JP2011063811A - High purity olefinic naphtha for production of ethylene and propylene - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an olefinic naphtha and a process for producing lower olefins from this naphtha. <P>SOLUTION: In the process for producing lower olefins, preferably ethylene, at least a portion of a hydrocarbon source is converted to synthesis gas and at least a portion of the synthesis gas is converted to an olefinic naphtha by a Fischer-Tropsch process. At least a portion of the olefinic naphtha is converted in a naphtha cracker to a product stream comprising lower olefins, and at least a portion of the lower olefins from the product stream of the naphtha cracker are recovered. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

[Interrelated applications]
This application is co-filed with US patent application Ser. No. 10 / 355,110 (case number 005950-824) entitled “High Purity Olefin Naphtha for the Production of Ethylene and Propylene” and “Ethylene and Propylene”. No. 10 / 354,957 (case number 005950-825), entitled “High Purity Olefinic Naphtha for Production”.

  The present invention relates to an improved technique for producing lower olefins from high purity olefinic naphtha. More specifically, the present invention converts an inexpensive hydrocarbon resource from a remote location to a high-purity olefinic naphtha, transports the olefinic naphtha to a second facility, and then converts the olefinic naphtha to The present invention relates to a method for producing a lower olefin by treatment.

  Lower olefins, especially olefins having 2 to 4 carbon atoms, are suitable starting materials for a number of chemical processes including, for example, alkylation, oligomerization, and polymerization processes. The production of lower olefins from cracked hydrocarbon feeds is a well-known method and has been applied industrially in many petrochemical production facilities. Typically, crude distillate fractions and ordinary crude naphtha fractions are used as hydrocarbon feeds in the naphtha cracker process for producing ethylene.

  For industrial reasons, a naphtha cracking process with high selectivity for lower olefins, especially ethylene, is required. There is also a need to produce ethylene from hydrocarbon resources other than petroleum naphtha, especially those that are cheaper and more abundant. Examples of such hydrocarbon resources include natural gas, coal, and heavy oil found in abundant supplies at locations far from the ethylene market. Currently, there are two ways to convert remote hydrocarbon resources to ethylene, where the ethylene is produced in an industrialized location.

The first method is to convert hydrocarbon resources obtained at remote sites into highly paraffinic feeds by the Fischer-Tropsch process. The method includes converting the hydrocarbon resource to synthesis gas by partial oxidation and converting the synthesis gas to a mixture of hydrocarbons by a Fischer-Tropsch process. The hydrocarbon fraction from the Fischer-Tropsch process can be used as a feed to the naphtha cracking process to produce ethylene. As an example, European Patent Application No. 161705 discloses that a fraction of the product of a Fischer-Tropsch synthesis process can be used as a hydrocarbon feed in a naphtha cracking process. EP 161705 discloses the use of a C _19- cut from a Fischer-Tropsch process consisting essentially of linear paraffin as the feed for the naphtha cracking process. EP 161705 further discloses that the use of this feed increases the selectivity for lower olefins compared to the naphtha fraction of crude oil.

  Highly paraffinic Fischer-Tropsch naphtha treated with hydrogen, including hydroprocessing, hydrocracking, and hydroisomerization, is typically used to increase the selectivity of naphtha cracking processes. The To produce ethylene, the highly paraffinic Fischer-Tropsch naphtha is typically transported from a synthesized site to an industrialized site and converted to ethylene in a naphtha cracker.

  As an example, August 18-22, 2002, Boston, Massachusetts, ACS 2002 National Conference, July 2002 ACS Preprint, Luis P. et al. “The performance of a SASOL SPD naphtha as a steam cracking feed” by Danquart et al. And US Pat. No. 5,371,308 describe examples of this method. U.S. Pat. No. 5,371,308 teaches a method for cracking a hydrocarbon feed containing a hydrotreated synthetic oil fraction from a hydrocarbon feed containing a hydrotreated synthetic oil fraction to produce a lower olefin. ing. The hydrotreated synthetic oil fraction is derived from a synthesis process such as the Fischer-Tropsch synthesis process and then processed in a manner in which hydrogen is present.

  A second method for converting remote hydrocarbon resources to ethylene involves the production of methanol. The method includes converting hydrocarbon resources obtained at remote sites into synthesis gas by partial oxidation, and converting the synthesis gas to methanol in a methanol synthesis facility. The methanol is typically transported to an industrialized site and converted to ethylene by a methanol to olefin process. The methanol to olefin process uses a molecular sieve to dehydrate the methanol and convert it to a mixture of ethylene, propylene and other olefins.

