Suspensoid process

Only one once-through process (Fig. 21-ld), the Suspensoid process, has been applied commercially. The catalyst (spent lubricating-oil clay) passes through the cracking furnace along with the oil and is removed from the fuel oil by an Oliver precoat filter. ... 

Suspensoid An early catalytic cracking process in which the silica-alumina catalyst was suspended in the petroleum. First operated in Ontario in 1940. 

Suspensoid catalytic cracking a nonregenerative cracking process in which cracking stock is mixed with slurry of catalyst (usually clay) and cycle oil and passed through the coils of a heater. 

In 1934, R. K. Stratford at Jersey s Canadian affiliate (Imperial Oil Co.) discovered that the spent clay used in lube oil treating had catalytic effects. Four thermal crackers were eventually revamped to "Suspensoid Cracking" by adding 2 to 10 pounds of powder/barrel feed in 1940. This catalyst was used in a once through mode and improved the yield selectivities from the thermal cracking process (16). 

Superficially, the free radical polymerization of TFE to form PTFE seems to be a relatively simple process. One starts with an autoclave partly full of water containing a very small amount of an initiator and, perhaps, some surface active agent. The mixture is heated at a moderate temperature, very pure TPE monomer is introduced into the kettle under pressure, and the polymer forms as white, relatively coarse particles in granular polymerization and as a milky-looking suspensoid in the other type. When the desired amount of polymer is obtained, the batch is cooled and the polymer is isolated. All of these operations must be done by remote control of the well-barricaded autoclaves. 

There is a common misconception that these products are made by an emulsion polymerization. They are not, even though the product is often called a "latex", emulsion, dispersion, etc. For a classic emulsion polymerization to occur one must have liquid monaqueous phase. During the polymerization of TFE, as it is done in many ccmimercial processes, the temperature is well above the critical temperature of TFE and the pressure is well below the critical pressure of the monomer. There are many different ideas as to the exact mechanism of the polymerization, but this writer at least, is not aware of any results that show convincingly exactly what happens. The dispersion is really a suspensoid, with particles varying in shape, but with dimensions of the order of 0.2-0.4 micr[Pg.271]

Once-through the Suspensoid catalytic cracking process once attracted attention. ... 

Octane number is probably affected more by the reaction temperature than by any other variable. The trend of octane number is indicated in Table 21-5 for a fixed percentage conversion. Similar data are. given for the Fluid process alone by Murphree and associates, f and for the T.C.C. process alone by Noll and associates. Table 21-5 does not apply directly to Cycloversion, Suspensoid, or Hydroforming operations, but the general trend is the same. 

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