In the European chemical industry, there is a strong drive to shift to renewable and alternative

feedstocks in the pursuit of sustainability and increased profitability. However, these feeds contain

heteroatomic compounds that are not typically present in classical fossil feedstocks and create a

big concern even when they are just considered as drop in alternative. Specifically for steam

cracking very global feed specifications are kept in place, because there is little known about the

pyrolysis reactions of these heteroatomic compounds (S, N, O) and how their decomposition is

affected by the changing hydrocarbon matrix under steam cracking conditions. Therefore in this

project the fundamental understanding of the thermochemical reactions of oxygen, nitrogen and

sulfur containing compounds will be drastically improved. To realize this objective, experimental,

theoretical and kinetic modelling work will be combined starting from an extensive investigation of

selected compounds, i.e. the reaction engineering methodology. The approach will be validated

using a unique set of existing and newly acquired experimental data. Having a mathematical model

that is able to describe the influence of the process parameters and different amounts of

heteroatomic compounds in complex hydrocarbon mixtures, on the product quality and

composition is essential for the future development and integration of renewable and alternative

process streams.