  The use of a process involving Fischer-Tropsch naphtha for producing ethylene has advantages over the methanol process. These advantages include the ability to use existing naphtha crackers where existing methods including Fischer-Tropsch naphtha exist. Also, the highly paraffinic naphtha produced by this process consists of a mixture of normal paraffins and isoparaffins that are low in cyclic compounds (aromatic hydrocarbons and naphthenes). This highly paraffinic naphtha provides higher yields of ethylene and lower coking rates than typical petroleum naphtha.

  However, there are some disadvantages to methods involving the use of Fischer-Tropsch naphtha. The disadvantages include the high cost associated with converting methane to highly paraffinic naphtha. One element of this high price is the hydrogen typically required to hydrotreat the Fischer-Tropsch product to provide a highly paraffinic naphtha. Further, the ethylene cracking process includes a high temperature endothermic reaction that dehydrocrackes the naphtha into smaller pieces. This high temperature endothermic reaction requires the use of significant amounts of expensive fuel.

  Methods involving methanol synthesis may require fewer steps, but are generally less economical in producing methanol from natural gas. Furthermore, when transporting methanol, it must be remembered that roughly 50% by weight of methanol is converted to water during the methanol to olefin process. Therefore, roughly twice the amount of methanol must be transported compared to paraffinic naphtha. In addition, because methanol is toxic, it is typically transported in small specialized tankers at a higher price than that required for paraffinic naphtha. Finally, this method requires the construction of a new facility for the methanol to olefin process.

  There is a need for an economical and efficient method for converting inexpensive hydrocarbon resources (such as methane or coal from remote sites) to ethylene in an industrialized location. It is desirable that these methods have some advantages. The initial conversion from hydrocarbon resources to naphtha cracker feed should be economical. It is desirable that the feed provides a high yield of ethylene and therefore initially the amount of feed required is relatively small. It is desirable that the operation cost of the naphtha decomposition process is low. The method should generally be compatible with existing equipment including, for example, ships, tanks, pumps, naphtha crackers, and the like.

  The present invention relates to a technique for producing a lower olefin from a high-purity olefinic naphtha. In one aspect, the present invention relates to a method for producing a lower olefin. The method includes converting at least a portion of the hydrocarbon resource to synthesis gas and converting at least a portion of the synthesis gas to olefinic naphtha by a Fischer-Tropsch process. At least a portion of the olefinic naphtha is converted into a product stream containing lower olefins in a naphtha cracker and at least a portion of the lower olefins are recovered from the product stream of the naphtha cracker.

  In another aspect, the present invention relates to a method for producing ethylene. The method includes converting at least a portion of the hydrocarbon resource to synthesis gas and converting at least a portion of the synthesis gas to a hydrocarbon stream in a Fischer-Tropsch individual apparatus. An olefinic naphtha containing 20 to 75 wt% non-olefin containing 25 to 80 wt% olefin and more than 75 wt% paraffin is isolated from the hydrocarbon stream. Purifying the olefinic naphtha in the presence of a metal oxide to provide a purified olefinic naphtha having a total acid number less than 1.5, wherein at least a portion of the purified olefinic naphtha is freed of ethylene in a naphtha cracker. Convert to product stream containing. At least a portion of the ethylene is recovered from the product stream of the naphtha cracker.

  In a further aspect, the present invention is a first site and a second site far apart from each other, the first site forming the olefinic Fischer-Tropsch naphtha used at the second site and the second site forming ethylene. The present invention relates to a method for producing ethylene including a site. The process receives an olefinic Fischer-Tropsch naphtha at a second site, converts the olefinic naphtha into a product stream containing ethylene in a naphtha cracker, and isolates ethylene from the product stream of the naphtha cracker Including doing. In this method, the olefinic Fischer-Tropsch naphtha converts hydrocarbon resources into synthesis gas, and subjecting the synthesis gas to Fischer-Tropsch synthesis to form a hydrocarbonaceous product, the hydrocarbonaceous product From an olefinic Fischer-Tropsch naphtha.

In yet another aspect, the present invention relates to an olefinic naphtha. The olefinic naphtha is (a) an olefin in an amount of 10 to 80% by weight, (b) a non-olefin in an amount of 20 to 90% by weight containing more than 50% by weight of paraffin, and (c) less than 10 ppm by weight. Amount of sulfur, (d) less than 10 ppm by weight of nitrogen, (e) less than 10% by weight of aromatic hydrocarbons, (f) total acid number lower than 1.5, and (g) C ₅ A boiling range of ˜400 ° F.

The present invention also includes (a) an olefin in an amount of 25 to 80% by weight consisting of greater than 65% by weight linear primary olefin, and (b) greater than 75% by weight paraffin, A non-olefin in an amount of 20 to 75% by weight having an i / n ratio lower than 1, (c) an amount of sulfur less than 2 ppm by weight, (d) an amount of nitrogen less than 2 ppm by weight, (e) 2 wt. % lesser amounts of aromatic hydrocarbons lower than (f) 1.5 total acid number, and also relates to olefinic naphtha containing, boiling range _{(g) C 5 ~400 ° F} .

