Hydrophobization of diatomaceous earth used to remove oil pollutants

Contamination of the natural environment with petroleum pollution is still a frequent and particu-larly dangerous phenomenon, thus there is a need to remove these pollutants. Various types of mineral sorbents (silicate minerals, zeolites, perlite, diatomite, clay rocks) are highly valued in remediation processes due to their affordable, big selectivity and high efficiency. However, many sorbents are not resistant to moisture, which limits their use. The hydrophobization process improves the effectiveness of sorbents used in a humid environment. The DAMSORB produced by IM-POl was hydrophobized with a methanolic stearic acid solution. The use of cheap stearic acid as a modifier is economically advantageous. The evaluation of the hydrophobic properties of the modified material was performed on the basis of the results obtained from the tests: water absorption, floating on the water surface and the contact angles were determined. Tests of the sorption of petroleum-derived compounds were performed on the basis of three procedures: in accordance with the technical sheet of the leading pro-ducer of hydrophobic sorption materials in Poland, the Westighouse's method in the oil layer and the Westighouse's method on a flat surface. The modified sorbent floats on the surface of the water very well. The average value of the contact angle for the modified sample is 104 degrees. Material is super hydrophobic. In the water environment, the hydrophobized samples have a higher absorption capac-ity in relation to oil contaminations compared to the raw material. Features of the modified sorbent, such as good buoyancy on the water surface, low affinity to water and better absorption of oil from the solution, make it possible to use the material to remove petroleum contamination from water and highly moist surfaces.