Scaling-up Aldol Condensation Reaction in Flow Reactor for Branched Bio-Lubricant Base Oil Production


  • Mahdi Al Ismail, Chemical Engineering, University of Delaware

Faculty Mentor(s)

  • Tejas Goculdas, Chemical and Biomolecular Engineering, University of Delaware
  • Sunitha Sadula, Chemical and Biomolecular Engineering, University of Delaware


The production of renewable lubricant base oils has garnered substantial attention due to their potential to mitigate environmental challenges posed by petroleum-derived feedstocks. Our group recently demonstrated a two-step synthesis for renewable base oils starting from 12-tricosanone and furfural. Shifting the first step of this synthesis yielding C28 and C33 intermediates (done through aldol condensation) to a flow reactor is desirable due to its favorable economics compared to the batch scale. Therefore, this research project focused on operating a plug flow reactor to facilitate the aldol condensation (AC) reaction. Following a framework adapted from Norton et al., the AC reaction was replicated to gain a comprehensive understanding of the reaction and its products. The design of the flow reactor was meticulously planned, and all necessary components were assembled, including tubing fittings, heating, and reactor coils. Throughout the experimentation process, overcoming obstacles lead to crucial modifications in the flow reactor design. Introducing Furfural/methanol into the system through the HPLC pump and loading the heated syringe pump with the 12-tricosanone/sodium hydroxide/methanol solution demonstrated noteworthy improvements in system efficiency. After observing low yields of C33 furan, the system was adjusted to introduce fresh furfural between the reaction coils to produce an equilibrium shift towards the desired heavier products. Additionally, increasing the residence time by incorporating more reactor coils and increasing the temperature resulted in encouraging yield data. Residence time was observed to be the most significant factor in producing more C33 product. The implications of this research project are promising, as the successful production of C28 and C33 furan intermediates with the flow reactor showcases the feasibility of large-scale production of renewable lubricant base oils. The findings from this study contribute valuable insights into the impact of relative reactant concentrations and residence time that can be used for future scale-up studies.