The invention relates to a
recovery method for separating n-
heptane in
tail gas in an
ibuprofen synthesis process by adopting double-
tower extractive distillation. The process comprises the following components: a mixer (M1), an n-
heptane removal
tower (T1), an n-
heptane removal
tower condenser (CL1), an n-heptane
storage tank (C1), an n-heptane removal tower
reboiler (H1), a capture tower (T2), a capture tower condenser (CL2), an
organic matter storage tank (C2), a capture tower
reboiler (H2), a condenser (COL), a
centrifugal pump (P1) and a
centrifugal pump (P2). The method for removing the n-heptane in the industrial
tail gas by the capturing process comprises the following steps: introducing the
tail gas containing the n-heptane into an n-heptane removal tower (T1), introducing a capturing agent into a capturing tower, and capturing the n-heptane in the tower by the capturing agent. And after the n-heptane is completely captured, the obtained
mixed solution enters a capturing tower (T2). Effective separation is carried out in the capture tower (T2),
organic matter mixed liquid is extracted from the tower top, and capture liquid is extracted from the tower bottom. The obtained capturing liquid circularly enters the capturing tower, so that the recycling of the capturing agent is realized. The technical method for capturing the n-heptane in the
ibuprofen synthesis process is economical and environment-friendly.