ZA200401484B - Integrated Fischer-Tropsch process with improved alchohol processing capability - Google Patents

Description

Fec2000/771008

CROSS REFERENCE TO RELATED APPLICATIONS

{1} This application claims priority to U.S. Provisional Application Serial No. 60/449,560, filed on February 24, 2003.

FEDERALLY SPONSORED RESEARCH

[2] Not applicable.

REFERENCE TO MI CROFICHE APPENDIX

[3] Not applicable. oo FIELD OF THE INVENTION

[4] The present invention relates to an improved, integrated Fischer-Tropsch process with improved alcohol processing capabilities. More specifically, the invention relates to a Fischer- -

Tropsch process including dehydration of alcohols by passing all or a part of the Fischer-

Tropsch product over alumina, followed by sep aration of the organic and aqueous phases.

ooo LU Wek 4 1 kB 6

BACKGROUND OF THE INVENTION -

[5] Having been first introduced in the early twentieth century, the Fischer-Tropsech reaction for catalytically converting carbon monoxide and hydrogen into hydrocarbons is ver—y well known.

Furthermore, numerous improvements to the process, including the developrment of more Bh efficient and selective catalysts, have been made. All currently known Fischer-Tropsch processes, however, produce a synthetic crude, “syncrude,” which contains primarily paraffins, and olefins with varying amounts of oxygenates. The oxygenates typically includ e primary and internal alcohols, the major portion, aldehydes, ketones and acids. The hea=vy portion of syncrude must be hydroprocessed into usable products. The presence of oxygemates presents certain problems witle processing the syncrude, including a negative impact on hyadroprocessing catalysts and necessi tating an increase in the severity of hydroprocessing. T-he oxygenate content is generally higher in the lower boiling range distillation cuts of the Fisscher-Tropsch product and declines precipitously at the 600°F cut point. One method of avoiding the negative impact of the oxygenates on the hydroprocessing catalysts is to bypass the lower

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EE Les 2004 7 10484 boiling range distillation cuts around the hydroprocessing unit. The lower b oiling range distillation cuts, including any oxygenate content, are then used to reblend the lower boiling range cut with the hydrocracked higher boiling range distillation cut to form the product fuel.

While a bypassed 250-400°F distillation cut has no appreciable negative impasct when re- blended into the product fuel, reincorporation of a bypassed 400°F+ distillation cut: impairs the low temperature properties of the product fuel. Therefore, it is common to hydroprocess the entire 400°F+ fractions, includimg hydrogenation of oxygenates, which has signifi cant impact on catalyst life and causes yield loss. Catalytic hydroprocessing catalysts of noble metals are well known, some of which are described in U.S. Patents 3,852,207; 4,157,294; 3,904,513.

Hydroprocessing schemes utilizing non-noble metals, such as cobalt catalysts, proanoted with rhenium, zirconium, hafnium, cerium or uranium, to form a mixture of paraffins and olefins have also been used. Such hydro treatment, however, is expensive, utilizing high cost catalysts, which are degraded by the presence of alcohol thereby necessitating frequent replenishment.

[6] There remains a need, therefore, for an improved integrated Fischer-Tropsch process in which the alcohol content of the oxygenates produced in the Fischer-Tropsch reacti<on may be wholly or partially removed at a lower cost and without a significant loss of yield.

SUMMARY OF THE INVENTION

[7] In a Fischer-Tropsch process wherein a synthesis gas is catalytically converted into a

Fischer-Tropsch reaction product mixture comprising paraffins and oxygenates and wherein the oxygenates include primary and internal alcohols, the process improvement of the invention includes passing all or part of the Fischer-Tropsch reaction product mixture over at least one bed packed with an alumina catalyst to dehydrate substantially all of the alcohols to their corresponding olefins.

BRIEF DESCRIPTION OF THE DRAWINGS

[8] Fig. 1 is a schematic of an embodiment of the integrated Fischer-Tropsch Process.

[9] Fig. 2 is a schematic of the catalytic dehydration unit of the integrated Fischer—Tropsch process.

[10] Fig. 3 is a schematic of another embodiment of the hydroprocessing unit of the integrated Fischer-Tropsch process. 3

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[11] Fig. 4 is a schematic illustrati ng a hydrocracker/hydroisomerizer unit.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[12] The integrated Fischer-Tropsch process includes processing of synthesis gas to produce a hydrocarbon stream via the Fischer-Tropsch reaction, recovery of the Fischer-Tropsch product, catalytic dehydration of all or part of the Fischer-Tropsch product, and recovery of the hydrocarbons by phase separation. Optional steps in the integrated process include production of a synthesis gas, fractionation or distillation of the Fischer-Tropsch product prior to dehydration and hydroprocessing of part of the Fischer-Tropsch hydrocarbon product. A wide variety of Fischer-Tropsch reactiom processes are known in which reaction conditions, catalysts, and reactor configurations vary. The integrated Fischer-Tropsch process of the invention may be used with any such reaction conditions, catalysts, and reactor configurations. :

For the purposes of the description brelow, one known Fischer-Tropsch synthesis is described.

Other variations of Fischer-Tropsch synthesis are described, inter alia, in U.S. 4,973,453; 6,172,124; 6,169,120; and 6,130,259; the disclosures of which are all incorporated herein by reference.

[13] Three basic techniques may be employed for producing a synthesis gas, or syngas, which is used as the starting material of a Fischer-Tropsch reaction. These include oxidation, reforming and autothermal reforming. As an example, a Fischer-Tropsch conversion system for converting hydrocarbon gases to liquid or solid hydrocarbon products using autothermal reforming includes a synthesis gas unit, which includes a synthesis gas reactor in the form of an autothermal reforming reactor (ATR) containing a reforming catalyst, such as a nickel- containing catalyst. A stream of light hhydrocarbons to be converted, which may include natural gas, is introduced into the reactor alon g with oxygen (Oz). The oxygen may be provided from compressed air or other compressed oxygen-containing gas, or may be a pure oxygen stream.

The ATR reaction may be adiabatic, with no heat being added or removed from the reactor other than from the feeds and the heat of reaction. The reaction is carried out under sub- stoichiometric conditions whereby the oxygen/steam/gas mixture is converted to syngas.

[14] The Fischer-Tropsch reaction for converting syngas, which is composed primarily of carbon monoxide (CO) and hydrogen gas (H;), may be characterized by the following general reaction: 4

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20H; +nCO > (-CHyp)n + nH:0 Be + 2004 148 4

Non-reactive components, such as nitrogen, may also be included or mixed with the syngas.

This may occur in those instances where air, enriched air, or some other non-pure oxygen source is used during the syngas formation.

[15] The syngas is delivered to a synthesis unit, which includes a Fischer-Tropsch reactor (FTR) containing a Fischer-Tropsch catalyst. Numerous Fischer-Tropsch catalysts may be used in carrying out the reaction. These include cobalt, iron, ruthenium as well as other Group oo

VIIIB transition metals or combinations of such metals, to prepare both saturated and unsaturated hydrocarbons. The Fischer-Tropsch catalyst may include a support, such as a metal-oxide support, including silica, alumina, silica-alumina or titanium oxides. For example, a Co catalyst on transition alumina with a surface area of approximately 100-200 m?/g may be used in the form of spheres of 50-150 pm in diameter. The Co concentration on the support may also be 15-30%. Certain catalyst promoters and stabilizers may be used. The stabilizers include Group IIA or Group IIIB metals, while the promoters may include elements from

Group VII or Group VIIB. The Fischer-Tropsch catalyst and reaction conditions may be selected to be optimal for desired reaction products, such as for hydrocarbons of certain chain + lengths or number of carbon atoms. Any of the following reactor configurations may be employed for Fischer-Tropsch synthesis: fixed bed, slurry bed reactor, ebullating bed, fluidizing bed, or continuously stirred tank reactor (CSTR). The FTR may be operated at a pressure of 100 to 500 psia and a temperature of 375° F to 500° F. The reactor gas hourly space velocity (“GHSV”) may be from 1000 to 8000 hr''. Syngas useful in producing a Fischer-

