Daniele Fregonese, Senior Vice President of Sales and Marketing at Advanced Energy Minerals, explains the benefits of the company’s sustained ultra-high purity aluminum trioxide SupALOX ™.
Powered by hydroelectricity, using our patented and patented chlorine-crystal leaching (CLCP) manufacturing process and using local raw materials, the Cap-Chat plant has an industry-leading low-carbon footprint. It produces almost zero waste and can supply up to 99.999% pure alumina (5N HPA) at globally competitive prices. It is particularly well located for delivery to North American and European markets.
We acquired the Cap-Chat plant from Orbite Technologies in 2020. It was previously built with a design capacity of 1000 tpa HPA, but encountered engineering deficiencies during commissioning. After acquiring it, we reorganized the plant to eliminate these shortcomings and subsequently successfully completed the commissioning of the plant.
The CLCP process was developed at our Center for Technical Development (TDC) in Montreal. Equipped with state-of-the-art C $ 8 million laboratory equipment and equipped with highly qualified research engineers and scientists, TDC gives us comprehensive, in-house research and development capabilities to guide our process and product development activities. The process is suitable for the production of HPA from a number of aluminum raw materials and is protected by a number of international patents. TDC, its know-how and patents were acquired as a package with the Cap-Chat plant.
What is the use of ultra high purity aluminum trioxide?
HPA is valued for its excellent properties in terms of chemical stability, very high melting point; high mechanical strength and hardness (especially as sapphire); and good thermal conductivity but high electrical insulation. It accepts several crystal structures, such as alpha (α), beta (β) and gamma (γ). The specific surface area of α-HPA is low and very resistant to high temperatures and is inert, with almost no catalytic activity. While γ-alumina has excellent dispersion and a higher specific surface area, it is inert and provides high activity. It is more often used as a support for catalysts and adsorbents.
HPA is usually sold in powder or pellet form (compacted powder in the form of a ‘washer’), depending on the end use, as each application has different physical and chemical tolerances. The powder has a particle size that is usually measured in microns (μm); however, some ultrafine powders can be measured in nanometers (nm).
Pellets (or washers) are used to make synthetic sapphire and are designed to maximize HPA density. Equipment that melts HPA into sapphire can maximize production volume per production. Purity is also essential, as any impurities can affect the transparency or conductivity of the sapphire produced and can also reduce the yield of a continuous sapphire crystal. The main uses of synthetic sapphire are as a substrate in semiconductors, in particular light emitting diodes (LEDs), and in high-performance optical and photonic applications.
Powders have a wide range of applications in advanced ceramic applications (eg for additive manufacturing) and are increasingly used in high performance batteries where HPA is:
- It is already well used as a ceramic coating for the polymer separator in lithium-ion batteries;
- Seeing the emerging use as a coating for anodes and cathodes: and,
- Development of potential applications in solid electrolytes.
Depending on the final application, the powders must be produced according to a specific morphological specification. The particle size can be controlled both at the crystal growth stage and by subsequent grinding (although the latter requires careful control to avoid contamination by the grinding medium).
Currently, HPA’s demand for sapphire production, especially for its use in LED lighting, dominates the market. However, demand from the battery sector is expected to grow rapidly amid the global transition to electric vehicles (EVs).
What is SupALOX висока high purity alumina?
We produce SupALOX ™ high-purity alumina as α-phase, usually 5N pure (99.999%) alumina2Oh3), which we can then adapt to the specific requirements of each client for:
- Particle size – as a powder in the range of particle size distribution, up to a minimum of D50 from 200 nm;
- Sealing – as sintered washers up to a maximum specific gravity of 3.8; and
- Doping – for example for the production of spinel.
The 5N purity of SupALOX ™ HPA, measured in all significant impurities, is among the highest purity currently available on the market and is unmatched by all but very few existing suppliers.
The conventional technological path for the production of high-purity alumina is the alkoxide process, which first reacts with the aluminum metal with alcohol. It then reacts with the resulting alkoxide with water to give alumina. Aluminum metal is an expensive raw material and is usually highly carbon. In a recent report, CICERON shades of green has indicated that the typical carbon footprint of HPA produced by the alkoxide process is 12.3 tCO2e / t HPA.
Our CLCP technology route for the production of SupALOX ™ HPA is very different, as our raw materials and energy supplies are both competitively priced and with extremely low carbon footprints. Internal calculations, which have yet to be independently verified, show that the resulting carbon footprint of SupALOX ™ HPA is less than 1.5 tCO2e / t HPA, i.e. less than 12% of the carbon footprint of HPA produced by the conventional alkoxide process.
Hydrochloric acid, another major input to our CLCP process, is recycled many times in the process before being disposed of, primarily in the form of aluminum chloride, which we sell as a by-product for use in the water treatment industry.
Therefore, SupALOX ™ ultra-high purity alumina offers incredible benefits for consumers looking for alumina with the highest purity and environmental performance.
Future research and development for our CLCP process
We are actively researching and developing improvements and extensions to our CLCP process and product offering. Currently, our activities are focused on three areas:
- Apply and develop knowledge from the Cap-Chat plant to incorporate a number of process and value improvements into our CLCP process. We recently completed a feasibility study for a second manufacturing plant located in the UK with financial support from the UK Government Automotive Transformation Fund. This work has allowed us to significantly improve this design of the next generation. This will inform our plans not only for the United Kingdom, but also for the expansion of the Cap-Chat plant and the establishment of plants elsewhere;
- Exploring ways to increase our CLCP process for the production of powders and suspensions from nanosized (<10 nm) HPA particles and other high-purity aluminum compounds, especially for battery applications. We are partnering with a leading supplier of natural graphite active anode material as part of this work; and
- Development of a new form of HPA that is expected to offer significant performance gains to synthetic sapphire manufacturers.
This strong focus on research and development supports our goal of becoming a leading, highly customer-focused supplier of ultrapure HPA and related industrial minerals, delivered to the highest standards of environmental performance and social governance.
Please note that this article will also appear in the tenth edition of ours quarterly publication