Conclusion
In summary, we have identified an abnormally layered MOF (Zn2(bpy)(btec)) for the highly efficient separation of C2H2 from C2H4 and CO2 mixtures. The interlayer pores cavity can exactly adsorb C2H2 and block C2H4 or the other C1-C3 hydrocarbons, resulting in by far both the highest C2H2/C2H4and C2H2/CO2 uptake ratios (10.31, 3.23) and superior IAST selectivities (107.8, 33.3) among the rigid MOFs. Through size sieving by the appropriate aperture, this MOF achieves efficient separation of C2H2/C2H4(1/99, v/v), C2H2/CO2(50/50, v/v) and simulated steam cracking mixtures, finally obtaining a polymer grade of C2H4 (99.9999%) and a high purity of C2H2 (98%). Furthermore, the synthesis of this material is easily scale-up at an environmentally friendly condition and its structure can be maintained in solutions with a wide range of pH (1~13) as well as in the boiling (373 K) water. These desirable properties of Zn2(bpy)(btec) demonstrated that this new MOF material is a promising adsorbent, which has great potential to be used for the practical C2H2 production process.