KONTAN.CO.ID – JAKARTA.Research and Development Center for Mineral and Coal Technology (Tekmira) Research and Development Agency of the Ministry of Energy and Mineral Resources initiated research on battery anodes from coal by converting coal into high-value pitch raw materials.
The research, which was carried out by the Research and Development Group (KP3) of Coal Processing and Utilization Technology, aims to support the downstream program of coal into high value synthetic graphite raw materials.This activity is focused on making carbon precursors from the residue of coal tar distillation as energy storage materials.
KP3 Coordinator for Coal Processing and Utilization Technology, Slamet Handoko, explained that graphite is the main raw material for battery anodes which are commonly used in batteries for electronic equipment such as batteries for cell phones, laptops and electric vehicles.This material is high performance and has a fast fill capacity and a long life.
Currently, about 83% of the world’s natural graphite supplies come from China and Brazil.However, not all natural graphite can be used as a battery anode, due to its purity and crystal size qualities.
Synthetic graphite has a homogeneous purity and crystal size.Unfortunately, the conventional process of making synthetic graphite from petroleum is still expensive, reaching 10 times the cost of processing natural graphite.
Although the price of synthetic graphite has skyrocketed, the proportion of synthetic graphite used as battery anode has not decreased.To reduce production costs, usually synthetic graphite is mixed with processed natural graphite orspherical graphite.
“As of 2014, the proportion of synthetic graphite has reached 33% -40% and is predicted to continue to increase along with the increasing demand for electric car batteries,” Slamet continued in a press release on the Ministry of Energy and Mineral Resources website quoted by Kontan.co.id, Monday (11/1) .
Based on data published by electric car manufacturer Tesla, the demand for natural graphite is estimated to increase annually by 154%.These results place graphite as the most sought after mineral in the future.
Therefore, synthetic graphite research needs to be done to anticipate the boom in demand, especially since Indonesia does not have an economical natural graphite mine.
Low rank coal in Indonesia is very abundant and has a large enough potential to be used as a carbon precursor in the manufacture of battery anodes.In general, coal produces hydrocarbons when burned with oxygen and produces heat.
However, if the coal is heated in the absence of oxygen, there will be hydrocarbons in the form of coal tar which can be further processed into pitch.The process of making coal tar is known as pyrolysis, while the processing of tar into pitch is usually through distillation.These two processes have been researched and mastered by researchers at the Research and Development Center for Tekmira, Ministry of Energy and Mineral Resources.
However, not all parts of the pitch can be made into synthetic graphite, so it needs to be modified and extracted using a solvent.Only about 30% -40% of the pitch can be extracted and can then be used as a carbon precursor for synthetic graphite manufacture.The extracted product is often referred to as themesophase pitch, because it contains 100% carbon which can be converted into graphite.
The head of the Phiciato Research Team explained that the conventional synthetic graphite manufacturing process, whether using petroleum or coal, must go through a process at an extreme temperature of around 2,000–3,000 degrees Celsius
This condition is difficult to apply economically on an industrial scale.With the help of a catalyst, the process temperature can be lowered to close to 1,000 degrees Celsius.Observations with X-Ray Diffraction show that synthetic graphite can be formed at a temperature of 1,200 degrees Celsius with the help of an Fe-based catalyst (Ferrum).
“The key to success is influenced by two aspects, namely the effectiveness of making mesophase and choosing the type of catalyst. Currently, the research team is still focusing on making mesophases and in the future will develop suitable and economical catalysts,” said Phiciato.
This Young Researcher of the Research and Development Center for Tekmira explained that in principle synthetic graphite can be synthesized from all types of carbon materials such as biomass, soot, charcoal, and industrial waste, as long as it has a suitable catalyst medium and guarantees the availability of supplies.
When compared with biomass, the fixed carbon content or fixed-carbon in coal is on average 2-3 times the biomass.This underlies the selection of coal and its derivatives as an economical carbon precursor.The higher the carbon content will certainly have an impact on the better the economics of the graphitization process.