Development of New Methods for Assessing Solidification/Stabilization of Hazardous Waste Using Solid-State Nuclear Magnetic Resonance Techniques.

New methods for assessing solidification/stabilization (S/S) of hazardous waste using solid-state nuclear magnetic resonance are developed for the purpose of diagnosing on a microscopic level the performance of S/S as a hazardous waste disposal technique. There are four techniques developed and described in this dissertation: (1) Solid-state deuterium NMR spectroscopy is used to determine if a particular deuterated organic waste is effectively solidified/stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix; (2) Constant time pulsed field gradient $\sp1$H NMR spectroscopy is tested on a liquid waste encapsulated within a solidified matrix to determine if droplets of liquid waste are entrapped within a solidified matrix. It yields a size distribution image of vesicles containing fluids, and measures the diffusion rate of organic materials in solid matrices; (3) Three-dimensional NMR imaging of a hazardous waste/cement sample is tested for the determination of the pore structure connectivity pattern and the observation of waste leaching; (4) NMR hole-burning spectroscopy is attempted for the study of the microscopic motions of waste in the cement matrix. These NMR techniques give information on the microscopic waste/cement interactions while providing a nondestructive evaluation of the quality of S/S process much superior to the destructive techniques such as leaching