Patent Number: 044341334
Section: summary

BACKGROUND OF THE INVENTION Coal can be efficiently converted into hydrocarbons of a more useful gaseous or liquid form by coal gasification or liquefaction techniques, utilizing energy from a high-temperature, gas-cooled nuclear reactor for the endothermic and/or electrolytic processing required, as taught by Jones, in U.S. Pat. No. 4,158,673. While the United States, the Soviet Union, and China still contain major deposits of coal, this mineral is considered precious in most other parts of the world, where deposits are either lacking or have been largely used up. Thus, while the earth's supply of precious fossil fuels is being steadily depleted to provide electricity and petrochemicals, a virtually unlimited worldwide supply of other carbon bearing minerals remains untapped as an energy source. Salotti, in U.S. Pat. No. 3,558,724, taught that inorganic crystalline carbonates could provide gaseous products containing up to 4% methane, if the carbonates were first heated in an oxygen-free atmosphere at from about 400.degree. C. to 700.degree. C., and then contacted with excess hydrogen gas at from about 200 psi. to 10,000 psi. This process, however, uses large quantities of valuable hydrogen gas, which is becoming increasingly important itself as an energy source. In addition, this process provides a poor yield of methane, leaves carbon residue and maintains explosive reaction conditions. Tamers, in U.S. Pat. No. 4,009,219, taught the production of benzene from inorganic carbonates such as limestone. Tamers reacted limestone (CaCO.sub.3) with lithium metal in a vacuum at 500.degree. C., raised the temperature of reaction to 1,000.degree. C. for 30 minutes to reverse secondary reactions that produce carbon and metal oxide, and then hydrolyzed the resulting product lithium carbide (Li.sub.2 C.sub.2) with water. This produced acetylene, with calcium oxide and lithium hydroxide by-products. The lithium hydroxide was converted to lithium metal by fused salt electrolysis, and recycled back to the limestone reaction. The acetylene was then purified and dried. Benzene was produced from this treated acetylene, using dried potassium chromate activated silica-alumina catalyst at 120.degree. C. to 200.degree. C. Benzene, however, is now known to be toxic and a carcinogenic agent. What is needed is a method to produce high carbon chain hydrocarbons without using valuable fuels such as coal or hydrogen or producing toxic substances such as benzene. SUMMARY OF THE INVENTION It has been discovered that the above-described need can be met by a process comprising the steps of: (1) reacting inorganic, crystalline or non-crystalline, carbon containing mineral material, such as CaCO.sub.3, with a stoichiometric excess of molten lithium metal, in a lithium reactor means, in an inert atmosphere, at a temperature of between about 300.degree. C. and about 1,200.degree. C., to provide lithium salt compounds such as Li.sub.2 C.sub.2 and Li.sub.2 O, and formation of CaO; (2) hydrolyzing the Li.sub.2 C.sub.2 to provide C.sub.2 H.sub.2 (acetylene gas). A lithium hydroxide slurry formed from the Li.sub.2 O can be recovered from the hydrolysis step and converted to lithium metal by a variety of means, such as fused salt electrolysis, for recycle to the lithium reactor means; (3) reacting the C.sub.2 H.sub.2 with steam at between about 250.degree. C. and about 475.degree. C. in the presence of catalysts such as ZnO, to provide CH.sub.3 COCH.sub.3 (acetone). The C.sub.2 H.sub.2 does not have to be purified for this reaction to occur; (4) pyrolyzing the CH.sub.3 COCH.sub.3 at between about 600.degree. C. and about 800.degree. C., to provide ketene gas, which is then cooled to -60.degree. C. by a suitable cooling means, to provide a ketene product (CH.sub.2 .dbd.C.dbd.O) in liquid form, and separable methane gas. The ketene can then be stored as a liquid at 25.degree. C. under a pressure of about 40 psi, if desired. In reduction step (1) and hydrolysis step (2), a total of approximately 976 kJ. of energy is gained for each mole of CaCO.sub.3 used. Some of this energy can be used to keep the lithium reactor at temperature. The CaO still present in step (2) can be separated from the lithium hydroxide slurry for use in other industries, such as an alkali for water treatment, etc. By-product hydrogen from step (3) and methane from step (4) can be separated and used as fuels. The electrolysis step to provide lithium metal, and the pyrolysis step to provide ketene require a large expenditure of energy, which could be supplied by a pressurized water nuclear reactor, or a high-temperature, gas-cooled nuclear reactor, without major modifications in design or structure of the reactor. Energy from the nuclear reactor could also be used to help keep the lithium reactor at temperature, and to provide steam and heat to produce acetone from acetylene. Thus, uranium would be the chief fuel consumed in the process of converting the inorganic carbon into an organic carbon, which can be used to produce liquid hydrocarbon fuels such as diesel oil or gasoline. The ketene can be photochemically decomposed or thermally decomposed to produce extremely reactive, organic methylene. A particular type of insertion chain reaction sequence could then be started between methylene and alkanes, such as methane, which could be easily supplied as a by-product from the pyrolysis reaction. This could ultimately result in a mixture of ethane, propane, butane, pentane, hexane, heptane, and possibly higher carbon chain hydrocarbons such as octane. The pyrolysis of acetone, the decomposition of ketene and the methylene insertion chain reaction to form ethane and higher hydrocarbons, can be accomplished as separate steps, or they can be combined in various fashions. Thus, by the method of this invention, limestone type minerals can be reacted to form gasoline-type molecules via a ketene reaction sequence, utilizing energy from an already existing nuclear power source.