Corporate Banner
Satellite Banner
Environmental Analysis
Scientific Community
Become a Member | Sign in
Home>News>This Article

Rice Scientists ID New Catalyst for Cleanup of Nitrites

Published: Monday, December 02, 2013
Last Updated: Monday, December 02, 2013
Bookmark and Share
Gold-palladium nanocatalysts set new mark for breakdown of nitrites.

Chemical engineers at Rice University have found a new catalyst that can rapidly break down nitrites, a common and harmful contaminant in drinking water that often results from overuse of agricultural fertilizers.

Nitrites and their more abundant cousins, nitrates, are inorganic compounds that are often found in both groundwater and surface water. The compounds are a health hazard, and the Environmental Protection Agency places strict limits on the amount of nitrates and nitrites in drinking water. While it’s possible to remove nitrates and nitrites from water with filters and resins, the process can be prohibitively expensive.

“This is a big problem, particularly for agricultural communities, and there aren’t really any good options for dealing with it,” said Michael Wong, professor of chemical and biomolecular engineering at Rice and the lead researcher on the new study. “Our group has studied engineered gold and palladium nanocatalysts for several years. We’ve tested these against chlorinated solvents for almost a decade, and in looking for other potential uses for these we stumbled onto some studies about palladium catalysts being used to treat nitrates and nitrites; so we decided to do a comparison.”

Catalysts are the matchmakers of the molecular world: They cause other compounds to react with one another, often by bringing them into close proximity, but the catalysts are not consumed by the reaction.

In a new paper in the journal Nanoscale, Wong’s team showed that engineered nanoparticles of gold and palladium were several times more efficient at breaking down nitrites than any previously studied catalysts. The particles, which were invented at Wong’s Catalysis and Nanomaterials Laboratory, consist of a solid gold core that’s partially covered with palladium.

Over the past decade, Wong’s team has found these gold-palladium composites have faster reaction times for breaking down chlorinated pollutants than do any other known catalysts. He said the same proved true for nitrites, for reasons that are still unknown.

“There’s no chlorine in these compounds, so the chemistry is completely different,” Wong said. “It’s not yet clear how the gold and palladium work together to boost the reaction time in nitrites and why reaction efficiency spiked when the nanoparticles had about 80 percent palladium coverage. We have several hypotheses we are testing out now. ”

He said that gold-palladium nanocatalysts with the optimal formulation were about 15 times more efficient at breaking down nitrites than were pure palladium nanocatalysts, and about 7 1/2 times more efficient than catalysts made of palladium and aluminum oxide.

Wong said he can envision using the gold-palladium catalysts in a small filtration unit that could be attached to a water tap, but only if the team finds a similarly efficient catalyst for breaking down nitrates, which are even more abundant pollutants than nitrites.

“Nitrites form wherever you have nitrates, which are really the root of the problem,” Wong said. “We’re actively studying a number of candidates for degrading nitrates now, and we have some positive leads.”

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,800+ scientific posters on ePosters
  • More than 4,000+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Water-cleanup Catalysts Tackle Biomass Upgrading
Rice University researchers register 4th ‘volcano plot’ for palladium-gold catalysts.
Tuesday, July 01, 2014
Graphene Oxide Soaks Up Radioactive Waste
Rice, Moscow State universities collaborate on solution to toxic groundwater woes.
Tuesday, January 15, 2013
Scientific News
Safer, Faster Way To Remove Pollutants From Water
Using nanoparticles filled with enzymes proves more effective than current methods.
Low Impact Fracking Fluid on Top at IChemE Global Awards
A novel fracturing fluid designed to make fracking greener.
Marine Invasive Species May Benefit From Rising CO2 Levels
Ocean acidification may well be helping invasive species of algae, jellyfish, crabs and shellfish to move to new areas of the planet with damaging consequences, according to the findings of a new report.
Game for Climate Adaptation
MIT-led project shows a new method to help communities manage climate risks.
Tufts Chemist Discovers Way to Isolate Single-crystal Ice Surfaces
Promises insights into climate, environment and age-old riddles, such as why no two snowflakes are alike.
Potential Indirect Effects of Humans on Water Quality
Newly studied class of water contaminants occur naturally, but are more prevalent in populated areas.
Rapid Method for Water, Air and Soil Pathogen Screening
Researchers at BGU and the Massachusetts Institute of Technology (MIT) have developed a highly sensitive, cost-effective technology for rapid bacterial pathogen screening of air, soil, water, and agricultural produce in as little as 24 hours.
First Results Describing Sick Sea Star Immune Response
Though millions of sea stars along the West Coast have perished in the past several years from an apparent wasting disease, scientists still don’t know why.
Microbe Sleuth
Tanja Bosak examines how life and the Earth evolved in tandem during their early history together.
The Age of Humans Controlling Microbes
Engineered bacteria could soon be used to detect environmental toxins, treat diseases, and sustainably produce chemicals and fuels.
Scroll Up
Scroll Down

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos