Methanol synthesis BASF developments

It should be noted that on an industrial scale, reactions or other processes in SCF media are not new. Many industrial reactions developed in the early part of the twentieth century are actually conducted under supercritical conditions of either their product or reagent including ammonia synthesis (BASF, 1913), methanol synthesis (BASF, 1923) and ethylene polymerization (ICI, 1937). 

Future Methanol Processes. The process route for methanol synthesis has remained basically unchanged since its inception by BASF in 1923. The principal developments have been in catalyst formulation to increase productivity and selectivity, and in process plant integration to improve output and energy efficiency while decreasing capital cost. 

An industrial process to produce methanol from carbon monoxide and hydrogen was developed by BASF in 1923 using a zinc oxide-chromia catalyst.361 362 Since this catalyst exhibited relatively low specific activity, high temperature was required. The low equilibrium methanol concentration at this high temperature was compensated by using high pressures. This so-called high-pressure process was operated typically at 200 atm and 350°C. The development of the process and early results on methanol synthesis were reviewed by Natta 363... 

Tlte synthesis of liquid hydrocarbons was first reported in patents from BASF in 1913. Alkali activated Co/Os catalysts were used at pressures over 100 bar and temperatures exceeding 300 C. The products obtained consisted of paraffins, olefins, and oxygenated products (I ). Tlte continuation of these studies led to the development of the methanol synthesis. The first commercial plant went on stream in 1923. 

In this problem, we will determine the degrees of freedom of a process circuit conqjosed of several process units by examining a methanol-synthesis process. Methanol was first synthesized from carbon monoxide and hydrogen on a commercial scale in 1923 by Badische Anilindund Soda-Fabrik (BASF) in Germany [25]. Methanol is an important basic bulk chemical used in the synthesis of formaldehyde and acetic acid [28] and it has been proposed as an automobile fuel and fixel additive [26]. Methanol has also been proposed as a substrate to produce a bacterium suitable as a protein source (single-cell protein). The bacterium would be a soy meal and fishmeal substitute for animal and poultry feeds [27]. If these applications should ever develop, the demand for methanol will increase considerably. 

Matthias Pier (1882-1965), a German chemist, worked with Emil Fischer and Walter Nernst during his studies. After WWI, he joined BASF and worked on ammonia and methanol synthesis. After BASF had purchased the patent on coal liquefaction from Bergius in 1925, he developed this process further. He found better and sulfur-resistant catalysts and increased the yield of fuels by arranging the process in two steps, liquid-phase hydrogenation and gas-phase hydrotreating of the intermediate product. Thus, the process is therefore mostly known as the Bergius-Pier process. 

In 1920s, the studies on the catalysts for ammonia sjmthesis were performed sporadically in BASF, instead, the company mainly focused on the organic synthesis under high pressm-es and the new fields in heterogeneous catalysis. Dm-ing the development of ammonia synthesis catalysts, researchers provided valuable information about the dm-ability, thermal stability, sensitivity to poisons, and in particular to the concept of promoter. Mittasch smnmarized the roles of various additives as shown in Fig. 1.9. The hypothesis of successful catalyst is multi-component system proposed by Mittasch was confirmed to be very successful. Iron-chromium catalysts for water gas shift reaction, zinc hromium catalystfor methanol synthesis, bismuth iron catalysts for ammonia oxidation and iron/zinc/alkali catalysts for coal hydrogenation were successively developed in BASF laboratories. 

In the United States, a subsidiary of the DuPont Company, Lazote, Inc., made synthetic methanol at Belle, West Virginia. The Belle operation was part of the ammonia plant at the site. The methanol production was actually a step in the ammonia process for removing carbon monoxide, which was an impurity in the ammonia synthesis gas. Commercial Solvents was the first to employ the high-pressure synthesis process, developed by BASF, in the United States. The plant, located in Peoria, lUinois, began operation a few months after the Lazote plant at Belle. The Commercial Solvents plant used an off-gas from a fermentation operation. The off-gas contained carbon dioxide and hydrogen from the production of butanol from corn. This first of a kind plant in the United States was rated at about 4000 t per year. 

Subsequently, patents covering the conversion of synthesis gas to complex mixtures of organic oxygen compoimds, including methanol, were issued to BASF during 1913. This followed work by Mittasch and Schneider. Full-scale production of methanol was not attempted, however, imtil 1923. By that time high-pressure equipment had been in operation for several years in the new ammonia process. The methanol process was developed by Piers and the plant, built at Leima, used mixed zinc oxide-chromic oxide catalyst. The use of metallic iron for the internal parts of the reactor was avoided to prevent the formation of the volatile iron penlacarbonyl. The would have decomposed on the surface of the catalyst, to deposit finely divided iron metal, which in turn would have promoted the exothermic formation of methane. 

The hydroquinone process was developed by BASF [12]. Hydroquinone-2,5-di-carboxylic acid is prepared by a modified Kolbe-Schmidt synthesis from hydroquinone and carbon dioxide. Subsequent reaction with arylamine in an aqueous-methanolic suspension in the presence of an aqueous sodium chlorate solution and a vanadium salt affords the product in good yield ... 

