Ethanol Processor Design for Hydrogen Production. Kinetic Analysis and Process Integration

A kinetic study of ethanol steam reforming was conducted with a commercial nickel-based catalyst. The reaction was studied at atmospheric pressure, with temperatures varying from 550 to 650 degrees C and residence times up to 25 h.g/Nm(3). From the analysis of the product distribution, a scheme of reactions was proposed and used to simulate a pseudohomogeneous reactor and to fit the kinetic parameters. Results showed good fitting with the measured data. The kinetic expressions were profited toward the design of an integrated process of H-2 production from ethanol, which includes a parallel-plate reactor, a shell-and-tube membrane unit, and auxiliary units. Results showed satisfactory thermal integration with efficiencies from 43 to 47% based on lower heating values and from 52 to 57% based on higher heating values. For three different simulation scenarios, outlet streams of about 10 mol(H2)/h were obtained. The proposed scheme showed robustness, accepting-significant vartations in the set conditions and still maintaining the process operability.