Open AccessThermodynamic sensitivity analysis of CO2 reforming of methane based on equilibrium predictions
Author(s) -
Alias Abdul-Rahman,
Aishah Abdul Jalil,
Tan Ji Siang,
H.U. Hambali
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/808/1/012001
Subject(s) - gibbs free energy , methane , carbon fibers , chemistry , thermodynamics , selectivity , chemical equilibrium , carbon dioxide reforming , thermodynamic equilibrium , carbon dioxide , syngas , materials science , hydrogen , organic chemistry , catalysis , physics , composite number , composite material
Thermodynamic sensitivity analysis was conducted to evaluate the selectivity dry reforming of methane (DRM) with respect to other competing side reactions in terms of Gibbs energy minimization and equilibrium reactor compositions. Spontaneity of each reaction was evaluated by their corresponding changes in Gibbs energy as a function of reactor temperature from 100 – 1000 °C. At temperatures above 700 °C, all reactions considered with the exception of the Boudouard reaction are spontaneous due to their negative deltaG values. Equilibrium compositions were computed for 40 kmol of feed (CO 2 + CH 4 ) to determine its sensitivity to occurrence of reverse water-gas-shift (RWGS) reaction and changes in feed CO 2 /CH 4 ratio. The presence of RWGS reaction results to higher reactant conversion accompanied by more severe carbon formation. The H 2 /CO ratio was however not affected by its occurrence. At CO 2 /CH 4 feed ratio of 2, the product ratio was barely affected and at minimal carbon formation while CO 2 /CH 4 ratio value of 0.5 produced a lot of carbon especially at high temperatures due to the prevalence of CH 4 cracking. DRM is thus more preferable at temperatures above 700 °C, devoid of RWGS and high feed CH 4 .