Tropsch product useful in the invention may contain gaseous hydrocarbons, hydrogen, carbon monoxide and nitrogen with H,/CO ratios fromm about 1.8 to about 2.4. The hydrocarbon products derived from the Fischer-Tropsch reaction may range from methane (CH,) to high molecular weight paraffinic waxes containing more than 100 carbon atoms.

[16] Referring to Fig. 1, an overview of the integrated Fischer Tropsch process is illustrated.

Synthesis gas contained in line 1 is fed to a Fischer-Tropsch reactor (FTR) 2. The tail gas of the Fischer-Tropsch product is recovered overhesad in line 3 and the Fischer-Tropsch oil and wax are fractionated and recovered through lines 4 and 5. The product recovered in line 4 is a

Light Fischer Tropsch Liquid (LFTL), and the product recovered in line 5 is a Heavy Fischer

Tropsch Liquid (HFTL). Alternatively, LFTL and HFTL may be further fractionated into at 5

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“ec 2004 71484 least a nominally 30-550°F distillate and S00°F+ bottoms stream. LFTL ancl HFTL may also be fractionated into a number of other fractions as required by the desired product slate.

[17] All or part of the LFTL, which is comprised primarily of C, to Cy, paraffins, is fed into the dehydration unit 6. In the integrated Fischer-Tropsch process, primeary and internal alcohols presemt in the LFTL are dehydrated to yield corresponding olefins. Such conversions illustrated for the case of a primary alcohol by the following reaction:

R-CH,-CH,-OH > R-CH=CH,; + H,O 2). wherein R is arm alkyl group and R-CH,-CH,-OH is an alcohol having a boiling: point such that itis distilled as goart of the LFTL.

[18] Referring now to Fig. 2, a schematic of the dehydration unit of the integrated Fischer

Tropsch process: is shown. The LFTL stream is vaporized in a preheater 20. The vaporized

LFTL stream at a temperature from about 400°F to about 800°F is passed throtagh line 21 into one or more pac ked beds 22 where it passes over activated treated alumina or silica-alumina.

Essentially all of the primary and internal alcohols present in the vaporized LFTL are dehydrated to the=ir corresponding olefins, with conversion rates of at least 95%.

[19] Dehydrati on reaction temperature may range from between about 400° amd 800°F. The vaporized feed fo-r the dehydration unit may be superheated prior to being fed insto packed beds 22 or alternatively, may be heated within packed beds 22. The LHSV of packeci beds 22 may range from about 0.10 hr to about 2.0 hr'. Reaction pressure may be mairtained by the pressure of the accumulator and must be such to vaporize all of the dehwdration feed.

Typically, the presssure may range from between about 0 psia to about 100 psig. The LFTL stream may be mi xed with nitrogen gas or steam prior to or after preheater 20. The nitrogen gas or steam acts teo help I vaporizing heavier components of the LFTL stream.

[20] In an alterraative embodiment, a moving bed of alumina or silica-alumina catalyst may be used. Coking iss an undesirable side reaction in this synthesis. Fluidized beds, slurry beds or ebullating beds m ay be used with continuous batch or semi-batch catalyst removal and regeneration. The catalyst may be removed by one of these methods and regenerated by passing a mixture o fnitrogen and oxygen or air at elevated temperatures over the catalyst. © 30 [21] Depending upon the alumina used, some of the olefins present or produced in packed beds 22 may also be isomerized to internal olefins. Alumina catalysts useful for the dehydration of alcohols are known and include, for example, gamma-alumina, theeta-alumina,

HOUSTON 279990v1 41290-a0001 4USPT | °

- R be eg 20 1] i/ 1 19¢ pacified alumina, and activated alumina. High surface area aluminas are particularly useful in the invention and include those aluminas having a surfzace area of about 100 m%/gm or greater.

