| 摘要 |
A purification method of crude naphthalene dicarboxylic acid is provided to improve economical efficiency, purification yield and purity by purifying the acid with a microorganism converting FNA(2-formyl-6-naphthoic acid) into NDA(naphthalene dicarboxylic acid) at room temperature and pressure, so that pure 2,6-naphthalene dicarboxylic acid in crystalline form is mass produced. A purification method of crude naphthalene dicarboxylic acid comprises the steps of: (a) washing the crude naphthalene dicarboxylic acid with water of 150-200 deg. C to remove impurities; (b) mixing the washed crude naphthalene dicarboxylic acid with buffer solution, and adding alkali solution into the mixture to prepare purification reaction solution; (c) reacting the purification reaction solution with a microorganism converting FNA(2-formyl-6-naphthoic acid) into NDA(naphthalene dicarboxylic acid) to remove 2-formyl-6-naphtholic acid from the crude naphthalene dicarboxylic acid; (d) adding acidic solution into the resulting solution of step (c) to regulate pH to 1-4, and stirring the mixture at 0-1000 rpm to crystallize the crude naphthalene dicarboxylic acid; (e) washing the crystalline crude naphthalene dicarboxylic acid with water of 30-100 deg.C to remove salts; and (f) drying the washing product to obtain pure 2,6-naphthalene dicarboxylic acid, wherein the microorganism converting FNA into NDA is Bacillus sp. F-1(KCTC-10342BP), Bacillus sp. F-3(KCTC-10355BP) or Pseudomonas sp. NH-72(KICTC-10819BP). Further, the buffer solution is one or more selected from a group of H2O, Na2OX/NaHCO3, Glycine/NaOH, KH2PO4/KOH, Na2HPO4/NaH2PO4, Succinic acid/NaOH, Sodium acetate/Acetic acid, Citric acid/Sodium citrate, Na4P2O7/HCl, Boric acid/NaOH and Sodium borate/HCl. |
