'Frozen Smoke:' Ultimate Sponge For Cleaning Up Oil Spills

ScienceDaily (Feb. 17, 2009) — Scientists in Arizona and New Jersey are reporting that aerogels, a super-lightweight solid sometimes called “frozen smoke,” may serve as the ultimate sponge for capturing oil from wastewater and effectively soaking up environmental oil spills.

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Aerogels, a super-lightweight solid sometimes called "frozen smoke," may capture oil from wastewater and soak up environmental oil spills. (Credit: NASA/JPL)

In the new study, Robert Pfeffer and colleagues point out that the environmental challenges of oil contamination go beyond widely publicized maritime oil spills like the Exxon Valdez incident.

Experts estimate that each year people dump more than 200 million gallons of used oil into sewers, streams, and backyards, resulting in polluted wastewater that is difficult to treat. Although there are many different sorbent materials for removing used oil, such as activated carbon, they are often costly and inefficient. Hydrophobic silica aerogels are highly porous and absorbent material, and seemed like an excellent oil sponge.

The scientists packed a batch of tiny aerogel beads into a vertical column and exposed them to flowing water containing soybean oil to simulate the filtration process at a wastewater treatment plant. They showed that the aerogel beads absorbed up to 7 times their weight and removed oil from the wastewater at high efficiency, better than many conventional sorbent materials.

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Journal reference:

1. Quevedo et al. Removal of Oil from Water by Inverse Fluidization of Aerogels. Industrial & Engineering Chemistry Research, 2009; 48 (1): 191 DOI: 10.1021/ie800022e

Adapted from materials provided by American Chemical Society.

UPS is First in Delivery Industry to Test Hydraulic Hybrid Vehicles: 50% Better Fuel Economy and 40% Lower Emissions

Written by Nick Chambers

Published on October 28th, 2008

In partnership with the US Environmental Protection Agency, UPS will begin testing a small fleet of hydraulic hybrid delivery trucks in the United States. The new vehicles can achieve 50-70% better fuel economy, a 40% reduction in greenhouse gas emissions, and pay for their extra expense in less than 3 years.

UPS will field two hydraulic hybrids in Minneapolis, MN, in early 2009 and an additional five hydraulic hybrid trucks will be deployed later in 2009 and early 2010. Although this sounds like a tiny fleet, keep in mind that this is the largest scale commercial test of hydraulic hybrids ever conducted.

The UPS hybrid hydraulic truck is a standard-looking 24,000 pound package car, with an EPA-patented diesel series hydraulic hybrid drive attached to the rear axle.

In a series hydraulic hybrid, the conventional drivetrain is replaced with a hydraulic system that stores energy by compressing gas in a chamber using hydraulic fluid. It works in much the same way that a hybrid electric car does — a small, efficient motor generates power which gets stored for later use — only, the way energy is stored in a hydraulic hybrid is in a pressurized chamber rather than in a battery.

The hydraulic hybrid drivetrain eliminates the need for a conventional transmission and increases fuel economy in three ways:

1. A large amount of the energy that is otherwise wasted in braking can be recovered to pressurize the hydraulic fluid.
2. The engine operates much more efficiently — similar to a hybrid electric car, only without the bulky batteries
3. The engine can easily be shut off and instantaneously restarted during regular driving — such as when the vehicle is slowing down or stopped at a light.

UPS has been developing what it calls its “green fleet” over the last several years and currently has more than 1,600 low carbon emissions vehicles including electric, hybrid-electric, compressed natural gas, liquefied natural gas, and propane trucks.

Although this is a small step, I applaud UPS for testing the waters. Hopefully others will join in quickly.

Source: UPS press release
Image Credit: UPS