Commercially available alumina useful in the integratexd Fischer-Tropsch process include, for example, S-400, which has a surface area of about B35 m?/gm, and DD-470, which has a surface area of about 375 m?/gm. S-400 ad DD-470 are alumina catalysts made and sold by

Alcoa. Alumina catalysts for use in the integrated Fisch er-Tropsch process generally contain at least about 90wt% Al,O;, oxides of silicon and iron present in amounts of less than about 0.1wt%, and oxides of sodium present in an amount of less than about 1 wt%. The alumina catalysts are generally supplied as substantially spherical particles having diameter from about 1/8 to about ¥ inch.

[22] In another embodiment of the invention, molecular sieve or zeolitic molecular sieve forms of the alumina or silica-alumina catalysts may b-e used. For example, silico alumino pheosphate ("SAPO") molecular sieves may be used in becds 22. SAPO molecular sieves contain a 3-dimensional microporous crystal structure having 8, 10, or 12 membered ring structures. Thering structures can have an average pore size ranging: from between about 3.5 angstroms to about 15 angstroms. Other silica-containing zeolitic molecular sieve catalysts, such as ZSM-5, may be used in bed 22.

[23] In an alternative embodiment, all or part of the HFFTL may also be dehydrated. In such cas es, the operating pressure of the accumulator, and thuss the packed beds, should be adjusted to vaporize the HFTL stream.

[24] The advantage of dehydration as a part of the irtegrated Fischer-Tropsch process is imprrovement of yield of useful products. It is known by those skilled in the art that oxygenates in the hydrocracking feed reduce hydrocracking catalyst Rife and therefore, necessitate higher hydxocracking temperatures to achieve the required low temperature properties of a specific boiling range and to maintain conversion per pass. Higher hydrocracking temperatures lead to lower product yields. Moreover, bypassing the Fischer-Tropsch product in the middle distillate range directly to product blending introduces alcohols into the final product. Alcohols are known to have poor low temperature properties, such as freeze point and pour point.

Hydrocracking conditions must be intensified to compens ate for the impact of the alcohols.

Similarly, if the product being bypassed is hydrotreated, it is well known that paraffins generated in hydrotreatment have higher freeze point and wyet again cause deterioration in the 7

HOUSTON 279990v1 41290-00014USPT low temperature properties of the blended product. The inventive integrated Fisher-Tropsch process disposes of the alcohols by converting them into olefins which have beneficial low temperature properties. (25] The dehydrated product is recovered throughm line 24 into condenser 25, where it is condensed. The condensed product will contain aqumeous and organic phases which may be separated in an accumulator 26. Both the organic amd aqueous phases are essentially free of alcohols, the alcohols having been essentially completely dehydrated. The organic phase primarily contains paraffins with some olefins, the olefins arising from dehydration of the alcohols as well as from the Fischer-Tropsch product.

[26] Fig. 3 illustrates an alternative embodiment of™ the integrated Fischer-Tropsch process.

Light and heavy Fischer-Tropsch liquids are combined and fractionated in a distillation column 30. The nominal 30°-600°F product is removed as one or more side-streams, including a nominal 30°-250°F fraction through line 32, a nominal 250°-500°F fraction though line 34, and a nominal 500°F+ fraction through line 35. Only th e 250°-500°F fraction is routed to the dehydration unit 36. The 250°-500°F fraction is sent directly to a product blending area 37 after being dehydrated in dehydration unit 36.

