More than 136 million tons of coal ash waste materials are being produced to meet the electricity needs of the US each year. However, more than 55% of these wastes are being dumped in the landfills and ash ponds. Many studies indicate the presence of a variety of metal oxides such as Iron, Aluminum and Titanium in these wastes. Another application envisioned is to make cement-less concrete using these materials to reduce the Portland cement consumption which is responsible for 5-8% of total CO2 emissions as a greenhouse gas.

The main objective of this study was to develop a novel flowsheet for extracting valuable metal oxides from coal ash wastes and to develop a suitable process to utilize them as a useful product in the form of a cement-less concrete. We used totally waste materials to produce some useful metals and also cement-less concrete with much less carbon footprint. We not only left nothing behind as waste but also helped the climate and prevented global warming by decreasing carbon dioxide production.