Rapid synthesis of nanoscale double metal cyanide catalysts by ball milling for the cycloaddition of CO2 and propylene oxide

• Effective and efficient synthesis of nanoscale DMC catalyst via ball milling within minutes.
• Simultaneous incorporation of CTAB into DMC exhibits much smaller particle sizes.
• The particle size achieved nanoscale.
• The DMC catalysts were effective for the cycloaddition of CO2 and propylene oxide.
• The cyclic carbonate has high selectivity.

Ball milling as a green and rapid synthetic technique has shown potential in the preparation of double metal cyanide (DMC) catalyst, which exhibits excellent catalytic activity for the solvent-free cycloaddition of CO2 and propylene oxide (PO). Effective Zn–Fe DMC catalysts with cetyltrimethylammonium bromide (CTAB) were successfully obtained via ball milling. The characterization of Zn–Fe DMCs confirmed that CTAB was incorporated into the structure of DMC and the particle size ranges from 79 nm to a minimum of 25 nm. The DMC complex was proven to be an effective catalyst for the cycloaddition of CO2 and propylene oxide (PO) (140 °C, 3 MPa, 6 h). The cyclic carbonate exhibited high conversion from 88.9% to 98.3% with high selectivity.