Micro-chemical plants increased production by the parallelization of microdevices. The uniform distribution of flow through the microdevices are made by the flow distributor. Inadequate distributor design reduces the micro-chemical plant performance. The present research aims to perform a numerical analysis of distributor designs. Three designs were evaluated varying the distributor height and the presence or absence of internal obstacle. Analyses of flow rate and phase distribution uniformity and the prediction of biodiesel synthesis occurrence inside the distributors were performed. Different numerical approaches were used for the specific systems, including single-phase flow, multi-component flow and Volume of Fluid (VOF) simulations. The VOF-based model provided good agreement with experimental data of water flow. The viscous dominated oil flow, presented good distribution in all proposed designs. Water and ethanol presented bulk recirculation inside the distributor, depreciating the flow uniformity. The ethanol-oil mixture flow resulted in high flow nonuniformity and in the occurrence of biodiesel synthesis for all operating conditions. Based on the numerical predictions, the micro-chemical plants require two distributors in order to perform the transesterification reaction only inside the microdevices. The simulations were employed as a design tool providing flow details and substantiating the project optimization for further development of micro-chemical plants. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.