(547h) Comparison of Batch Vs Continuous Operation for the Acquisition of Robust Reaction Kinetics in the Production of Succinimide Dispersants

Production of specialty chemicals to-date is conducted almost exclusively in batch or semi-batch reactors. Transition to continuous processing promises strong improvements—so-called “process intensification”—over the century-old batch processing technology with lower unit energy consumption, less waste generation, reduced exposure hazards, smaller process footprint, lower capital investment and more consistent product quality. The transition to continuous processing—already demonstrated widely at the much smaller scale of the pharmaceutical industry—thus offers the prospect of truly revolutionizing the manufacture of specialty chemicals. However, the detailed chemistry and kinetics underlying current processes are in most cases poorly understood (if not completely unknown). Transition to continuous processing hence requires collection of robust and accurate kinetics as a key prerequisite.

This work presents results from a university-industry collaboration between Lubrizol Corporation and the University of Pittsburgh, under the umbrella of the recently formed RAPID Modular Chemical Process Intensification Institute. It aims to demonstrate the transition from batch to continuous processing focused on lubricant chemistry. Specifically, we present results from a kinetic investigation into the production of succinimide dispersants via reaction of a poly-isobutylene succinimide anhydride (PIBSA) with polyamines. The molecules undergo a condensation reaction to produce a large surfactant molecule with a polar head group and a long, oil soluble polymer tail. A complete family of products (which form the largest volume oil additives) is made by varying molecular weight, structure and stoichiometric ratio of the various reactants.

Here, we present results from a detailed investigation of the reaction system in a small laboratory-scale batch reactor using online IR spectroscopy as the analytical tool. The use of a batch system has the advantage of easy experimentation and enables the acquisition of large amounts of data through measurement of long concentration time traces, thus facilitating the acquisition of robust kinetics. However, in order to cover a large parameter range (such as operating temperatures, reactant concentrations, etc) a large number of experiments is required. We therefore compare the acquisition of kinetic data from the batch system with a continuous reactor system and discuss advantages/drawbacks of each variant.