At the fifth recycling, the glycerol conversion and glycerol carbonate
yield for the recovered CaO/Al2O3(polya, 3) catalyst still can reach 65.47% and 62.53%, respectively, which
are far higher than for CaO powder catalyst. The extruded catalyst also has a certain water-resistance performance.
The catalyst characterization shows the active site of the extruded CaO-based catalyst is CaO.
The extruded catalyst not only has higher surface area, higher pore volume, and larger pore diameter, but
also higher mechanical strength, and can be used for the industrial process for producing glycerol
carbonate.