Title of Invention	"PRODUCTION OF OLEFINS FROM BIORENEWABLE FEEDSTOCKS"
Abstract	A process for producing olefins from biorenewable feedstocks has been developed. The process comprises first pretreating the feedstock, e.g. vegetable oil, to remove contaminants such as alkali metals and then cracking the purified feedstock in a fluidized catalytic cracking (FCC) zone operated at conditions to provide C<sb>2</sb>-C<sb>5</sb> olefins.

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BACKGROUND OF THE INVENTION [0001] Fluid CiOalytic Cracking (FCC) is one method which is used to i»XKiuce olefins, eipecdaUy pn^ylnie, from heavy oude fi:actions. Thore are rqports in the literatioe that vegetable oils sudi as cairala oil could be processed using FCC to give a l^rdFOcaibon sttem useful as agasoline fijei. [0002] Applicants have developed a process which sucoessfully converts vegetable oilS and greases to C1-C5 olefins. The process involves first removing contaminants auch as alkali metals and then taking the purified feedstock, flowing it through an FCC zone and colleding a product stream comprised of olefins. DETAILED DESCRIPTION OF THE INVENTION [0003] The feedstocks which can be used in the practise of the present invention are termed biorenewable feedstocks and con:comprise any of those which comprise primarily tri-glycerides and free futty adds (FFA). Examples of these feedstocks include but are not limited to canola oil, com oil, soy oils, inedible tallow, yellow and brown greases, etc. The tri-giycoides and FFAs contain aliphatic hydrocarbon chains in their structure having 14 to 22 carbons. Another example of a bio-renewabie feedstock that can be used in the present invention is tall oil. Tall oil is a by-product of the wood processing industry. Tall oil contains estors and rosin acids in addition to FFAs. Bonn acids are cyclic carboxylic acids. However, these biorenewable feedstocks also contain contaminaats such as alkali metals, e.g. sodium and potassium,phosporus as well as ash, water and detergents. [0004] Accordingly, the first stqp in the presoit invention is to remove as much of these contaminants as possible. One pretreatment step involves contacting the biorenewable feedstock with an ion-exchange resin in a pretreatmmt zone at pretreatment conditions. The ion-exchange resin is an acidic ion exchange resin such as Amberlyst -15 and can be used as a bed in a reactor through which the feedstock is flowed through, either upflow or downflow. The conditions at which the reactor is operated are well known in the art [0005] Another-means for ronoving contaminants is a mild acid wash. This is carried out by contacting the feedstock with an acid such as sulfuric, acetic, nitric or hydrochlock add in a reactor:. The acid and feedstock can be contacted either in a batch or continuous process. Contacting is done with a dilute acid solution usually at ambient temprature and atmosphoric pressure. If the contacting is done in a continuous manner, it is usually done in a counter currant manner. [0006] Yet another- means of removing metal contaminants from the feedstock is throug the use of guard beds which are well known in the art These can include alumina guard beds either with or wit out dnnetallation catalysts such as nickel or cobalt [0007] The purified effluent from the pretreatment zone is now flowed to an FCC zone where the hydzocarbonaceous components are cracked to olefins. Catalytic cracking is accomplished by contacting hydrocarbons in a reaction zone with a catalyst compost of finely divided particulate material. The reaction is catalytic oacking, as opposed to hydrocracking, and is carried out in the absence of added hydrogen or the consunqitioa of hydrogen. As the cracking reaction proceeds, sidstantial amounts of coke are deposited on the cataly The talyst is regenerated at higjh tenq)eratures by burning finm the catalyst in a regeneration zone. Cdce-contaming ca to herein as "coked catalyst", is continually transported fiom the reaction Txmc to the regasioaticHi zone to be legeoBtated and replaced by essraxtially cdke-frce regena:ated catalyst fixxn tt» regeneration ze. Fluidization of the cataly particles by various gase(His streams allows the tnmsoit of catalyst between the reactii zone and rqgenerotkm seme. Methods for aadking hydrocarbons in a fluidized stream of catalyst, transporting catalyst between reaction and regeaaraticm zones, and cconbusting coke in the regenerator are well known by those skilled