Recent studies demonstrated that advanced aerogel composites (Aspen Aerogels®Spaceloft®[SL]) have the potential to transform oil remediation via high oil uptake capacity and selectivity, excellent reusability, and high mechanical strength. Understanding the life cycle environmental impacts of advanced aerogels can enable a more holistic decision‐making process when considering oil recovery technologies following a spill. Here, we perform a cradle‐to‐grave streamlined life cycle assessment (LCA) following International Organization for Standardization (ISO) 14040 2006 for SL weighed against the conventional oil sorbent material, polyurethane foam. The model included alternative use and disposal scenarios, such as single or multiple uses, and landfill, incinerator, and waste‐to‐energy (WTE) approaches for cleaning 1 cubic meter (m3) of light crude oil. Results showed that the ideal case for SL application was comprised of multiple use and WTE incineration (68% reduction in material use, approximately 7 × 103megajoules [MJ] of energy recovery from WTE), but SL offered energy and materials savings even when used once and disposed of via traditional means (i.e., landfill). In addition to evaluating these already‐scaled processes, we performed an anticipatory LCA for the laboratory‐scaled aerogel fabrication process that might inform the sustainable design of next‐generation aerogels. In particular, the model compared rapid supercritical extraction (RSCE) with two conventional supercritical extraction methods—alcohol and carbon dioxide supercritical extraction (ASCE and CSCE, respectively)—for silica aerogel monoliths. Our results showed that RSCE yielded a cumulative energy savings of more than 76 × 103and 100 × 103MJ for 1 m3of monolithic silica aerogel manufacturing compared to ASCE and CSCE, respectively.
Additive manufacturing (AM) of aerogels increases the achievable geometric complexity, and affords fabrication of hierarchically porous structures. In this work, a custom heated material extrusion (MEX) device prints aerogels of poly(phenylene sulfide) (PPS), an engineering thermoplastic, via in situ thermally induced phase separation (TIPS). First, pre‐prepared solid gel inks are dissolved at high temperatures in the heated extruder barrel to form a homogeneous polymer solution. Solutions are then extruded onto a room‐temperature substrate, where printed roads maintain their bead shape and rapidly solidify via TIPS, thus enabling layer‐wise MEX AM. Printed gels are converted to aerogels via postprocessing solvent exchange and freeze‐drying. This work explores the effect of ink composition on printed aerogel morphology and thermomechanical properties. Scanning electron microscopy micrographs reveal complex hierarchical microstructures that are compositionally dependent. Printed aerogels demonstrate tailorable porosities (50.0–74.8%) and densities (0.345–0.684 g cm−3), which align well with cast aerogel analogs. Differential scanning calorimetry thermograms indicate printed aerogels are highly crystalline (≈43%), suggesting that printing does not inhibit the solidification process occurring during TIPS (polymer crystallization). Uniaxial compression testing reveals that compositionally dependent microstructure governs aerogel mechanical behavior, with compressive moduli ranging from 33.0 to 106.5 MPa.
more » « less- NSF-PAR ID:
- 10478160
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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