Chemical Engineering April 2020 - 7

Chementator
Conversion of plastic packaging to
BTX and olefins is demonstrated
nellotech (Pearl River, N.Y.;
www.anellotech.com) recently
announced a successful laboratory
demonstration of a process
to convert mixed plastic waste into a
host of useful starting materials for new
plastics. The process (diagram), known
as Plas-T-Cat, would take place in a
fluidized-bed reactor, and is envisioned
to convert plastics, such as thin-film
snack-bag packaging, into olefins (ethylene
and propylene), BTX (benzene, toluene
and xylenes) and other products.
With heat to effect polymer chain
cracking, and ZSM-5 zeolite
A
Plas-T-Cat
reactor
Plastics
feed
Recycle gas
catalysts to
control the reforming reactions from the pyrolysis
gas, Anellotech's proprietary process
has the potential to, within the same unit,
convert polyolefins alone or as part of composite
packaging. " The catalytic pyrolysis
has the potential to generate commercially
relevant yields of olefins, while reducing the
mixture of waxes that you would see in a
non-catalytic process, " explains David Sudolsky,
CEO of Anellotech. " Alternatively, we
can adjust the operating conditions to obtain
a higher proportion of BTX, along with
lower-molecular-weight olefins, paraffins, C5
A
n international team, led by Mahdokht
Shaibani from Monash University
(Melbourne, Australia; www.
monash.edu), has developed an
ultra-high capacity lithium-sulfur battery with
better performance and lower environmental
impact than current Li-ion batteries.
The team includes people from Monash
University, University of Liège (Belgium),
Fraunhofer Institute for Material and Beam
Technology (Dresden, Germany), Technische
Universität Dresden (Germany), and CSIRO
(Melbourne, Australia; www.csiro.au).
Using sulfur cathodes in Li-S batteries and
silicon anodes in Li-ion batteries is the most
attractive example of inexpensive electrodes
with excellent ability to store lithium, and
hence the potential to outperform today's Liion
batteries. However, a problem with these
electrodes is the structural fragmentation associated
with the volume change during the
absorption and release of large quantities of
lithium. These changes lead to a loss of cohesion
of particles and permanent distortion of
the polymer binder and carbon matrix, both
of which contribute to loss of capacity.
According to the team, little attention has
been devoted to the mechanical failure of thick
Steam
Reactor
effluent gas
product
Regenerator
fluegas
Edited by:
Anellotech Gerald Ondrey
Regenerator
Regenerated
catalyst
Stripper*
Coked
catalyst
+ char
Steam
Air
Regeneration air
blower
liquids and other compounds. "
It is believed that the Anellotech process
can deal with the unique set of contaminants
observed in multi-layer packaging, such as
color and an aluminum layer, says Sudolsky.
The plastic-waste process is related to the
company's Bio-T-Cat process, which converts
biomass to BTX, and has been operating
at pilot scale since 2018 (Chem. Eng.,
March 2016, p. 7).
Anellotech is nearing completion of engineering
work for the first commercial-scale
Bio-T-Cat plant, and will leverage the existing
development infrastructure to pilot the new
Plas-T-Cat process.
Progress towards lithium-sulfur batteries
cathodes in cycling duty. Binders, essential in
the electrode composition to glue the active
material and conductive agent together and
also to the current collector, must be able to
make crack-free cathodes. Thick cathodes, if
started at high capacities, showed rapid degradation
due to the mechanical failure or did
not deliver high capacities.
The team reported that controlling the
dispersion of Na-carboxymethylcellulose (a
commonly used binder) enables the formation
of mechanically strong bridging bonds
between the fillers - in the case of the
team's work, colloidal sulfur and conductive
carbon. The team fabricated four types of
thick sulfur cathodes with identical compositions
(70% colloidal S, 20% C, and 10%
carboxymethylcellulose) yet using different
slurry preparation methods. Scanning electron
microscopy was used to investigate
the effect of slurry preparation on the morphology
of these cathodes. The method the
team used efficiently converted the compact
microstructure into a unique architecture
with an increase in free space to potentially
accommodate the cycling stresses, and deliver
a higher level of stability than that seen
in any battery to date.
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM
APRIL 2020
Catalyst cooler
Li2CO3 FROM BRINE
Purities of greater than
99.9% for battery-quality
lithium
been
carbonate
achieved
have
using
a proprietary artificialintelligence-powered
crystallization
technology
developed
by
Standard
Lithium Ltd. (Vancouver,
B.C.; www.standardlithium.com).
The total cation
contaminant levels were
reduced from nearly 2,500
parts per million (ppm) to
less than 139 ppm in the
crystallization. Optimization
work for the crystallization
process,
known
as SiFT, was conducted
at the University of British
Columbia, and supports
separate work related to
the ongoing commissioning
of Standard Lithium's
LiSTR Direct Lithium Extraction
demonstration
plant in the Smackover
brine region in south Arkansas
(Chem. Eng., July
2018, p. 9). The first-ofits-kind
demonstration
plant will use the Standard
Lithium's proprietary technology
to selectively extract
lithium from tailbrine
that comes from a nearby
Lanxess facility.
'GREENER' ASPHALT
Last month, representatives
from 22 organizations
met at the Tech Park
in Delft, the Netherlands
for the official start of the
bio-based-asphalt cooperation
program,
called
CHAPLIN
(Collaboration
in aspHalt APplications
with LIgniN). The cooperation
aims to stimulate
the development and
commercialization of lignin-containing
asphalt, as
an alternative to bitumen
from petroleum.
" There is a lot of interest
worldwide for lignin as a
sustainable raw material
for bio-asphalt, " says lig(Continues
on p. 8)
7
http://www.anellotech.com http://www.standardlith http://www.ium.com http://www.monash.edu http://www.csiro.au http://WWW.CHEMENGONLINE.COM
Chemical Engineering April 2020

Table of Contents for the Digital Edition of Chemical Engineering April 2020
