Question

Liquid ethanol is burned with 20% excess amount of air (21% oxygen and 79% nitrogen). The feed ethanol (liquid) and air are at 50^oC and the products of carbon dioxide and water are in gas state. Find the potential maximum temperature (T (K)) of the existing stream, which includes the products and the unreacted oxygen and nitrogen. The pressure of the feed and the existing stream is one atmosphere.

                                    C₂H₅OH (l)     +    3O₂ (g) -------à     2CO₂ (g)       +     3 H₂O (g)

1. Clearly state your assumptions to solve this problem
2. Draw the diagram of the enthalpy changes of the chemical reactions that are at different temperatures and involves sensible heat and standard heat of chemical reaction at 25^oC
3. Use the energy balance equation for open system and write the energy balance equation of part (2)
4. Find the potential maximum temperature of the existing stream by solving the energy balance equation of part (3). .

Answer 1