1. Introduction
Groundwater contamination is an ever present danger with the introduction and detection of
new chemicals that have been demonstrated as toxic in shallow aquifers and wells through evolving
industrial processes. Among the organic contaminants, due to its widespread use in spray, varnish, and
dry cleaning industries, trichloroethylene (TCE) is a major groundwater pollutant
The solubility
of TCE in water, its volatility, and lack of standard disposal practices have made it the focus of
remediation and monitoring studies In dosage exceeding 250 ppm, TCE is neurotoxic
and is classified as “probably carcinogenic in humans” by the International Agency for Research on
Cancer
Approaches for removal, degradation and detection of TCE have commonly included activated
carbon as a host and adsorbent. Even though activated carbon and naturally sourced
materials such as pine needle biochar have orders of magnitude advantages in cost, the use of
two-dimensional carbon based materials (graphene nanosheets, graphene oxides and various carbon
nanotubes (CNTs) with different chiralities) offers specificity in adsorption and remediation with
relatively lower % loading in membranes and composites. CNTs have continued to drop in price and
are now acceptable as applied materials in scalable processes including water purification
A large number of approaches that incorporate CNTs in hybrid and hierarchical systems take advantage of the aspect ratio and specific adsorption through surface functionalization. We discuss some of
these approaches in the following sections and provide context in terms of the effect of hierarchy,
catalytic availability, mobility, and specific adsorption. Section 2 is an examination of current strategies,
while Sections 3 and 4 present experimental and modeling results based on the perspective offered by
Section