United States Patent: 4172814
We've previously cited a number of Carbon conversion technologies that had been developed by Michigan's rather well-known Dow Chemical Company.
We made report of one Dow technology pertaining specifically to Coal liquefaction in:
DOW Chemical Liquefies Coal in 1978 | Research & Development; concerning: "United States Patent 4,102,775 - Conversion Process for Solid Hydrocarbonaceous Materials; 1978; Inventors: George Quarderer and Norman Moll; The Dow Chemical Company, Midland, MI; Abstract: Solid, hydrocarbonaceous materials, such as coal, are converted to valuable liquid and gaseous products by an efficient process comprising: (1) preparing a slurry from slurry oil, a hydrogenation catalyst and the hydrocarbonaceous material; (2) hydrogenating the hydrocarbonaceous material to liquid and gaseous hydrogenation products".
And, we documented how that same team of Dow scientists developed additional technology for the further refining of hydrocarbon liquids derived from Coal, in:
DOW Chemcial Refines Coal Liquids | Research & Development; concerning: "United States Patent 4,180,456 - Process for Recovering Premium Oil from .. a Solid, Hydrocarbonaceous Fuel; 1979; Inventors: Norman Moll and George Quarderer; The Dow Chemical Company; Abstract: A feed slurry containing fine solids, polar liquids and premium liquid oil and produced by high temperature hydrogenation of a solid fuel, such as coal ... . An improved process for separating a feed slurry produced by high temperature hydrogenation of a solid hydrocarbonaceous fuel and comprising fine solids, polar liquids and premium liquid oil ... wherein said feed slurry is produced from coal."
The above Dow Chemical technologies, as we see them, are direct Coal hydrogenation and liquefaction processes that require the Coal to be exposed, at elevated temperature and pressure, to an atmosphere of elemental, molecular Hydrogen.
In that way, they are conceptually related to the Nobel Prize-winning Coal liquefaction process developed in Europe, early in the last century, by Germany's Friedrich Bergius, about which we again lately reported in:
More Nobel Prize-Winning Coal Liquefaction | Research & Development; concerning: "United States Patent 1,391,664 - Hydrogenating Carbon Compounds Under High Pressure; 1921; Inventor: Friedrich Bergius;
Abstract: This invention is an improvement in the process of hydrogenating, under high pressure and at an elevated temperature, natural coal or other products of carbonization of wood and other vegetable matter (which) are carbonized by the heat of the process. By such process, these carbonaceous materials are transformed into liquids".
The difference seems to lie in the fact that Dow, in their Coal hydrogenation and liquefaction technologies, employ an "oil", generated by the process itself, to "slurry", or suspend, Coal particles; and, it is that blend of Coal and Coal oil that is exposed to pressurized Hydrogen; with the Coal oil serving to facilitate the transfer of gaseous Hydrogen into chemical reactions with the raw Coal; with the Coal being thus hydrogenated and liquefied, forming both the desired liquid hydrocarbon products and more of the liquid oil Hydrogen transfer agent.
In that way, the high pressures and temperatures required by the original, 1921, Bergius Coal hydrogenation process can be greatly reduced.
And, that reduction in required pressures and temperatures, with subsequent reduction in the overall cost of converting Coal into hydrocarbon liquids, can be further enhanced through the use of readily-available and inexpensive metal catalysts.
As Dow Chemical further explains, in excerpts from the initial link in this dispatch to:
"United States Patent 4,172,814 - Emulsion Catalyst for Hydrogenation Processes
Date: October, 1979
Inventors: Norman Moll and George Quarderer, MI
Assignee: The Dow Chemical Company, MI
Abstract: In the catalytic hydrogenation of a substance in a water-immiscible organic liquid medium, a metallic hydrogenation catalyst is conveniently and effectively dispersed in the reaction mixture by addition as an emulsion of an aqueous solution of a salt of the metal in the liquid medium.
The method is particularly applicable to the liquefaction of coal.
(Note the statement from the Abstract immediately above. That is what this invention is all about. But, certain wording and turns of phrase in the full Disclosure tend to obfuscate that fact. We are selecting our excerpts so that the intent and purpose are perfectly clear.)
Claims: (The) process for hydrogenating a hydrogenatable organic substrate ... by contacting said substrate as a water-immiscible liquid phase with hydrogen in the presence of a metal-containing hydrogenation catalyst, the improvement wherein said metal-containing catalyst is initially added to the water-immiscible liquid phase as an emulsion of a water solution of a compound of said metal in said liquid phase, said compound being convertible to the hydrogenation catalyst under the conditions of hydrogenation.
