Population Balance Modeling of the Solution‐Mediated Transformation of DL‐Methionine Polymorphs

Abstract

Experimental measurements of the solution‐mediated transformation (SMT) of the metastable polymorph of DL‐methionine (α‐DL‐met) into the stable polymorph (γ‐DL‐met) in water were performed at 25 °C. These results were compared to models of the crystallization and the SMT of α‐DL‐met into γ‐DL‐met that were developed using the concept of the population balance equation (PBE) applied to both of the polymorphs. The growth, dissolution, and nucleation kinetic expressions obtained in a previous work were used in the models. It was found that the PBE models did not satisfactorily describe the SMT process of DL‐met when the measured crystallization and dissolution kinetics were used. There were large mismatches between the simulation and the experimental results. Modifying the model of the dissolution kinetics of α‐DL‐met enabled these mismatches to be lowered. The results showed that the SMT of DL‐met is controlled by the rate of dissolution of α‐DL‐met.

Growth and Dissolution Kinetics of A and B Polymorphs of L‐Histidine

“…In literature, a lot of studies demonstrate that the growth of the stable polymorph is the limiting step, e.g., L ‐glutamic acid 22–25, taltireline 26, and carbamazepine 5, 27. The SMT of DL ‐methionine 6 and glycine 28 are at least two examples where the dissolution of the metastable polymorph was the limiting step.…”

“…Polymorphic crystallizations consist of the competitive nucleation and crystal growth of the polymorphs and the transformation from the metastable polymorph to the stable polymorph, usually via a solution‐mediated transformation (SMT) mechanism. This involves nucleation and crystal growth of the stable polymorph and dissolution of the metastable polymorph 3–6. Therefore, the mechanism and kinetics of each elementary step in the crystallization process needs to be understood to predict and control the formation of the appropriate polymorph.…”

“…Accurate modeling of the SMT can be performed by creating separate models of each of the mechanisms involved and combining these models within the framework of the population balance equation (PBE) 6–8, which is a two‐step method. Firstly, the rates of the crystallization processes, i.e., nucleation and growth, and the rate of dissolution of each polymorph are obtained through specific experiments.…”

Transition Metal (Mn, Fe, Co, Ni)‐Doped Graphene Hybrids for Electrocatalysis

“…In general, a metastable polymorph crystallizes first and tends to transform into a more stable one 6. The transformation process usually occurs through interactions with a solution phase and is called solution‐mediated polymorphic transformation (SMPT) 7, 8.…”

Systematic model identification and optimization-based active polymorphic control of crystallization processes

“…The functions used to express the nucleation rates for both the stable and metastable forms of L-glutamic acid were different in the mentioned studies: Cornel at al. (2009) and Sheikoleslamzadeh and Rohani The solution-mediated transformation of DL-methionine polymorphs was modelled by Wantha and Flood (2013) (Trifkovic et al 2012). Such model was solved using the methods of moments.…”