Rendering toxic metal oxides inert
Leonard, Joe (2009). Rendering Toxic Metal Oxides Inert. In Proceedings: 5th Annual Symposium: Graduate Research and Scholarly Projects. Wichita, KS: Wichita State University, p. 134-135
Ceramic glazes are composed of three primary components: a flux, an alumina- bonding agent, and a glass former. These three materials can be adjusted for firing ranges as low as 1213 degrees Fahrenheit, up to 2419 degrees Fahrenheit. However, some of the oxides used are toxic, and can leach through the glaze matrix rendering them unsuitable for functional ware. One oxide is Copper Oxide, applicable in different forms: Carbonate-CuCo3, Cupric Oxide- CuO, and Sulfate-CuSO4 5H20. All three are toxic, and have been found in previous studies to leach to the surface of a glaze that contains more than 5% Copper Oxide by weight. When acidic liquids such as citric juices, vinegar, or wine come into contact with these surfaces, mild poisons are created. While these materials can create a beautiful array of colors, food safe glaze surfaces are very important to a contemporary ceramicist working in the vein of functional dinner ware. Approaching the composition of the glazes in a line blend series-where each material is incrementally adjusted in percentages of 5%- information has been obtained about the necessity of the proportions of each material present in the published glazes, arriving closer to an inert surface suitable for ceramic ware production.
Paper presented to the 5th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Hughes Metropolitan Complex, Wichita State University, May 1, 2009.
Research completed at the School of Art & Design, College of Fine Arts