Title:
Isocyanate production method
Document Type and Number:
Japanese Patent JP6316491
Kind Code:
B2
Abstract:
A method for producing an isocyanate, comprising: a carbamation step of generating an N-substituted carbamate from an organic primary amine, urea and an organic hydroxy compound according to a carbamation reaction, and then recovering a first gaseous phase component containing the urea and/or a compound having a carbonyl group derived from the urea, the organic hydroxy compound, and ammonia; a condensation step of condensing the first gaseous phase component with a condenser; an isocyanate production step of producing an isocyanate by subjecting the N-substituted carbamate to pyrolysis; an ammonia absorption step of allowing a second gaseous phase component containing ammonia recovered as a gaseous phase component from the condenser as a main component, to be absorbed by absorption water, and generating gas-absorbed water; and an ammonia stripping step of heating the gas-absorbed water to separate ammonia from the gas-absorbed water.
Inventors:
Shinohata Masaaki
Takeuchi Koji
Naoki Fujimoto
Nobuhisa Miyake
Takeuchi Koji
Naoki Fujimoto
Nobuhisa Miyake
Application Number:
JP2017142945A
Publication Date:
April 25, 2018
Filing Date:
July 24, 2017
Export Citation:
Assignee:
ASAHI KASEI KABUSHIKI KAISHA
International Classes:
C07C263/04; C07C265/12; C07C265/14
Domestic Patent References:
| JP2005068146A | ||||
| JP2005068147A | ||||
| JP2005068148A | ||||
| JP2012509301A | ||||
| JP2012233014A |
Foreign References:
| WO2012115110A1 |
Attorney, Agent or Firm:
Yoshiki Hasegawa
Yoshinori Shimizu
Hiroyuki Nishimoto
Naoshi Fukuyama
Yoshinori Shimizu
Hiroyuki Nishimoto
Naoshi Fukuyama
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