The present invention relates to a process for separating a phase (A) comprising at least one ionic liquid from a phase (B), where the phase (A) has a higher viscosity than the phase (B), which comprises the following steps: a) provision of a stream (S1) comprising a dispersion (D1) in which the phase (A) is dispersed in the phase (B), b) introduction of the stream (S1) into a coalescing device (KV), where the inflow rate of the stream (S1) is from 0.05 to 150 kg/(cm2*h) based on the average cross-sectional area of the coalescing device (KV), c) separation of the disperse phase (A) from the phase (B) in the coalescing device (KV), d) discharge of a stream (S2) comprising at least 70% by weight, preferably at least 90% by weight, of phase (A) from the coalescing device (KV) and e) discharge of a stream (S3) comprising at least 70% by weight, preferably at least 90% by weight, of phase (B) from the coalescing device (KV).