Facile evaluation of the crystallization of nano-ZSM-5 using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and multivariate curve resolution-alternating least squares

Abstract

Nano-crystal ZSM-5 was fabricated through the reflux crystallization method under atmospheric pressure and the crystallization evolutionary process was investigated utilizing Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy. The control of the crystallization process and understanding of the growth mechanism of nano-crystals are considerable in developing technological applications. The aim was to compare the outcome of the proposed approach as an alternative with that of XRD. Multivariate curve resolution-alternating least squares (MCR-ALS) was employed to resolve the DRIFT spectral data set providing the evolution trend of the crystallization process using Evolving Factor Analysis (EFA) as an initial estimate approach of concentration profiles. The non-parametric Wilcoxon signed rank test (t-test) was applied to evaluate the obtained results which confirmed the reasonable agreement between two methods.