Sustainably manufactured
ultra-high purity alumina
in Canada
Daniele Fregonese, SVP for Sales and Marketing at Advanced Energy Minerals, explains the benefits of the company’s SupALOX™ sustainably manufactured ultra-high purity alumina
Advanced Energy Minerals (AEM) manufacture ultra-high purity alumina (HPA) at our full-scale production plant at Cap-Chat, Quebec, Canada, which we market under our SupALOX™ brand. Powered by hydroelectricity, using our patent-protected and proprietary Chlorine Leach - Crystalline Purification (CLCP) production process and utilising a locally sourced feedstock, the Cap-Chat plant has an industry-leading low carbon footprint. It produces nearly zero waste and can deliver up to 99.999% pure alumina (5N HPA) at globally competitive prices. It is particularly well placed to supply North American and European markets.
We acquired the Cap-Chat plant from Orbite
Technologies in 2020. It had previously been built
with a design capacity of 1,000 tpa of HPA but
encountered engineering shortcomings during
commissioning. Having acquired it, we have reengineered the plant to remove those shortcomings
and have subsequently completed the plant’s
commissioning successfully.
The CLCP process was developed at our Technical
Development Centre (TDC) in Montreal. Equipped
with C$8m worth of advanced laboratory equipment
and staffed by highly qualified research engineers
and scientists, the TDC gives us a comprehensive, in-house research and development capability to
lead our process and product development activities.
The process is suitable for manufacturing HPA from
a range of aluminous feedstocks and is protected by
a range of international patents. The TDC, its know-how and the patents were all acquired as a package
with the Cap-Chat plant.
What are the uses of high purity alumina?
HPA is valued for its excellent properties in terms
of chemical stability, very high melting point; high
mechanical strength and hardness (particularly as
sapphire); and good thermal conductivity but high
electrical insulation. It takes on several crystalline
structures, such as alpha (α), beta (β) and gamma (γ).
The specific surface area of α-HPA is low, and it is
very resistant to high temperature and inert, having
almost no catalytic activity. Whereas γ-alumina has excellent dispersion and a higher specific surface
area, it is inert and provides high activity. It is more
commonly used as a catalyst support and adsorbent.
HPA is generally marketed in either powder or
pellet (compacted powder in a ‘puck’ shape) form,
depending upon the end-use, as each application
has different physical and chemical tolerances. The
powder has a particle size typically measured in
microns (μm); however, certain ultra-fine powders
may be measured in nanometres (nm).
Pellets (or pucks) are used to manufacture synthetic
sapphire and designed to maximise the HPA’s density. The equipment that melts the HPA into
sapphire can maximise production volume from
a single production run. Purity is also essential
because any impurities may impact the transparency
or conductivity of the sapphire produced and may
also reduce the yield of continuous sapphire crystal.
The primary uses for synthetic sapphire are as a
substrate in semiconductors, particularly lightemitting diodes (LEDs), and in high-performance
optical and photonic applications.
Powders have a range of uses in advanced ceramic
applications (e.g., for additive manufacturing) and
have growing uses in high-performance batteries,
where HPA is:
• Already in well-established use as a ceramic coating to the polymer separator in lithium-ion batteries;
• Seeing emerging use as a coating to anodes and cathodes: and,
• Exhibiting potential uses in solid-state electrolytes.
• Already in well-established use as a ceramic coating to the polymer separator in lithium-ion batteries;
• Seeing emerging use as a coating to anodes and cathodes: and,
• Exhibiting potential uses in solid-state electrolytes.
Depending on the end-use application, powders
need to be produced to a particular morphological
specification. Particle size can be controlled both at
the crystal-growing stage and via subsequent milling
(although the latter requires careful control to avoid
contamination by the grinding media).
Currently, demand for HPA for sapphire production,
especially for its use in LED lighting, dominates
the market. However, the demand from the battery
sector is expected to grow rapidly on the back of the
global transition to electric vehicles (EVs).
What is SupALOX™ high purity alumina?
