I tried to replicate your problem as much as possible, see here for my code:

import numpy as np

import matplotlib.pyplot as plt

# Constants

R = 8.314 # J/(mol·K), universal gas constant

T = np.linspace(300, 2000, 500) # Temperature range in Kelvin

# Gibbs free energy of formation (J/mol)

G_Fe3O4 = -1017400 # for Fe3O4

G_FeO = -259400 # for FeO

G_CO2 = -394360 # for CO2

G_CO = -137170 # for CO

G_Fe = 0 # for Fe (standard state)

# Reaction 1: 1/4 Fe3O4 + CO 3/4 Fe + CO2

delta_G_reaction1_298 = (3/4 * G_Fe + G_CO2) - (1/4 * G_Fe3O4 + G_CO)

delta_G_reaction1 = delta_G_reaction1_298 # Assuming temp-independent ΔG for now

# Reaction 2: Fe3O4 + CO 3FeO + CO2

delta_G_reaction2_298 = (3 * G_FeO + G_CO2) - (G_Fe3O4 + G_CO)

delta_G_reaction2 = delta_G_reaction2_298 # Assuming temp-independent ΔG for now

# Calculate equilibrium constants

K1 = np.exp(-delta_G_reaction1 / (R * T))

K2 = np.exp(-delta_G_reaction2 / (R * T))

# Calculate P(CO) assuming P(CO) + P(CO2) = 1 atm

P_CO1 = 1 / (1 + K1)

P_CO2 = 1 / (1 + K2)

# Plotting

plt.figure(figsize=(10, 6))

plt.plot(T, P_CO1, label=r'Reaction 1: $P(CO)$')

plt.plot(T, P_CO2, label=r'Reaction 2: $P(CO)$', linestyle='--')

plt.xlabel('Temperature (K)')

plt.ylabel(r'$P(CO)$ (atm)')

plt.title('Partial Pressure of CO for Iron Oxide Reduction Reactions')

plt.legend()

plt.grid(True)

plt.show()

The problem is though - and you give no information for that - that you need the accurate thermodynamic data in order to replicate their findings. I guess that their paper contains that somewhere? With it, all of the subsequent calculus (computing the equilibrium constant etc.) will be in vain.

Best,

Igor

Dear Igor,

Please try this code: GitHub Link ( https://github.com/Priyanshu7037/Baur-Glasner-diagram-for-iron-oxide-reduction-by-CO-and-H2/blob/main/bgd.ipynb).

I am using thermodynamic data from Hea-Geoon Lee's book and also attempting to use ThermoChem to obtain the necessary data. However, the diagram still does not appear correctly.

Could you please take a look and let me know your thoughts?

Best regards,

I try to use thermodynamics data from this book.

It seems OK now. I will try to add data from other sources.

Okay perfect! So it was indeed the exact input data.