Modulating　the　pore　chemistry　and　introducing　ideal　binding　sites　in　MOFs　to　achieve　one-step　purification　of　C2H4　from　ternary　C2H2/C2H4/C2H6　mixture　is　promising　but　challenging.　Herein,　we　report　a　post-synthetic　fluorinated　anions　exchange　strategy　to　access　C2H4　adsorbents　from　a　stable　metal-organic　framework　(MOF)　Fe-BDC-TPT-Cl　of　the　acs　topology　(H2BDC=terephthalic　acid;　TPT=2,4,6-tri(4-pyridyl)-1,3,5-triazine).　Introduction　of　BF4-　and　SiF62-　anions　gave　rise　to　two　new　MOFs,　Fe-BDC-TPT-BF4　and　Fe-BDC-TPT-SiF6　with　retained　topology　but　different　pore　chemistry.　Fe-BDC-TPT-BF4　exhibits　the　highest　C2H2　uptake　of　210.1　cm(3)　g(-1)　at　298　K　and　100　kPa　among　porous　adsorbents　reported　by　now.　Strong　BF4-/SiF62-&　mldr;HC　affinity　enhances　host-guest　interaction,　enabling　high　separation　potential　(Delta　Q)　for　C2H2/C2H4　and　C2H6/C2H4.　Both　static　sorption　isotherms　and　dynamic　breakthrough　experiments　revealed　good　performance　of　Fe-BDC-TPT-BF4　and　Fe-BDC-TPT-SiF6　for　the　C2H2/C2H4/C2H6　separation.　The　productivity　of　C2H4　(purity　＞　99.95　%)　recovered　from　(1/92/7)　C2H2/C2H4/C2H6　over　Fe-BDC-TPT-SiF6　outperforms　that　of　Fe-BDC-TPT-Cl　by　more　than　two　times.　This　work　demonstrates　that　fluorinated　anions　exchange　is　an　efficient　strategy　to　regulate　the　pore　chemistry　of　MOF　adsorbents　for　one-step　purification　of　C2H4.