Featured Research

from universities, journals, and other organizations

Better catalysts for petrochemical industry

Date:
May 28, 2014
Source:
ETH Zurich
Summary:
When crude oil is refined to fuels and chemicals, help is at hand -- in the form of so-called catalysts. Scientists now provide a reference parameter for the performance of an important class of catalysts for petrochemical production.

Zeolites are among the substances which can accelerate chemical reactions -- they are known as catalysts. Usually applied in pellet form, the industrial production of gasoline from crude oil without zeolites is today inconceivable. The chemical reactions occur on their surface. Fortunately, these are very large for zeolites: the catalysts are interspersed with nano-sized pores and microscopic channels through which gaseous or liquid reactants penetrate and the products later can leave.

One of the main industrial problems with the use of zeolites is that the reaction side products clog the pores or block the active sites of the catalyst. Experts call such hydrocarbon deposits 'coke'. Consequently, the production needs to be interrupted at regular intervals to burn off the debris formed in the catalyst, thereby regenerating the latter. This reduces the efficiency of the process.

It all depends on the inner structure

Researchers are therefore working to make zeolite catalysts more resistant to such deposits, thereby delaying the need for regeneration and thus, extending the production cycles. Researchers from ETH Zurich headed by Javier Pérez-Ramírez, a professor of catalysis engineering, have now identified the relation between this resistance and the internal structure of a new class of zeolite catalysts combining a complex network of pores of various sizes: "It is not only about the providing the greatest number of pores, as was previously thought," says Sharon Mitchell, researcher in the group of Pérez-Ramírez. "Rather it is crucial that the nano-sized channels are well connected within the zeolite catalysts and has numerous openings to the outside." This facilitates the penetration of the chemical compounds into the catalyst even when some of the pores are blocked.

The researchers came to this realization by preparing catalysts with diverse pore structures in the laboratory. To achieve this they used different synthesis methods and conditions. The catalysts were subsequently studied in collaboration with Paolo Crivelli, researcher at the Department of Physics, with positron annihilation lifetime spectroscopy (PALS). This technique measures how long the positrons reside within the catalyst. The more connected the pores are, and the greater the number of openings, the faster the positrons can escape from the zeolite. In addition, the scientists assessed how quickly coke deposits formed within the various zeolite catalysts in their laboratory.

Not only better, but also cheaper

"Interestingly, the method by which we could make the most resistant zeolites, was also the cheapest," says Pérez-Ramírez. He expects that the results of the study, published in the journal Nature Communications, will animate industry to adopt their zeolite manufacturing process.

Zeolite catalysts are currently used on a large scale in the petroleum industry to produce high-grade propellants, fuels and raw materials for the chemical industry. On the one hand, large hydrocarbon molecules in the crude oil can be broken down into more useful medium-sized molecules. On the other hand, zeolites can also be used to couple very small hydrocarbons -- such as ethene and propene -- to obtain higher quality products also of medium chain length. "Even as oil is gradually one day replaced by renewable feedstocks, such as biomass, zeolite catalysts will retain their importance," says Pérez-Ramírez. Premium base chemicals could be produced in an efficient manner using zeolite catalysts.


Story Source:

The above story is based on materials provided by ETH Zurich. Note: Materials may be edited for content and length.


Journal Reference:

  1. Maria Milina, Sharon Mitchell, Paolo Crivelli, David Cooke, Javier Pérez-Ramírez. Mesopore quality determines the lifetime of hierarchically structured zeolite catalysts. Nature Communications, 2014; DOI: 10.1038/ncomms4922

Cite This Page:

ETH Zurich. "Better catalysts for petrochemical industry." ScienceDaily. ScienceDaily, 28 May 2014. <www.sciencedaily.com/releases/2014/05/140528105300.htm>.
ETH Zurich. (2014, May 28). Better catalysts for petrochemical industry. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2014/05/140528105300.htm
ETH Zurich. "Better catalysts for petrochemical industry." ScienceDaily. www.sciencedaily.com/releases/2014/05/140528105300.htm (accessed July 28, 2014).

Share This




More Matter & Energy News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Newsy (July 28, 2014) — Stanford University published its findings for a "pure" lithium ion battery that could have our everyday devices and electric cars running longer. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) — AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) — Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) — Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins