This　work　proposed　to　use　the　ionic　liquid　[EMIM][BF4]　as　absorbent　for　the　absorption　of　gaseous　acetic　acid.　The　feasibility　of　this　technology　was　investigated　from　molecular　level　to　industrial　scale.　The　acetic　acid　absorption　experiment　was　carried　out　using　[EMIM][BF4],　and　the　removal　ratio　of　acetic　acid　in　the　gas　product　can　achieve　88.6%　at　20　degrees　C　under　atmospheric　pressure　at　the　laboratory　scale.　Based　on　the　experimental　results,　a　reliable　strict　equilibrium　phase　model　embedding　the　parameters　of　the　UNIFAC　model　was　established.　On　this　basis,　the　conceptual　process　design　and　optimization　of　acetic　acid　removal　by　[EMIM][BF4]　at　an　industrial　scale　was　done,　and　the　most　suitable　design　and　operation　parameters　were　obtained.　For　a　further　step,　the　binding　energy　between　[EMIM][BF4]　and　acetic　acid　was　calculated　to　give　some　insights　into　the　separation　mechanism,　and　the　results　indicate　that　the　interaction　between　acetic　acid　and　IL　is　much　stronger　than　that　between　nitrogen　and　IL.　Moreover,　hydrogen　bond　can　be　formed　between　the　cation-acetic　acid　as　well　as　the　anion-acetic　acid.　(C)　2019,　Institute　of　Process　Engineering,　Chinese　Academy　of　Sciences.　Publishing　services　by　Elsevier　B.V.