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US 8,524,047 B2Granted
Method of dehydrating tolylenediamine and dehydrator
AssigneeMitsui Chemicals, Inc.
InventorsToshiyuki Ogawa, Mitsunaga Dohzaki, Masaaki Sasaki
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Abstract
A method of dehydrating tolylenediamine which includes subjecting tolylenediamine having a water content of 5-40 wt. % to first-stage distillation at a vacuum of 13-101.3 kPa and subjecting the bottoms from the first-stage distillation to second-stage distillation at a vacuum lower than 13kPa.
Claims4
A method of dehydrating tolylenediamine, comprising:
- subjecting tolylenediamine having a water content of 5 to 40% by weight to first-stage distillation at a vacuum degree of 13 to 101.3 kPa,
- subjecting bottoms from the first-stage distillation to second-stage distillation at a vacuum degree of less than 13 kPa, and
- refluxing the distillate from the second-stage distillation set to have a water content of 5 to 70% by weight to the first-stage distillation.
Dependencies are inferred from the claim text.