Roe-Hoan Yoon, NAE

University Distinguished Professor
CAST Director

146 Holden Hall (0258)
445 Old Turner Street
Blacksburg VA 24061
Ph:  540-231-7056
Cell: 540-357-0189
Email: ryoon@vt.edu
Click here for CV

Dr. Yoon Receives Grant to Study Bubble–Bitumen Interactions

The fundamental study of bubble-bitumen behavior is the subject of a one year research agreement between the Canadian Oil Sands Network for Research and Development (CONRAD) and Virginia Tech Professor Roe-Hoan Yoon.

During the process of oil sand recovery, air bubbles attach to the surface of bitumen droplets and sometimes are incorporated into bitumen. This allows the bubble-bitumen aggregates to float to the top of a flotation cell, while hydrophilic particles such as sand and clay sink to the bottom, thereby achieving separation. For the bubble-bitumen interaction to occur, the thin film of water (or wetting film) between bitumen and the air bubble must thin and rupture quickly. Otherwise, the bitumen will be lost along with the gangue minerals, resulting in a low bitumen recovery. In general, wetting films can rupture only when the disjoining pressure is negative. However, it has not been possible to measure the negative disjoining pressure until Yoon developed a new method (Pan, L. et. al, J. Colloid and Interface Science, 2011, p.321-330).

Yoon will use this method for measuring the disjoining pressures in the wetting films formed on bitumen surfaces at various conditions of temperature, salt concentration, and surfactant concentration. The experimental results will give information relevant to the kinetics of film thinning and hence the kinetics of flotation, the effect of bubble size on flotation, and the surface chemistry of bitumen. By better understanding the basic science of the process improvements can be made leading to the more efficient recovery of bitumen.

CONRAD, a non-profit organization, is a network of companies, universities and government agencies organized to facilitate collaborative research in science and technology for Alberta Oil Sands.

New Technology for Coal and Mineral Recovery Licensed to Virginia Company for Commercialization

Virginia Tech Intellectual Properties, Inc., signs exclusive license agreement with Richmond-based startup, Minerals Refining Company, to exploit novel Virginia Tech separation technology

Virginia Tech Intellectual Properties, Inc. (VTIP) announces an agreement with Minerals Refining Company, LLC (MRC) to commercialize a novel process for recovering high value minerals, including coal. The patent pending invention is a novel method for separating fine mineral particles from slurry, and then removing any residual moisture from the target particles. Moisture removal is particularly important in the recovery of fine coal, potentially allowing tons of coal dust previously stored in retention ponds to be used for fuel. This makes the new process environmentally friendly because it recovers coal particles that were previously considered pollutants.

“My research group at Virginia Tech has developed many separation technologies in the past that are currently used in the minerals and coal industries worldwide,” says Dr. Roe-Hoan Yoon, Chaired Professor, Director of the Virginia Tech Center for Advanced Separation Technologies, and co-inventor of the process. “Scale-up and commercialization of a new technology requires a team work, involving motivated students, experience, and industry support. I believe that we have all of these essential elements in place for another commercial success story. I also believe that timing is good in a sense that this new technology will help the industry minimize environmental impact.”.  More

Appalachia is full of coal impoundments – places where water-soaked ultrafine coal is discarded. A key decision made by mining executives has emptied one such pond near the small town of Carbo in Southwest Virginia, and turned a whopping $50 million profit. The up-front investment, by comparison, was minimal. They paid roughly $1.5 million for the entire project, including a specific type of separation technology that enabled the recovery of the fine coal from the pond. Read more