Olefin profile prediction of naphtha pyrolysis using a feeding-independent continuous lumping method with mechanism analysis

• A continuous lumping analysis method on mechanism-level to reveal the intrinsic reaction process by its initial feeding structure and parameters such as temperature and pressure.
• Analyzation of naphtha composition by the PY (pyrolyzer)–GC (gas chromatograph)–MS (mass spectrometer) analysis method for parameter acquisition of this new continuous lumping method.
• New pyrolysis distribution profile based on this new mechanism-level continuous lumping method.

By avoiding the massive calculations of complicated reaction networks, the continuous lumping method has been welcomed as a means of describing hydrocarbon pyrolysis processes. In our work, with the introduction of a new distribution function representing different structure effects on kinetic parameters, a mechanism-oriented continuous lumping model is proposed to acquire the olefin profile of naphtha pyrolysis with experimentation independent of different feeding compositions. Meanwhile, micro-reactor pyrolysis experiments are conducted to analyze the structure mechanism and to obtain the pyrolysis parameters. The analytical results indicate that long-chain molecules with higher degrees of branching react faster, and long-chain alkanes with fewer side chains are more inclined to form ethylene product. The prediction results of the simulation method are consistent with the experimental results. The prediction performance is comparatively accurate and independent of feeding.