Assessing lignite fractionation as a precursor to the production of fine chemicals

Victorian lignite’s are extremely heterogeneous materials. A wide range of coal processing technologies are compromised by the presence of undesirable components in their feedstock. For example, approximately 1/3 of dry lignite is converted to tar during pyrolytic processing and traditional solvent extraction approaches on brown coals suffer from their low yield and contamination of target fine chemicals.  This project will investigate the pre-concentration afforded by physical, chemical and thermal separation of the coal fractions prior to solvent extraction or further processing. Some potential products from Victorian lignite fractions include:

• Humics (alkali extraction) a agricultural products
• Waxes and Resins a polyphenolics and edible coatings and naturally derived adhesives
• Clay is a potential target for natural pre-concentration of rare earths
• Tars (by-products from high-temperature coal charing) a carbon fibre, ultra-high purity carbons

There is significant potential to incorporate CO2 use into this project, particularly the use of supercritical CO2 or bicarbonate solutions as solvents for extracting fine chemicals or precursors. This project could involve collaboration with RMIT to investigate the different qualities of carbon fibre formed from young lignin derived from woody biomass with ancient lignins derived from Victorian Brown coal.

Available resources

• Extensive knowledge and rare SECV reports describing the productions of fine chemicals from Victorian Brown Coal
• Autoclaves, standard reaction vessels and a tube furnace
• Extensive analytical equipment for the characterisation of feed stocks, intermediates and products.

Potential industrial impact: Reduce the commercial and technical risks inherent in new Brown Victorian Brown coal industries.
Potential industry partners: Brown Coal Innovation Australia
Technology Readiness Level 4. The individual processes proposed by this project are available commercially but may not have been used for Victorian lignite.