Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
Carbon nanotube synthesis and detection : limiting the environmental impact of novel technologies
Abstract
dc:description.abstractDriven by commercial promise, the carbon nanotube (CNT) industry is growing rapidly, yet little is known about the potential environmental impacts of these novel materials. In particular, there are no methods to detect CNTs in environmental matrices (e.g., sediment) and thus, there is no way to study their transport or gauge ecological exposure. Thermal methods were developed to quantify CNTs in coastal sediments down to 10 ug per sample, which is sufficient to for CNTs in laboratory air, but not sufficient to measure contemporary levels of CNTs in the environment (which were estimated to be present at pg g-1 sediment levels using a dynamic mass balance model). In addition to the CNTs themselves, potential impacts of CNT production were assessed by monitoring emissions from a representative synthesis. An ethene-fed chemical vapor deposition process generated several compounds of environmental concern, including the greenhouse gas, methane, the hazardous pollutants, benzene and 1,3-butadiene, and toxic polycyclic aromatic hydrocarbons. By identifying critical CNT precursors (alkynes), I delivered these compounds without thermal pre-treatment and achieved rapid CNT growth. This approach reduced carbonaceous emissions by more than an order of magnitude, and lowered initial feedstock requirements and energetic demands by at least 20%, without sacrificing CNT yield.
Degree
thesis:*- Grantor dc:publisher
- Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
- Year dc:date.issued
- 2009
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Plata, Desiree L.
Subjects
dc:subject × 2Rights
- Language dc:language.iso
- en_US
Identifiers
dc:identifier.*- OAI identifier oai:identifier
- oai:darchive.mblwhoilibrary.org:1912/2970