March
24, 2006 --- The New High Efficiency Nano-Catalyst
Immobilization ( HENCI ) technology
by Cross Technologies is unleashing, for the first
time ever, the immense potential of nanocatalysis for
large-scale Groundwater Remediation (GWR): to treat
recalcitrant carcinogen-contaminated groundwater
(often to potable quality) on-demand, at any throughput,
in a small, inexpensive, well-head / point-of-distribution
/ mobile unit, by eliminating carcinogenics altogether (chemically
breaking them down into benign species, not simply
trapping them in a medium, concentrating them in
an effluent or evaporating them to our air). With
process-cost efficiencies literally orders of magnitude
greater than conventionally available technologies,
HENCI facilitates the use of nano-catalysts (NCs)
in a completely new way, opening the flood-gates
for the application of nanotechnology to environmental
and industrial nano-catalytic and -sorbtive processes.
The new genres of nano-sized catalysts are very exciting. When polluted water
is exposed to them, rapid and complete catalytic destruction, i.e. chemical
breakdown to benign species, of at least 40 recalcitrant carcinogenic groundwater
pollutants has been shown to take place. Pollutants include chlorinated alkanes,
alkenes and aromatics, THMs, DDT, Lidane, PCBs, Dioxins, TNT, NDMA, Organic
Dyes, dichromates, perchlorate, pharmaceutical residuals, and others of immediate
concern, many on the EPA-'Hotlist' (section 307, CWA). Hence, the desire to
use highly effective NCs for various large-scale ground water remediation (GWR)
applications is well established. However, the attribute most important to
their high-efficacy - their nano-scale size - is also their Achilles' heel,
and has greatly inhibited their commercialization via both in-situ and ex-situ operation.
Why? Firstly, no method for in-situ use of NCs has proven truly viable,
including sub-surface injection, reactive barriers, or in-situ surface treatment
(NCs added to surface-storage tanks to break down pollutants before water is
used). This is because most NCs are themselves toxic, so any in-situ use
necessitates that, after exposure, all the NCs, in turn, be completely removed
from the treated water prior to use . Because these particles are so small
(and numerous), high-performance R.O./Nano-filtration is usually required to
accomplish such removal, rendering the overall operation much too expensive.
Thus, on-demand ex-situ use of NCs has been proposed as a superior
alternative because it eliminates the need for post-reaction removal of the
NCs by 'immobilizing' them (usually on or within a support media) - preventing
them from entering into solution in the treated water in the first place. As
such, ex-situ operation is theoretically conducive to more-efficient
'continuous' processing, e.g. in a flow-through reactor. Until HENCI, however,
no immobilization technology was even close to being viable for field application,
as all fell short of meeting the seven formidable engineering challenges
/ criteria necessary for cost-effective immobilization NCs for any practical
applications :
- Complete Immobilization - no
undesired release of nano-particles.
- Ultra-high Particle Loading Densities within
the reactor to fully exploit their high SA/mass
ratios, or over about 25x10 15 particles per cubic
inch of reactor volume.
- High Mass-transport Efficiency
- Micro-homogeneity - particles are immobilized
in an evenly spaced, three-dimensional mono-dispersion
through which the untreated water flows,
exploiting NC's extremely high reactive surface
area.
- No Particle Surface Coverage -100% of each
catalyst particles' surface area is directly
exposed to reactant
- High Momentum-transport Efficiency -
high linear velocities with ultra-small pressure
drops.
- Complete Scalability to
commercial-volume treatment w/ >99.999% conversion
efficiency of even ppb-level pollutants.
- Low
Cap. & Op. costs : no
expensive media or polluted effluent disposal issues;
ambient operation, no moving parts
- Potential for quick regulatory-agency
acceptance - safe, easily-controlled
operation, no add'l contact materials
HENCI-facilitated nanocatalysis meets all these
criteria, and is thus uniquely poised to usher in
a new era in GWR marked by our ability to easily
process polluted groundwaters to potable quality
with a true leap in environmental benevolence, let
alone the benefits to be reaped in commercial applications.
Contact:
Ken Cross
760-944-9778
crosstechnologies@adelphia.net
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