W. Wojcik

Department of Physical Chemistry, Faculty of Chemistry, Maria Curie-Sklotlowska University, PL-20-031 Lublin

Abstract: Measurements of the force of detachment of air bubbles from the surface of coal of rank 31.1 and 31.2 precovered with n-alkane in the homologous series from n-hexane to n-hexadecane were carried out in 0 to 10 mass % aqueous solution of diacetonyl alcohol. Using the contact angle values measured earlier in the same system the detachment force was also cal­culated. On the basis of measurements and calculations we stated that the detachment force depend on the thickness of n-alkane film precovering the coal surface, the kind of n-alkane and diacetonyl alcohol concentration. The most profitable conditions for creating a stable connection of coal/n-alkane film—air bubble in diacetonyl alcohol solution were found with a thick n-alkane film at 1 % solution of diacetonyl alcohol. A good agreement between the measured and calculated values of the detachment force for the systems studied was also shown.

Full paper in Portable Document Format: 443a303.pdf

Chemical Papers 44 (3) 303–311 (1990)