| 摘要 |
The invention concerns a method for purifying acrylic acid so as to eliminate the impurities of polymer type in parts of distillation columns where they tend to accumulate, in particular for eliminating the polymeric impurities which are formed during a step of eliminating acrylic acid aldehyde impurities, step whereby a distillation of the medium containing the acrylic acid to be purified is carried out by adding in this medium at least one amino compound of the hydrazine type and by purging, at the foot of the distillation column, heavy compounds formed by the amino compound(s) of the hydrazine type with the impurities. The distillation of the acrylic acid to be purified is also carried out in the presence of at least one compound of the class of non-ionic surfactants and at least one polymerisation inhibitor. As non-ionic surfactants can be mentioned polysaccharide ethers and acetates, in particular ethers derived from cellulose or starch.
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