Time on stream was used because an activation-deactivation process was observed (see Figure ) during the measurement of the catalyst activity in CO2 hydrogenation. The ANN was used for predicting the reaction rates ( ) -( ) as well as the suggested parameters (𝛼 𝑎𝑛 1 , 𝛼 𝑎𝑛 2 , 𝛼 𝑒𝑛 , 𝛼 𝑂𝐻 , 𝛿 𝑒𝑛 , 𝛿 𝑂𝐻 , and 𝜇). Thus, the number of outputs for each a node of the hidden layer was 12. For the hidden layer of the ANN with a hyperbolic tangent activation function 8 nodes were used. The model takes into consideration the formation of alkanes and alkenes (up to 15 carbon number), and alcohols (up to 7). Before training the value of total pressure was scaled by dividing by the maximum total pressure and time-on-stream was scaled by dividing by the maximum value of time-on-stream in the experimental data set.