PROCESS FOR RECOVERING TOLUENE DIAMINE FROM SOLID WASTE DISCHARGED FROM TOLUENE DIISOCYANATE PRODUCTION PROCESS THROUGH PRETREATMENT AND CATALYTIC HYDROLYSIS WITH HIGH YIELD

• Main Authors: DO, SEUNG HOE, SHIN, YEONG HO, HAN, GI U, HAN, JU HUI, HAN, GI DO, JUNG, CHANG MO
• Format: Patent
• Language: English; Korean
• Published: 17.12.2004
• Edition: 7
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

PURPOSE: Provided is a process for recovering toluene diamine from solid waste discharged from a toluene diisocyanate production process, which reduces the generation of waste water and waste product, and increases reutilization efficiency during the process. CONSTITUTION: The process for recovering toluene diamine from solid waste(10) discharged from a toluene diisocyanate production process comprises the steps of: pulverizing and screening the solid waste; mixing the treated solid waste with water(11) and a catalyst(12) to form slurry; pressurizing the slurry, introducing it continuously into a heat exchanger(22) and heating the slurry with a treating liquid discharged from a reactor(24) while cooling the treating liquid; warming the slurry to a liquid phase zone having a temperature of 200-370 deg.C less than the critical point of water to hydrolyze the organic particles in the slurry; cooling the hydrolyzed slurry by the heat exchange with the treating liquid discharged from the reactor and reducing the internal pressure; introducing the treating liquid into a distillation tower(31) to discharge a mixed gas(34) at the top and a mixture(35) of toluene diamine, the catalyst and high-boiling tar at the bottom; and introducing the mixture into a depressurization evaporator(41) to recover toluene diamine(42) at the top and to discharge a mixture of the catalyst and tar as waste products(43) at the bottom.