摘要 |
Formic acid cannot be completely removed from formic acid and water mixtures by distillation because of the presence of the maximum azeotrope. Formic acid can be readily removed from formic acid - water mixtures by extractive distillation in which the extractive agent is ethylene carbonate or propylene carbonate, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are ethylene carbonate and heptanoic acid; propylene carbonate, benzoic acid and isophorone; propylene carbonate, heptanoic acid and 2-hydroxyacetophenone.
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