Published October 1968
Methanol was evaluated in PEP Report No. 43 in October 1968 and in PEP Report No. 43-A1 in July 1972. Since then, significant changes have taken place in the methanol industry. Lower pressure, copper catalyst processes., which were just becoming established, have now almost entirely replaced the older, high pressure zinc-chromium oxides route to methanol. The last existing high pressure plants in the United States will be converted to low pressure in 1981. Natural gas, which is the principal raw material for methanol produced in the United States, has undergone a tenfold increase in price since the early 1970s. This has resulted in low pressure process design changes to increase the efficiency of natural gas usage--generally, at additional capital investment. A third, and potentially the most far-reaching change, is the growing attention to nonhydrocarbon sources for chemicals and energy. Methanol produced from coal can be used directly as a fuel, in mixtures with hydrocarbons, or it can be converted to methyl tertiary butyl ether--a gasoline additive-- or dehydrated to gasoline by the, still developing Mobil process. The successful commercialization of any of these fuel alternatives could initiate a large scale expansion of methanol output.
Section 5 of this report evaluates the two most widely used low pressure methanol processes--ICI and Lurgi. Section 6 examines current commercial Koppers-Totzek technology for large scale methanol production from subbituminous coal. The potential improvement in the economics of methanol from coal by two other processes--Shell-Koppers and Texaco partial oxidation--is also estimated.
Copper-catalyzed methanol processes have sometimes been divided into low pressure, 50 to 75 atm, and intermediate pressure, 75 to 150 atm. This study considers all copper-catalyzed methanol systems to be low pressure and distinct from those using zinc-chromium oxides catalysts at 250 to 450 atm. The word "methanol" in this study refers to synthetic methanol exclusive of natural methanol or wood alcohol. Methanol for fuel applications--unlike that for chemical and electronic uses--has no standard purity specifications (see Appendix C).
