Students Engineer a Cleaner Environment

Two NJIT graduate students, Shuangyi Zhang (left) and Zhan Shu, are doing research to safeguard water and help improve the environment.

Creating a sustainable environment is a major focus of research at NJIT, which was named of the nation’s greenest universities by The Princeton Review.

Here, students and professors use advanced engineering and new technology to clean air, preserve natural resources, combat global warming, improve energy efficiency and purify water.

Donald Sebastian, Senior Vice President for Research & Development, oversees research at NJIT that is helping to usher in a greener America.  To cite three examples, one research professor has developed methods to desalinate seawater so that it’s drinkable.  Another professor is creating polymers to replace harmful chemicals in adhesives, paints and coatings, while a third is studying ways to make buildings more energy efficient.  In terms of teaching, NJIT offers myriad courses, certificates and programs in green issues, environmental policy and sustainability.

NJIT students, both graduates and undergraduates, work on research whose aim is to create sustainable systems that improve the environment.  More recently, some of NJIT’s top graduate students have focused on water purification and water treatment.  As it is, nearly one-third of the world’s population lives with inadequate water supplies.   And some scientists predict that what with climate change and population growth, that number will increase this century to one half of humanity. 

NJIT students are working hard to solve the world’s water woes.  What follows is a brief overview of some of the award-winning research projects that graduate students are working on. 

Susana Addo NtimRemoving Arsenic from Water

Susana Addo Ntim, a Ph.D. student in Environmental Science, uses nano-technology to remove arsenic from drinking water.  Arsenic is a toxin that in sometimes seeps into groundwater from the earth’s crust and as a result of mining, agriculture and manufacturing processes. Susana applies carbon nanotubes -- large carbon molecules that form cylindrical tubes -- to remove arsenic from water. Specifically, she identified and studied a metal-oxide nano-hybrid that proved effective in removing arsenic from water.     

Susana has published her water purification research in two journals and has presented her research findings at conferences around the nation.  Along with her research adviser, Somenath Mitra, professor of chemistry and environmental sciences, she has filed a patent to protect her research. She also won first place for graduate students in the recent 2012 Dana Knox Student Research Showcase.  This week, she successfully defended her doctoral dissertation.

'Water is the most important resource in the world, yet access to clean water in most of the world is a challenge,” says Susana. “An estimated 1.2 billion people are without safe drinking water, with millions dying annually from diseases transmitted through contaminated water. Unfortunately, the list of contaminants found in water keeps growing. It’s therefore imperative to develop new water purification techniques that will help people have clean water. That is what fueled my interest in clean water research.”

Creating Ozone Bubbles to Clean Filters

Ali Ghadimkhani, a Ph.D. student majoring in Environmental Engineering, uses an equally innovative approach to treat water. He uses ceramic membranes to create nano-sized air and ozone bubbles. And the ozone bubbles unclog the ceramic membrane water filters used in treatment plants.

Ozone commonly lasts only one hour in water.  But Ali’s technique allows ozone in water to last for more than 100 days, making it feasible to use in water treatment plants.

His research has won him two recent accolades.  He recently took first place in a research contest in Atlantic City sponsored by the American Water Works Association.  And he placed third for graduate students in the Dana Knox Student Research Showcase.

“Ali’s research is state- of-the-art and once completed will certainly have many benefits to the water industry,” says Taha Marhaba, a professor of civil and environmental engineering who advises Ali’s research.

Removing Contaminants from Water

What happens when unregulated contaminants found in prescription and over-the-counter drugs, fragrances, cosmetics and other personal consumer products seep into our water supply? What effect do these contaminants have on the water supply and what is the best way to remove them?

That’s the question that two Ph.D. students in environmental engineering -- Shuangyi Zhang and Stephen Gitungo -- are seeking to answer with their pioneering research.

These drugs and consumer products have resulted in thousands of new contaminants entering wastewater treatment plants, surface water and drinking water treatment systems.  And since they are new, the contaminants are unregulated.

As part of their research, Shuangyi and Stephen developed a list of “indicator” compounds that represent the vast array of unregulated contaminants. The two are evaluating the compounds and also assessing water treatment methods to see how effective they are in removing the compounds from the water supply.

“This research will contribute to optimizing conventional and advanced treatment processes by improving removal efficiencies," says Lisa Axe, a professor of civil and environmental engineering who advises the two.

 Their research is collaboration between NJIT and United Water, a subsidiary of Suez Environment. At United Water, the project is overseen by John Dyksen, Vice President of Capital Planning & Research and Robert Raczko, Senior Process Engineer.

Disposing of Metals from Old Paint

In another collaborative research project, this one between NJIT and Rowan University, Zhan Shu, a Ph.D. student in Environmental Engineering, is developing a model that the New York Department of Transportation will use to evaluate and dispose of paint waste that is generated during bridge rehabilitation.

Contractors use a common blasting technique to remove old paint from bridges.  But since surface or paint layers are often old, the technique can result in paint waste with elevated levels of lead and other metals such as arsenic and chromium.  And the problem is that these metals could leach in the landfills or wherever they are brought for disposal.

Zhan took paint samples collected during bridge rehabilitation projects from 24 bridges in 11 regions of New York.  She evaluated the samples at the bridge sites, using portable testing equipment, and in the Metals Lab at NJIT, which allows for more rigorous analysis.  She is comparing the two sets of samples and developing a model that will predict metal leaching from paints. The research project is funded by the New York State Department of Transportation through the University Transportation Research Center.

The model will also help the DOT characterize the metals and determine the safest way to dispose of them.

“This research will help NYSDOT with the proper disposal of hazardous waste,” says Lisa Axe, her adviser. “Zhan is also helping to safeguard our environment. For a graduate student to do something that environmentally important is really impressive.”

By Robert Florida