  In another aspect, the present invention relates to a method for producing an olefinic naphtha. The method includes converting at least a portion of the hydrocarbon resource to synthesis gas and converting at least a portion of the synthesis gas to a hydrocarbon stream in a Fischer-Tropsch individual apparatus. An olefinic naphtha containing 20 to 90 wt% non-olefin containing 10 to 80 wt% olefin and more than 50 wt% paraffin is isolated from the hydrocarbon stream. The olefinic naphtha is purified by contacting the olefinic naphtha with a metal oxide at an elevated temperature, and a purified olefinic naphtha having a total acid number lower than 1.5 is isolated.

  In yet another aspect, the present invention relates to a mixed naphtha. The mixed naphtha comprises (a) an olefinic naphtha comprising (a) an olefin in an amount of 10 to 80% by weight and a non-olefin in an amount of 20 to 90% by weight containing more than 50% by weight of paraffin, and (b) hydrogen. A treated Fischer-Tropsch derived naphtha, a hydrocracked Fischer-Tropsch derived naphtha, a hydrotreated petroleum derived naphtha, a hydrocracked petroleum derived naphtha, and a naphtha selected from the group thereof. The mixed naphtha contains less than 10 ppm sulfur and has an acid number less than 1.5.

  In a further aspect, the present invention relates to a method for producing a mixed naphtha. The method includes converting at least a portion of a hydrocarbon resource to synthesis gas and converting at least a portion of the synthesis gas to a hydrocarbon stream in a Fischer-Tropsch reactor. Isolate an olefinic naphtha containing 20-90 wt% non-olefin containing 10-80 wt% olefin and greater than 50 wt% paraffin. The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. And provide mixed naphtha. The mixed naphtha contains less than 10 ppm sulfur and has an acid number less than 1.5.

  In yet a further aspect, the present invention relates to a method for producing a mixed naphtha. The method includes providing an olefinic naphtha comprising 10 to 80 wt% olefin and 20 to 90 wt% non-olefin containing more than 50 wt% paraffin. The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. And provide mixed naphtha. The mixed naphtha contains less than 10 ppm sulfur and has an acid number less than 1.5.

Describes how to convert natural gas to ethylene along with other sub-manufacturing products.

Detailed Description of the Invention
The present invention relates to an olefinic naphtha and a method for producing a lower olefin from the olefinic naphtha.

Definitions The following terms are used throughout the specification and have the following meanings unless otherwise indicated.

The term “naphtha” means a hydrocarbonaceous mixture containing a compound that boils between C ₅ and 400 ° F. C ₅ analysis is performed by gas chromatography, the temperature of 400 ° F refers to the 95% boiling point as measured by ASTM D-2887. Of the hydrocarbon electrolyte mixture, preferably at least 65%, most preferably at least 85% boils between C ₅ and 400 ° F.

  The term “paraffin” means a saturated straight or branched chain hydrocarbon (ie, alkane).

  The term “olefin” means an unsaturated linear or branched hydrocarbon (ie, alkene) having at least one double bond.

  The term “olefinic naphtha” means a naphtha containing 10 to 80% by weight of olefins and 20 to 90% by weight of non-olefins mainly containing paraffins. Preferably, the olefinic naphtha contains 25-80 wt% or more olefin, more preferably 50-80 wt% olefin. Preferably, the non-olefin of the olefinic naphtha contains more than 50 wt.% Paraffin, more preferably more than 75 wt.% Paraffin, and even more preferably more than 90 wt. Based on). Preferably, the olefinic naphtha also contains less than 10 ppm sulfur and less than 10 ppm nitrogen, more preferably both sulfur and nitrogen are less than 5 ppm, more preferably less than 2 ppm and even more preferably less than 1 ppm. Preferably, the olefinic naphtha contains less than 10 wt% aromatic hydrocarbons, more preferably less than 5 wt% aromatic hydrocarbons, and even more preferably less than 2 wt% aromatic hydrocarbons. Olefin and aromatic hydrocarbons are preferably measured by SCFC (Supercritical Fluid Chromatography).

  The term “lower olefin” means an olefin having 2 to 4 carbons. Preferably lower olefins refer to ethylene and propylene, more preferably ethylene.

  The term “linear primary olefin” means a linear 1-alkene commonly known as an alpha olefin.

  The term “total acid number” or “acid number” is a measure of acidity. It is determined by the milligrams of potassium hydroxide (mg KOH / g) required to neutralize the acid present in one gram of sample measured, as measured by ASTM D 664 or a suitable equivalent. The olefinic naphtha used in the process of the present invention preferably has a total acid number below 1.5 mg KOH / g, more preferably below 0.5 mg KOH / g.

