Process monitoring of zeolite crystallization: Bridging in situ Raman spectroscopy, ex situ XRD, and predictive machine learning models

Key Points

• The aim is to monitor zeolite crystallization processes using advanced spectroscopic and machine learning techniques.
• In situ Raman spectroscopy for real-time monitoring of interzeolite conversion.
• Ex situ X-ray diffraction (XRD) for quantitative phase analysis.
• Non-negative least squares (NNLS) analysis to extract zeolite evolution from Raman data.
• Raman-based phase fractions correlate significantly with ex situ XRD quantification.
• NNLS analysis successfully captures the evolution of FAU/GIS zeolite frameworks.
• Density functional theory (DFT) modeling provides insights into framework-specific Raman signatures.