The flow, temperature and concentration characteristics in micro-reactors are inherently different from those in macro-reactors. In the former, slip-flow is important. In the case of heterogeneous chemical reaction, jump in the wall temperature and concentration also occur. In this study, we describe the two-dimensional model simulation of the gas velocity, temperature, and concentration in micro-reactors, using lattice Boltzmann methods (LBM). Slip (or jump) in all three transport variables (flow, temperature, and concentration) are considered. The results show two-dimensional profiles of the velocity, temperature, and concentration in the reactors. Due to simultaneous heat and mass transfer, Nusselt number (Nu) and Sherwood number (Sh) are shown to be dependent on a number of variables, including Knudsen number (Kn), transport accommodation coefficients, and the reaction rate. The results in this study assume significance from the perspective of understanding flow and transport characteristics in microreactors. (C) 2010 Elsevier Ltd. All rights reserved.