Techno-economic analysis of hydrogen production from dehydrogenation and steam reforming of ethanol for carbon dioxide conversion to methanol

摘要

Decreasing carbon dioxide (CO2) emission by converting to higher-valued product has become of interest. Hydrogen (H-2) is an important feedstock required in thermochemical conversion of CO2 to chemicals such as methanol. The cost and availability of H-2 affect the cost of CO2 conversion. This study is focused on the process simulation of H-2 production from ethanol feedstock. Steam reforming of ethanol is compared with dehydrogenation of ethanol to H-2 with valued products including ethyl acetate and acetaldehyde. Form this study, steam reforming of ethanol presents the lowest cost of H-2 production at 1.58 USD/kg H-2 while dehydrogenation of ethanol presents the cost at 3.24 and 1.97 USD/kg H-2, respectively. Although presenting the lowest cost, steam reforming of ethanol provides a net positive CO2 emission in the overall CO2 conversion to methanol process. In contrast, ethanol dehydrogenation to H-2 and byproducts, ethyl acetate and acetaldehyde, promotes a net negative CO2 emission of -819.20 kg/ton methanol and -5.42 kg/ton methanol, respectively. The results present a decreasing CO2 emission with an increasing cost of H-2 production. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.