Economic and environmental assessment of reactive distillation process for cyclohexanol production with different purity intermediates

Given the rising demand for cyclohexanol in the nylon industry and the escalating issues of high production costs and potential environmental harm in traditional cyclohexanol production, developing a safe, environmentally friendly, and cost-effective process for producing cyclohexanol from cyclohexene is crucial. In addition, the different composition of intermediates will significantly affect the economy of each reaction unit. Therefore, this study proposed a novel reactive distillation process involving esterification, transesterification, and hydrolysis. Three reactive distillation processes of 1000 t/a capacity of cyclohexanol production with different purity intermediates were designed and optimized using a sequential iterative algorithm to minimize the total annual cost, which amounted to 422116.65 $/a. Furthermore, the energy consumption and environmental emissions were compared after optimization. By comparing the influence of various purity intermediates on each process unit, it was qualitatively determined that higher purity requirements did not necessarily yield superior results. Finally, to quantify the influence of each variable on economic performance of whole process, response surface method was performed using central composite design for minimum total annual cost objectives with a 3.25 % error between model and simulation. This study aims to guide the development of a comprehensive, cost-effective, and efficient reactive distillation process for cyclohexanol production.