A distillation column for separating a multicomponent mixture into at least three fractions. The distillation column has at least one separating wall and at least one material exchange element (1) above the at least one separating wall. A device (10) for mixing the steam flows flowing upwards to the left and the right of the at least one separating wall is arranged between the at least one separating wall and the at least one material exchange element (1). The use of the distillation column for purifying isocyanates, in particular for toluene diisocyanate (TDI), is also described.