Distillation is the process by which a liquid is heated to create a vapour and then condensed back into a liquid again. It utilises the boiling point differences to separate substances. 'Sedimentation' is the process of allowing particles in suspension in water to settle out of the suspension under the effect of gravity. 'Filtration' is a process used to separate solids from liquids or gases using a filter medium that allows the fluid to pass through but not the solid. 'Decantation' is a process to separate mixtures by removing a liquid layer that is free of a precipitate, or the solids deposited from a solution.