摘要:
An organic solvent free method for purifying and refining of a long-chain dicarboxylic acid or a salt thereof is disclosed. This method avoids problems caused by organic solvents which have been used in the purifying process of the prior art. This method reduces effectively the content of such impurities as proteins and coloring materials in the product. The purity of the crystallized long-chain dicarboxylic acid product is greater than 99 wt %.