A new method to determine particle size distribution from NMR self-diffusion data is presented. The method is not subjected to the usual limitations of standard techniques, like an a priori hypothesis on the form of the distribution, or the prerequisite that suitable experimental conditions exist to enclose the whole volume fraction distribution. The new procedure, based on the measurements of free self-diffusion coefficients, was applied first by way of demonstration, to a water-in-oil emulsion system. Here, the experimental conditions were such that the data had enough information to describe the distribution function completely. Very good agreement was found for the size distribution obtained via NMR and optical microscopy data analysis. Remarkably, using the same approach in the case of a more complex oil-in-water emulsion system, for which experiments did not cover the whole range of size distribution, very good agreement was also obtained.
SIZE POLYDISPERSITY DETERMINATION IN EMULSION SYSTEMS BY FREE DIFFUSION MEASUREMENTS VIA PFG-NMR
AMBROSONE, Luigi;
2004-01-01
Abstract
A new method to determine particle size distribution from NMR self-diffusion data is presented. The method is not subjected to the usual limitations of standard techniques, like an a priori hypothesis on the form of the distribution, or the prerequisite that suitable experimental conditions exist to enclose the whole volume fraction distribution. The new procedure, based on the measurements of free self-diffusion coefficients, was applied first by way of demonstration, to a water-in-oil emulsion system. Here, the experimental conditions were such that the data had enough information to describe the distribution function completely. Very good agreement was found for the size distribution obtained via NMR and optical microscopy data analysis. Remarkably, using the same approach in the case of a more complex oil-in-water emulsion system, for which experiments did not cover the whole range of size distribution, very good agreement was also obtained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.