Technology for dehydrogenation of propane to make highpurity propylene. The CATOFIN process uses specially formulated proprietary catalyst from Süd-Chemie.
Description: The CATOFIN reaction system consists of parallel fixed-bed reactors and a regeneration air system. The reactors are cycled through a sequence consisting of reaction, regeneration and evacuation/purge steps. Multiple reactors are used so that the reactor feed/product system and regeneration air system operate in a continuous manner.
Fresh propane feed is combined with recycle feed from the bottom of the product splitter (6). The total propane feed is then vaporized and raised to reaction temperature in a charge heater (1) and fed to the reactors (2). Reaction takes place at vacuum conditions to maximize feed conversion and olefin selectivity. A purge stream, taken from the total propane feed, is passed through a deoiler (8) to remove C4 and heavier components.
After cooling, the reactor effluent gas is compressed (3) and sent to the recovery section (4), where inert gases, hydrogen, and light hydrocarbons are separated from the compressed reactor effluent. The ethane, propane and propylene components are then sent to the product purification section deethanizer (5) and product splitter (6), where propylene product is separated from unreacted propane. The propane is recycled to the reactors.
After a suitable period of onstream operation, feed to an individual reactor is discontinued and the reactor is reheated/regenerated. Reheat/regeneration air heated in the regeneration air heater (7) is passed through the reactors. The regeneration air serves to restore the temperature profile of the bed to its initial onstream condition in addition to burning coke off the catalyst. When reheat/regeneration is completed, the reactor is re-evacuated for the next onstream period. The low operating pressure and temperature of the CATOFIN reactors, along with the robust Süd-Chemie catalyst, allows the CATOFIN technology to process propane feedstock from a variety of sources. The simple reactor construction, with its simple internals, results in a very high onstream factor.
Yields and product quality: Propylene produced by the CATOFIN process is typically used for the production of polypropylene, where purity demands are the most stringent (>99.5%). The consumption of propane (100%) is 1.17 metric ton (mt) per mt of propylene product.
Licensor: Lummus Technology
