NMR in Industrial Process Control and Quality Control

Abstract

NMR is well suited to a variety of process control (PC) and quality control (QC) applications, although there are few examples of the former in the literature. Both high-resolution and low-resolution approaches have been used for PC/QC NMR applications; the latter dominate in popularity for a variety of practical reasons and are usually based on low-field magnets that are not capable of high-resolution performance. The most common type of low-field, low-resolution PC/QC NMR applications are based on time-domain behavior, utilizing a suitable analysis of the free induction decay or echoes in order to separate responses from components with different T2 characteristics. The most popular types of PC/QC NMR applications have been in the food processing/agriculture area, e.g., determining fat, water, or oil contents of food materials or products. Applications in the chemical industry include characterizing polymers according to a variety of characteristics (e.g., crystallinity, viscosity, extent of polymerization) that can be correlated empirically with NMR characteristics. The range of applications is growing, and one can expect dramatic growth in this area during the next few years.