In the liquid phase methanol synthesis process in a mechanically agitated slurry reactor (MASR), catalyst particles in powder form are slurried in the oil phase, and this catalyst-oil slurry is continuously agitated by the impeller in the reactor. Syngas, which is fed to the reactor, reacts in the presence of the activated catalyst-oil slurry, to form the product, methanol. A computer model was developed based on the experimental results, for the liquid phase methanol synthesis process, in a mechanically agitated slurry reactor. This computer program accurately predicts the multicomponent phase equilibria, ultimate chemical equilibria, and the compositions of each reactant and product species exiting in the agitated slurry reactor. The results of the modeling predictions, agree well with the experimental data collected from the agitated slurry reactor.