[27] Figs. 1 and 3 both depict a higher boiling fract@on bypassing the dehydration unit and being routed to hydrocracking/hydrotreating units 10 amd 38, respectively. Figs. 1 and 3 also depict the dehydrated product mixture of paraffins arad olefins as also being routed to the hydrocracking/hydrotreating units, which is appropriate= where a fully hydrotreated product is } desired. However, the dehydrated product mixturre may alternatively be separately hydroisomerized or may receive no further hydroprocessing. Fig. 4 depicts such a hydrocracker/hydroisomerizer arrangement. However, any of a number of alternative post- dehydration and higher boiling range fraction treatment schemes may be employed within the integrated Fischer-Tropsch process depending upon the diesired slate of products. For example, referring to Fig. 4, alternative treatment schemes include: a) Hydroisomerization of the dehydrated product; hydrocracking of the higher boiling fraction followed by hydrotreatment. b) No post-dehydration treatment of the dehydrated product; hydrocracking of the higher boiling fraction 8

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C) No post-dehydration treatment of the dehydrated product; hydrocracking of the higher boiling fraction followed by hydrotreatment. d) Hydroisomerization of the dehydrated product; no hydroprocessing of the higher boiling range fraction; reblending of the dehydrated - hydroisomerized product with the highe=r boiling range fraction followed by fractionation; hydrocracking of the bottoms stream of thee fractionation. €) Hydroisomerization of the dehydrated product; hydrocracking of the higher boiling fraction. f) No post-dehydration treatment of the dehydrated product; hydrotreatment followed by= hydrocracking of the higher boiling range fraction. (8) Skeletal rearrangement of dehydrated product in the absence of hydrogen to preserve the olefin content; hydrocracking of higher boiling fraction. (h) No post-dehydration treatment of the dehydrated product; hydrotreatment of the higher boiling fraction.

No post-dehydration treatment of the dehydrated product; hydrotreatment, hydrocracking and hydrofinishing of the higher boiling fraction. (3) No post-dehydration treatment of the dehydrated product; hydrotreatment and hydrocracking of the higher boiling fraction; hydrodewaxing of the unconverted hydrocracker bottoms and hydrofinishing of lubricant basestock (k) No post—dehydration treatment of the dehydrated product; hydrocracking of the higher boiling fraction; hydrotreatment of the unnconverted wax.

[28] These alternative treatment schernes are only some of the variations encompassed by and useful in the integrated Fischer-Txopsch process. Thus, the list above is intended to merely illustrate, and not limit, a portiora of the integrated Fischer-Tropsch process. Possible process conditions and parameters for hy droisomerizing, hydrotreating and hydrocracking the relevant hydrocarbon streams are well known in the art. One example of hydroprocessing conditions and parameters is described in Australian Patent No AU-B-44676/93, the disclosure of which is incorporated herein by referemce. A large number of alternative hydroprocessing conditions and parameters are also known in the art and may be useful in connection with the 9

HOUSTON 279990v1 41290-0001 4USPT integrated Fischer-Tropsch process described herein. Therefore, incorporation of the above- referenced Australian patent is not intended to limit the inventive process. :

[29] The processing schemes listed above may be useful in fulfilling various product slate demands and in preparing a number of products. Schemes (2), (b), (c), (d), (e), (D), (8), and (k) are useful for producing ultra-clean synthetic middle distilRate fuels. Schemes (c) and (h) are useful for producing high grade synthetic waxes. Scheme=s (i) and (j) are useful for making high quality synthetic lubricants. In addition, schemes (b»), (¢), (£), (h), (i), (§), and (k) are useful for making olefin/paraffin mixtures as dehydrated product which can be used as feedstocks for (I) linear olefins, (II) linear and branched alco hols, (III) feedstock for linear alkyl benzenes production, (IV) high an low octane gasoline blendstocks, and (V) single product middle distillate fuel feedstocks.

