Experimental and theoretical studies on decomposition of pyrrolidine

A laminar premixed pyrrolidine/oxygen/argon flame with volume ratio C/O/N of 1.0/2.4/0.25 at 40 mbar was investigated using molecular-beam mass spectrometry (MBMS) with tunable synchrotron vacuum ultraviolet (VUV) photoionization. About 50 species were identified from photoionization efficiency (PIE) spectra, including various air pollutants such as nitric oxide, ammonia, hydrogen cyanide, acetonitrile, formaldehyde, acetaldehyde, and propanal. Some radicals were detected including C4H8N, C4H7, C3H5, C3H3, C2H5, CHO, and CH3. Detected molecular intermediates include the isomers of C2H4O (ethenol and acetaldehyde), C3H4 (propyne and allene), C4H6 (1,3-butadiene and 1-butyne) and C4H8 (1-butene and 2-butene). Based on the experimental observations, the decomposition and ring-opening pathways of pyrrolidine were calculated at G3B3 level. Also, likely reaction channels from the products of H- and H2-elimination reactions were proposed. This combined experimental and theoretical investigation intends to shed light on the decomposition channels of pyrrolidine which may assist the development of a kinetic model for pyrrolidine pyrolysis and combustion.