(646c) Application of Silane-Modified Silica of Different Morphologies Towards the Demulsification of Water in Oil Emulsions

The separation of oil and water poses challenges to several major industries. Industries that deal with water purification and petroleum refining routinely deal with emulsions that are difficult to separate into individual phases. The presence of natural emulsifiers in crude oils and wastewater further complicates the separation of the phases. There is evidence that silica nanoparticles can be potential demulsifiers for emulsions. This study focuses on two parameters, wettability and physical structure, that influence the ability of silica nanoparticles in their separation capacity. Fumed silica and spherical silica of two different geometries were used for the investigation. Wettability alterations were brought about by silane modifications of the silica nanoparticles. Silane chains of various lengths can be impregnated to influence the wettability of a silica particle. Silane chains are inherently hydrophobic by nature while silica is hydrophilic by nature. A longer silane chain impregnation corresponds to a decreased hydrophilicity. Hydrophilicity was measured with respect to the percentage of hydroxyl groups present in the matrix of silica particles. Contact angle measurements were made to verify the hydrophilicity of the produced silica particles. Demulsification experiments were conducted for water in oil (W/O) emulsions using the silica nanoparticles produced. Microscopic analysis was done on the emulsions before and after demulsification experiments to understand the coalescing behaviour of the emulsions in the presence of silica nanoparticles. The presentation will highlight the influence of physical structure and the wettability of demulsifiers on demulsification efficiency.