| 摘要 |
<p>The acrylic acid, esp. that made by catalytic oxidn. of propylene, is continuously purified, without any pre-processing, by addn. of a hydrazine cpd. of formula RR1-N=N-NH2, in which R and R1 are H, or opt. substd. alkyl or aryl, in amt. of 2-4 moles per mole of carbonyl impurity in the acrylic acid. The stream of treated acid is mixed with alcohol, passed through a heat exchanger in which the esterification catalyst is added, and then into a standard reactor.</p> |
