Extension of the Delplot Analysis for Experiments with Non-zero Initial Product Concentrations

The Delplot technique for the classification of experimentally derived reaction products as primary, secondary, tertiary, etc. was extended to address experiments in which reaction products are present in non-zero concentrations in the feed. This allows use of the Delplot method for the complex feedstocks common in energy applications, such as crude oil, where lumped models containing boiling-point-defined pseudocomponents will frequently have non-zero product amounts in the experimental feedstocks. We found that the existence of the intermediate products in the feed changes the behavior of the Delplots. For example, in the A →k1 B →k3 C; A →k2 D sequence with B₀ ≈ 0, the Delplot can suggest B to be primary, secondary, or neither depending upon the ratios k₁/k₂ and A₀/B₀. These findings suggest key additional experiments covering different limits to be able to identify the proper classification of the intermediate products in the reaction network.