[30] In one useful embodiment of the integrated Fischer Tropsch process, the syncrude is manufactured from autothermal reformation of methane containing gas, generally in the form of coal or natural gas, in the presence of air. The resulting syncrude is comprised primarily of paraffins, olefins and oxygenates in the form of alcohols, with the alcohols being primarily primary alcohols. The dehydration component of the integrated Fischer Tropsch process selectively treats the alcohols and converts the alcohol component into the corresponding olefins. Thus, the product in this embodiment of the integrated Fischer Tropsch process is a rnixture of paraffins and olefins with no alcohol content. Thus, the resulting Fischer Tropsch product comprises only two moieties, paraffins and ol efins, which are rheologically, toxicologically, conductively, oxidatively and reactively simil ar. This Fischer Tropsch product may then be fractionated to obtain carbon number cuts for use in a wide variety of applications where no oxygenate, or alcohol, content is highly desirable. For example, a Co — Cy; fraction may be used as feedstock to produce detergent grade linear alkyl benzenes and synthetic habricants, a C4 — C7 fraction may be used as feedstock for production of drilling fluids, chloroparaffins, specialty alkylates and synthetic lubricants, a €;s~ Cg fraction may be used as feedstock for specialty additives and transformer oil additives, and a C4 — Cy fraction may be ussed as feedstock for naphtha formulation or as a feed to oligomerization. 10

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Example 1

[31] A pilot installation consisting of two distillation columns was used to produce Ce.10 naphtha, Cyg.13 light kerosene, and C350. drilling fluid feeedstock streams. The columns were fed approximately 3400 g/hr of liquid Fischer-Tropsch oil. Fischer-Tropsch oil had approximately the following composition: a | <01 6 | 03 7 | 10 8 | 29 9 [| s9 | 81 13 | 92 14 | 84 19 | 46 21 | 30 24 | 12

Total 100.00 10 [32] Fischer-Tropsch oil was fed into the first column and C;; and lighter materials were distilled overhead. The column conditions were: 10 psig pressure, 480°F feed preheat temperature, 407°F overhead temperature, 582°F bottoms temperature. The first column had approximately 98 inches of Sulzer Mellapack 750Y packings. The overheads of the first column was fed into the second column operating at 12 psig pressure, 370°F overhead temperature and 437°F bottoms temperature. The second column is packed with 28 inches of Sulzer EX packing. The bottoms of the second column constituted the product Cg. ; light kerosene stream. The bottoms of the first column constituted Ci3_2¢+ heavy diesel and drilling fluid 11

HOUSTORN 279990v1 41290-00014USPT feedstock. The compositions of Cyg.13 light kerosene stream (Fe ed A) and Cy3.50+ (Feed B) are shown in Tables 1 and 2, respectively.

TABLE 1 otal n-paraffins, isoparaffins, olefins and alcohols Mass % cs 1 oa co hae cro es cu mst cz ses cs har ce ea

I TTY

TABLE 2 otal n-paraffins, isoparaffins, olefins and alcohols [Mass % ci: her cr bes clo: 0 kr c. hoa ca: les

I TY

Example 2

[33] 30 cc/tar of a Feed A from Example 1 was fed via a syringes pump and mixed with 20 cc/min of nitrogen. The gas/liquid mixture was introduced upflow into a vessel packed with stainless steel mesh saddles, where the liquid was vaporized ancl superheated to reaction temperature of” 560°F. The vaporized feed was fed upflow into a reactor packed with 1/8 Alcoa

S-400 alumina catalyst and suspended in a heated sandbath. The sandbath was maintained at the reaction termiperature and ebulated by air. Reactor LHSV was mai_ntained at about 0.26 hr. 12

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Ve c & 20 24 /

The reactor outlet was condensed and Product A and water by-product was collected in a product accumulator. System pressure was maintained by contreolling the product accumulator overhead pressure at 50 psig. Water layer was drained and product analyzed in a HP 5890

Series II «GC with a 60 m RTX1 capillary column with a 0.32 mm bore and 3-micron film thickness. The compositions of the feed and Product A are reported in Table 3. The product was also analyzed on a '"H NMR 300 MHz JOEL analyzer, confirming complete absence of alcohols.

Example 3

[34] 15 <c/br of Feed A from Example 1 was processed in a be nchscale process described in

Example 2. The feed was vaporized and superheated to 6 50°F. Reactor LHSV was approximately 0.13 hr'. Composition of Product B from this example is reported in Table 3. 'H NMR analysis confirmed absence of alcohols in the product.

