Shawinigan process

The Shawinigan process uses a unique reactor system (36,37). The heart of the process is the fluohmic furnace, a fluidized bed of carbon heated to 1350—1650°C by passing an electric current between carbon electrodes immersed in the bed. Feed gas is ammonia and a hydrocarbon, preferably propane. High yield and high concentration of hydrogen cyanide in the off gas are achieved. This process is presently practiced in Spain, AustraUa, and South Africa. 

At Sasol the bulk of the CH, is either sold as fuel gas or is reformed to synthesis gas (se5 Figure 1). A portion is, however, sold as raw material for the production of NaCN and Ca(CN)2 which are used to extract gold from the milled ore. (Gold mining is a major industry in South Africa). In the Shawinigan process CH. and NH are passed through an electric arc and the HCN which is formed is absorbed by either NaOH or Ca(0H)2 solutions. 

The Shawinigan process (also called the Flouhmic process) was developed to use hydrocarbons (originally propane as well as methane) to produce hydrogen cyanide [18]. It is used mainly in regions where methane is not available. The reaction of propane and ammonia is [19]... 

This process takes place in an electrically-heated bed of coke particles at 1300—1600°C [20]. In order for the process to be economical, cheap and abundant power is required [21]. The advantages of the Shawinigan process are 1) hydrogen can be recycled to the ammonia feed unit, 2) there is no need for ammonia absorption facilities, and 3) the absence of water vapor and low concentration of ammonia suppresses undesirable polymerization [22], This process is currently used in a commercial plant in South Africa [23]. Other processes involved in the formation of hydrogen cyanide include ... 

The reaction produces temperatures exceeding 2,500°C at the carbon black surface. The carbon black formation takes place in the temperature region below 2,0(X)°C above 2,000°C a partial graphitization occurs. The Shawinigan process is a typical example of an acetylene process. ... 

In the Shawinigan Process, ammonia and natural gas are passed over coke. As practiced at BASF, formamide is heated and split into hydrogen cyanide and water ... 

Hoechst-Shawinigan A catalytic process for oxidizing acetaldehyde directly to acetic anhydride, using oxygen. See Shawinigan. 

Triolefin A process for disproportionating propylene into a mixture of ethylene and 2-butene. The reaction takes place at 160°C over a cobalt/molybdenum catalyst on an alumina base. Developed by the Phillips Petroleum Company from 1963. A commercial plant was built by Gulf Oil Canada in 1966 and operated by Shawinigan between 1966 and 1972 before closing for economic reasons. 

The process is nearing the end of a 3000 hour pilot trial at the Shawinigan laboratory of Hydro-Quebec in a commercial scale Electro Prod Cell, or an ICI FM21 SP cell, divided by a membrane. The pilot plant based on commercially available electrochemical cells has a design capacity of 100 t/year [132], Compounds examined on the laboratory scale using the Ce(IV) methane sulfonic acid process are summarized in Table 11. 

The individual graphitic layers are the basic building blocks of carbon black particles. The morphology and particle size distribution of carbon black is dependent on the source material and the process of its thermal decomposition. Particle size and distribution determine directly the specific surface area (SSA) which is one of the most important properties of carbon black for fuel cell applications. High surface area (ranging from a few hundreds to 2000-3000m2 g-1) carbon blacks suitable for fuel cell applications can be obtained from Cabot Corporation (Vulcan XC-72R, Black Pearls BP 2000), Ketjen Black International, Chevron (Shawinigan), Erachem and Denka. 

Shawinigan Chemicals of Canada developed the Fluohmic process around 1960. This process involves the reaction of ammonia with hydrocarbons... 

Fluohmic Process. The Fluohmic process was developed around 1960 by Shawinigan Chemicals of Canada. This process involves the reaction of ammonia with hydrocarbons (usually propane or butane) in an electrically heated, fluidized bed of coke. The reaction is ... 

In addition to plants already existing at Farbwerke Hoechst A. G. and Wacker Chemie G.m.b.H. in Germany, other plants have been or are being built by Rhone-Poulenc, France Societa Edison, Italy Pemex, Mexico Celanese Corp. at Bay City, Tex. and Shawinigan Chemicals Ltd., Canada. Plants are also being installed in Japan. Some use the one-stage, others the two-stage process for acetaldehyde manufacture, licensed by the Aldehyd G.m.b.H. 