The process ... wherein a hydrocarbonaceous substance is hydrogenated to lower boiling products by contacting a dispersion of said substance in a liquid hydrocarbon medium with hydrogen at elevated temperature and pressure.
(Note, for clarity: The "hydrocarbonaceous substance" can be Coal, and, the "liquid hydrocarbon medium" in which the "substance" is dispersed can be a Coal oil generated in the process itself.)
The process ... wherein the hydrogenation temperature is about 400 (to) 500C.
The process ... wherein the metal is molybdenum.
(Concerning the "molybdenum", world prices for it have fluctuated between $30 and $50 per pound for the past several years, and experts, according to a number of sources we checked, expect it to stay in that range. So, even though it ain't platinum, it is kind of pricey. On the upside, it is a catalyst in this process, it doesn't leave the process to any appreciable extent, and, any that gets converted into un-reactive compounds can be re-refined with relative ease.
Further, as can be learned from the US Geologic Survey, in:
http://minerals.usgs.gov/
we, in the US, have, behind China, far and away the second-largest natural reserves of it in the world. We can produce plenty of it domestically; and, even though we do, for whatever reason, import some, we actually export more than we import.)
The process ... wherein 0.01-1 percent of molybdenum is present in the slurry based on the weight of substrate.
(So, if you think about it, if we go about hydrogenating Coal in a big way with this process, we would need an appreciable amount of Molybdenum. But, again, it isn't "used up" by the process, and, we have plenty.)
The process ... wherein the metal is a mixture of cobalt and molybdenum (or) nickel and molybdenum.
The process ... wherein the metal is iron.
The process ... wherein the metal is tungsten.
(If we run short on Cobalt or Nickel, we can turn to our good friends in Canada and Australia, who have plenty. Canada has plenty of Tungsten, as well. We do have some domestic US Tungsten deposits, but, not, as far as we were able to determine, any current domestic US production.)
Description and Background: The present invention relates to an improved method whereby a hydrogenation catalyst is conveniently and effectively dispersed in and contacted with a reaction mixture. It relates particularly to an improved method for dispersing such catalysts in ... liquid hydrocarbon slurries of coal prior to hydrogenation.
The hydrogenation of finely divided coal ... to mixtures of gaseous and liquid products has been studied for many years. In recent years, the liquefaction of coal in particular has become of more urgent interest because of dwindling petroleum resources. Although coal can be successfully hydrogenated to produce both gaseous and liquid products without the addition of a hydrogenation catalyst, since traces of catalytically active metals are normally present in coal, better yields of the desired products are obtained under more moderate reaction conditions when a metal hydrogenation catalyst is used.
Active catalysts for these processes constitute a known class including the metals or compounds of the metals iron, nickel, cobalt, molybdenum, tungsten, tin, zinc, vanadium, chromium, antimony, and a number of others, alone or in combination. Active metals such as palladium, platinum, and rhenium are also effective but are too expensive for the purpose. These hydrogenation catalysts can be added to the hydrogenation mixture as the finely divided metals or as compounds thereof, either supported or unsupported. In the hydrogenation of coal ... the predominant stable form for most of these metal catalysts is the sulfide which can be formed during the hydrogenation process from the sulfur naturally present in these fossil hydrocarbonaceous substances ... .
(Thus, having a little Sulfur in our Coal to start with is a good thing.)
Two well researched processes use a bed of particulate catalyst, usually a nickel or cobalt molybdate supported on alumina, through which are pumped a mixture of hydrogen and a dispersion of finely divided coal in a liquid hydrocarbon medium or a heavy hydrocarbon fraction at elevated temperature and pressure.
The Synthoil process, developed at the U.S. Bureau of Mines for the hydrogenation of coal, employs a stationary bed of pelleted or granular catalyst.
(Concerning that Bureau of Mines, USBM, technology, see, for one example:
Pittsburgh USBM 1949 Coal Liquefaction | Research & Development; concerning: "United States Patent 2,476,999 - Solvation and Depolymerization of Coal; 1949; Inventor: Milton Orchin, Pittsburgh, PA; Assignee: The United States of America; Abstract: This invention relates to the conversion of ... bituminous and subbituminous coals ... to liquid products of enhanced values and utility. It is an object of my invention to secure the solution of solid carbonizable fuels under the mildest conditions possible (and) the improvement of hydrogenation of coal ... using for the vehicle ... liquid fractions produced from such extracts.")
The "ebullated bed" or H-Coal process employs a bed of similar but more finely divided catalyst which is maintained in the reactor in a turbulent or boiling state as the reaction mixture is passed through it, thereby maximizing contact with the catalyst particles.