TABLE 3

Product

Product A B

OTAL I EE FU

N-P.ARAFFIN 80.64 80.23 79.90

ALPPHA OLEFIN

INTERNAL OLEFIN

BRANCHED PARAFFIN

ALCOHOL mass% | 3.68 | 000 | 0.00 mas% | 100.00 | 10000] 10000

Example 4

[35] Feed A from Example 1 was spiked with approximately 5% of hexanol, composing

Feed A’ and fed at 15 cc/min into a benchscale process described im Example 3. Nitrogen feed was maintairaed at 10 cc/min. Composition of Product C from this example is reported in Table 4. "HNMR analysis confirmed absence of alcohols in the product. 13

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TABLE 4

TT FeedA | ProduetC

N-PARAFFIN 75.12 75.14

ALPHA OLEFIN 10.75

INTERNAL OLEFIN

BRANCHED PARAFFIN

ALCOHOL mass% | 803 [ 000 lmass% | 10000 100 .00

Example 5

[36] Feed B from Example 1 was fed into a process described in Example 4. The reaction temperature was maintained at 675°F and the outlet pressure was maintained zat about 5 psig.

The reaction Product D is shown in Table 5.

TABLE 5 0000000] FeedB | ProduxtD gotAL © [N-PARAFFIN Mass % [82.46 82.87

ALPHA OLEFIN

INTERNAL OLEFIN Mass% 275 B68

BRANCHED PARAFFIN 10.10 ~ |ALCOHOL Mass% [45s Jo.oo live 100.0

Units which are used in this specification and which are not in accordance with the Sl system may be converte=d to the Si system with the aid of the following table: degree °C = (°F-32)5/9 pound per square inch absolute (psia) = 6,895x10°Pa

Pa = 1psi gauge (psig)+ 14.7 inch = 2,54x10m 14

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Claims (1)

1. CLAMS: Be 200171188

   1. A Fischer-Tropsch process wherein a synthesis gas is catalytically converted into a Fischer-Tropsch reaction product mixture comprisin g paraffins and oxygenates and wherein the oxygenates include primary and internal alcohols, the process comprising: (a)) passing all or part of the Fischer-Tropsch reaction product mixture over at least one bed packed with an alumina catalyst to dehydrate substantially all of the alcohols to their corresponding olefins.

   2. The process of claim 1 further comprising the stepp of (ag) vaporizing all or part of the Fischer-Tropsch reaction product mixture before step (a;)

   3. The process of claim 1 further comprising the steps of: (b) condensing a dehydrated product; (c) separating aqueous and organic phases of the dehydrated product.

   4. The process of claim 1 further comprising the step of hydroisomerizing all or part of the organic phase.

   5. The process of claim 1 wherein the reaction temperature of dehydration in step (a) is between about 400°F (204°C) and about 800°F (427°C).

   6. The process of claim 1 wherein the alumina is a hi gh suffice area alumina,

   7. The process of' claim 6 wherein the alumina is selected from the group of gamma-alumina and theta-alumina

   8. The process of claim 1 wherein the alumina, is passivated alumina.

   9. The process of claim 1 wherein the reaction tempe rature of dehydration in step (a;) is between about S00°F (260°C) and about 700°F (371°C).

   10. The process of claim 1 wherein the reaction temp erature of dehydration in step (a) is between about 550°F (288°C) and abou t 675°F (357°C)

   11. The process of claim 1 wherein the alumina catal yst is activated alumina

   12. The process of claim 1 wherein the LHSV of 'the packed bed is between about 0,1 hr” and about 10.0 hr".

   - 13, The process of claim 1 wherein the LHSV of the packed bexd is between about 0 12 hr” and about 2.0 hr”. 14, The process of claim 1 wherein step (a) is operated at a prezssure of from about 0 psia to (101, 3hPa (a)) about 200 psig (137.9hPa (g)) The process of claim 3 wherein the Fischer Tropsch reactiosn product mixture comprises from about Owt% to about 95wt0% olefins 16 , The process of claim 3 wherein the Fischer Tropsch reaction product mixture comprises from about 0.5 to about 40wt% oxygenates. 17 The process of claim 16 wherein at least 90wt% of the oxyg enates are primary and internal alcohols.

