摘要:
The average cycle propylene selectivity of an oxygenate to propylene (OTP) process using one or more fixed beds of a dual-function oxygenate conversion catalyst is substantially enhanced by the use of moving bed reactor technology in the hydrocarbon synthesis portion of the OTP flow scheme in lieu of fixed bed technology coupled with the selection of a catalyst on-stream cycle time of 200 hours or less. Those provisions hold the build-up of coke deposits on the catalyst to a level which does not substantially degrade dual-function catalyst activity, oxygenate conversion and propylene selectivity, thereby enabling maintenance of propylene average cycle yield at essentially start-of-cycle levels. The propylene average cycle yield improvement enabled by the present invention over that achieved by the fixed bed system of the prior art using the same or a similar catalyst system is of the order of about 1.5 to 5.5 wt-% or more.
摘要:
The present invention comprises a process for conversion of oxygenates to olefins comprising contacting within a reactor the oxygenates with a catalyst to produce light olefins and wherein the reactor comprises at least two zones, a first zone wherein gas circulates at a faster rate than a second zone wherein a gas circulates at a slower rate; and inserting a quantity of inert gas into the second zone to increase circulation of any materials located in said second zone. The invention prevents accumulation of undesirable by-products within stagnant zones within the reactor and reduces the amount of coke deposited on catalyst or on surfaces within these zones.
摘要:
The present invention comprises a process for removal of oxygenates from a paraffin-rich or olefin-rich paraffin stream which comprises passing a feed stream, comprising one or more C10 to C15 feed paraffins or C10 to C15 olefin-rich paraffin stream and one or more oxygenates through an adsorbent bed comprising one or more adsorbents selected from silica gel, activated alumina and sodium x zeolites to remove essentially all of said oxygenates; and recovering said paraffins. A second adsorbent bed may be employed to more thoroughly remove these oxygenates.
摘要:
A hydrocarbon feedstock is catalytically reformed in a sequence comprising a first bifunctional-catalyst reforming zone, a zeolitic-reforming zone containing a catalyst comprising a platinum-group metal and a nonacidic zeolite, and a terminal bifunctional catalyst reforming zone. The process combination permits higher severity, higher aromatics yields and/or increased throughput relative to the known art, and is particularly useful in connection with moving-bed reforming facilities with continuous catalyst regeneration.
摘要:
An integrated process to produce diisopropyl ether from propane has been developed. In a first reaction zone the propane in a feedstock, after any hydrocarbons containing four or more carbon atoms are removed from the feedstock via fractionation, is dehydrogenated in the presence of a dehydrogenation catalyst to form propylene. After removing hydrogen, the propane and propylene mixture generated in the first reaction zone is separated into a propane enriched stream and a propylene enriched stream where the propylene enriched stream contains at least 65 mass % propylene. The propane enriched stream is recycled to the feedstock fractionation unit, and the propylene of the propylene enriched stream is reacted with water in a second reaction zone in the presence of an acidic catalyst to form isopropyl alcohol which is concurrently reacted with propylene to produce diisopropyl ether. A portion of the second reaction zone effluent is recycled to the second reaction zone, and the remainder may be collected or further separated to provide a high purity diisopropyl ether product. A variant to produce high purity propylene as well as diisopropyl ether is also discussed.
摘要:
An apparatus for contacting a bed of particulate material with a cross flowing fluid, which maintains the bed of particulate material within a retention volume. The apparatus includes partitions for retaining particles, with apertures disposed within the partitions. The apertures are covered by louvers that extend above the edges of the apertures to prevent solid particles from spilling through inlet apertures.
摘要:
A process and catalyst are presented for the selective hydrogenation of branched diolefins and acetylenes to olefins. The process uses a catalyst having large pores, and a minimal amount of micropores. The catalyst is designed to have minimal diffusional resistance through the large pores, and to minimize the hydrogenation of olefins to paraffins.
摘要:
An improved process and system for the endothermic dehydrogenation of an alkane stream is described. The process and system of the present invention comprise a back-mixed fluidized bed reactor. The alkane stream is dehydrogenated in a single reactor stage by contacting the alkane stream with a back-mixed fluidized bed of catalyst. Deactivated catalyst is withdrawn from the back-mixed fluidized reactor and heated to produce hot regenerated catalyst. The hot regenerated catalyst is returned to the back-mixed fluidized bed reactor at a rate sufficient to maintain the back-mixed fluidized bed reactor at substantially isothermal conditions.
摘要:
An apparatus is for directing a fluid into a radial reactor is and which maintains a bed of solid particulate material within a reactor. The apparatus comprises a duct for directing fluid into a reactor and has a screenless face for the egress of the fluid, while providing for the retention of solid particles.
摘要:
Integrated processes for making detergent range alkylbenzenes from C5-C6-containing feeds involve feed pretreatment and/or selective hydrogenation to enable acceptable quality alkylbenzene production at attractive capital and operating costs.