The present invention relates to process intensification, and renewable processing routes for polymer production, for example the solar production of Nylon 6,6 and precursors relevant for the Nylon 6,6 production (such as hydrogen, adiponitrile and hexanediamine). The invention deals with the integration of solar energy into the process, specifically aims at petrochemical-free processing, and deals with reformulation of traditional (linear) processes into circular (closed cycle) processing approaches and sustainable processes.