in the art of FCC processes. {0008] An arrangement wfaidb can make up tibe FCC zfHieoftfaepresait invention is wn in US 6,538,169 which is inccnporated in its entirety by referoice and comprises a separator vessel, a regenerator, a blending vessel and a votical riser that provides a {meumatic conveyance zone in which conversion takes place. The catalysts which can be used in the present process are any of those well known in the ait and comprises two components that may or may not be on the same matrix. The two compooents are circulated througiout the entire system. The first compcment may include any of the well-known catalysts that are used in the art of fluidized catalytic asking, such as an active amorphous clay-type catalyst and/or a high activity, crystalline molecular sieve. Molecular sieve catalysts are prefetred over amorphous catalystg because of tiieir miidi-improved selectivity to desired products. Zeolites are the mostcammaDly used molecular sieves in FCC processes. Prefoably, the first catalyst compffnoftocw^prises a large pore zeolite, sach as a Y-type zeolite, an active alumina material, a bmder material, conyrimngeitfaeriiUca or alumina an kaolin. [M09] 11]ezeoticmofaxlarskwKiproiatef the first catalyst component abauLd hawe a large average pore size. Typically, molecular eves with a large pore size have poses with openings of eaterlhai 0.7 nm in effective diameter defined by greato: than 10 and ically 12 membered rings. Pore Size Indices of large pores are above 31. Suitable large pore zeolite compcmcnts include synthetic zeolites such as X-type and Y-type zeolites, mordoiite and &i^asite. We have found tiiat Y zeolites with low rare earth conteait are prefexred in the first catalyst component Low rare earth content denotes less than or equal to 1.0 wt-% rare eardi oxide on the zeolite portion of the catalyst. Octacat catalyst made by W.R. Grace & Co. is a suitable low rare earth Y-zeoIite catalyst [0010] The second catalyst compfxaeat comprises a catalyst containing, medium pore zeolites etxealified by ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48, and otfacr similar materials. US 3,702,886 describes ZSM-5. Other suitable medium pare zeolites Include fertimte, oionite, and ST-5, developed by Petroleos de Votczuela, S.A. sec(Mid catalyst oon^nent preferably disperses the medium pore zeolite on a matrix comprising a binder matraial such as silica or alumina and an inert filler matoial such as kaolin. Hxe second component may also comprise some other active material sudi as Beta zeolite. These catalyst compositions have a crystalline zeolite content of 10 to 25 wt-% or more and a matrix material contoit of 75 to 90 wt-%. Catalysts containing 25 wt-% crystalline zeolite material are prefored. Catalysts with greater crystalline zeolite content may be used, provided they have satisfactory attrition resistance. Medium pore zeolites are characterized by having an effective pore opening diameter of less tiian (x equal to 0.7 nm, rings of 10 or fewer membocs and a Pore Size Index ofless than 31. [0911] The total catalyst (xxnposition should contain 1 to 10 wt-% of a medium p(He zecdite wdth greate than or equal to 1.75 wt-% bong pfefored Whffl the second catalyst cooipeixt cootaias 25 wt-% crystalline zeolite, the conqwsition contains 4 to 40 wt-% of (he second catalyst o(»np(nimt wilh a preied content of greato: than or 6qualto7wt-%. ZSNf-5 and ST-S type zeotes are particuufyprafored since their high coke itaistivitty wiU tend to preserve active oracking sdtes as (he cat makes mi^tqite passes ferougjhtteriaer, thereby mairitaim catabist oomponeiit will cmj^priae tibe balance of the catalyst composition. The relative proprtiaasof the first and aeoood cornpooents in the catalyst c(xiqwntim will not substantially vary tibroubout FCC unit [0012] The high concentraticn of medium pore zeolite in tiw second component of the catalyst composition im{ax}ves sdectivity to ligjbt olefins by furtha cracking the lighter tha range molecules. But at the same tinse, the resulting smaller coiKiOXbaticKa of the first catalyst compcxient still exhibits suflSdoit activity to maintain conversion of the heavia feed molecules to a reasonably high level [0013] Cracking of tiie feedstock takes place in Hae riser section of Ae FCC zone. Feed is introduced into the riser by a iK)zzle resulting in the rapid vaporization of the feed. Before contacting the catalyst, the feed will ordinarily have a temperature of 149^to316°C(300Tto«XrF)- The