We manufacture SupALOX™ high purity alumina
as α-phase, typically 5N pure (99.999%) aluminium
oxide (Al2
O3
), which we can then tailor to each
customer’s specific requirements for:
• Particle size – as a powder in a range of particle size distributions, down to a minimum D50 of 200 nm;
• Densification – as sintered pucks to a maximum specific gravity of 3.8; and
• Doping – for example, for the manufacture of spinel.
• Particle size – as a powder in a range of particle size distributions, down to a minimum D50 of 200 nm;
• Densification – as sintered pucks to a maximum specific gravity of 3.8; and
• Doping – for example, for the manufacture of spinel.
SupALOX™ HPA’s 5N purity, measured across all
significant impurities, is among the highest purity
currently available in the market and is unmatched by
all but very few existing suppliers.
The conventional process route for producing high
purity alumina is the alkoxide process, which first
reacts aluminium metal with an alcohol. It then reacts
the resulting alkoxide with water to produce alumina.
The conventional process route for producing high
purity alumina is the alkoxide process, which first
reacts aluminium metal with an alcohol. It then reacts
the resulting alkoxide with water to produce alumina.
The aluminium metal feedstock is expensive and
typically highly carbon-intensive. In a recent report,
CICERO Shades of Green has indicated that the
typical carbon footprint of HPA produced by the
alkoxide process is 12.3 tCO2
e/t HPA.
Our CLCP process route for manufacturing
SupALOX™ HPA is very different, with our feedstock
and energy supply being both competitively priced
and having extremely low carbon footprints. In-house
calculations, yet to be independently verified, indicate
that the resulting carbon footprint of SupALOX™
HPA is less than 1.5 tCO2
e/t HPA, i.e., less than 12%
of the carbon footprint of HPA manufactured by the
conventional alkoxide process route.
Hydrochloric acid, another essential input to our
CLCP process, is recycled many times within the
process before being discharged, predominantly in the form of aluminium chloride, which we sell as a
by-product for use in the water treatment industry.
SupALOX™ HPA, therefore, offers compelling
benefits to users seeking alumina with leading-edge
purity and environmental credentials.
Future research and developments for our CLCP process
We actively research and develop improvements and
extensions to our CLCP process and product offering.
Our activities are currently focused on three areas:
• Applying and developing learnings from the CapChat plant to incorporate a range of process and value engineering improvements in our CLCP process. We recently completed a feasibility study for a second production plant located in the UK with financial support from the UK Government’s Automotive Transformation Fund. This work enabled us to advance this next generation design substantially. It will inform our plans not just for the UK but also for expanding the Cap-Chat plant and establishing plants in other locations;
• Researching ways of augmenting our CLCP process to produce powders and suspensions of nano-sized (<10 nm) particles of HPA and other high purity compounds of aluminium, particularly for battery applications. We are partnering with a leading supplier of natural graphite active anode material as a part of this work; and
• Developing a new form of HPA, which is expected to offer significant productivity gains to manufacturers of synthetic sapphire.
• Applying and developing learnings from the CapChat plant to incorporate a range of process and value engineering improvements in our CLCP process. We recently completed a feasibility study for a second production plant located in the UK with financial support from the UK Government’s Automotive Transformation Fund. This work enabled us to advance this next generation design substantially. It will inform our plans not just for the UK but also for expanding the Cap-Chat plant and establishing plants in other locations;
• Researching ways of augmenting our CLCP process to produce powders and suspensions of nano-sized (<10 nm) particles of HPA and other high purity compounds of aluminium, particularly for battery applications. We are partnering with a leading supplier of natural graphite active anode material as a part of this work; and
• Developing a new form of HPA, which is expected to offer significant productivity gains to manufacturers of synthetic sapphire.
This heavy emphasis on research and development
supports our aim to become a leading, highly customer-focussed supplier of ultra-pure HPA and
related industrial minerals delivered to the highest
standards of environmental performance and social
governance.
Daniele Fregonese
SVP for Sales & Marketing
Advanced Energy Minerals Limited
+1 418 786 5492
dfregonese@aem-international.com
www.supalox.com
