Chemical Engineering December 2014 - 19

Newsfront
is to achieve an operating life of five
years of stable operation without
increasing cell voltage and loss of
efficiency, which is better than traditional
lead anodes, he says.
Meanwhile, in February 2014,
Electrometals Technologies, Ltd.
(Gold Coast, Queensland, Australia;
www.electrometals.com) announced
plans to design larger " emew " cells
that will lower the installed cost,
double production capacity per cell,
and nearly triple the productive
footprint of its standard cells. Unlike
the planar electrodes used in
conventional EW cells, emew cells
use concentric cylindrical electrodes.
This design is said to " significantly "
enhance mass transfer, thereby improving
cell efficiency.
Primary aluminum production
Today, aluminum continues to be
manufactured by the 19th-century
Hall-Héroult process, whereby alumina
(Al2O3) is dissolved in molten
salts and electrolyzed. As such, the
process is very energy intensive,
both because of the high temperatures
involved and the electricity
needed to run the electrolyzer. Besides
high energy costs, the high
operating costs are compounded
because the process uses large
amounts of graphite or coke that
are used for the anodes, and which
are consumed during the electrolysis
to make CO2 - in itself another
drawback of primary Al production.
A different approach to primary
Al production is being developed
by the Gas Technology Institute
(GTI; Des Plaines, Ill.; www.
gastechnology.org), with support
from the U.S. Dept. of Energy's
(Washington, D.C.; www.energy.
gov) Advanced Research Projects
Agency-Energy (ARPA-E; www.
arpa-e.energy.gov). GTI's project is
one of about 18 in ARPA-E's Modern
Electro/Thermochemical Advances
in Light Metal Systems (METALS)
program, which aims to find cost-effective
and energy-efficient manufacturing
techniques to process and
recycle light metals (Al, Ti, Mg) for
lightweight vehicles and aircraft.
GTI is developing a continuously
operating cell (Figure 2) that proMagnetically
coupled Roots pump
combines a magnetic coupling with
category 2 or 3 explosion protection
OktaLine®
ATEX
n explosion safety due to reliable construction and temperature
monitoring - installation without additional flame arrester possible
n Hermetically sealed (leakrate < 10-6 Pa m3/s) - risk of zone
entrainment is minimized
n AteX protection in case of passive rotation
n flexible application - pump can start against atmospheric pressure
n Pressure surge resistance according to en 1333, Pn level 16
Are you looking for a perfect vacuum solution?
Please contact us:
Pfeiffer Vacuum GmbH · Headquarters/Germany
t +49 6441 802-0 · f +49 6441 802-1202
info@pfeiffer-vacuum.de · www.pfeiffer-vacuum.com
Circle 16 on p. 60 or go to adlinks.che.com/50983-16
ChemiCal engineering www.Chemengonline.Com DeCemBer 2014 19
14.10.31_Chemical_Engineering_OktaLine_ATEX_GB_117,5x187,3.indd 1
31.10.14 16:48
duces Al powder with potential
cost savings of 44% compared to
the conventional Hall-Héroult process.
Conventional Al production
is done by pumping huge electrical
currents into a vat of molten aluminum
dissolved in mineral salts
at up to 2,000°F. In contrast, GTI's
DEEE technology (dual electrolyte
extraction electro-refinery) operA
P Assion for PerfeCtion
ates at nearly room temperature
using recyclable solvents to dissolve
the ore. Liquid-liquid extraction is
used with the aid of electro-osmotic
drag in an electrolyzer cell. Al+3
ions in an acid solution in the cathode
cell migrate through a bipolar
membrane to the anode, where they
are reduced to Al metal.
In the first phase of the project
http://www.electrometals.com http://www.gastechnology.org http://www.energy http://arpa-e.energy.gov http://www.pfeiffer-vacuum.com http://adlinks.che.com/50983-16 http://www.Chemengonline.Com
Chemical Engineering December 2014

Table of Contents for the Digital Edition of Chemical Engineering December 2014
