| 摘要 |
An aqueous 30 wt. % solution of formaldehyde trickled with an equal volume of NaOH solution over a zeolite (NaX, 5A, or Na Mordenite) at 94 DEG C., 1 atm, 1.21-2.36 liquid hourly space velocity, catalytically condenses to HOCH2CHO, glycolaldehyde, a fraction of which then converts to HOCH2CH2OH, ethylene glycol, by cross-Cannizzaro side reaction. Zeolite degradation is prevented by maintaining pH near 11. Selectivity can be controlled so that less than 1% byproduct formose sugars are made. Methanol and sodium formate are also byproducts. All of the remaining glycolaldehyde could, in principle, be converted to ethylene glycol in either a subsequent cross-Cannizzaro reaction or a hydrogenation step. Thus, the reaction represents a potential non-petrochemical route for either glycolaldehyde or ethylene glycol from CO+H2, via methanol and formaldehyde.
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