The autothermal reforming of oxymethylenether from the power-to-fuel process

Abstract

Synthetic energy carriers that are not based on crude oil or natural gas can contribute to the transcending of fossil-based sources of energy in the future. A contemporary example is the organic substance, oxymethylenether (OMEn), which consists of hydrogen, carbon, and oxygen. It is reported in the literature that OMEn suppresses the formation of harmful NOx and soot and reduces CO2 emissions during the combustion process in internal combustion engines due to its high oxygen content. For the investigation presented in this paper, the use of OMEn was transferred to the autothermal reforming (ATR) process, which is normally conducted using pure diesel fuel or kerosene in order to produce a hydrogen-rich reformate gas to operate fuel cell systems. Different mixtures of OMEn and Ultimate diesel fuel were fed into Jülich's ATR 14 at a steady state. Thereby, approved reaction conditions from former ATR diesel fuel experiments with respect to O2/C and H2O/C molar ratios (0.47 and 1.9, respectively) and temperatures of the educts were applied. It was observed that the addition of OMEn to Ultimate diesel fuel resulted in stable temperatures at characteristic positions within ATR 14 and had a positive effect on the quality of the ATR product gas (reformate). For instance, the concentration of the undesired byproducts ethene and benzene decreased from 800 ppmv to the range of roughly 230 ppmv and from some 130 ppmv to less than 40 ppmv, respectively, when the mass fraction of OMEn in the OMEn/Ultimate diesel mixture was increased from 0% to 30%.