Navigation Links
One sponge-like material, three different applications
Date:5/17/2009

A new sponge-like material that is black, brittle and freeze-dried (just like the ice cream astronauts eat) can pull off some pretty impressive feats. Designed by Northwestern University chemists, it can remove mercury from polluted water, easily separate hydrogen from other gases and, perhaps most impressive of all, is a more effective catalyst than the one currently used to pull sulfur out of crude oil.

Hydrodesulfurization might be a mouthful, but it is also a widely used catalytic chemical process that removes sulfur from natural gas and refined petroleum products, such as gasoline and diesel and jet fuels. Without the process, which is highly optimized, we'd be burning sulfur, which contributes to acid rain.

Scientists have tried to improve hydrodesulfurization, or HDS, but have made no progress. Many consider it an optimized process. The Northwestern researchers, in collaboration with colleagues at Western Washington University, report that their material is twice as active as the conventional catalyst used in HDS while at the same time being made of the same parts.

The material, cobalt-molybdenum-sulfur, is a new class of chalcogels, a family of material discovered only a few years ago at Northwestern. (Chalcogels are random networks of metal-sulfur atoms with very high surface areas.) The new chalcogel is made from common elements, is stable when exposed to air or water and can be used as a powder.

Details of the cobalt-molybdenum-sulfur chalcogel and its properties will be published online May 17 by the journal Nature Chemistry. This is the first report of chalcogels being used for catalysis and gas separation.

"I was surprised at the impressive activity of our catalyst, given how difficult it has been to improve HDS," said Mercouri G. Kanatzidis, the paper's senior author. "In principle, our catalyst could process and desulphurize twice as much crude oil as the same amount of conventional catalyst. We currently are conducting studies to see how the catalyst operates under more commercial conditions."

Kanatzidis, Charles E. and Emma H. Morrison Professor of Chemistry in the Weinberg College of Arts and Sciences, and doctoral student Santanu Bag make their catalyst using a method different from that of the conventional catalyst.

The Northwestern material is a gel made of cobalt, nickel, molybdenum and sulfur that then is freeze-dried, producing a sponge-like material with a very high surface area. (One cubic centimeter has approximately 10,000 square feet of surface area, or about half a football field.) It is this high surface area and the material's stability under catalytic conditions that make the cobalt-molybdenum-sulfur chalcogel so active.

The researchers also demonstrated that the new chalcogel soaks up toxic heavy metals from polluted water like no other material. The chalcogel removed nearly 99 percent of the mercury from contaminated water containing several parts per million. Mercury likes to bind to sulfur, and the chalcogel is full of sulfur atoms.

Two years ago, Kanatzidis and Bag reported a chalcogel that could remove mercury from liquid, but the chalcogel contained expensive platinum; the new chalcogel contains only inexpensive elements, with cobalt and nickel replacing the platinum. The cobalt and nickel link through the sulfur atoms of the thiomolybdate anions to create a three-dimensional porous network.

"We succeeded in doing something very difficult: eliminating the platinum and only using common materials to create a gel," said Kanatzidis. "We found the proper conditions to get the properties we wanted. The key was changing the solvent from water to formamide."

In addition to being a better HDS catalyst and a mercury sponge, the chalcogel also is very effective at gas separation. The researchers showed that the material easily removes carbon dioxide from hydrogen, an application that could be useful in the hydrogen economy.

The gas separation process takes advantage of the 'soft' sulfur atoms of the chalcogel's surface. These atoms like to interact with other soft molecules passing by, slowing them down as they pass through. Hydrogen, the smallest element, is a 'hard' molecule. It zips right through while softer molecules like carbon dioxide take more time.


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology news :

1. Environmental exposures may damage DNA in as few as three days
2. Visualizing virus replication in three dimensions
3. Genome projects launched for three extreme-environment animals
4. Innerscope Research(R) Receives Three Great Minds Innovation Awards from the Advertising Research Foundation
5. Innerscope Research(R) Receives Three Great Minds Innovation Awards from the Advertising Research Foundation
6. Three prominent Cell Press journals named among the 100 most influential journals in past 100 years
7. Tiny details in three dimensions
8. Four, three, two, one . . . pterosaurs have lift off
9. Joslin research finds nearly three-quarters of youths with diabetes insufficient in vitamin D
10. Dwarf crocodiles split into three species
11. Wetlands expert: China should think outside the flooding box with Three Gorges Dam
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/15/2016)... DUBLIN , April 15, 2016 ... of the,  "Global Gait Biometrics Market 2016-2020,"  report ... http://photos.prnewswire.com/prnh/20160330/349511LOGO ) , ,The global gait ... CAGR of 13.98% during the period 2016-2020. ... movement angles, which can be used to compute ...
(Date:4/13/2016)... , April 13, 2016  IMPOWER physicians supporting Medicaid ... setting a new clinical standard in telehealth thanks to ... leveraging the higi platform, IMPOWER patients can routinely track ... and body mass index, and, when they opt in, ... convenient visit to a local retail location at no ...
(Date:3/31/2016)... -- Genomics firm Nabsys has completed a financial  restructuring under ... M.D., who returned to the company in October 2015. ... including Chief Technology Officer, John Oliver , Ph.D., ... Vice President of Software and Informatics, Michael Kaiser ... Bready served as CEO of Nabsys from 2005-2014 and ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... , June, 23, 2016  The Biodesign Challenge ... envision new ways to harness living systems and biotechnology, ... Art (MoMA) in New York City ... 130 participating students, showcased projects at MoMA,s Celeste Bartos ... Paola Antonelli , MoMA,s senior curator of architecture and ...
(Date:6/23/2016)... NC (PRWEB) , ... June 23, 2016 , ... In ... University Hospital in Denmark detail how a patient who developed lymphedema after being treated ... tissue. The results could change the paradigm for dealing with this debilitating, frequent side ...
(Date:6/23/2016)... , June 23, 2016 On ... session at 4,833.32, down 0.22%; the Dow Jones Industrial Average ... 500 closed at 2,085.45, down 0.17%. Stock-Callers.com has initiated coverage ... INFI ), Nektar Therapeutics (NASDAQ: NKTR ), Aralez ... Inc. (NASDAQ: BIND ). Learn more about these ...
(Date:6/23/2016)... , June 22, 2016  Amgen (NASDAQ: ... the QB3@953 life sciences incubator to accelerate ... The shared laboratory space at QB3@953 was created to ... key obstacle for many early stage organizations - access ... the sponsorship, Amgen launched two "Amgen Golden Ticket" awards, ...
Breaking Biology Technology: