| 摘要 |
Crude 1,10-decanedicarboxylic acid produced by the nitric acid oxidation at 20 DEG 14 60 DEG C. of cyclododecanone, cyclododecanol or a mixture thereof can be purified by distillation to a purity suitable for use in the production of polyamides and polyesters by reducing prior to distillation, e.g., by heating to 70 DEG -90 DEG C., the organically bound nitrogen content and as required the nitric acid content, e.g., by washing, and water content thereof so that the sample which is distilled has maximum contents thereof of 0.05%, 0.02% and 0.1% by weight, respectively, and distilling the pre-purified sample at a sump temperature of 215 DEG -225 DEG C. and at a pressure of 0.5 - 2 torr.
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