  The term “oxygenate” means a hydrocarbon containing oxygen, ie an oxygenated hydrocarbon. Oxygenates include alcohols, ethers, carboxylic acids, esters, ketones, aldehydes, and the like.

  The term “i / n ratio” means the isoparaffin / normal paraffin weight ratio. It is the ratio of the total number of isoparaffins (ie, branched chains) to the total number of normal paraffins (ie, straight chains) in a sample.

  The term “derived from the Fischer-Tropsch process” or “Fischer-Tropsch process” is used to describe whether the product, fraction, or feed is derived from the Fischer-Tropsch process or is produced at some stage by the Fischer-Tropsch process. Means that

  The term “petroleum-derived” or “petroleum-derived” means that the product, fraction, or feed comes from residual fuel that is an overhead vapor stream and non-evaporable residue from the distillation of crude oil. . The source of petroleum derivatives can come from gas field condensates.

The term “hydrotreated Fischer-Tropsch derived naphtha” means a naphtha derived by hydrotreating a C ₅ -400 ° F. containing Fischer-Tropsch product.

  The term “hydrocracking Fischer-Tropsch derived naphtha” means a naphtha derived by hydrocracking a 400 ° F. + containing Fischer-Tropsch product.

  The term “hydrocracked petroleum-derived naphtha” means a naphtha derived by hydrocracking a 400 ° F + containing petroleum-derived product.

The term “hydrotreated petroleum-derived naphtha” means naphtha derived from hydrotreating a C ₅ -400 ° F. containing petroleum-derived product.

  The term “high temperature” means a temperature above 20 ° C. In the process of the invention, the high temperature is preferably above 450 ° F. for the purification of olefinic naphtha.

  It has been surprisingly discovered that olefinic naphtha produced by the Fischer-Tropsch process offers some advantages over paraffinic naphtha. For example, the costs associated with producing olefinic naphtha are reduced because hydroprocessing steps and therefore expensive hydrogen are not required to produce olefinic naphtha. Furthermore, when using olefinic naphtha to produce lower olefins such as ethylene, the yield of ethylene is increased because olefins provide higher ethylene yield than paraffin. Therefore, the amount of feed to the naphtha cracker to produce the desired amount of ethylene is less using olefin feed compared to paraffin feed. Furthermore, operating costs for naphtha crackers are reduced because less heat is required to convert olefins to ethylene than for the corresponding paraffins. Furthermore, when producing olefinic naphtha and lower olefins from the olefinic naphtha, existing facilities such as ships, tanks, pumps, naphtha crackers and the like can be used.

  Accordingly, the present invention relates to olefinic naphtha. The olefinic naphtha of the present invention is produced by the Fischer-Tropsch process.

In the Fischer-Tropsch synthesis process, liquid and gaseous hydrocarbons are formed by contacting a synthesis gas containing a mixture of H ₂ and CO with a Fischer-Tropsch catalyst under appropriate temperature and pressure reaction conditions. Fischer-Tropsch reactions are typically about 300-700 ° F. (149-371 ° C.), preferably about 400-550 ° F. (204-228 ° C.), about 10-600 psia (0.7-41 bar). ), Preferably 30 to 300 psia (2 to 21 bar) and a catalyst space velocity of about 100 to 10,000 cc / g / hr, preferably 300 to 3,000 cc / g / hr.

The product is mostly in the C _{5 to} C ₁₀₀₊ range, but can vary from C ₁ to C ₂₀₀₊ . The reaction can be carried out in various types of reactors, for example fixed bed reactors containing one or more catalyst beds, slurry reactors, fluidized bed reactors, or combinations of different types of reactors. Such reaction methods and reactors are well known and documented in the literature. The preferred slurry Fischer-Tropsch process for the practice of the present invention utilizes the excellent heat (and mass) transfer characteristics for strongly exothermic synthesis reactions and produces relatively high molecular weight paraffinic hydrocarbons when using cobalt catalysts. I can do it. In the slurry process, the synthesis gas containing a mixture of H ₂ and CO is a granular Fischer-Tropsch hydrocarbon synthesis catalyst dispersed and suspended in a slurry liquid containing the hydrocarbon product of the synthesis reaction that is liquid under the reaction conditions. It is bubbled through the slurry in the containing reactor as the third phase. The molar ratio of hydrogen to carbon monoxide can vary widely from about 0.5 to 4, but more typically within the range of about 0.7 to 2.75, preferably about 0.7 to 2.5. It is. A particularly preferred Fischer-Tropsch process is taught in EP0609079.

