In this study, a two-stage fluidized bed reactor (TS-FBR) was designed as a new technology to produce diethyl oxalate (DEO) from carbon monoxide (CO) based on the catalytic coupling reaction. Computational fluid dynamics (CFD) approach was adopted to obtain the detailed flow field, the bubble behaviors in the TS-FBR, and further demonstrate the feasibility of the TS-FBR used in producing DEO from CO. Furthermore, the whole preparation process of DEO from CO using the optimum TS-FBR as the central unit is simulated using an advanced software tool, realizing the proper matching of coupling reaction and regeneration reaction. As a result, the realization of the whole preparation process is presented. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.