Olefins Conversion Technology OCT

OCT was originally developed by Phillips Petroleum and was first commercialized in 1965 when it was used to produce ethylene and butenes from propylene, due to the over-supply of the latter at that time. With the 

The ethylene feed can be polymer grade or lower purity as long as the impurities are below a certain limit. Any saturated hydrocarbons, such as ethane and methane, do not react. A variety of C4 streams, including mixed C4 s produced by FCC or steam cracking, or C4 Raffinate from butadiene extraction or MTBE production, can be used in the process. In order to achieve the full potential propylene production. However, the raw C4 cut requires pretreatment to maximize its butene-2 content. 

A simplified flow process for Lummus OCT can be described as follows. Fresh and recycled C4 s are mixed with ethylene and recycled ethylene feeds and sent through a guard bed which removes trace impurities from the mixed feed. The feed is heated prior to entering the vapor phase fixed-bed metathesis reactor where the equilibriiun reaction takes place. The catalyst is regenerated in situ on a regidar basis. The per-pass conversion of butene is greater than 60 wt% with overall selectivity to propylene exceeding 90 wt%. The product from the metathesis reactor contains mainly propylene and umeacted feed. 

A standalone OCT imit requires a polymer grade ethylene feed and specific invest. When integrated with an ethylene plant, however, OCT provides the flexibility to economize on feedstock while varying the ratios of light olefins produced. The typical propylene to ethylene ratio of 0.4 to 0.6 in an ethylene plant can be extended to greater than 1. OCT can also be combined with FCC in order to reduce the investment cost per ton of propylene produced. 

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As mentioned above, the first metathesis reaction studied was the equilibrium between propylene and an ethylene 2-butene mixture. In the initial Phillips process this was used to convert excess propylene into ethylene and 2-butene (Scheme 5.55). When propylene demands surged, the process was reversed and is now known as olefins conversion technology (OCT). The OCT process is operated with a fixed-bed reactor, W03 on silica serves as a catalyst. In order to allow... 

Application To produce propylene from ethylene and butenes using Lummus olefin conversion technology (OCT). Other OCT process configurations involve interconversion of light olefins and production of C2— C5 mono-olefins. 

Olefin metathesis (Olefin Conversion Technology, OCT) of ethylene and 2-butene (manufaaured by isomerization of 1 -butene) yielding propylene. ... 

Because olefin metathesis is an equilibrium reaction, the Triolefin Process can be mn in the reverse direction to produce propylene from 2-butene and ethylene. Lyondell licensed the Phillips Triolefin process and opened the first propylene plant based on this technology in 1984, eventually expanding capacity to 450 000 metric tons per year. In 1997, Lummus Technology, who engineered the first two applications under license from Phillips, purchased the technology from Phillips. The metathesis of ethylene and butenes to propylene is now commercialized as Olefins Conversion Technology (OCT )... 

Olefins Conversion Technology [OCT] A process for converting mixtures of ethylene and butenes to propylene by metathesis (disproportionation). Based on technology developed by Phillips Petroleum in the... 

The Phillips triolefin process [56] developed at Phillips Petroleum, used a heterogeneous WOj/SiOj catalyst in metathesis reaction to convert propene 127 into mixture of ethene 125 and 2-butene 126. As it is a reversible reaetion (Scheme 9.32) and the price of propene rose high, the reverse reaction of Philips process offered is now by using Lummus teehnology to produce propene known as Olefin Conversion Technology (OCT). 

OCT [Olefins conversion technology] A process for making propylene from mixed petrochemical feedstocks. Developed by Phillips and acquired by ABB Lummus Global in 1997. First installed at the Karlsruhe oil refinery of MineraloelrafFinerie Oberrhein (Miro) for startup in 2000. 

This process, called OCT (olefin conversion technology), formerly the Phillips Triolefin Process, which utilizes a heterogeneous catalyst system, was originally developed by Phillips Petroleum Co. for the conversion of propene into ethene and butene. The reaction takes place in a fixed-bed reactor over a mixture of the metathesis catalyst W03/S102 and the isomerization catalyst MgO at temperatures above 540 K and an overall pressure of approximately 30 bar [3]. 1-Butene present in the feedstock is isomerized to 2-butene as the original 2-butene is consumed in the metathesis reaction. 

Earls, D Ji., in Handbook of Petroleum Riming Processes, 3rd ed., Meyas, R. A, Ed., McGraw-Hill, New York, 2003,10.3. OCT See Olefins Conversion Technology. 

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