2.5 Kitchen synthesis of nanorust

Kitchen Synthesis of Nanorust

J.T. Mayo, Courtney Payne, Lauren Harrison, Cafer Yavuz, Dr. Mary McHale, Professor Vicki Colvin

Objectives

• To perform a kitchen synthesis
• To obtain functional iron oxide nanocrystals that can be used for water purification of arsenic in Third World countries by using everyday items found in any kitchen.
• To appreciate the many forms of iron and the many uses of iron oxide nanocrystals.
• To appreciate the advanced analytical instruments that are used in the continuing research of nanotechnology.
• Remember: Thinking simple saves money and lives.

Grading

Your grade will be determined according to the following:

• Pre-lab (10%)
• Lab Report Form (80%)
• TA points (10%)

Background

Arsenic can be found all over the world, but is currently a particular problem in Third World countries due to the costly nature of water purification. It is especially abundant in Bangladesh, but arsenic has also been found in the ground water of Argentina, Chile, India, Mexico, Taiwan and Thailand. Additionally, closer to home, most states in the western US have levels of arsenic concentrations of greater than 10 parts per billion (10 ppb). This was not a cause for concern until the Environmental Protection Agency (EPA) in 2006 lowered the maximum allowable level of arsenic from 50 ppb to 10 ppb. In 2001, approximately 13 million Americans were drinking water that had elevated levels of arsenic in the water. http://www.epa.gov/safewater/arsenic/index.html

Previous methods for arsenic removal have included: manganese greensand columns that have been pretreated with dilute acid, coagulation/microfiltration, iron oxide based filtration, and activated alumina. The “Arsenic Removal Using Bottom Ash” or “ARUBA” method, invented by Ashok Gadgil of the Lawrence Berkeley National Laboratory, involves coating the surface of the contaminants with bottom ash and ferric hydroxide. Bottom ash is sterile waste material from coal-fired power plants which would make the cost of remediation about 0.5 cents per kg ARUBA of which generally 4-5 grams of ARUBA is needed for 1 liter of water, initially containing 400 ppb arsenic.

Nanomagnetite synthesis for arsenic removal has been hailed as Forbes: ‘Top 5 Nanotech Breakthroughs of 2006’ and Esquire listed it as ‘Six Ideas That Will Change the World’ in 2007. Basically, the technique entails forming iron oxide nanocrystals that possess very unique and size-dependent characteristics for environmental remediation of arsenic contaminated water.