This award supports a joint research project between Dr. Kevin Powers, Particles Engineering Research Center (PERC), University of Florida, Gainesville, Florida and Dr. Suzan Ibrahim, Central Metallurgical Research and Development Institute, Helwan, Egypt. They plan to conduct studies involving the beneficiation, characterization and evaluation of two grades (one high grade and on low grade) of North African deposits of diatomaceous earth, a sedimentary deposit made up of amorphous hydrous silica cell walls of dead diatoms with desirable characteristics of low density, high porosity, and high surface area. These characteristics coupled with their inertness, abrasiveness and other characteristics make them extremely valuable in diverse industrial and domestic applications. The Egyptian team will focus on the beneficiation of the ore material. The U.S. team will be in evaluating the effectiveness and quality of the beneficiated material through particle characterization, permeability testing, electron microscopy and other testing.
Scope: Diatomaceous earth or diatomite is fine-grained siliceous sedimentary rock consisting primarily of amorphous opaline silica with minor amounts of organic residue, secondary minerals, as well as co-deposited non-diatomaceous or crystalline clastic debris. Generally, for high-grade ores, gentle crushing is applied, followed by drying, and milling in certain mills to avoid ore destruction. Ores of low-grade have to be wet processed to remove the accompanied contaminants. Physical properties of processed diatomite that provide unique commercial value in a broad spectrum of market end-uses include ornate fine structure, low bulk density, and high porosity and surface area. Other properties are mild abrasiveness, high absorptive capacity, insulating ability, relative inertness, and high brightness. End-use markets are diverse and range from insulating brick and absorbents through quality sensitive filter aids and premium quality functional fillers. New significant uses include purification of plasmid DNA, high performance adsorbents. This is an economically important mineral in both the United States and Egypt. The research under this proposal will provide better understanding of the beneficiation processes and the characteristics of the resulting products. The research results will be disseminated in both countries via publications and within the PERC by seminars and participation of undergraduate students associated with the two institutions.