The quality of the carbon black powder (Figure 6) product was evaluated as it impacts the overall economics of the process. A transmission electron photomicrograh (TEM) of a carbon black powder produced at a power level of 8.5 kW 2000 K) indicates a primary particle size of between 20 and 40 nanometers. In addition, the solar-thermally produced carbon black is compared to Shawinigan carbon black (tradename of Chevron-Phillips Corp.), the high quality world standard specialty carbon black. A comparative TEM image indicates that the carbon particles being formed have a similar chainlike structure as compared to the Shawinigan black. An X-ray diffraction pattern of the carbon... 

Commercialization of olefin metathesis was accomplished in 1966 (12), Shawinigan Chemical Ltd., at their Varennes complex near Montreal, Quebec, brought the Phillips Triolefin Process on stream. With an excess of propylene at that location,... 

Shawinigan had a need for polymerization-grade ethylene and high-purity butenes. This presented an ideal opportunity for application of the Triolefin Process, The commercial unit was operating at full capacity two weeks after start-up and its performance exceeded that predicted by laboratory and pilot plant studies. Part of the successful operation can be attributed to the very effective elimination of catalyst poisons from the commercial unit. In 1972, operation of the Shawinigan plant was terminated due to a change in economic climate. 

It was developed in order to valorize the C3 fraction of a local naphtha cracker. Shawinigan Chemicals Inc. Used this process in thewir plant near Montreal (at Varennes) in Canada from 1966 to 1972. The plant had a capacity of 50000 tons of feedstock per year. The catalyst used was tungsten oxide supported on silica and doped with sodium to prevent the double bond shift reaction of but-2-ene (which should decrease the selectivity). The operating temperature was between 370 and 450°C and the. conversion (40 - 43%) corresponded to near equilibrium conditions. The selectivity towards ethylene and but-2-ene was very high (> 95%). In addition, instead of pure propene, it was possible to use directly the C3 fraction (propane + propene) of the naphtha cracker. 

In the meantime Willson returned to Canada. He there established carbide operations in Merriton, Ontario, and at Shawinigan Falls, Quebec He formed the International Marine Signal Co. to manufacture carbide-energized buoys, and applied himself to the use of the electric furnace for smelting phosphate ores in his remaining years (W). Willson died in 1915, by which time he had seen his invention produce 90,000 tons of calcium carbide annually by 1904 and 250,000 by 1910, from zero in 1892 ( ). He perhaps would have been amazed to have witnessed the growth in the chemical uses of acetylene equivalent to one million tons per year of calcium carbide by 1960, produced in continuous furnaces which were 30 feet in diameter by 15 feet tall, each rated at 30,000 kw ( ). Nor could he have foreseen his furnace eventually supplanted as a source of acetylene by yet another electrothermic process, the direct formation of acetylene in an electric arc used to crack hydrocarbons such as natural gas. 

The first commercial olefin metathesis process, known as the Phillips Triolefin Process, was implemented by Phillips Petroleum Company just a few years after their initial report on the conversion of propylene to 2-butenes and ethylene. Hie process employed a heterogeneous W03/S102 catalyst at a temperature of approximately 400 ° C. The plant, operated by Shawinigan near Montreal, Quebec (Canada), opened in 1966 to convert excess propylene to butenes and polymer grade ethylene that were in short supply at the time. It operated at a capacity of 30 000 metric tons of butenes and 15000 metric tons of ethylene per year until the early 1970s, when an increased demand for propylene rendered the process tmeco-nomical. Produaion was halted in 1972. ... 

Fluohmic Process. This process was developed in the early 1960s by Shawinigan Chemicals. The reaction involves ... 

Shawinigan Acetylene Black has an extremely small particle size, which imparts excellent electrical and thermal conductivity, but is fluffy and care must be taken to obtain good dispersion. The specific gravity is 1.95 compared to 1.80 for furnace types of carbon black. Another more commonly used electrical conductive black is N472 (XCF), Vulcan XC72 from Cabot Corporation, which is easier to incorporate and process. 

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