The utilization of CO2 as raw material for chemical synthesis has the potential for substantial economic and green benefits. Thermal decomposition of hexamethylene-1,6-dicarbamate (HDC) is a promising approach for indirect utilization of CO2 to produce hexamethylene-1,6-diisocyanate (HDI). In this work, a green route was developed for the synthesis of HDI by thermal decomposition of HDC over Co3O4/ZSM-5 catalyst, using chlorobenzene as low boiling point solvent. Different metal oxide supported catalysts were prepared by incipient wetness impregnation (IWI), PEG-additive (PEG) and deposition precipitation with ammonia evaporation (DP) methods. Their catalytic performances for the thermal decomposition of HDC were tested. The catalyst screening results showed that Co3O4/ZSM-5(25) catalysts prepared by different methods showed different performances in the order of Co3O4/ZSM-5(25(PEG)) > Co3O4/ZSM-5(25(IWI)) > Co3O4/ZSM-5(25(DP)). The physicochemical properties of Co3O4/ZSM-5(25) catalyst were characterized by XRD, FTIR, N-2 adsorption-desorption measurements, NH3-TPD and XPS. The superior catalytic performance of Co3O4/ZSM-5(25(PEG)) catalyst was attributed to its relative surface content of Co3+, surface lattice oxygen content and total acidity. Under the optimized reaction conditions: 6.5% HDC concentration in chlorobenzene, 1 wt% Co3O4/ZSM-5(25(PEG)) catalyst, 250 degrees C temperature, 2.5 h time, 800 ml . min(-1) nitrogen flow rate and 1.0 MPa pressure, the HDC conversion and HDI yield could reach 100% and 92.8% respectively. The Co3O4/ZSM-5(25(PEG)) catalyst could be facilely separated from the reaction mixture, and reused without degradation in catalytic performance. Furthermore, a possible reaction mechanism was proposed based on the physicochemical properties of the Co3O4/ZSM-5(25) catalysts. (C) 2017 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.