Herein, from Amoco, in Illinois, is more confirmation that Coal can be productively converted into liquid hydrocarbon fuels.
One statement in the full Disclosure, similar in content to those in other United States Patents we have brought to your attention, jumped out at us:
"Pretreatment of low-rank coals prior to liquefaction is well known in the industry."
In what "industry", and where, in the United States of America, is the "liquefaction" of any coal, much less "of low-rank coals ... well known"?
Troublesome questions aside, consider that, nearly two decades ago, both the petroleum industry and our own United States Government knew enough about converting Coal into liquid hydrocarbons to expound on methods for treating raw feeds of low-rank Coals; methods which make Coal more suitable for such conversion into liquid hydrocarbons.
Comment follows excerpts from:
"United States Patent 5,228,982 - Liquefaction of Decarboxylated Carbonaceous Solids
Date: July, 1993
Inventor: Charles Scouten, et. al., Illinois
Assignee: Amoco Corporation, Chicago
Abstract: A composition consisting essentially of a carbonaceous solid containing at least one carboxyl group is heated with subcritical liquid water at decarboxylation conditions including a temperature of at least about 300 degrees F to substantially decarboxylate the solid, thereby producing a stream comprising a decarboxylated solid and water. The water is separated from the decarboxylated solid prior to liquefying the solid.
Claims: A liquefaction process, comprising the steps of: heating a composition consisting essentially of a carbonaceous solid containing at least one carboxyl group with subcritical liquid water to ... substantially decarboxylate said solid thereby producing a stream comprising a decarboxylated carbonaceous solid and water; separating a substantial portion of said water from said decarboxylated carbonaceous solid; and liquefying said decarboxylated carbonaceous solid to produce a hydrocarbon-containing liquid.
A process ... wherein said carbonaceous solid comprises coal.
(And) wherein a portion of the hydrocarbon containing liquid is recycled to liquefy the decarboxylated, demineralized carbonaceous solid.
(H)ydroliquefying said decarboxylated, demineralized coal to produce a coal-derived liquid; and ... recycling a portion of said coal-derived liquid.
Background: Low-rank coals are emerging as preferred feedstocks for coal liquefaction.
However, low-rank coals present special problems in coal liquefaction. (M)etals bound as the salts of ... carboxylic acids are not effectively removed by conventional coal cleaning methods, and therefore can be liberated during liquefaction. This can result in the need for a de-asher to reduce high ash load. Moreover, once liberated, these metals can attack and deactivate the supported catalysts typically used to promote liquefaction of the coal.
Pretreatment of low-rank coals prior to liquefaction is well known in the industry. Most of these pretreatment processes are designed to address the problem of how to handle alkaline earth metals, particularly calcium, which are contained in the coal.
It has been discovered that alkaline earth metal deposits, which form during liquefaction of low-rank coal, can be avoided by converting these metals to a salt which will remain stable during liquefaction.
Summary: In its broadest aspect, the present invention is a ... coal hydroliquefaction process."
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In point of fact, this Amoco Coal pretreatment technology, intended to make Coal easier to liquefy, and the resultant hydrocarbon liquids cleaner, with resultant process efficiencies, is merely an advancement on other Coal pre-liquefaction treatment technologies, some of which we have already reported for you; with other reports to follow.
The full Disclosure explains to a degree not only what "carboxylates" are; but, why one would want to "decarboxylate" Coal before one converted Coal into liquid hydrocarbons.
The thing to keep in mind, though, is:
Nearly two decades ago, our US knowledge base concerning the liquefaction of Coal, to synthesize liquid hydrocarbon fuels, was so broad and so advanced that the petroleum industry could focus on, and our United States Government could assess the validity of, such seemingly-esoteric matters as how to go about the "decarboxylation" of raw Coal "prior to liquefying" it.