Catalyst | Regeneration process (washing with solvent, calcination temperature) | FAME yield [%] | Ref. |
CaO from mud clam shells | n-hexane, 900˚C | 96.7 to 74.5 | [28] |
CaZnO | n-hexane, MeOH, 800˚C (3 h) | 80 to <80 | [29] |
CaO from biomass | Acetone, EtOH, 600˚C - 800˚C (4 h) | 75 to 50 | [30] |
CaO from waste cockle shells | MeOH, n-hexane, 900˚C (2 h) | >97 | [31] |
Modified red mud | n-hexane, 700˚C (2 h) | 99.6 to 96.8 | This study |