Suitable Fischer-Tropsch catalysts include one or more Group VIII catalytic metals such as Fe, Ni, Co, Ru, and Re. In addition, suitable catalysts can contain promoters. Thus, the preferred Fischer-Tropsch catalyst is an effective amount of cobalt and Re, Ru, Pt, Fe, Ni, Th, Th on a suitable inorganic support material, preferably one containing one or more refractory metal oxides. One or more of Zr, Hf, U, Mg and La are included. Generally, the amount of cobalt present in the catalyst is from about 1 to about 50 percent of the total catalyst composition. The _{catalyst, ThO 2, La 2 O 3} , MgO, and basic oxide promoters such as TiO _2, promoters such as ZrO _2, noble metals (Pt, Pd, Ru, Rh , Os, Ir), Money metals (Cu, Ag, Au) and other transition metals such as Fe, Mn, Ni, and Re can also be included. Support materials including alumina, silica, magnesia, and titania or mixtures thereof can also be used. A preferred support for the cobalt-containing catalyst comprises titania. Useful catalysts and their preparation are known and useful for illustration, but non-limiting examples can be found in, for example, US Pat. No. 4,568,663.

Products from a Fischer-Tropsch reaction conducted in a suspension bed reactor generally include light and waxy reaction products. Light reaction products (ie, condensate fractions) are below about 700 ° F. (eg, from tail gas to middle distillate), mostly in the C _{5 to} C ₂₀ range, up to about C ₃₀ Contains hydrocarbons that boil while decreasing. Waxy reaction product (i.e.,含蝋oil) is above about 600 ° F (e.g., from vacuum gas oil to heavy paraffins), with mostly C ₂₀₊ range, up to C ₁₀ are diminishing the amount Contains boiling hydrocarbons. Both the light reaction product and the waxy product are substantially paraffinic. Waxy products generally contain more than 70% normal paraffins and often more than 80% normal paraffins. Light reaction products include paraffinic products along with a significant proportion of alcohols and olefins. In some cases, the light reaction product may contain as much as 50% or even more alcohol and olefin.

The olefinic naphtha of the present invention can be isolated from the product of the Fischer-Tropsch process by distillation. Olefinic naphtha of the present invention boils between _C 5 _~400 ° F.

  In the method of the present invention, the olefinic naphtha can be purified. Olefinic naphtha from Fischer-Tropsch facilities frequently contains impurities that should be removed without olefin saturation. Examples of these impurities include acids and heavy metals. The acids present in Fischer-Tropsch naphtha are corrosive and will rapidly attack the metal surfaces of ships, tanks, pumps, and naphtha crackers. As the acid attacks the metal, it will be entrained in the naphtha and will increase flame tube fouling in, for example, a down-flow processor including a naphtha cracker. Further, the metal can be incorporated into the naphtha by direct reaction of the acid with a typical Fischer-Tropsch catalyst, such as iron. Therefore, it would be necessary to remove the acid and dissolved metal present in the olefinic naphtha by a method that can remove the olefin without saturating.

  Alcohol and other oxygenates may also be present in the olefinic naphtha from the Fischer-Tropsch facility. While alcohol and other oxygenates can be processed in a naphtha cracker, it is desirable to remove them as well as dissolved metals and acids.

  When processing conventional petroleum, typically the crude oil should have a total acid number lower than 0.5 mg KOH / g to avoid corrosion problems. In addition, the distillate fraction typically has an acid number lower than 1.5 mg KOH / g. 1998, Houston, Texas, International Association for Anticorrosion Technology (NACE International), Richard A. See White, “Material Selection for Petroleum Refining and Oil Collection Facilities,” pages 6-9.

  Thus, the purification method of the present invention for olefinic naphtha is preferably less than 1.5 mg KOH / g, more preferably less than 1.0 mg KOH / g, without appreciably saturating the olefins contained therein. Even more preferably, an olefinic naphtha having a total acid number lower than 0.5 mg KOH / g can be provided. Olefinic naphtha isolated directly from the Fischer-Tropsch process can have an acceptable total acid number. However, if the isolated olefinic naphtha does not have an acceptable total acid number, it may be necessary to purify it as described herein.

  In the prior art for producing highly paraffinic naphtha, impurities including acids, alcohols and other oxygenates are removed by hydrotreating techniques such as hydrotreating, hydrocracking, hydroisomerization and the like. However, these processes also simultaneously convert the desired olefin to a relatively less desirable paraffin.

  According to the present invention, acids and dissolved metals in Fischer-Tropsch naphtha are removed by contacting the naphtha with a metal oxide catalyst at an elevated temperature. When the naphtha is contacted with the metal oxide at a high temperature, the acid is converted to paraffin and olefin by a decarboxylation reaction. In addition, the alcohol is converted to further olefins by dehydration, and other oxygenates (including ethers, esters, and aldehydes found in relatively small amounts) are converted to hydrocarbons. In this naphtha purification process, expensive hydrogen is not required, but can be used if desired (to improve catalyst / naphtha contact or for thermal management). The oxygen in the naphtha is converted to water and carbon dioxide, which can be easily separated from the olefinic naphtha product.

