Thermodynamic Analysis of Methanol Synthesis

Abstract

In this research, the synthesis reactions of such promising e-fuel as methanol by hydrogenation of syngas were studied using methods of chemical thermodynamics. The standard enthalpy and entropy of the starting reagents (CO2 , CO, and H2 ) and products (CH3 OH, and H2 O) of the reactions were found. Using these thermodynamic characteristics, the enthalpy (∆r H), entropy (∆r S), and Gibbs potential (∆r G) of the hydrogenation reactions were determined. It was established that the hydrogenation of carbon dioxide at temperatures above 473 K may create a problem since high pressures above 20 MPa are required to implement this reaction. On the other hand, the hydrogenation reaction of carbon monoxide at temperatures above 473 K can be carried out even under moderate pressures. Since the presence of carbon dioxide in the synthesis gas is a negatory factor hindering methanol synthesis, it is desirable to use synthesis gas pre-purified from carbon dioxide. As a result, the following optimal conditions for the synthesis of methanol from syngas consisting of carbon monoxide and hydrogen were proposed, T = 483-503 K, P = 2-3 MPa