catalyst is flowed fiom a blending vessel to the riser v(4iece it contacts the feed for a time of 2 seconds (M: less. [0014] The blended catalyst andmacted feed ap are then discharged torn the of Ifae riser through an itlet and 8q)arated into a cradlced product vapor stream including olefins and a collection of catalyst particles covered with substantial quantities of coke and gooerally referred to as "coked catalyst." In an effort to minimize the contact time of the feed and the catalyst may inromote further conversi(m of desired products to undesirable o&nst {Htxlucts, any arrangement of separators such as a swirl arm arrangement can be used to remove coked catalyst from the product stream quickly. The separator, e.g. swiri arm sq>arator, is located in an vpper portion of a chamber with a stripping zone situated in the loww portion of the chamber. Catalyst separated by the swirl arm arrai^;einQat drops down into the stripping zone. The cracked product vapor stream comprising cracked hydrocarbons including light olejQns and some catalyst exit the chamber via a conduit ^lich is in communication with cyclones. The cyclones ranove remaining catalyst particles fiiom the product yapoc stream to reduce partide cenlntions to low levdb. The product vapw stream then exits the to sqwratiiig vessel. Ortalystaqmated by the cyclones is icioned to the sqnrating vessel and then to tiiestcipiqg zone. Hie strijnngzomianovesadsocbedhydrocarixnis from tibe sur&e of the catalyst fay cotrnternnmnent contact wiA sterna. [0015] A first poitian of tiae ooked catalyst is recycled to the riser without first vrndagaiag tcgeasai&oai. A second portion of tiie coked catalyst is regenteated in (he regenerato bdFore it is ddivend to the riser. The first aod seooid portions of the catalyst may be blended in abkading vessel befi»e introductum to die riser. The recycled catalyst may be withdrawn fix}m the string zcme for transfor to the blending vessel. (0016] The second portion of the coked, stripped catalyst is transported to the regeneration zone. In the regeneration zone the cked catalyst undergoes regeneration by combustion of o on the sur&ce of the catalyst particles by contact with an oxygm-containing gas. Theen-containing gas enta:s the bottom of the regenerator and passes through a dense fiuidizing bed of catalyst Flue gas cisisting prutnarily of CO2 and peAaps containing CO passes iqiwanlly firom the dense bed into a dilute phase of tbs renenttor. A sqMurator, sudbi as cycHies or other means, remove entrained catalyst particles fixmi the rising flue gas before the flue gas exits the vessel through an outiet CcHnbustion of coke from the catalyst particles raises the temperatures of tiie catalyst such is withdrawn fim the regeaerator and flowed to a blending vessel. Fiuidizing gas passed into the bloiding vessel contacts the catalyst and maintains the catalyst in a fluidized state to bloid the retried and regenerated catalyst [0017] The regenerated catalyst which is relatively hot is cooled by the unregenerated, coked catalyst which is relatively cool to reduce the temperature of the regenerated catalyst by 28° to 83°C (50" to 150T) depending upon the regenerator temperature and the coked catalyst recycle rate. The ratio of recycled catalyst to regenerated catalyst entering the bl«iding zone will be in a Inoad range fiom 0.1 to 5.0 and more typically in a range from 0.3 to 3.0. Preforably, the blmded catalyst will comprise a 1:1 ratio of recycled catalyst to regenerated catalyst. [0018] Regenerated catalyst firom the regraierator will usually have a temperature in a range from TT to 760: (1250° to 1400°F) and, more typically, from 699» to 760°C (1290" to 1400T). Hie tempetature of the recycled catalyst portion will usually be in a range from SIC to 621"C (950" to 1150T). The relative proportions of the recycled and regenerated catalyst will determine the tonperature of &e bleaded catalyst mixture that entas the riser. The biended omalyst mixture will dually ru from 593" to 704"C (U00"tol300T). [0019] partial pleasure operates to favor the production of ligt olefins. Accordingly, the riser jxessure is set at 172 to 241 kPa (25 to 35 psia) with a hydrocarfocxLiMitial pressure of 35 to 172 kPa (5 to 25 psia), with a preferred hydrocarbon partial pressure of 69 to 138 kPa (10 to 20 psia). This relatively low partial pressure for hydrocarbon is achieved by using steam as a diluent to the extent that the diluent is 10 to 55 wt-% of feed aiKl preferably 