PUB - Publikationen an der Universität Bielefeld

Oxymethylene ethers (OMEs) are potential alternative fuels that can be produced in a sustainable way based on CO 2 and electricity. Additionally, they exhibit low tendencies to emit NO x or soot during practical combustion. Dimethoxy methane (DMM, CH 3 OCH 2 OCH 3 ) has received increasing attention as the smallest OME with a O-CH 2 -O moiety. In the face of a possible application in exhaust gas recirculation (EGR) scenarios, understanding the influence of NO x on DMM oxidation is of importance. In this work, eleven mixtures of DMM/NO/O 2 /Ar were investigated in an atmospheric laminar flow reactor employing an extensive set of diagnostics. Molecular-beam mass spectrometry (MBMS), Fourier-transform infrared (FTIR) spectroscopy, NO x chemiluminescence detection, and double imaging photoelectron photoion coincidence (i 2 PEPICO) spectroscopy were combined to obtain a reliable speciation. All in all, species concentrations from different instruments showed a good agreement and one technique could counterbalance the physical limitations of another technique in many cases. In this manner, accurate mole fraction profiles of intermediates like e.g. CH 4 , C 2 H 4 , NO 2 , and methyl formate (C 2 H 4 O 2 ) were gained. Based on i 2 PEPICO results, nitromethane (CH 3 NO 2 ) and trans -HONO could additionally be identified as crucial intermediates in the NO-assisted oxidation of DMM. The present data set therefore provides an excellent basis to enhance future model development.