New Materials Remove Corrosive Gas In Coal-Gasification Process

October 31, 1997

CHAMPAIGN, Ill. - Advanced coal-gasification processes are emerging as the most promising technology for converting coal into electricity, but the process generates sizable quantities of hydrogen sulfide, a highly corrosive gas that can destroy pipes and turbines. Chemical engineers at the University of Illinois and the Illinois State Geological Survey are developing materials to remove the hydrogen sulfide and convert it into economically valuable byproducts.

"A typical coal-fired power plant is about 33 percent efficient at generating electricity, while a coal gasifier is up to 50 percent efficient," said Mark Cal, a U. of I. professor of environmental engineering who also is a chemical engineer with the Survey. "Higher efficiency means that fuel can be conserved and greenhouse-gas emissions like carbon dioxide and acid-gas emissions like sulfur dioxide and the nitrogen oxides can be reduced. To achieve maximum performance in coal-gasification plants, an efficient and economical method of removing the hydrogen sulfide from the hot coal gas must be found."

Cal and his colleagues -- environmental engineering professor Mark Rood, Survey scientist Anthony Lizzio and graduate student Brooks Strickler -- are developing carbon-based sorbents that can remove the hydrogen sulfide efficiently.

"While the use of carbon for hot-gas cleanup has had significant potential, previous research has focused mainly on metal-based sorbents such as zinc ferrite, zinc titanate and various copper oxides," Cal said. "But each of these sorbents suffers from at least one major deficiency that prevents its widespread use."

Carbon offers several advantages over metal-based sorbents, Cal said. "Carbon provides excellent resistance to chemical and physical degradation in the harsh coal-gas environment. Carbon adsorbs large quantities of hydrogen sulfide, and can be used as an active support for metals -- such as copper and zinc -- which can enhance the adsorption process. And, carbon is inexpensive."

In their recent study, Cal and his colleagues developed a number of carbon-based sorbents and tested the ability of each sorbent to remove hydrogen-sulfide under different operating conditions. The regenerability of the most promising sorbents also was assessed.

"We've shown that these relatively inexpensive materials can very effectively remove hydrogen sulfide from the hot coal-gas stream," Cal said. "As an added bonus, the hydrogen sulfide that collects on the sorbent can be easily converted into commercially valuable products, such as solid sulfur and sulfuric acid."

Cal presented the team's findings at the September national meeting of the American Chemical Society in Las Vegas.
-end-


University of Illinois at Urbana-Champaign

Related Zinc Articles from Brightsurf:

Scientists evaluated the perspectives of zinc intake for COVID-19 prevention
Researchers from Sechenov University in collaboration with colleagues from Germany, Greece and Russia reviewed scientific articles on the role of zinc in the prevention and treatment of viral infections and pneumonia, with projections on those caused by SARS-CoV-2.

Putting zinc on bread wheat leaves
Applying zinc to the leaves of bread wheat can increase wheat grain zinc concentrations and improve its nutritional content.

A nanoscale laser made of gold and zinc oxide
Tiny particles composed of metals and semiconductors could serve as light sources in components of future optical computers, as they are able to precisely localize and extremely amplify incident laser light.

Zinc lozenges did not shorten the duration of colds
Administration of zinc acetate lozenges to common cold patients did not shorten colds in a randomized trial published in BMJ Open.

Dietary zinc protects against Streptococcus pneumoniae infection
Researchers have uncovered a crucial link between dietary zinc intake and protection against Streptococcus pneumoniae, the primary bacterial cause of pneumonia.

Zinc could help as non-antibiotic treatment for UTIs
New details about the role of zinc in our immune system could help the development of new non-antibiotic treatment strategies for bacterial diseases, such as urinary tract infections (UTIs).

Zinc deficiency may play a role in high blood pressure
Lower-than-normal zinc levels may contribute to high blood pressure (hypertension) by altering the way the kidneys handle sodium.

Genetic polymorphisms and zinc status
Zinc is an essential component for all living organisms, representing the second most abundant trace element, after iron.

Autism is associated with zinc deficiency in early development -- now a study links the two
Autism has been associated with zinc deficiency in infancy. While it is not yet known whether zinc deficiency in early development causes autism, scientists have now found a mechanistic link.

Can chocolate, tea, coffee and zinc help make you more healthy?
Ageing and a low life expectancy are caused, at least partly, by oxidative stress.

Read More: Zinc News and Zinc Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.