  If dissolved metals are present in the naphtha, they will be simultaneously removed and deposited on the metal oxide catalyst. Typically, the metal oxide catalyst used in the purification process according to the present invention will exhibit a low deactivation rate, but eventually the catalyst will need to be regenerated or replaced. The regeneration of the catalyst can be accomplished by stripping with a hot gas (hydrogen or other gas) or by burning the catalyst while it is in contact with an oxygen-containing gas at an elevated temperature. Regeneration by combustion is preferred.

  Preferably, the purification according to the invention contains metal oxides at 450-800 ° F., less than 1000 psig, and without adding gaseous components under conditions of 0.25-10 LHSV (liquid hourly space velocity) This can be done by passing an olefinic naphtha through a refining unit. As an example, the purification method can be performed by passing an olefinic naphtha downward through a refined individual apparatus containing a metal oxide at a high temperature.

  Preferably, the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay and mixtures thereof. Since it is believed that the terminal olefin provides the highest yield of ethylene, an oxide that is effective in oxygenate dehydration but does not promote isomerization of the olefin from the terminal position to the internal position or to the branched olefin. It is preferable to select. Based on this, the preferred metal oxide is alumina. Additional components can be added to the metal oxide to promote dehydration or delay olefin isomerization. Examples of such further components are basic elements such as Group I or II elements of the periodic table. These basic components can also delay catalyst fouling. Usually these components are incorporated into the finished catalyst in the form of oxides.

  In order to achieve the desired total acid number, the stringency of the purification method can be varied as required. Typically, the stringency of the process can be varied by adjusting the temperature and LHSV (Liquid Hourly Space Velocity). Thus, more stringent purification can be achieved by carrying out the purification process at higher temperatures, and more oxygenates are removed under these more stringent purification conditions, thus olefins having a lower total acid number. A series naphtha will be provided.

  The purification method of the present invention preferably does not saturate the contained olefin, preferably lower than 1.5 mg KOH / g, more preferably lower than 1.0 mg KOH / g, even more preferably lower than 0.5 mg KOH / g. An olefinic naphtha having a low total acid number is provided. The purification process of the present invention preferably removes more than 80 weight percent oxygenates in the olefinic naphtha.

  The olefinic naphtha according to the present invention is a naphtha containing 10 to 80% by weight of olefin and 20 to 90% by weight of non-olefin mainly containing paraffin. Preferably, the olefinic naphtha contains 25-80 wt% or more olefin, more preferably 50-80 wt% olefin. The olefin of the olefinic naphtha is mainly a linear primary olefin. Preferably, the olefin is greater than 50 wt% linear primary olefin, more preferably greater than 65 wt% linear primary olefin, even more preferably greater than 80 wt% linear primary olefin. including.

  The non-olefinic component of the olefinic naphtha is mainly paraffinic. Preferably the non-olefin comprises greater than 50 wt% paraffin (measured based on non-olefinic components), more preferably greater than 75 wt% paraffin, even more preferably greater than 90 wt% paraffin. The non-olefinic paraffin of the naphtha is mainly n-paraffin. Preferably the paraffin has an i / n ratio below 1.0, more preferably below 0.5.

  Furthermore, preferably the olefinic naphtha also contains less than 10 ppm sulfur and less than 10 ppm nitrogen, more preferably less than 5 ppm, more preferably less than 2 ppm, and even more preferably less than 1 ppm. Furthermore, the olefinic naphtha preferably contains less than 10% by weight aromatic hydrocarbons, more preferably less than 5% by weight aromatic hydrocarbons, and even more preferably less than 2% by weight aromatic hydrocarbons. Olefin and aromatic hydrocarbons are preferably measured by SCFC (supercritical fluid chromatography).

  The olefinic naphtha according to the present invention can also be mixed to provide a mixed naphtha. This mixed naphtha can be used for any purpose for which naphtha is used. These objectives include processes for the production of ethylene, including both traditional processes and the process of the present invention. The mixed naphtha is from the group consisting of the above-mentioned olefinic naphtha and hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum naphtha, and mixtures thereof. Contains the selected naphtha. The mixed olefinic naphtha according to the present invention is obtained by a method comprising mixing an appropriate amount of an olefinic naphtha described herein with another naphtha selected from the group defined above to provide a mixed naphtha. Manufactured. The olefinic naphtha can be produced by the method described herein.

  The mixed naphtha according to the present invention contains less than 10 ppm sulfur and has an acid number lower than 1.5 mg KOH / g. Preferably, the mixed naphtha has an acid number lower than 0.5 mg KOH / g. Also preferably, the mixed naphtha contains less than 10 ppm nitrogen, more preferably both sulfur and nitrogen are less than 5 ppm, more preferably less than 2 ppm and even more preferably less than 1 ppm. Further, the mixed naphtha preferably contains less than 10 wt% aromatic hydrocarbons, more preferably less than 5 wt% aromatic hydrocarbons, and even more preferably less than 2 wt% aromatic hydrocarbons.

