Chair:

Dr. Götz Veser

Department of Chemical and Petroleum Engineering, University of Pittsburgh

 Dr. Robert M. Enick

Department of Chemical and Petroleum Engineering, University of Pittsburgh

 Dr. Sachin Velankar

Department of Chemical and Petroleum Engineering, University of Pittsburgh

Dr. Vikas Khanna

Department of Civil and Environmental Engineering, University of Pittsburgh

Dr. Nico Proust

Dispersants Research and Development, The Lubrizol Corporation   

Title: Process Intensification Via Batch-to-Continuous Transition in the Production of Specialty Chemicals

Abstract:

Production of specialty chemicals to-date is conducted in simple, but inefficient large-volume batch reactors. However, this industry is facing challenges due to supply chain limitations, strict environmental regulations, safety concerns, and increasing costs. The pharmaceutical industry has demonstrated recently that such challenges can be overcome by transitioning from batch to modular continuous processing. The present work aimed to be a first-of-its-kind demonstration of the transition from large-volume batch reactors to smaller, modular continuous units for the specialty chemicals industry. The study demonstrates these advantages using two types of dispersants processes – production of succinate ester and succinimide dispersants – as models.

Our work demonstrates the viability of the batch-to-continuous transition for dispersants production and identifies how operational differences between batch and continuous processing can affect even the underlying reaction kinetics. We find that the presence of water as a reaction by-product during the continuous production of succinimide dispersants rendered the reaction incomplete due to thermodynamic equilibrium limitations. While purge of the head space during batch operation removes these limitations, the continuous process requires use of a subsequent drying step via a thin film evaporator (TFE). We then demonstrate further intensification of the continuous process by utilizing the TFE as a stand-alone, reactive separator which combines reaction and water separation into a single unit and thus further reduces the number of processing steps and the physical footprint of the process. As part of these studies, we furthermore developed a simplified, computationally highly efficient approach to capture the effect of mixing on reaction in a one-dimensional plug flow reactor model and demonstrated how straightforward user-accessible modifications of an infrared spectrometer flow cell can vastly improve the continuous in-situ monitoring of high viscosity reactive flows. Overall, this work developed and successfully demonstrated a systematic methodology for process intensification via batch-to-continuous transition in the production of specialty chemicals.