Featured Research

from universities, journals, and other organizations

Smart Filter Removes Sulfur, Refines Crude Oil

Date:
June 4, 1998
Source:
University Of Southern California
Summary:
A new, inexpensive filter efficiently removes sulfur and other impurities from crude oil and serves as a miniature refinery to upgrade the crude, a University of Southern California researcher reports.

Nanotech Device Promises Wide Applications

A new, inexpensive filter efficiently removes sulfur and other impurities from crude oil and serves as a miniature refinery to upgrade the crude, a University of Southern California researcher reports.

"In preliminary tests, our filter removes as much as 60% of the sulfur in a single pass," says Teh Fu Yen, Ph.D., a professor of environmental and civil engineering at the USC School of Engineering. Dr. Yen is developing the device with funding from Klinair Environmental Technologies, of Dublin, Ireland.

To make the filter, a mixture of two metals is heated to nearly 1,000 degrees Fahrenheit and sprayed through a nozzle. Emerging as a fine crystalline powder, this "intermetallic" substance is bonded to an inert substrate, such as carbon fiber.

The coated substrate is then packed into a hollow glass cylinder -- creating a large interior surface. The greater the surface, the higher the efficiency of the filter.

Crystals occur in an infinite variety of shapes. Yen can control the shape of the crystals by using certain chemicals. To remove sulfur, he treats the intermetallic powder to produce a crystalline structure containing small pits that match the size and shape of sulfur molecules.

"The crystalline structure can sort out the bad without affecting the good," says Yen. "Analogous methods of nanotechology might also be used to remove nitrogen compounds, metals and other impurities. South America, China, Canada and certain republics of the former Soviet Union have large reserves of crude that are heavily contaminated with sulfur, metals and other impurities. Intermetallic filters could purify such oils both efficiently and economically."

By altering the crystalline structure, variants of the intermetallic filter might also be used to treat sewage and purify wastewater, Yen suggests.

Yen says his sulfur-removing filter works best when the crude is mixed in an emulsion of water. In nature, petroleum is often found in that very sort of emulsion; and sometimes drillers create such emulsions by pumping water or steam into petroleum deposits to force out the crude.

Because of the polarity of oil molecules in a water emulsion, the petroleum's sulfur molecules tend to hide within clusters of hydrocarbon molecules called micelles, Yen explains. When sodium and calcium surfactants are added, he says, the emulsion changes polarity and the sulfur molecules move to the surface of the micelles, where they are exposed to the intermetallic filter.

When Yen first tested the filter, it not only removed the sulfur but also absorbed the surfactants. The device soon stopped working. But Yen found that running an electrical current through the filter and the oil and water emulsion forces the surfactants to stay in solution, thus preserving the desired polarity and allowing the filter to continue removing sulfur.

Periodically, the electrical current may be reversed to dislodge the accumulated impurities, which are removed. The filter can then be used again and again.

By fine-tuning several parameters, such impurities as oxygen compounds, nitrogen compounds and organometallic compounds can also be extracted from crude.

In its natural, unprocessed state, crude oil is a mixture of hydrocarbon compounds, and the mixture is found in thousands of variations. After the crude's volatile compounds have been taken off, three main parts remain. The thickest, heaviest and most viscous compounds are classified as asphaltene. Next come the resins. Last are the lighter compounds, known as gas oils.

In addition to removing impurities, Yen's filter serves as a miniature refinery. When crude passes through it, some of the asphaltene can be "cracked" and upgraded into resin. "We can reduce the asphaltene content by about 20%," says Yen.

By changing the electrical current, the filter also can do the reverse and turn some of the resin into asphaltene. "This application could improve the specifications of roofing and paving asphalt by increasing the asphaltene content," says Yen.

With further research, he predicts, we can someday use intermetallic filters to do much of the processing that petroleum refineries now perform. "We will no longer need high temperatures and pressures, just an array of inexpensive intermetallic filters to process the oil," he says. "The process -- and its products -- will be far more environmentally friendly."

Sulfur in petroleum pollutes the air when oil products burn. Sulfur in gasoline poisons the catalyst in catalytic converters and causes them to stop working. Refineries can remove the sulfur by heating the petroleum to 700 degrees Fahrenheit at 70 times atmospheric pressure, but that process is too expensive to be widely used today.

Yen has been studying the basic science of petroleum components for decades. Assisting him in the intermetallic filter research are environmental engineering graduate students Steve Lu, Iris Yang and Harry Mei.


Story Source:

The above story is based on materials provided by University Of Southern California. Note: Materials may be edited for content and length.


Cite This Page:

University Of Southern California. "Smart Filter Removes Sulfur, Refines Crude Oil." ScienceDaily. ScienceDaily, 4 June 1998. <www.sciencedaily.com/releases/1998/06/980604071454.htm>.
University Of Southern California. (1998, June 4). Smart Filter Removes Sulfur, Refines Crude Oil. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/1998/06/980604071454.htm
University Of Southern California. "Smart Filter Removes Sulfur, Refines Crude Oil." ScienceDaily. www.sciencedaily.com/releases/1998/06/980604071454.htm (accessed October 23, 2014).

Share This



More Matter & Energy News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) — Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Jet Sales Lift Boeing Profit 18 Pct.

Jet Sales Lift Boeing Profit 18 Pct.

Reuters - Business Video Online (Oct. 22, 2014) — Strong jet demand has pushed Boeing to raise its profit forecast for the third time, but analysts were disappointed by its small cash flow. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) — As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
Powered by NewsLook.com
What Is Magic Leap, And Why Is It Worth $500M?

What Is Magic Leap, And Why Is It Worth $500M?

Newsy (Oct. 22, 2014) — Magic Leap isn't publicizing much more than a description of its product, but it’s been enough for Google and others to invest more than $500M. Video provided by Newsy
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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