  The mixed naphtha according to the present invention may contain varying amounts of olefinic naphtha relative to the other naphthas defined above. Preferably, the mixed naphtha comprises 10 to 90 wt% olefinic naphtha and 90 to 10 wt% other naphtha as defined above. More preferably, the mixed naphtha comprises 30-70 wt% olefinic naphtha and 70-30 wt% other naphtha.

  The olefinic naphtha of the present invention provides an excellent feed for naphtha crackers for the production of lower olefins. The process for producing lower olefins according to the present invention comprises converting at least a portion of the olefinic naphtha described above into a product stream containing lower olefins in a naphtha cracker, the lower olefins being recovered from this product stream.

  Hydrolysis of hydrocarbons is a major route for the industrial production of ethylene. Typical conditions for carrying out the pyrolysis to produce ethylene were April 16, 2001, Kirk-Othmer Encyclopedia of Chemical Technology, K .; M.M. Sundaram et al., “Ethylene”, which is incorporated herein by reference in its entirety. The pyrolysis reaction proceeds in the pyrolysis coil of the radiant portion of the furnace. Coke is also formed during pyrolysis, so water vapor is added as a diluent to the feed. The steam minimizes side reactions that form coke and improves the selectivity to produce the desired olefin by lowering the hydrocarbon partial pressure. The temperature of the mixture of hydrocarbon and water vapor entering the radiation chamber (known as the crossover temperature) is 500-700 ° C. Depending on residence time and required feed stringency, the coil exit temperature is typically maintained at 775-950 ° C.

The combination of low residence time and low partial pressure results in high selectivity for olefins at constant feed conversion. In the 1960s the residence time was 0.5 to 0.8 seconds, but in the late 1980s the residence time was typically 0.1 to 0.15 seconds. Typical pyrolysis heater properties are listed in the table below.

The cracking reaction uses 1.6 to 2.8 MJ / kg (700 to 1200 BTU / lb) for the converted hydrocarbons using heat supplied by burning fuel gas and / or fuel oil in the sidewall or floor burner. Endothermic. Side wall burners usually provide a uniform heat distribution, but each burner has a limited capacity (0.1-1 MW), so 40-200 burners are required in a single furnace. The use of modern floor burners, also known as iori burners, provides a uniform heat flow distribution for coils as high as 10 m, which are widely used in relatively new designs. Since the capacity of these burners varies significantly (1-10 MW), only a few burners are required. The choice of burner depends on the type of fuel (gas and / or liquid), the source of combustion air (ambient air, preheated air, or gas turbine exhaust) and the required NO _x level. The reaction mixture emerging from the furnace is rapidly cooled with a quench cooler.

Use of the olefinic naphtha as a feed to the naphtha cracker increases the yield of ethylene compared to paraffinic naphtha. Improvements in ethylene yield during naphtha cracking can be understood by examining the chemistry of naphtha cracking. For typical C ₆ paraffins, the decomposition reaction (without dehydrogenation) is as follows.
C ₆ H ₁₄ → 2C ₂ H ₄ + C ₂ H ₆
Thus, 1 mole of hexane yields 2 moles of ethylene and 1 mole of ethane.

The reaction for the corresponding C ₆ olefins are as follows.
C ₆ H ₁₂ → 3C ₂ H ₄
Since olefins are deficient in hydrogen compared to paraffins, less low-value ethane is produced, and the yield of desired ethylene can be increased by 50%. However, under industrial conditions, some of the starting hexane will be dehydrogenated to form hexene and hydrogen, so the actual ethylene yield will increase beyond what would be expected without dehydrogenation. I will. Nevertheless, when using olefinic feeds, the ethylene yield increases beyond that observed with the corresponding paraffin. Thus, the cracking reaction of the present invention is more efficient because it uses the olefinic naphtha feed described above.

  Furthermore, the cracking reaction of the present invention using an olefinic naphtha feed is more economical. The conversion of paraffin (ie, hexane) to ethylene and the conversion of olefin (ie, hexene) to ethylene are endothermic and require high temperatures, but the endothermic dehydrogenation reaction does not occur to the same extent, so paraffin conversion The olefin conversion is less endothermic. Thus, energy consumption during the conversion of olefinic naphtha to ethylene is lower than expected for the corresponding paraffin. Due to this lower energy consumption, the operating costs of the steam cracker are reduced.

  Note that current feedstocks used in naphtha crackers do not contain significant amounts of olefins because they are typically derived from petroleum that lacks these compounds. It is.

