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How to dry toluene using molecular sieves?
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+ Drying
+ Toluene
+ Polymer chemistry
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Nuruzzaman Jony
How to dry toluene using molecular sieves?
Dear Xuewei, Molecular sieve (MS) should be added to the toluene at least 48 hours before use in order to adsorb any water molecules present. "Monomethoxy polyethylene glycol was dissolved in anhydrous toluene and heated under reflux for 24 h at 50°C, 70 mbar, and water was removed from the azeotropic mixture using dried molecular sieves (0.4 nm)." The above statement indicates that MS also was added to the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene to remove water molecules present. Summary: 1-MS is added to toluene 48 hours before use. 2-MS is added to the reaction mixture to adsorb water molecules present in the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene. Hoping this will be helpful, Rafik
Dear Xuewei, Molecular sieve (MS) should be added to the toluene at least 48 hours before use in order to adsorb any water molecules present. "Monomethoxy polyethylene glycol was dissolved in anhydrous toluene and heated under reflux for 24 h at 50°C, 70 mbar, and water was removed from the azeotropic mixture using dried molecular sieves (0.4 nm)." The above statement indicates that MS also was added to the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene to remove water molecules present. Summary: 1-MS is added to toluene 48 hours before use. 2-MS is added to the reaction mixture to adsorb water molecules present in the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene. Hoping this will be helpful, Rafik
Dear all, thanks a lot for the helpful answer. Does anyone happen to know how to separate MS with the solvent mixture to run the following reaction and make sure no new moisture is introduced? Or the following reaction could occur in the presence of MS and MS could be separated after the reaction?
Dear all, thanks a lot for the helpful answer. Does anyone happen to know how to separate MS with the solvent mixture to run the following reaction and make sure no new moisture is introduced? Or the following reaction could occur in the presence of MS and MS could be separated after the reaction?
About toluene drying ― You may consider drying toluene with CaH2, with anhydrous CuSO4 or MgSO4, or with type 4A molecular sieves (≥ 3% g/cm3); and (preferably) further fractionally distilling it from its mixture with the added desiccant, or/and from added P2O5; but rejecting the very first distillate, possibly up to a few wt%, if distilled at what may be judged as significantly below the normal boiling point of pure toluene (110.6 °C), preferably corrected for the actual atmospheric pressure. You can conveniently store dried toluene over 4A (or 3A) molecular sieves.
About toluene drying ― You may consider drying toluene with CaH2, with anhydrous CuSO4 or MgSO4, or with type 4A molecular sieves (≥ 3% g/cm3); and (preferably) further fractionally distilling it from its mixture with the added desiccant, or/and from added P2O5; but rejecting the very first distillate, possibly up to a few wt%, if distilled at what may be judged as significantly below the normal boiling point of pure toluene (110.6 °C), preferably corrected for the actual atmospheric pressure. You can conveniently store dried toluene over 4A (or 3A) molecular sieves.
Dear Xuewei,
Molecular sieve (MS) should be added to the toluene at least 48 hours before use in order to adsorb any water molecules present.
"Monomethoxy polyethylene glycol was dissolved in anhydrous toluene and heated under reflux for 24 h at 50°C, 70 mbar, and water was removed from the azeotropic mixture using dried molecular sieves (0.4 nm)."
The above statement indicates that MS also was added to the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene to remove water molecules present.
Summary:
1-MS is added to toluene 48 hours before use.
2-MS is added to the reaction mixture to adsorb water molecules present in the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene.
Hoping this will be helpful,
Rafik
Dear Xuewei,
Molecular sieve (MS) should be added to the toluene at least 48 hours before use in order to adsorb any water molecules present.
"Monomethoxy polyethylene glycol was dissolved in anhydrous toluene and heated under reflux for 24 h at 50°C, 70 mbar, and water was removed from the azeotropic mixture using dried molecular sieves (0.4 nm)."
The above statement indicates that MS also was added to the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene to remove water molecules present.
Summary:
1-MS is added to toluene 48 hours before use.
2-MS is added to the reaction mixture to adsorb water molecules present in the azeotropic mixture of Monomethoxy polyethylene glycol and anhydrous toluene.
Hoping this will be helpful,
Rafik
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Dear Xuewei,
You can run the following reaction in the presence of MS and in the final stage you can make the filtration process.
Rafik
Dear Xuewei,
You can run the following reaction in the presence of MS and in the final stage you can make the filtration process.
Rafik
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Dear all, thanks a lot for the helpful answer. Does anyone happen to know how to separate MS with the solvent mixture to run the following reaction and make sure no new moisture is introduced? Or the following reaction could occur in the presence of MS and MS could be separated after the reaction?
Dear all, thanks a lot for the helpful answer. Does anyone happen to know how to separate MS with the solvent mixture to run the following reaction and make sure no new moisture is introduced? Or the following reaction could occur in the presence of MS and MS could be separated after the reaction?
More
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About toluene drying ― You may consider drying toluene with CaH2, with anhydrous CuSO4 or MgSO4, or with type 4A molecular sieves (≥ 3% g/cm3); and (preferably) further fractionally distilling it from its mixture with the added desiccant, or/and from added P2O5; but rejecting the very first distillate, possibly up to a few wt%, if distilled at what may be judged as significantly below the normal boiling point of pure toluene (110.6 °C), preferably corrected for the actual atmospheric pressure. You can conveniently store dried toluene over 4A (or 3A) molecular sieves.
About toluene drying ― You may consider drying toluene with CaH2, with anhydrous CuSO4 or MgSO4, or with type 4A molecular sieves (≥ 3% g/cm3); and (preferably) further fractionally distilling it from its mixture with the added desiccant, or/and from added P2O5; but rejecting the very first distillate, possibly up to a few wt%, if distilled at what may be judged as significantly below the normal boiling point of pure toluene (110.6 °C), preferably corrected for the actual atmospheric pressure. You can conveniently store dried toluene over 4A (or 3A) molecular sieves.
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Dear all,
normally you should use dry toluene in a azeotropic distillation using a Dean-Stark set up. Regards
Dear all,
normally you should use dry toluene in a azeotropic distillation using a Dean-Stark set up. Regards
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