Effect of Ammonia/Nitroxyl on Hydrogen Enhancement in Dry Reforming of Ethanol: A Thermodynamic Analysis

Dry reforming of ethanol is of importace from the environmental point of view. This process can produce proper amounts of synthesis gas and leads to conversion of CO2 as a greenhouse gas to H2 and CO. In the present paper, thermodynamic analysis of this process was conducted by using Gibbs free energy minimization method and SRK EOS. By applying the Lagrange multipliers to nonlinear algebraic equations, the numerical analysis was conducted in the MATLAB environment. Besides pure ethanol, the effect of addition of ammonia or nitroxyl to the feed (e.g. three cases including pure ethanol, ethanol-ammonia, ethanol-nitroxyl) as well as temperature varying between 300-1200K was studied with respect to products distribution. The results showed that the use of additives (ammonia or nitroxyl) enhances hydrogen production over a wide range of temperature as compared to pure ethanol (at temperatures between 0-800K for the nitroxyl case and 0-1000K for the ammonia case). Furthermore, the increase of temperature led to augmentation of hydrogen moles in all cases. Comparing to pure ethanol, the highest ammonia to ethanol ratio (4:1) resulted in a threefold increase in H2 production.

Keywords:

Hydrogen , Ethanol dry reforming , Thermodynamic equilibrium , Analysis