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Carnegie Mellon’s Institute for Green Oxidation Chemistry

Problem: Oxidation is a fundamental process in many industrial sectors, but this process often relies upon chemicals and can result in the production of hazardous substances. How might we cause necessary processes of oxidation in a manner that is safe for our environment?

Solution: Through the activation of hydrogen peroxide.

Most of us are familiar with the reaction that occurs when a drop of hydrogen peroxide is placed on the skin. The bubbling we see is the result of oxidation, a process in which oxygen atoms (here stripped out of the peroxide by metal ions in the skin) react with other substances. The use of hydrogen peroxide to cause oxidation is not limited to our placing a drop of peroxide on the skin: in the human body liver enzymes routinely use hydrogen peroxide to destroy toxins in the blood.

Following the example of nature, chemist Terry Collins of Carnegie Mellon’s Institute for Green Oxidation Chemistry (the Institute) has developed methods through which hydrogen peroxide might be used as an environmentally friendly cause of oxidation. Collins and his research team have developed catalysts (substances that help chemical reactions occur) known as TetraAmindoMacrocyclicLigand, or TAML, activators. These catalysts activate hydrogen peroxide and focus chemical reactions on certain targets. The result is “green chemistry”, chemical processes that mimic the workings of nature and are safe for the environment.

One obvious candidate for Collins’ method has been the pulp and paper industry. In order to make white paper, the pulp and paper industry has typically relied upon chlorine dioxide to instigate the processes of oxidation that result in bleaching. The problem is that chlorine-based bleaches produce dioxins that contaminate water supplies; in addition, these effluents stain natural waterways and reduce the flow of light to aquatic ecosystems. An alternative, environmentally friendly solution is provided by Collins’ TAML activators. These one-time-use small molecule catalysts serve to improve peroxide pulp bleaching. This alternative method works at normal temperatures and pressures, is not corrosive, and requires no special handling. It is also cheaper than other proposed alternatives to chlorine dioxide use; for example, Collins’ method costs one-tenth what oxygen-based bleaching processes might cost to implement.

The Institute for Green Oxidation Chemistry is looking for other ways that TAML activated hydrogen peroxide might be of use. They are developing the use of TAML activators for laundry science, surface cleaning, and toxic chemical destruction and decontamination. Of particular interest to those at the Institute is the possible use of TAML activated hydrogen peroxide for destroying chemical pollutants in water. Safe, low cost water disinfection and detoxification technologies are crucial for the well being of those in developing countries, and providing such technologies is the “single most important…long-term goal of the Institute”.

Contact Group: Terry Collins

The Institute for Green Oxidation Chemistry

Department of Chemistry
Carnegie Mellon University
4400 Fifth Avenue
Pittsburgh, PA 15213

Phone: 412-268-6335

Email: tclu@andrew.cmu.edu

Web site: www.chem.cmu.edu/groups/Collins/