METHOD FOR PRODUCING ISOCYANATE

• Main Authors: SAKURAI YUSUKE, SHINOHATA MASAAKI, MIYAKE NOBUTOSHI
• Format: Patent
• Language: English; Japanese
• Published: 21.11.2019
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

To provide a method for producing isocyanate that suppresses a side reaction and continuously produces isocyanate.SOLUTION: The present invention provides a method for producing isocyanate by pyrolysis of carbamate, the method including: a pyrolysis step in which a liquid mixture containing carbamate and a cyclic compound of a specific structure is continuously introduced into a pyrolytic reactor for a pyrolytic reaction of carbamate; a low-boiling-point pyrolytic product recovery step in which a low-boiling-point pyrolytic product having a normal boiling point lower than that of the cyclic compound is continuously extracted in a gas state from the pyrolytic reactor; and a high-boiling-point component recovery step in which a liquid phase component, which has not been recovered in a gas state in the low-boiling-point pyrolytic product recovery step, is continuously extracted as a high-boiling-point component from the pyrolytic reactor.SELECTED DRAWING: None 【課題】副反応を抑制し、連続的にイソシアネートを製造するイソシアネートの製造方法を提供する。【解決手段】イソシアネートの製造方法は、カルバメートの熱分解によってイソシアネートを製造する方法であって、カルバメートと、特定の構造を有する環式化合物とを含む混合液を、熱分解反応器に連続的に導入して、カルバメートの熱分解反応を行う熱分解工程と、前記環式化合物よりも標準沸点が低い低沸点分解生成物を、前記熱分解反応器から気体状で連続的に抜き出す低沸点分解生成物回収工程と、前記低沸点分解生成物回収工程で気体状で回収されなかった液相成分を高沸点成分として前記熱分解反応器から連続的に抜き出す高沸点成分回収工程と、を含む方法である。【選択図】なし