PROCESS FOR PRODUCING ISOCYANATE

摘要

A process for producing an isocyanate without using phosgene. The process has none of various problems encountered in prior art techniques and enables an isocyanate to be stably produced in high yield for long. The process is for producing an isocyanate by subjecting a carbamic acid ester to pyrolytic reaction. The process includes: a step in which low-boiling ingredients are recovered as a gas-phase ingredient from a pyrolysis reactor where the pyrolytic reaction is conducted; a step in which a liquid-phase ingredient containing the carbamic acid ester is recovered through a bottom part of the pyrolysis reactor; and a step in which part or all of the liquid-phase ingredient is supplied to an upper part of the pyrolysis reactor.