摘要 |
A process for inhibiting free-radical polymerization of an alpha,beta-unsaturated (alpha,beta-unsaturated) carboxylic acid, and for providing desired grade alpha,beta-unsaturated carboxylic acid for use following storage and transport is described herein. In particular, bulk storage and shipment such as with overseas transport is described. The process comprises combining the alpha,beta-unsaturated carboxylic acid with a phenolic inhibitor and a coinhibitor to form an inhibited mixture, storing the inhibited mixture, transporting the inhibited mixture, and removing the coinhibitor to provide the desired grade alpha,beta-unsaturated carboxylic acid for use. In preferred embodiments, the alpha,beta-unsaturated carboxylic acid is acrylic acid, the phenolic inhibitor is p-methoxyphenol, the coinhibitor is manganese cation, and removal of the coinhibitor is carried out using an ion exchange resin.
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