1. Oil foam

Foam formation is less common in non-aqueous liquids than in aqueous media. However, it is generally accepted that similar physicochemical principles apply, particularly the adsorption of surfactants at the bubble interface. This allows for certain analogies to be drawn with water-based systems. Nevertheless, challenges remain due to the diversity of non-aqueous liquids – such as liquid metals, liquid polymers, crude oils, drilling fluids, lubricants, or vegetable oils –; it is essential to take their highly varied characteristics into account