The almost-magical properties of a common substance: Iron
Some of the most important products in our lives are typically made by applying expensive elements in the periodic table. Synthetic chemistry—the process that makes everything from plastics to pharmaceuticals—relies on these rare molecules to activate the chemical bond necessary to produce these goods.
Virender K. Sharma, PhD, professor at the Texas A&M Health Science Center School of Public Health, thinks he’s discovered a better way. He specializes in environmental chemistry, and his particular passion is ferrate, a type of “supercharged” iron—iron that has lost four or more of its electrons. Instead of using elements like gold or palladium, manufacturers could use iron, which is one of the most abundant elements on the planet—and correspondingly inexpensive. It would also generate far less waste, making ferrate-based manufacturing relatively environmentally friendly.
“When you synthesize any organic molecules for industry, carbon-hydrogen bonds need to be activated,” Sharma said. “Gold and palladium both activate this bond, but these are both very expensive—palladium is about $15 per gram—and of a limited supply, so we need to go with simple molecules like iron, and we have breakthrough research in order to figure out how to make ferrate do the same thing.” To compare, iron costs only about .02 cents per gram.
This technology has recently been awarded a patent.
SEE ALSO: Water purifying device for military
Although ferrate is great for creating things like pharmaceuticals, it’s useful for cleaning them up as well. It is able to transform pharmaceuticals into non-toxic molecules, as Sharma and his collaborators published in a paper in ACS Sustainable Chemistry & Engineering. This is especially important as many drugs, like common antibiotics, are often flushed into in our water supply. Ferrate is able to turn these antibiotics into inert molecules, which should help combat the problem of antibiotic resistance by leaving fewer active antibiotics in the environment.
“Water pollution is a serious problem in China, so when I saw that Dr. Sharma did a lot of this kind of research, I really wanted to work with him,” said Long Chen, a Texas A&M public health PhD student from China and a co-author of the paper. “Ferrate is a very novel technology to treat water, and I’ve been learning so much in Dr. Sharma’s lab.”
Ferrate cleans more than just pharmaceuticals from water. Much of Sharma’s previous work has focused on using environmentally friendly ferrate to remove a wide range of contaminants—from antibiotics and estrogens to pesticides and toxic metals—from water. “Naturally occurring iron can be easily converted to ferrate, which can be used in both air and water purification as a disinfectant to aid in the inactivation of viruses, bacteria and toxins in a matter of minutes, without leaving behind harmful by-products,” Sharma said. “You just make a ‘tea bag’ out of this molecule and put it in the water, and then you can drink the water.”
This work has a number of applications, including providing a reliable source of purified drinking water for the U.S. military. “I’m really excited about this molecule,” Sharma said. “I’ve been working on ferrate for 26 years, and I’m still fascinated by it.”
Sharma, who was recently asked to serve as guest editor of two international journals (ACS Sustainable Chemistry and Engineering and Journal of Hazardous Materials) for their special issues on green chemistry and remediation of contaminants in water, also takes time to mentor the next generation of environmental chemists from around the world.
“I was following Dr. Sharma’s work through journals,” said Jashanpreet Singh, PhD, a postdoctoral fellow from India in Sharma’s lab. “I am honored to have the opportunity to work with him, and I have learned a lot here at Texas A&M.”
Lately, Sharma’s focus has also shifted to formation of natural nanoparticles. Nanoparticles are tiny—from one to 100 nanometers, and a nanometer is one billionth of a meter. His research has found that natural inorganic nanoparticles do exist in the environment like air, rivers, lakes, bays and wastewater. “The input of metal pollution to a coastal environment like Galveston Bay would result in the formation of nanoparticles by interacting with components present in the natural waters,” Sharma said. These nanoparticles enter into the ecological system and may impact aquatic organisms. “There’s concern about these nanoparticles and their effect on human health and environmental health, but we really don’t know the effect of these naturally occurring particles.”