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A method of depolymerizing coal includes preparing a high temperature depolymerizing medium consisting of heavy hydrocarbon oils and mixing it with coal to form a mixture, performing an optional first distillation at a temperature below 250° C. to recover naphthalene, heating the mixture to a temper

A method of depolymerizing coal includes preparing a high temperature depolymerizing medium consisting of heavy hydrocarbon oils and mixing it with coal to form a mixture, performing an optional first distillation at a temperature below 250° C. to recover naphthalene, heating the mixture to a temperature between 350° C. and 450° C. to create a digested coal, centrifuging the digested coal to remove ash and obtain a centrate, and distillation of the centrate into separate fractions. The high temperature depolymerizing medium may be a heavy hydrocarbon with a hydrogen to carbon (H/C) ratio higher than 7.0% and may include liquids chosen from the group consisting of: coal tar distillate, decant oil, anthracene oil, and heavy aromatic oils. The high temperature depolymerizing medium may be blended with an oil, preferably with H/C ratio higher than 10.0%, such as soybean oil, other biomass derived oil, lignin, petroleum oil, pyrolysis oil such that the overall hydrogen-to-carbon mass ratio in a digestion reactor is over 7.0% for the mixture of depolymerizing medium and coal. The depolymerized coal is an aromatic liquid that can itself be, either wholly or in part, a depolymerizing medium so that the process can be repeated.

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1. A method of depolymerizing coal, comprising: preparing a high temperature depolymerizing medium consisting of heavy hydrocarbon oils and mixing it with coal to form a mixture, wherein the high temperature depolymerizing medium is a heavy hydrocarbon with H/C ratio higher than 7.0%;performing a fi

1. A method of depolymerizing coal, comprising: preparing a high temperature depolymerizing medium consisting of heavy hydrocarbon oils and mixing it with coal to form a mixture, wherein the high temperature depolymerizing medium is a heavy hydrocarbon with H/C ratio higher than 7.0%;performing a first distillation to recover naphthalene;heating the mixture to a temperature of at least 350° C. to create a digested coal slurry; andcentrifuging the slurry to produce a centrate liquid with ash content less than 0.5% by mass. 2. The method of claim 1, wherein the high temperature depolymerizing medium consists of liquids chosen from the group consisting of: coal tar distillate, decant oil, anthracene oil, and heavy aromatic oils. 3. The method of claim 1, wherein the high temperature depolymerizing medium is blended with an oil, with H/C ratio higher than 10.0%, chosen from the group consisting of: soybean oil, pine tar, aromatic petroleum distillate, biomass gasification tar, biomass pyrolysis tar, and oils where the overall hydrogen-to-carbon mass ratio in a digestion reactor is over 7.0% for the mixture of high temperature depolymerizing medium and coal. 4. The method of claim 1, wherein the coal is dried via air drying or heating to above 100° C. prior to exposing the coal to the depolymerizing medium. 5. The method of claim 1, in which the centrate liquid, either wholly or after being separated into different fractions, is used as the depolymerizing medium in subsequent executions of the method. 6. The method of claim 1, wherein the mixture comprises a ratio of 1 part coal to a range of at least 1.5 parts to 2.5 parts of depolymerizing medium. 7. The method of claim 1, wherein centrifuging is done at a temperature of at least 100° C., or above the softening temperature of the liquid constituents of the coal digest. 8. The method of claim 1, wherein the coal is a low rank non-coking coal with ash below 5% by mass, further comprising distilling the low rank non-coking coal to produce a pitch. 9. The method of claim 8, further comprising converting the pitch to a solid carbon coke in an oxygen-depleted environment at above 600° C., and co-producing thermally liberated volatile molecules. 10. The method of claim 8, wherein the coal is selected such that it has less than 6.0% ash. 11. The method of claim 1, further comprising, distilling the centrate liquid to further separate it into different fractions according to boiling point. 12. The method of claim 9, wherein said solid carbon coke is selected from the group consisting of: a metallurgical grade coke, a foundry grade coke, feedstock for other furnace grade carbon such as injection carbon, charge carbon or recarburizer carbon. 13. The method of claim 1, wherein the depolymerizing medium has an H/C ratio of less than 0.70, and the coal is selected such that its H/C ratio is greater than 0.75, thus resulting in an overall digest with H/C ratio greater than 0.70 on an ash-free basis. 14. The method of claim 13, wherein a bio-oil is not present, and hydrogenation is not used to enhance the hydrogen content of the depolymerizing medium. 15. The method of claim 1, further comprising, filtering the slurry to produce a centrate liquid with ash content less than 0.5% by mass. 16. The method of claim 1, wherein the ash content is less than 0.2% by mass. 17. The method of claim 1, wherein the high temperature depolymerizing medium is blended with an oil selected from the group consisting of: a biomass-derived oil, a lignin, a petroleum oil, a pyrolysis oil, and an oil from vegetable matter. 18. The method of claim 1, further comprising, distilling the centrate liquid to produce a pitch residue with hydrogen content between 4.0% and 5.0%, and with a softening temperature of about 110° C. and ash level less than 0.5% by mass.