(See, for one example:
More on Kentucky's H-Coal CTL Process | Research & Development; concerning: "The H-Coal Process;
Publication: University of Pittsburgh, Annual International Conference on Coal Gasification and Liquefaction, 3rd, Pittsburgh, Pa., Aug. 3-5, 1976, Paper. 14 p. Research supported by the Electric Power Research Institute, Ashland Oil, Inc., Commonwealth of Kentucky, and ERDA; Abstract: The H-Coal Process pilot plant, located at Catlettsburg, Kentucky, is designed for two modes of operation: (1) to process 600 tons of coal per day to produce 1,820 barrels of fuel oil containing no more than 0.7 wt % sulfur from coal containing more than 3 wt % sulfur (fuel oil mode), and (2) to process 200 tons of coal per day to produce 705 barrels per day of synthetic crude (syncrude mode).")
Summary: It has now been found that in the process for hydrogenating a hydrogenatable organic substrate by contacting that substrate as a water-immiscible liquid phase with hydrogen in the presence of a metal-containing hydrogenation catalyst, the catalyst is conveniently introduced into and efficiently dispersed in the liquid phase by initially adding it as an emulsion of a water solution of a compound of the metal in the said liquid phase, the metal compound being convertible to the active hydrogenation catalyst under the conditions of hydrogenation. The active catalyst is thereby formed in situ as microscopically fine particles uniformly dispersed in the liquid reaction mixture.
The method of catalyst addition and dispersion is particularly applicable in the hydrogenation of a dispersion of coal in a liquid hydrocarbon medium ... . Under the conditions of this hydrogenation process, there is no longer a separate aqueous phase and the dissolved metal compound is decomposed and converted to an active form of the metal catalyst, probably a sulfide.
Thus the invention is essentially an improved method whereby a catalyst is more conveniently and efficiently dispersed and utilized so that a very small quantity can provide optimum results.
This new method is of special interest in the liquefaction of coal, more particularly, coal crushed and dispersed in a liquid hydrocarbon medium to provide a pumpable slurry."
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We'll leave it there.
Again, our take on it is, that, through the use of a "pumpable slurry" of Coal particles in Coal-derived oil, and, of a "conveniently and efficiently dispersed", relatively inexpensive and available, metal catalyst, a catalyst that needs to be present in only "a very small quantity", we can, much more efficiently, at lower pressures and lower temperatures, effect the direct hydrogenation and transformation of Coal into "lower boiling" hydrocarbon liquid "products".
Free, molecular Hydrogen is required for the process; and, we remind you that, as seen, for one example, in:
USDOE Makes Hydrogen by Using Sulfur Dioxide | Research & Development; concerning: "United States Patent 4,244,794 - Hydrogen Production by the Decomposition of Water; 1981; The United States of America; This invention relates generally to the production of hydrogen gas from water and in particular relates to a sulfuric acid process for producing hydrogen. Claims: A process for producing hydrogen comprising: passing an electric current from a cathode to an anode through water containing sulfur dioxide so as to produce hydrogen gas at the cathode and so as to oxidize the sulfur dioxide to form sulfuric acid at the anode, thus producing an aqueous solution of sulfuric acid";
we can make that Hydrogen, in an energy-efficient process that also generates commercially-valuable byproduct Sulfuric Acid, by utilizing what could be the effluent from a system that uses water to scrub Sulfur Dioxide from the exhaust stream of some industrial process that happens to generate a little byproduct Sulfur Dioxide in the course of it's primary business.
Finally, in closing, we'll remind you that, should you be surprised that an industrial chemical enterprise like Dow is interested enough to actively be developing Coal conversion technologies, it seems clear that Dow recognized the vast potentials for Coal long ago; and, that might be why, in 2001, subsequent to their own development of the several Coal conversion technologies we cite and make report of herein, as can be learned via:
Union Carbide - Wikipedia, the free encyclopedia; Dow acquired the old Union Carbide Company, making of them a wholly-owned subsidiary.
And, with that acquisition of Union Carbide, Dow also acquired all of the Coal conversion technologies that Union Carbide had earlier developed, in the state capital of West Virginia, as seen, for just one example, in:
Charleston, WV, Coal + Steam = Hydrocarbon Syngas | Research & Development; concerning: "United States Patent 3,988,237 - Integrated Coal Hydrocarbonization and Gasification of Char; 1976; Inventors: Hubert Davis, Charles Albright, et. al.; all of West Virginia; Assignee: Union Carbide Corporation; Abstract: An integrated continuous process for the production of liquid and gaseous fuels (from) coal".
The Dow Chemical Company, in Michigan, obviously, knows about the true value and potentials of Coal.
Far past time all the common folk in West Virginia, and the rest of United States Coal Country, were given the opportunity to acquire that same sort of knowledge.