Multiphysics models for layer melt crystallization: Spatiotemporal evolution of temperature and impurity distributions

Layer melt crystallization (LMC) is a promising green separation technology for ultrahigh‐purity chemical production, particularly for challenging isomeric mixtures. This work develops an experimentally validated semi‐analytical framework for static LMC, integrating spatiotemporal temperature modeling, heat‐flux decomposition, crystal growth kinetics, interfacial solute partitioning, and three‐dimensional impurity‐field simulation. Systematic experiments and simulations are performed on a 2,4‐/2,6‐dinitrochlorobenzene isomeric mixture. Latent heat dominates total heat transfer (>95%), and thermal resistance exceeds mass transfer resistance by an order of magnitude. A complementary computational fluid dynamics simulation cross‐validates the thermal predictions. Crystal growth rate follows a power‐law correlation with the interfacial temperature gradient, while the effective solute distribution coefficient decreases with growth rate due to enhanced impurity entrapment. Further, the 3D simulation of spatiotemporal impurity distribution in the melt phase reveals a pronounced interfacial enrichment effect amplified at higher supercooling. The validated models provide a quantitative foundation for static LMC design and optimization.