Table 9.
Different reaction conditions affecting production of propylene glycol.
| S. No. |
Reactants (Molar ratio) | Catalyst (amount) | Optimal reaction condition(s) | Product (s) | Reference |
|---|---|---|---|---|---|
| 1. | Glycerol:Solvent (1:4) | Cu on acid treated fly ash (1 g) | 220 ◦C, 5 hour, 52 bar | 1,2-propanediol | [107] |
| 2. | 80 % glycerol solution | copper-chromite | 200 ◦C, 24 hour, 200 psi | propylene glycol | [108] |
| 3. | 40 wt.% of aqueous glycerol solution | Cu/SiO2 IE (1 g) | 200 ◦C, 15 bar, 7 hour | 1,2-propanediol | [109] |
| 4. | Glycerol in water | CuO–ZnO (5 mol%) | 180 ◦C, 80 bar, 48 hour | 1,3-propanediol, 1,2-propanediol | [110] |
| 5. | Aqueous glycerol | Cu/Zn/Al – 5 wt. % | 200 psig, 200 ◦C, 24 hour | Propylene Glycol | [111] |
| 6. | H2:Glycerol (2:1) | Mo and W catalysts (3 mL) | 60 bar, 24 hours, 325 ◦C | 1,2-propanediol | [112] |
| 7. | 1 wt.% glycerol solution | carbon-supported Ru and Pt catalysts | 200 ◦C, 40 bar H2, 5 hour |
Propylene Glycol | [113] |
| 8. | 10 vol% glycerol solution | Cu-Ni catalysts (1.25 g) | 250 ◦C, 40 bar, 6 hour | Propylene Glycol | [114] |
| 9. | 50 wt.% glycerol concentration | H-beta supported Ni-Zr catalyst (0.5 g) | 600 psi, 10 hour, 200 ◦C | Propylene Glycol | [115] |
| 10. | 10 wt% aqueous solution of glycerol | B2O3 Promoted Cu/Al2O3 Catalyst (2 g) |
250 ◦C, 6 MPa | 1,2-Propanediol | [116] |
| 11. | H2/Glycerol (10:1) | Copper over alumina and copper chromite (4 g) | 230◦C, 14 bar, 4 hour | 1,2-PDO | [117] |