Mannschott, Thomas, Krumme, Markus, Zettl, Manuel, Kreimer, Manuel, Aigner, Isabella, van der Wel, Peter and Khinast, Johannes G. (2020) Runtime Maximization of Continuous Precipitation in an Ultrasonic Process Chamber. Organic Process Research & Development, 24 (4). pp. 508-519. ISSN 1083-61601520-586X

Abstract

The goal of this investigation was to develop a continuous process in order to produce as much material on dry basis as possible, at stable conditions, in a harsh, precipitating environment. Therefore a novel approach, the direct application of ultrasound (US) in the process chamber, was used to prolong the process time. The main focus was to avoid fouling and build-up, which is an undesired effect in continuous manufacturing. Fouling can occur for many reasons and has several mechanisms (precipitation fouling, particulate fouling, biofouling, corrosion fouling, chemical reaction fouling etc.). In the worst case, fouling can lead to a complete shutdown due to equipment blocking. In this work, two model substance combinations were used (lactose/water/isopropanol and ibuprofen/ethanol/water). A feed suspension was mixed with an anti-solvent in an ultrasonic process chamber, which transduces the power directly into the mixture. The feed suspension is composed of solids distributed in a saturated liquid, which was saturated with the respective solid. The solids are precipitated during mixing, and blockage of the system can take place due to introduced fouling and accumulation in the system. Critical process parameters (the product temperature, the US input and the solid loading) were analyzed in terms of their influence on the process stability and duration. Since this process could also be applied to produce or purify particles, the particle size distribution (PSD) of the two substances was evaluated with regard to agglomeration and attrition.

Item Type:	Article
Date Deposited:	16 Jan 2021 00:45
Last Modified:	16 Jan 2021 00:45
URI:	https://oak.novartis.com/id/eprint/38801