Chemical Engineering July 2023 - 5

Chementator
Commercial debut for a
batch reverse-osmosis system
E
arlier this year,
Salinity Solutions
Ltd. (Coventry, U.K.; www.
salinitysolutions.co.uk) signed an
agreement with Te-Tech Process
Solutions (Totton, Southampton, U.K.; www.
te-tech.co.uk) to manufacture commercial
water-purification systems based on batch
reverse-osmosis (RO). This technology,
originally characterized and developed at
the University of Birmingham (U.K.; www.
birmingham.ac.uk) and commercialized by
spin-off company Salinity Solutions, is said
to use 50% less energy and generate 80%
less waste than conventional RO, while purifying
up to 98% of the water. Co-founder,
Liam Burlace says " Batch RO is next-generation
technology, allowing for high recovery
of freshwater, which considerably reduces
energy consumption in comparison to competitive
technology. "
Salinity Solution's proprietary batch RO
process, described in a 2020 issue of DeSalinity
Solutions
salination, consists of a high-pressure feed
pump, a recirculation pump, an RO module
and a free-piston pressure exchanger
(diagram). In the pressurization phase, the
feed pump generates high pressure that is
first transferred to the recirculation solution
via the pressure exchanger. The pressurized
feed then enters the RO module. To
complete the batch, the brine exiting the
RO module flows back to the pressure exchanger
via the recirculation pump. As the
concentration inside the recirculation loop
increases over time, the feed pump will generate
a higher pressure to overcome the
increasing osmotic pressure, causing the
piston to slide to the right. When the piston
reaches the end, the pressurization phase
ends, and a purge-and-refill phase occurs.
The first unit - the SAM50 - is said to be
the world's first batch RO product manufactured
commercially. It uses any standard 8-in.
RO membrane and has a typical throughput
of 25 m3/d for a
feed with up to
6,000 parts per
million (ppm)
total dissolved
solids (TDS)
and a rejection
of 95-99.5%.
Systems that
use six RO elements
in two
housings have
a throughput of
150 m3/d.
Photochemistry boosts the yield
of chiral compounds
I
solation and purification of pure, active
enantiomers is important in the development
of active pharmaceutical ingredients
and drug products. However, recovering
the desired optical isomer from a
racemic mixture means half of the chemical
produced - the undesired isomer - will be
wasted, unless it can be recycled in some
manner. Now, researchers from the Tokyo
University of Science (Japan; www.tus.ac.jp)
have developed a system that, at least for
one important class of compounds - chiral
sulfoxides - is able to produce the desired
isomer with high efficiency. This is done by a
two-step process, as described in a recent
issue of the Journal of Organic Chemistry.
In the first step, the desired isomer is
separated from the racemic mixture in a
high-performance
liquid
chromatography
(HPLC) column containing a chiral stationary
phase. The undesired enantiomer then
passes through a photoreactor - a glass
tube containing an immobilized photocatalyst
(2,4,6-triphenylpyrrylium tetrafluoroborate)
and transparent glass beads. Irradiation
with blue light (402 nm) from a light-emitting
diode (LED) causes a rapid photoracemization
of the undesired isomer back into a racemic
mixture, which can then be recycled
back to the HPLC purification column. The
cycle can be repeated until the yield of the
desired compound is as high as desired.
The researchers demonstrated the technology
for synthesizing four enantiometrically
pure chiral alkyl aryl sulfoxides, achieving optical
purities of 98-99%. High yields (>80%)
for the desired compound are achieved after
4 to 6 cycles.
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM
JULY 2023
Edited by:
Gerald Ondrey
ORE BENEFICIATION
Last month, Torngat Metals
Ltd. (Montréal, Que.,
Canada: www.torngat
metals.com) and Metso
Corp. (Helsinki, Finland;
www.mogroup.com)
signed a contract for
large-volume, pilot-scale
processing of ore. The
focus of the agreement
is to pilot test the beneficiation
of ore extracted
from Torngat's Strange
Lake Rare Earth project
in Québec. This project
is a critical driver for the
electrification value chain,
specifically the manufacturing
of permanent magnets
for electric motors,
wind turbines and other
low-carbon technologies.
The process incorporates
advanced technologies,
including X-ray
sensor-based ore sorting,
magnetic separation
and flotation, based
on Metso's proprietary
technology. This work is
being executed in close
collaboration with GTK
Mintec, the Geological
Survey of Finland.
The first phase of work will
be completed by the end
of 2023, resulting in the
production of a rare-earth
concentrate. The next
phase of work will use the
rare-earth concentrate to
scale-up and optimize
the subsequent process
steps to produce a mixedrare-earth
solution, based
on Metso's expertise in
acid- and heat-based
minerals processing and
purification. Metso will
also provide productionscale
engineering and
offer technology and
equipment solutions for
future commercial operations
with Torngat.
NEW POLYMER
Thermal and infrared
(IR) imaging are used in
many industries, but the
materials used for this
technology (germanium
(Continues on p. 6)
5
http://www.salinitysolutions.co.uk http://www.salinitysolutions.co.uk http://www.torngatmetals.com http://www.torngatmetals.com http://te-tech.co.uk http://www.mogroup.com http://www.birmingham.ac.uk http://www.birmingham.ac.uk http://www.tus.ac.jp http://WWW.CHEMENGONLINE.COM
Chemical Engineering July 2023

Table of Contents for the Digital Edition of Chemical Engineering July 2023
