摘要 |
An improved process for making a high purity, crystalline aromatic dicarboxylic acid product which includes at least one step for crystallizing the product and wherein the crystallized product is thereafter subjected to a drying step. The improved process further includes the steps of storing the crystallized product for a period of time sufficient for at least a portion of residual solvent carried with the dried crystallized product to reside on a surface of the crystalline product; and contacting the stored crystallized product with an inert fluid for a time sufficient to remove at least a portion of the residual solvent in the stored crystallized product. Purified crystalline aromatic dicarboxylic acids suitable for the present improved process include benzene dicarboxylic acid, naphthalene dicarboxylic acid, bibenzoic acid, terephthalic acid, and isophthalic acid. Particularly preferred aromatic dicarboxylic acids include terephthalic acid, and isophthalic acid. ® KIPO & WIPO 2007
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