Chemical Engineering January 2017 - 7

Chementator
A process for making longer carbon nanotubes
Nanocomp Technologies
new commercial manufacturing
process for carbon nanotubes
(CNTs) produces tubes
in the range of 1-10 mm in
A
length (5-12-nm dia.), two orders
of magnitude longer than currently
available CNTs, which typically have
lengths from 5-20 µm.
" Despite attractive mechanical and
electrical properties, CNTs have largely
been a disappointment for 'real-world'
applications, because it has not been
possible to make them in formats that
are useful for engineers, " explains
Peter Antoinette, co-founder and president
of Nanocomp Technologies Inc. (Merrimack,
N.H.; www.nanocomptech.com), the
developer of the process. Short CNTs do not
readily form networks within other materials,
unless used at very high concentrations.
The Nanocomp process revolves around a
proprietary 1-m long heated reactor (photo)
that contains a widely available iron catalyst
and allows control of 23 separate process
variables. Organic alcohols serve as the
carbon source for CNTs. " By exerting tight
control over the process conditions, we can
manipulate the length and dimensions of the
CNTs, " Antoinette says. The longer, polymer-like
CNTs resulting from the process
are commercially available as Miralon products,
and they can be spun into " yarn " using
equipment for textile fiber processing. Because
of their length, the Nanocomp CNTs
form bundles and networks that allow them
to be more useful in macroscale materials,
such as for lightweight structural materials.
" Our process allows CNTs to be made at
high volumes with a cost structure that is
similar to that of commodity chemicals, " Antoinette
says.
Nanocomp CNTs can also be made into
strong polymer-like sheets that can be used
in firearm-protection armor. The U.S. Dept.
of Defense recently awarded the company
$18.5 million to supply soldier and law enforcement
body armor. The sheets can also
be used as area heaters, Antoinette says,
because they emit infrared radiation when
low-energy power is applied.
Nanocomp currently produces its CNTs at a
scale of 2 tons/yr and plans to triple its manufacturing
capacity in 2017. Eventually, capacity
could reach 20 tons/yr, Antoinette says, adding
that the rapid growth has been helped greatly
by support for nanotechnology manufacturing
from the state of New Hampshire.
This process converts organic food waste to
liquid fertilizer
L
arge supermarkets routinely waste
500 lb of food daily from past-due
produce, deli and meat scraps and
other sources. A new process developed
by California Safe Soil (CSS; McClellan,
Calif.; www.calsafesoil.com) converts
the nutrient-rich waste food into a liquid fertilizer
for farmers.
After a series of grinding steps, the waste
food enters a ribbon-blender digester, where
enzymes are added to break down proteins,
carbohydrates and fats in the organic waste
into amino acids, simple sugars and fatty
acids. The mixture then undergoes mechanical
emulsification and pasteurization processes.
The liquid product, containing oiland
water-based nutrients, is stabilized with
phosphoric acid, and can be used to fertilize
root systems of farm crops. The solid portion
of the organic waste is used in pig feed.
" The liquid fertilizer, known as Harvest-toHarvest
(H2H), adds organic matter to the
root zone of crops and stimulates the growth
of beneficial soil microbes, which generates
additional root growth. Plants take up more
water and fertilizer, and increase flowering
and fruiting, " explains CSS founder Dan
Morash. " It also reduces the need for nitrate
fertilizers on farms, which reduces farm runoff
and algae blooms in nearby bodies of
water, " Morash says.
Food waste is collected from supermarkets
in insulated totes and buggies and is
processed locally, because the CSS process
generates no waste streams or nuisance
odors, Morash points out. Liquid fertilizer
has advantages over solid compost,
because it can be dripped into the root systems
using existing irrigation systems, rather
than staying on the soil surface, he adds.
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM
JANUARY 2017
Edited by:
Gerald Ondrey
HVAC COOLING TOWER
A newly introduced cooling
tower for building heating,
ventilation and air conditioning
(HVAC) has both
its structural casing and fill
made
from
high-density
polyethylene (HDPE) resin
that contains additives designed
to prevent the growth
of microorganisms and formation
of biofilms within the
cooling tower. The anti-microbial
HDPE cooling tower
was recently introduced by
Delta Cooling Towers Inc.
(Roxbury
Township,
N.J.;
www.deltacooling.com)
to address concerns over
pathogenic microbes, such
as the bacteria species that
causes Legionnaire's disease.
Under certain conditions,
the bacteria can be
incubated and spread by
water systems. The cooling
tower's design also avoids
stagnant water areas, where
microorganisms can grow,
the company says.
PHOTOSYNTHESIS
Fujitsu Laboratories Ltd.
(FLL; Kawasaki City, www.
fujitsu.com) has developed a
new process for layering thin
films of inorganic photocatalysts
onto a substrate. Using
a proprietary nozzle, the catalyst
precursors are sprayed
onto a thin plate, and are
fragmented into nano-sized
particles that deposit on the
substrate. Because of the
enhanced (50-fold) increase
in surface area compared
to alternative methods, and
the ability of the catalyst
to operate over a broader
spectrum of usable sunlight
(lmax = 630 nm, compared
to lmax = 490 nm for existing
catalysts), the new catalyst
shows a 100-fold efficiency
for the oxygen-producing
step of photosynthesis.
FLL plans to further develop
the technology, with industrial
applications projected
for 2025.
(Continues on p. 8)
7
http://www.nanocomptech.com http://www.deltacooling.com http://www.fujitsu.com http://www.calsafesoil.com http://WWW.CHEMENGONLINE.COM
Chemical Engineering January 2017

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