   18. An integrated Fischer Tropsch process comprising the steps of: (a) producing a synthetic crude by Fischer-Tropsch reaction of synthesis gas; B) fractionating the synthetic crude at least into a li ght Fischer Tropsch liquid, and a heavy Fischer Tropsch liquid; and (c) reacting at least a part of the light Fischer Tropsch liquid over an alumina catalyst to dehydrate alcohols in the light Fischer Tropsch liquidl to corresponding alpha- and internal-olefins and forming a dehydrated product.

   19. The process of claim 18 further comprising the step of: (d) fractionating the dehydrated product into at least a naphtha. fraction, and at least one middle distillate fraction, (121°C-316°C).

   20. The process of claim 19 wherein the naphtha fraction is fromm 30-300°F (-1°C - 149°C)

   21. The process of either of claims 19 or 20 wherein the middle distillate fraction is from 250 - 600°F (121°C - 316°C)

   22. The process of claim 18 further comprising the step of: (e) hydroisomerizing all or part of the middle distillate.

   23. The process of claim 18 further comprising the step of: (f) hydroprocessing all or part of the heavy Fischer Trops ch liquid.

   24. The process of claim 1 wherein the synthesis gas is prepared rom a gas comprising methane.

   . ) 25. The process of claim 24 wherein the synthesis gas is produced by atatothermal reformation .

   26. The process of claim 25 wherein the autothermal reformation feedstock comprises 190% to 60% N,

   27. The process of claim 24 wherein the gas is natural gas,

   28. The process of claim 24 wherein the gas is coal gas,

   29. The process of claim 1 wherein at least 95wt% of alcohols present ir the Fischer Tropsch reaction product are converted to olefins in step (a; 0)

   30.The process of claim 1 wherein the dehydrated product from step (a;)» contains substantially no alcohols

   31.The process of claim 1 wherein the dehydrated product from step (a; d contains substantially no oxygenates,

   32. The process of claim 18 wherein at least 95w% of alcohols present ir the light Fischer Tropsch liquid are converted to olefins in step (c).

   33. The process of claim 18 wherein the dehydrated product from step (c=) contains substantially no alcohols.

   34. The process of claim 18 wherein the dehydrated product from step (¢ ) contains substantially no oxygenate s.

   35. The process oof claim 18 wherein the synthesis gas is prepared from a gas comprising methane.

   36. The process of claim 35 wherein the synthesis gas is produced by autothermal reformation.

   37. The process o f claim 36 wherein the autothermal reformation syngas product comprises 10% to 60% NN.

   38. The process of claim 1 wherein step (a) is conducted over a moving bed of alumina. catalyst and fuarther comprising continuous catalyst regeneration.

   39. The process of claim 38 wherein the moving bed is selected from the group of ebullating beds, slurry bed and a fluidized bed.

   " 40.The Process of claim 1 wherein the catalyst is selected from the group of silica-alumina, silico>-alumino phosphate, and mole sieves.

   41. The gorocess of claim 40 wherein the mole sieve is a zeolite.

   42. The process of claim 18 wherein step (c) is conducted over a moving beed of alumina catalyst and further comprising continuous catalyst regeneration.

   43. The process of claim 42 wherein the moving bed is selected from the group of ebullating beds, slurry bed and a fluidized bed.

   44. A process according to claim 1, substantially as herein described with reeference to any of the illustarative Examples.

   45. A proscess according to claim 18, substantially as herein described with reference to any of the illustrative Examples. DATED THIS 24™ DAY OF FEBRUARY 2004 APPLICAINTS PATENT ATTORNEYS