US Patent Number
A process for producing enhanced quality adsorbent carbons and environmentally acceptable materials for energy production from coal includes an initial step of physically cleaning the coal to remove organic sulfur and mineral tailings. Next, a coal slurry of feedstock and water is prepared. Phosphoric acid is then mixed into the water of the coal slurry to provide by volume 15-85% and more preferably 50-85% phosphoric acid. The slurry is then heated and held in a temperature range between 85° and 230° C. for a period of at least five minutes to allow the phosphoric acid to penetrate deeply into the coal. Then the coal slurry is carbonized at a temperature of between 200°-700° C. for at least five to sixty minutes. The processing produces unique products including a low ash content, low sulfur content carbon solid, a tar with a sulfur content of less than 0.05% of the original feedstock and a gas product having a hydrogen to methane ratio of at least 4:1.
University of Kentucky Research Foundation, Lexington, Ky.
Stencel, John M. and Derbyshire, Francis J., "Process for Removing Sulfur and Producing Enhanced Quality and Environmentally Acceptable Products for Energy Production from Coal" (1993). Center for Applied Energy Research Faculty Patents. Paper 33.