Enzymantic Conversion of Coal to Liquid Fuels

Richard Troiano

关键词: ABSORPTION;    AROMATICS;    BITUMINOUS COAL;    CLEAVAGE;    COAL;    ENERGY FACILITIES;    ENERGY MODELS;    ENVIRONMENTAL IMPACTS;    ENZYMES;    FUNGICIDES;    GRINDING;    HYDROCARBONS;    LIGNIN;    LIQUID FUELS;    MANGANESE;    PARTICLE SIZE;    PEROXIDASES;    PHANEROCHAETE;    SPECTRA;    TARTRATES;   

DOI  :  10.2172/1033555
RP-ID  :  None
PID  :  OSTI ID: 1033555
Others  :  TRN: US201203%%195

美国|英语

来源: SciTech Connect

【 摘 要 】

The work in this project focused on the conversion of bituminous coal to liquid hydrocarbons. The major steps in this process include mechanical pretreatment, chemical pretreatment, and finally solubilization and conversion of coal to liquid hydrocarbons. Two different types of mechanical pretreatment were considered for the process: hammer mill grinding and jet mill grinding. After research and experimentation, it was decided to use jet mill grinding, which allows for coal to be ground down to particle sizes of 5 {mu}m or less. A Fluid Energy Model 0101 JET-O-MIZER-630 size reduction mill was purchased for this purpose. This machine was completed and final testing was performed on the machine at the Fluid Energy facilities in Telford, PA. The test results from the machine show that it can indeed perform to the required specifications and is able to grind coal down to a mean particle size that is ideal for experimentation. Solubilization and conversion experiments were performed on various pretreated coal samples using 3 different approaches: (1) enzymatic - using extracellular Laccase and Manganese Peroxidase (MnP), (2) chemical - using Ammonium Tartrate and Manganese Peroxidase, and (3) enzymatic - using the live organisms Phanerochaete chrysosporium. Spectral analysis was used to determine how effective each of these methods were in decomposing bituminous coal. After analysis of the results and other considerations, such as cost and environmental impacts, it was determined that the enzymatic approaches, as opposed to the chemical approaches using chelators, were more effective in decomposing coal. The results from the laccase/MnP experiments and Phanerochaete chrysosporium experiments are presented and compared in this final report. Spectra from both enzymatic methods show absorption peaks in the 240nm to 300nm region. These peaks correspond to aromatic intermediates formed when breaking down the coal structure. The peaks then decrease in absorbance over time, corresponding to the consumption of aromatic intermediates as they undergo ring cleavage. The results show that this process happens within 1 hour when using extracellular enzymes, but takes several days when using live organisms. In addition, live organisms require specific culture conditions, control of contaminants and fungicides in order to effectively produce extracellular enzymes that degrade coal. Therefore, when comparing the two enzymatic methods, results show that the process of using extracellular lignin degrading enzymes, such as laccase and manganese peroxidase, appears to be a more efficient method of decomposing bituminous coal.