Abstract: Embodiments of the present disclosure generally relate to the recovery and extraction of rare earth elements. More specifically, embodiments of the disclosure relate to methods for separating rare earth elements from coal, coal by-product(s), and/or coal-derived product(s). In an embodiment, a method of removing rare earth elements from a coal-derived product is provided. The method generally includes introducing supercritical CO2 to the coal ash to form a first mixture, introducing a first acid to the first mixture to form a second mixture, and removing a first composition from the second mixture, the first composition comprising the one or more rare earth elements.

Abstract: Embodiments of the present disclosure generally relate to the recovery and extraction of rare earth elements. More specifically, embodiments of the disclosure relate to methods for separating rare earth elements from coal, coal by-product(s), and/or coal-derived product(s). In an embodiment, a method of removing rare earth elements from a coal-derived product is provided. The method generally includes introducing supercritical CO2 to the coal ash to form a first mixture, introducing a first acid to the first mixture to form a second mixture, and removing a first composition from the second mixture, the first composition comprising the one or more rare earth elements.

Abstract: Use of chemical pretreatment agents on the subsequent enzymatic conversion of coal is described. As an example, fungal manganese peroxidase (MnP) produced by the agaric white-rot fungus Bjerkandera adusta, where the enzyme MnP has little effect on the untreated coal controls, was investigated. The nature of pretreatment agents and their applied concentrations were found to have significant impact on subsequent enzymatic conversion of coal. Four agents were investigated: HNO3, catalyzed H2O2, KMnO4, and NaOH. Hydrogen peroxide was found to generate the greatest quantity of total organic carbon from the coal samples employed. Combined chemical and enzymatic treatment of coal is appropriate for enhanced depolymerisation of coal and coal-derived constituents and results in chemically heterogeneous and complex liquefaction products like humic and fulvic acids, which will have important ramifications in the generation of liquid and gaseous fuels from coals as nonpetroleum-derived fuel alternatives.

Abstract: Use of chemical pretreatment agents on the subsequent enzymatic conversion of coal is described. As an example, fungal manganese peroxidase (MnP) produced by the agaric white-rot fungus Bjerkandera adusta, where the enzyme MnP has little effect on the untreated coal controls, was investigated. The nature of pretreatment agents and their applied concentrations were found to have significant impact on subsequent enzymatic conversion of coal. Four agents were investigated: HNO3, catalyzed H2O2, KMnO4, and NaOH. Hydrogen peroxide was found to generate the greatest quantity of total organic carbon from the coal samples employed. Combined chemical and enzymatic treatment of coal is appropriate for enhanced depolymerisation of coal and coal-derived constituents and results in chemically heterogeneous and complex liquefaction products like humic and fulvic acids, which will have important ramifications in the generation of liquid and gaseous fuels from coals as nonpetroleum-derived fuel alternatives.