Formulation of the excess absorption in infrared spectra by numerical decomposition for effective process monitoring. (8th May 2018)

• Record Type: Journal Article
• Authors: Shibayama, Shojiro; Kaneko, Hiromasa; Funatsu, Kimito
• Is Part Of: Computers & chemical engineering. Volume 113(2018)
• Page Start: 86
• Page End: 97
• Publication Date: 2018-05-08
• Subjects: Process analytical technology -- Calibration-minimum method -- Online process monitoring -- Concentration prediction -- Infrared spectroscopy -- Multivariate curve resolution; Chemical engineering -- Data processing -- Periodicals; 660.0285
• DOI: 10.1016/j.compchemeng.2018.01.025
• Languages: English
• ISSNs: 0098-1354

Abstract

Highlights: We propose a novel prediction method using infrared spectroscopy. The method is able to predict concentrations with only a few calibration samples. Effects of molecular interactions on infrared spectra are considered as functions. The developed method provides accurate predictions for two liquid mixtures. Abstract: Iterative optimization technology (IOT), a method that predicts the component composition from only the infrared (IR) spectra of the pure components and mixtures by using Beer's law, has been proposed to reduce the number of calibration samples for process analytical technology in the pharmaceutical industry. However, IOT cannot be applied to mixtures that have wavelength regions where Beer's law does not hold, such as liquid mixtures. The objective of this study is to apply IOT to liquid mixtures to realize a calibration-minimum method. We propose a novel calibration-minimum method that formulates spectral changes by polynomials of the mole fractions considering reasonable boundary conditions for online monitoring. The prediction ability of the proposed method was verified by three case studies: two binary mixtures and one ternary mixture. The model selection strategy, conditions for calibration, and estimation of missing pure component spectra are also discussed. This research represents a step towards advanced calibration-minimum methods.