|Figure 1: Inside the Australian Synchrotron.|
(Copyright © 2015 by Australian Synchrotron. www.synchrotron.org.au/images/newsEventsPublications/)
|Adding value to brown coal research|
|By Dr David Cookson, Principal Scientist, Australian Synchrotron; and Prof. Sankar Bhattacharya and Prof. Alan Chaffee, Monash University|
|In recent years, Australian science has benefitted from access to the Synchrotron facility located in Melbourne. Dr David Cookson, Professor Sankar Bhattacharya and Professor Alan Chaffee outline some of the BCIA-funded research making use of this facility.|
|The Australian Synchrotron is one of Australia’s most important pieces of scientific infrastructure, a state-of- the-art toolbox of research techniques, about the size of a football field, located in Clayton in Melbourne’s south east. It contains a vast, circular network of interconnecting tunnels and high tech apparatus. To its users, who come from industry and academia across Australia and New Zealand, the Australian Synchrotron offers a highly intense and reliable source of malleable light, from infrared to hard X-rays, which is channelled and focused to provide new insight into the composition and behaviour of materials.|
The light beams are produced by forcing high-energy electrons to travel in a circular orbit using strong magnetic fields. The interaction of the magnetic fields with the electrons, which travel at just under the speed of light (about 300,000 km per second), creates extremely bright synchrotron light, a million times brighter than the sun, which travels into one of ten experimental workstations, called beamlines. The characteristics of the light means synchrotron-based experiments are typically more accurate, more detailed, more specific and faster than those obtained using conventional laboratory equipment.
|The Australian Synchrotron is a unique facility that allows experiments to be conducted that could not be performed anywhere else in the country. Since commencing operations in 2007, the Synchrotron has facilitated a huge diversity of research activities, ranging from medical and life sciences to advanced materials and engineering, and from earth and environmental sciences to accelerator science and synchrotron research methods. Data produced at the Australian Synchrotron has contributed to more than 2,000 publications in leading international peer-reviewed journals.|
Access to ‘beamtime’ at the Australian Synchrotron is highly competitive. Reflecting their quality and that of their work, some of the students involved in BCIA-funded research projects have been awarded beamline access as merit users, due to the innovative nature of their research and its focus on practical outcomes.
|Figure 1: PhD student Mr Tao Xu at the Department of Chemical Engineering at Monash University (funded by the BCIA and China Scholarship Council) using the Australian Synchrotron’s Infrared Spectroscopy (IR) beamline examining the evolution of surface functional groups from brown coals with temperature.|
|These include the following BCIA-funded projects supervised by professors Sankar Bhattacharya and Alan Chaffee.|
- Entrained flow gasification of brown coals
Ms Joanne Tanner, Mr Tao Xu, Ms Sunaina Dayal, and Dr Srikanth Srivats
- Catalytic synthesis of chemicals following gasification
Mr Bayzid Kabir
- Electrode stability in the presence of brown coal for Direct Carbon Fuel Cell application
Dr Adam Rady
- Chemical looping combustion
Dr Sharmen Rajendran and Mr Makarios Wong
- Chemical looping combustion
Dr Sharmen Rajendran and Mr Makarios Wong
- Activated carbons from brown coal
In the course of their research, the students have used four beamlines at the Australian Synchrotron for the following techniques.
- Infrared Spectroscopy (IR) – a non-destructive, highly sensitive technique for analysis of microscopic materials, providing information on surface chemistry at a scale of 3–8 μm.
- Powder Diffraction (PD) – for structural characterisation of powder or microcrystalline samples. The high brilliance of the synchrotron radiation makes it possible to observe changes in the pattern during chemical reactions, temperature ramps, changes in pressure, etc.
- Soft X-ray Spectroscopy (SXR) – featuring X-ray photoelectron spectroscopy, a widely used technique for determining the atomic configuration and chemistry at the surfaces of materials.
- X-ray Absorption Spectroscopy (XAS) – used to determine the ‘nearest neighbour’ environment seen by atoms of a specified element in a material.
|Typically, these experiments run continuously for up to 72 hours. A successful outcome requires careful pre-planning and the participation of several researchers, along with their supervisor. The information gained from these experiments is combined with standard laboratory based analysis using Gas Chromatography-Mass Spectrometry, Thermogravimetric Analysis and Scanning Electron Microscopy.|
The research topics that have been investigated include the following.
- The structural changes occurring inside coal or biomass during drying, pyrolysis or gasification under realistic operating conditions, and the implications for improved design of large scale gasifiers.
- Changes in coal ash behaviour and their relation to viscosity of slags during entrained flow gasification.
- The evolution of gaseous species and trace elements during pyrolysis and gasification, and the implications for the design of gas clean-up systems.
- Interactions between electrolytes and coal minerals under conditions representative of Direct Carbon Fuel Cell operation.
- Interactions between coal minerals and oxygen carriers under conditions representative of Chemical Looping combustion.
- Changes in catalysts during chemicals synthesis from fuel gas following gasification, providing insights into new catalyst design for improved working life.
- Changes in the surface chemistry of activated carbons as a result of different processing conditions.
- Determining the precise structure of new materials with CO₂ capture potential.
- In-situ observation of changes in the crystallinity of CO₂ adsorbents that develop during use.
|Access to the Australian Synchrotron has allowed brown coal researchers, including those at Monash University described above, to undertake detailed investigations that would otherwise not have been possible. The insights that have been achieved have contributed substantially to efforts to improve the applications of Victorian brown coal.|
In addition, the students involved have gained invaluable training that will be of benefit to their careers. Two of the students are now working as scientists in the US and Sweden, and another will soon start work in Germany.
Australia’s synchrotron: Open for international business
The Industry Support Team at the Australian Synchrotron is dedicated to supporting industrial users. By drawing on their own expertise and that of their Synchrotron colleagues, the team facilitates the design and execution of cutting-edge experiments and analysis to help solve pressing industrial problems, reduce technical risk and unlock the potential of new products and processes for industry clients. Further information on how the Australian Synchrotron can effectively and confidentially support your industrial research, please visit Australia’s Synchrotron website at industry.synchrotron.org.au.
|Figure 2: Inside the Australian Synchrotron storage ring, where bunches of electrons travel at close to the speed of light. (Copyright © 2015 by Australian Synchrotron)|
|Figure 3: Researchers in a beamline station at the Australian Synchrotron. (Copyright © 2015 by Australian Synchrotron)|