(139a) Ultralight, Reusable Cellulose Diacetate Aerogels for Selective Fluid Sorption

Tripathi, A., North Carolina State University
Khan, S. A., North Carolina State University
Rojas, O. J., North Carolina State University

oil or chemical spillage into fresh water can trigger a cascade of events
including toxic loading and contamination of food resources, all of which are
heavily detrimental to the ecosystem1,2. Widespread
technologies proposed to deal with oil spills include oil skimming, in-situ
burning, mechanical containment and utilization of dispersants, solidifiers and
degrading microorganisms3–8. However, these
methods are either inefficient or environmentally unfriendly. The need for
efficient oil spill cleaning technologies was imminent in 2010 deep water
horizon spill, one of the largest man-made disasters in the recent history,
where oil gushed out in the Gulf of Mexico for straight 87 days, pouring out
over 200 million gallons of crude oil9. In this type of
scenario, the use of sorbents is attractive as they are easy to deploy and do
not generate byproducts. There are three categories of sorbent materials:
organic (milkweed, wood chips, rice straw, among others), inorganic
(organo-clay, perlite and sand, zeolites, etc.) and synthetic (non-woven
polypropylene mats, for example).10–12 However, they (1)
suffer from low sorption capability (typically less than 10 g per gram of solid
support); (2) are difficult to recover (they are not buoyant), and (3) are not

In recent years, aerogels
have gained attention as sorbent materials because of their light weight and
high pore volume. In this study, highly porous (99.7% air volume) and
ultra-light (4.3 mg/ml density) cellulose ester aerogels were synthesized for
unprecedented water uptake (45-90 g/g) while affording wet strength and
mechanical robustness (maximum compressive stress and strain of 350 kPa and
92%, respectively). The high compression strains are generally achieved with carbon
nanofiber aerogels but the 92% strain is higher than those of nanocellulose
aerogel reported in literature. The compressive stress of 350 kPa is 100 times
higher than the reported cellulosic aerogels (see Figure 1). The aerogels were
further adjusted towards hydrophobicity and oleophilicity via chemical vapor
deposition with an organo-silane species. The as-modified aerogel exhibited
high oil retention (20-30 g/g aerogel) while maintaining mechanical integrity
for fast oil cleanup from aqueous media under marine conditions.

Figure 1:
a) Image of a 2 w/v% aerogel (density 4.3 mg/ml) on a dandelion leaf; b)
Compressive stress-strain profile for 4 w/v% aerogels with the maximum
compressive stress of 350 kPa and maximum strain of 92%. Inset: SEM image
showing the radial cross-section of 4 w/v% CDA aerogel with a “honeycomb” like


1.        Aguilera
F, Méndez J, Pásaroa E, Laffona B. Review on the effects of exposure to spilled
oils on human health. J Appl Toxicol. 2010;30(4):291-301.

       Burton NHK, Musgrove  a. J, Rehfisch MM, Clark N a. Birds of the Severn
Estuary and Bristol Channel: Their current status and key environmental issues.
Mar Pollut Bull. 2010;61(1-3):115-123.

       Fingas M. Oil Spill Science and Technology. Elsevier, Amsterdam.

       Fingas M. “In-situ burning” in Oil Spill Science and Technology. In: Elsevier.
Gulf publishing company, New York NY; 2011:737-903.

       Michel J, Adams EE, Addassi Y, et al. Oil Spill Dispersants. Efficacy
and Effects
. Washington, DC; 2005.

       Rosales PI, Suidan MT, Venosa AD. A laboratory screening study on the
use of solidifiers as a response tool to remove crude oil slicks on seawater. Chemosphere.
2010;80(4):389-395. doi:10.1016/j.chemosphere.2010.04.036.

       Correa M, Padron E, Petkoff I. The San Rafael De Laya oil spill :
A Case of cleanup and remediation in Venezuela. In: International Oil Spill
.; 1997:932-935.

       Aldhous P, Hecht J. Beware long-term damage when cleaning up oil spills.
New Sci. 2010;10(206):2765. doi:10.1016/S0262-4079(10)61464-9.

       Graham B, Reilly WK, Beinecke F, Boesch DF, Garcia TD, Murray C a. Deep
Water: The Gulf Oil Disaster and the Future of Offshore Drilling
.; 2011.

     Teas C, Kalligeros S, Zanikos F, Stournas S, Lois E, Anastopoulos G.
Investigation of the effectiveness of absorbent materials in oil spills clean
up. Desalination. 2001;140(3):259-264.

     Adebajo MO, Frost RL, Kloprogge JT, Carmody O, Kokot S. Porous Materials
for Oil Spill Cleanup : A Review of Synthesis. J Porous Mater.
2003;(10):159-170. doi:10.1023/A:1027484117065.

     Carmody O, Frost R, Xi Y, Kokot S. Adsorption of hydrocarbons on
organo-clays-Implications for oil spill remediation. J Colloid Interface Sci.
2007;305(1):17-24. doi:10.1016/j.jcis.2006.09.032.