| abstract |
A reaction column ( 12 ) to which a raw material mixture ( 11 ) containing a mono-lower-alkylamine (AA: raw material I) and an alkylene oxide (AO: raw material II) is supplied, an unreacted raw material distillation column ( 14 ) that separates an unreacted raw material ( 15 ) from a reaction product ( 13 a ) (containing the unreacted raw material ( 15 ), a target reaction product (monomer) ( 17 ), and a by-product (dimer) ( 18 )), and a flash drum ( 16 ) to which a reaction product ( 13 b ) (containing the target reaction product (monomer) ( 17 ) and the by-product (dimer) ( 18 )) is supplied, the flash drum ( 16 ) separating a mono-lower-alkyl monoalkanolamine (monomer, the target reaction product 17 ) in a gas state, are provided. |