The first commercial plant that converted synthesis gas to methanol was built in 1924 in Germany by BASF. It ran at very high pressures (3500—5000 psi) and used a zinc-copper catalyst. In the years since then, further development of catalysts has brought the pressures down, eliminating much of... 

BASF led the development of a route based on ethylene and synthesis gas. Its four step process begins with the production of propionaldehyde from ethylene, CO, and H2 using a proprietary catalyst mixture that they aren t telling anything about. Reaction with formaldehyde gives methacrolein. The last two steps are the same as above—oxidation with air yields the MAA subsequent reaction with methanol yields MMA. 

Methanol was first produced commercially in 1830 by the pyrolysis of wood to produce wood alcohol. Almost a century later, a process was developed in Germany by BASF to produce synthetic methanol from coal synthesis gas. The first synthetic methanol plant was introduced by BASF in 1923 and in the United States by DuPont in 1927. In the late 1940s, natural gas replaced coal synthesis gas as the primary feedstock for methanol production. In 1966, ICI announced the development of a copper-based catalyst for use in the low-pressure synthesis of methanol. 

As mentioned in the previous section, the carbonylation of methanol to acetic acid is an important industrial process. Whereas the [Co2(CO)s]-catalyzed, iodide-promoted reaction developed by BASF requires pressures of the order of 50 MPa, the Monsanto rhodium-catalyzed synthesis, which is also iodide promoted and which was discovered by Roth and co-workers, can be operated even at normal pressure, though somewhat higher pressures are used in the production units.4,1-413 The rhodium-catalyzed process gives a methanol conversion to acetic acid of 99%, against 90% for the cobalt reaction. The mechanism of the Monsanto process has been studied by Forster.414 The anionic complex m-[RhI2(CO)2]- (95) initiates the catalytic cycle, which is shown in Scheme 26. 

Two key intermediates in the production of vitamin A are citral and the so-called C5 aldehyde. In the modem routes to these intermediates, developed by BASF and Hoffmann-La Roche, catalytic technologies are used (see Fig. 2.29 and 2.30). Thus, in the synthesis of citral, the key intermediate is 2-methyl-l-butene-4-ol, formed by acid-catalyzed condensation of isobutene with formaldehyde. Air oxidation of this alcohol over a silver catalyst at 500°C (the same catalyst as is used for the oxidation of methanol to formaldehyde) affords the corresponding aldehyde. Isomerization of 2-methyl-l-butene-4-ol over a palladium-on-charcoal catalyst affords 2-methyl-2-butene-4-ol. The latter is then reacted with the aldehyde from the oxidation step to form an enol ether. Thermal Claisen rearrangement of the enol ether gives citral (see Fig. 2.29). 

Also at Palm Springs, two papers by the Methanol Fuel Cell Alliance (Ballard/BASF/BPAmoco/Daimler Chrysler/Methanex/Statoil) and the Methanol Institute, respectively, portray the existing substantial methanol production, distribution and trading based on natural gas reform/synthesis gas/methanol, as in the Methanex Canada plant. Methanol from biomass is a future possibility. A methanol pump can be fitted within the footprint of many existing diesel/gasoline filling stations, and an Identic refuelling nozzle has been developed in Sweden, to avoid confusion between methanol and alternative fuels. 

The low-pressure acetic acid process was developed by Monsanto in the late 1960s and proved successful with commercialization of a plant producing 140 X 10 metric tons per year in 1970 at the Texas City (TX, USA) site [21]. The development of this technology occurred after the commercial implementation by BASF of the cobalt-catalyzed high-pressure methanol carbonylation process [22]. Both carbonylation processes were developed to utilize carbon monoxide and methanol as alternative raw materials, derived from synthesis gas, to compete with the ethylene-based acetaldehyde oxidation and saturated hydrocarbon oxidation processes (cf. Sections 2.4.1 and 2.8.1.1). Once the Monsanto process was commercialized, the cobalt-catalyzed process became noncom-... 

In 1975, Chem Systems developed the liquid phase methanol (LPMeOH) process which is based on the low pressure synthesis technology except that the new process is carried out in an inert oil phase [79], The catalytic system used is Cu/Zn0/Al203, that is modified for slurry operation (i.e., attrition resistant, finely powdered, and leaching resistant). The S3.85 and S3.86 catalysts of BASF and EPJ-19 and EPJ-25 catalysts of United Catalysts Inc. were developed for this process [14,19]. The process has been tested for commercial feasibility at a demonstration scale by Air Products and Chemicals, Inc [79]. 

Pure cyclohexanol can also be obtained by the hydrogenation of phenol with a palladium catalyst at 150°C and 10 atm although e process is not widely used. Attempts were made by BASF to synthesize adipic acid from butadiene via a two-step caibonylation process in the presence of methanol. The first step of the synthesis operated at 130°C and 600 bar while the second operated at 170°C and a lower pressure of 160 bar. A typical cobalt catalyst with organic ligands was used, but the process was never developed industrially. 

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