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Incipient wet impregnation method ( ≡SiO) 3 V=O, polymeric species, bulk crystalline V 2 O 5 Catalytic site : tetrahedral mono vanadate ( ≡SiO) 3 V=O. Grafting Method for Vanadium Loading. Batch 1 Calcined ZSM-5 + anhydrous toluene : reflux in N 2 for 5h to remove any absorbed water
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Incipient wet impregnation method (≡SiO)3V=O, polymeric species, bulk crystalline V2O5 Catalytic site : tetrahedral mono vanadate (≡SiO)3V=O
Grafting Method for Vanadium Loading Batch 1 Calcined ZSM-5 + anhydrous toluene : reflux in N2 for 5h to remove any absorbed water Batch 2 150mL Toluene+0.4mlVOCl3/4g Cat +20mL Ethanol 150mL Toluene+0.8mlVOCl3/4g Cat + 20mL Ethanol 150mL Toluene+1.2mlVOCl3/4g Cat +20mL Ethanol Reflux with N2 bubbling from the bottom for 8h Remove excess ethanol Reflux (Batch 1 + Batch 2) at 100C for overnight in N2 atmosphere Cool down the mixture, centrifuge, washing with Toluene Calcine the solid
Chemicals in Grafting • With moisture • VOCl3 + 3H2O ↔ VO(OH)3 + HCl • difficult for condensation with silanol • - VOCl3 + 3C2H5OH ↔ VO(OCH2CH3)3 + 3HCl • VO(OCH2CH3)3 + 3(HO-ZSM-5) • VO(- O-Si-O)3 + 3CH3CH2OH
Oil 200g / MeOH 66.6g / Cat 1.3g At 120, 170C Ea=45KJ/mol when 1st order rxn 9.3mmol/gcat h at170C 120C 3.8mmol/gcat h at120C