15 wt-% of feed. Other diluents such as dry gas can be used to reach equivalent hydrocarbon partial pressures. [0020] The temperature of the cracked stream at the riser outlet will be 510" to 621"C (950° to 1150T). However, we have found that risw outlet temperatures above 566"C (1050T) make more dry gas and more olefins. Whereas, risor outlet temperatures below 566"C (1050T) make less ethylene and propylene. Accordingly, it is preferred to run the FCC process at a preferred taiqerature of 566"C to 630"C, prefoxed prsure of 138 kPa to 240 kPa (20 to 35 psia). Ano^fao- condition for the process is the catalyst to oil ratio which can vary from 5 to 20 and preferably from 10 to 15. [0021] Although as seated, the feed is nomudly introduced into the riser section of the FCC zone, it is also wi&in the scope of the presoit invention that the efiQuent from the {xe-treatment zcne introduced into the lifr section of the FCC reactor. The temperature in tibe lift section will be v«y hot and range fiwm 7(X)"C (1292"F) to 760"C (1400"F) witfi a catalyst to oil ratio of 100 to 150. It is anticipated that introducing the oil feed into the lift section will produce considerable amounts of propylene and ethylene. [0022] Vac following examples are jxesoited in illustration of this invoition and are not intraded as undue limitations on &e gomaliy broad scope of the invention as set out in the aeoded claims. EXAMPLE {0023] Catalytic aaddng of soybean oil vms tested using an advanced cracking evaluation pilot plant A commercial fluid catalytic catalyst from W.R. Grace, IIK:. wasused. Tbe soybean oil was obtained frnAldrichC3innical Co. and gas and liquid hydrocarbon products were analyzed by gas chromatography. The analyses did not include orgea bidaaoe nor water analysis. TheTeactiaawasrunat538C (1000T)atcatalyrt: ratio of 3:1 andaWHSV(hr-')of 3 hr-. [0024] Based en dtfae data, calculatioDS wcic carried out to detmninc convulsion at more severe omditions yAash are a tranperature of 565 (l0SOT), a catalyst:oil ratio of 10/1 and 10% steam. [0025] Tltf actual and calculated convosions are presoited below. Actual and Calculated Cracking Conversions for Soybean Oil (TALE REMOVED) 'LCO is light cycle oil which boils between 220-343'C CSO is clarified sluny oil which boils between 343 and 538'C 6 WE-CLAIM - 1. A process for the catalytic cracking of biorenewabie feedstocks comprising first treating the feedstock in a pretreatment zone at pretreatment conditions to remove at least a portion of contaminants present in the feedstock and produce an effluent stream; flowing the effluent from the pretreatment zone to a fluid catalytic cracking zone whore the effluent is contacted with a cracking catalyst at cracking conditions to provide a product stream comprising C2-C5 olefins and hydrocarbons useful as gasoline fuels. 2. The process of claim 1 where the pretteatment step comprisecontacting the feedstock with an acidic ion exchage lesin. 3. The process of claim 1 where the pretreatment step comprises contacting the feedstock with an acid solution. 4. The process of claim 1 where the cracking conditions include a temperature of 566°C (1050°F) to 630°C (1166oF), a pressure of 138 kPa (20 psia) to 240 kPa (35 psia) and a catalyst to oil ratio of 5 to 20. 5. The process of claim 1 where the effluent is injected into the lift section of the fluid catalytic cracking zone. 6. The process of claim 5 where the temperature in the lift section varies from 700oC (1292D to 760oC (1400°F). 7. A process for the catalytic cracking of biorenewabie feedstocks, substantially as hereinbefore described with reference to the foregoing description and example.

Documents:

1968-delnp-2009-abstract.pdf

1968-delnp-2009-Assignment-(21-01-2014).pdf

1968-delnp-2009-Claims-(21-01-2014).pdf

1968-delnp-2009-claims.pdf

1968-delnp-2009-Correspondence Others-(15-05-2014).pdf

1968-delnp-2009-Correspondence Others-(21-01-2014).pdf

1968-delnp-2009-Correspondence-Others-(06-11-2013).pdf

1968-DELNP-2009-Correspondence-Others-(22-09-2009).pdf

1968-delnp-2009-correspondence-others.pdf

1968-delnp-2009-description (complete).pdf

1968-delnp-2009-form-1.pdf

1968-DELNP-2009-Form-18.pdf

1968-delnp-2009-form-2.pdf

1968-delnp-2009-form-26.pdf

1968-delnp-2009-Form-3-(06-11-2013).pdf

1968-DELNP-2009-Form-3-(22-09-2009).pdf

1968-delnp-2009-form-3.pdf

1968-delnp-2009-form-5.pdf

1968-delnp-2009-GPA-(21-01-2014).pdf

1968-delnp-2009-pct-210.pdf

1968-delnp-2009-Petition-137-(21-01-2014).pdf