The production of higher alcohols over a sulfidized molybdenum catalyst (MoS2) using a biomass-derived synthesis gas has been studied at Gussing for several years. The mixed alcohol (MA) pilot plant uses synthesis gas provided by the biomass-based combined heat and power plant (CHP) Gussing. Parameter variations were carried out wherein temperature, space velocity and gas composition were varied to evaluate the impact on CO conversion, product distribution and yield. The influence of side reactions to hydrocarbons was also a research objective. A sufficient amount of experimental data was obtained during these experiments. Evidence for the influence of various reaction parameters was found, but the mass balance could not be closed. A mathematical model of the MA synthesis reactor was developed using the stationary equation-orientated flow sheet simulation software IPSEpro. This publication gives an overview of modeling the MA reactor and condenser unit and testing the model with example calculations. Validated experimental results from 2012 parameter variation are shown and a comparison between experimental and validated quantities is carried out. A comparison with literature data shows that the observed tendencies are in good correlation to literature. The developed reactor model was enabling the possibility for carrying out a validation of the experimental data. IPSEpro uses the method of least-squares to obtain the approximate solution of the overall determined system. The established model was very close to the actual MA pilot plant. The model is very accurate about MA liquid product compositions and all measured flows. (C) 2015 Elsevier B.V. All rights reserved.