Method for preparing isocyanate through supercritical phosgenation reaction

• Main Authors: QIU GUISEN, LIU WENJIE, XUE YONGHE, LIU JIATE, LU CHENGLIANG, YUAN HAIXIN
• Format: Patent
• Language: Chinese; English
• Published: 27.09.2022
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

The invention relates to a method for preparing isocyanates. Specifically, the present application provides a method for preparing isocyanate by performing a phosgenation reaction under supercritical conditions, the method comprising the steps of: (a) mixing a reactant amine stream and a phosgene stream at a temperature of-5 to 5 DEG C to obtain a mixture of reactant amine and phosgene; (b) adjusting the temperature of the mixture obtained in the step (a) to 182-205 DEG C so that the phosgene is in a supercritical state, and reacting in a supercritical reactor for at least 20 minutes; and (c) adjusting the temperature of the supercritical reactor to 200 DEG C or above, and stirring to react for at least 2 hours. 本申请涉及一种制备异氰酸酯的方法。具体地，本申请提供了一种在超临界条件下进行光气化反应来制备异氰酸酯的方法，所述方法包括以下步骤：(a)将反应物胺料流和光气料流在-5至5℃的温度下进行混合，得到反应物胺和光气的混合物；(b)将步骤(a)得到的混合物的温度调节为182℃～205℃，使得所述光气处于超临界状态，在超临界反应器中进行反应至少20分钟；(c)将所述超临界反应器的温度调节至200℃以上，搅拌反应至少2小时。