A Thermodynamic Approach for Simultaneous Solvent and Process Design of Continuous Reactive Crystallization with Recycling

A Workflow for Crystallization Process Design with Simultaneous Process Optimization and Solvent Selection based on the Perturbed‐Chain Statistical Associating Fluid Theory

“…An MINLP-based solvent blend design framework for crystallization processes was developed by Adjiman and co-workers [6][7][8], which was based on the statistical associating fluid theory (SAFT)-γ Mie [9] as the unified thermodynamic model. Our group [10][11][12][13][14] developed a simultaneous solvent selection and process optimization framework for crystallization-based processes based on the perturbed-chain statistical associating fluid theory (PC-SAFT) [15,16]. The applicability was demonstrated for several continuous processes involving cooling, evaporative, antisolvent or reactive crystallization steps with downstream solvent purification and recycling.…”

“…Our aim is that a user with a need to purify a certain chemical with crystallization can easily navigate the workflow without having to commit substantial resources in either extensive experimental screening or programming yet can obtain a crystallization process design with good performance. The workflow is based on the solvent selection and process optimization framework that our group previously developed [10][11][12][13][14]. The workflow considers cooling, antisolvent, and evaporative crystallization, which are the most common crystallization methods without reaction.…”

Simultaneous Solvent Selection and Process Design for Continuous Reaction–Extraction–Crystallization Systems

“…Wang and Lakerveld developed a computational approach for simultaneous solvent selection and process design for a continuous anti-solvent crystallization process with possible anti-solvent recycling after a flash separation, which was later extended to a multi-stage vapor–liquid separation and rigorous distillation design. , The latter required a hybrid optimization approach for computational tractability. Recently, their approach was extended by considering reactive crystallization and the possible recycling of solvents and reactants . Chai et al developed a grand product design model to screen or design solvents for crystallization with downstream filtration, washing, and drying.…”

“…The approach combines relaxation strategies with perturbed-chain SAFT (PC-SAFT), which is employed as the unified thermodynamic framework, to convert the original MINLP problems into nonlinear programming problems (NLPs). The approach extends our earlier work in which a similar optimization strategy was developed for continuous crystallization processes involving solvent recycle, − which was inspired by optimization approaches for processes involving CO 2 capture ,, and organic ranking cycles. − Even though equilibrium modeling and MINLP-based solvent and process optimization methods for individual unit operations are well documented, the possibility of extending state-of-the-art modeling and optimization methods to a process based on an integrated reactor–extractor–crystallizer sequence has not been explored systematically yet. The key advancements of the presented framework compared to prior work are (1) the capability to simultaneously consider chemical, liquid–liquid, solid–liquid, and vapor–liquid equilibria, (2) the use of electrolyte PC-SAFT (ePC-SAFT) as the unified thermodynamic model to account for the impact of ions, which may occur in synthetic reactions, (3) the use of multiple crystallization steps to give the flexibility to choose the optimal crystallization method and crystallizer configuration, and (4) a UNIFAC-based PC-SAFT pure component parameter estimation technique to model compounds for which little to no solubility data is available.…”

“…Recently, their approach was extended by considering reactive crystallization and the possible recycling of solvents and reactants. 26 Chai et al 27 developed a grand product design model to screen or design solvents for crystallization with downstream filtration, washing, and drying. Their model was composed of seven sub-models (i.e., property, process, quality, cost, pricing, economics, and environment) to take a variety of factors into consideration.…”