SusChEM/EAGER: Novel Glass and Glass-Ceramics from Organic Waste

Colorado School Of Mines, Golden CO

Investigators

Abstract

NON-TECHNICAL DESCRIPTION: A recent discovery at the Colorado Center for Advanced Ceramics in the Department of Metallurgical and Materials Engineering has demonstrated that commercial and new multicomponent glass can be made entirely from food or agricultural wastes with promising physical and chemical properties. This represents one of the first demonstrations of making glasses and glass-ceramics from unusual and sustainable mineral sources. The global production of new glass (excluding recycled cullet (recycled broken or waste glass)) is about 100 million tons, with flat glass accounting for approximately 55 million of these metric tons. Flat glass is typically ~70 wt.% silica, and so using these figures, it can be calculated that 36.4 million metric tons of silica is needed to satisfy the global demand. Concurrently one can consider the worldwide production of the main three grains consumed by humans in 2011 was 2,173 million tons worldwide. These grains (of rice, wheat, and corn) produce waste in the form of husks, stems, and cobs, and they are about one fifth of the total production by weight. This figure amounts to about 435 million tons of waste, which will on average be 15% silica. Therefore, using these figures, 65 million tons of silica could have been harvested from these three waste streams alone. This project will explore the feasibility of using these organic waste streams to make glass. TECHNICAL DETAILS: The research project addresses the following objectives: 1) understanding the physical and chemical properties of these novel glasses, 2) examining the advantages, if any, these glasses have over those produced with mined minerals, and 3) expanding this approach to other material systems such as glass-ceramics and ceramics. A post-doctoral associate is working closely with Dr. Cornejo in each of the steps. Initially, they are creating a catalog of minerals suitable for glass formation from food/agricultural waste. From suitable precursor materials, glasses that are chemically identical to commercial glasses are being synthesized. The resulting surface properties are being characterized using techniques such as X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Nuclear magnetic resonance (NMR) and confocal Raman microscopy are being used to ascertain the structure and chemistry of both bulk and surfaces. Finally, the optical, chemical, and mechanical properties of these glasses are being compared to existing commercial glasses of the same chemical composition to establish potential differences and similarities.