METHOD FOR PRODUCING PENTAERYTHRITOL DIPHOSPHONATE

摘要

PROBLEM TO BE SOLVED: To provide an industrially advantageous method for producing pentaerythritol diphosphonate in excellent productivity. SOLUTION: The method for producing the pentaerythritol diphosphonate comprises washing a crude product of the pentaerythritol diphosphonate with a cleaning liquid containing≥50 wt.% organic solvent having 10-40 dielectric constant at 25°C to provide the purified pentaerythritol diphosphonate, reusing the cleaning liquid after the cleaning as the cleaning liquid for the crude product of the pentaerythritol diphosphonate to provide the purified pentaerythritol diphosphonate. The cleaning liquid to be reused contains≥50 wt.% organic solvent having 10-40 dielectric constant at 25°C. COPYRIGHT: (C)2004,JPO