Treatment of olefinic feedstock in the naphtha cracker can lead to an increase in the degree of furnace tube coking. However, if this happens, any one or combination of the following measures can be taken to suppress this problem. These measures include increasing the frequency of the decoking operation, increasing the ratio of H ₂ O / hydrocarbon feed, adding sulfur or a sulfur-containing stream to the feed, and tin, chromium, Application of the reactor with a coke passivating agent such as aluminum, germanium and combinations thereof is included.

  In the method for producing a lower olefin of the present invention, at least a part of the hydrocarbon resources is converted into synthesis gas. The hydrocarbon resource can be selected from the group consisting of coal, natural gas, petroleum, and combinations thereof. At least a portion of the synthesis gas is converted to olefinic naphtha by the Fischer-Tropsch process as described above. The olefinic naphtha can be isolated from the Fischer-Tropsch product stream and purified as described above by contacting with the metal oxide at an elevated temperature if desired. At least a portion of the olefinic naphtha is converted into a product stream comprising lower olefins in a naphtha cracker and at least a portion of the lower olefins are recovered from the product stream. Preferably these lower olefins comprise ethylene.

A preferred embodiment of the present invention is illustrated in FIG. At a location remote from the ethylene production facility, methane (10) is mixed with oxygen and water vapor (both not shown) and reacted in a syngas generator (20) to form a syngas stream (30). . The synthesis gas is reacted in a slurry phase Fischer-Tropsch individual apparatus (40) to produce a liquid phase product (50) and a vapor phase product (60). Separating the vapor phase product to form a distillate range material (90) containing C ₁₀ and its larger hydrocarbonaceous compounds. Also produced by this separation is an olefinic naphtha (80) containing a hydrocarbon compound of C _{5 to} 400 ° F. The olefinic naphtha is passed down through the refining unit (100) at 680 ° F., 50 psig, and 5 LHSV (liquid hourly space velocity) without the addition of gaseous components. The refined individual apparatus contains alumina. The refining unit removes more than 80% oxygenated compounds, increases the olefin content, and decreases the acidity of the olefinic naphtha. Purified olefinic naphtha is produced (120) and transported to an ethylene production site (140) where it is cracked in a naphtha cracker (160) to produce an ethylene-containing stream (170). Sellable ethylene is recovered from the ethylene-containing stream by a process not shown.

  Meanwhile, the liquid phase product (50) from the Fischer-Tropsch facility containing 400 ° F + material is mixed with the distillate range material (90) and the mixture is treated with a hydrogenation facility (110) to produce the product. The goods are converted into sellable products: diesel fuel, jet fuel, and / or lube base stock (130). The hydrogenation equipment consists of hydrocracking, hydrotreating and / or hydroisomerization processes. These sellable products are transported (150) to the market (180). Also, paraffinic naphtha (not shown) produced with other selling products in the hydrogenation facility (110) can be mixed and transported with purified olefinic naphtha (120).

  The selective purification of olefinic naphtha can be done before or after transport (as indicated above) and before conversion in the steam cracker, or at both locations. .

  The invention is further illustrated by the following non-limiting illustrative examples.

Fischer-Tropsch olefinic naphtha Two olefinic naphthas produced by the Fischer-Tropsch process were obtained. The first (feedstock A) was produced using an iron catalyst. The second (feedstock B) was prepared using a cobalt catalyst. The Fischer-Tropsch process used to produce both feeds was operated in the slurry phase. The properties of the two feeds are shown in Table 4 below.

  Feedstock A contains a significant amount of dissolved iron and is also acidic. It has a fairly bad degree of corrosion.

  For the purposes of the present invention, feedstock B is preferred. It has less oxygenate, lower acid content and less corrosivity. Therefore, it is preferable to produce an olefinic naphtha for producing ethylene from a cobalt catalyst rather than an iron catalyst. The degree of impurities that the naphtha from the cobalt catalyst may have is sufficiently low so that it can be used without further treatment or purification as described above.

  A modified version of ASTM D 6550 (Supercritical Fluid Chromatography, a standard test method for measuring gasoline olefin content by SFC) was used to determine the type of groups in the feed and products. The correction method can determine the total amount of saturated hydrocarbons, aromatic hydrocarbons, oxygenates and olefins by creating a three-point calibration standard. Calibration standard solutions were prepared using the following compounds: undecane, toluene, n-octanol, and dodecene. An external standard method was used for quantification, but the detection limit is 0.1% by weight for aromatic hydrocarbons and oxygenates and 1.0% by weight for olefins. Please refer to ASTM D6550 for instrument conditions.

  A small aliquot of fuel sample was injected onto a set of two chromatography columns connected in series and transferred using supercritical carbon dioxide as the mobile phase. The first column was packed with high surface area silica particles. The second column contained high surface area silica particles fitted with silver ions.

  Two switching valves were used to route different types of components through the chromatography system to the detector. In forward flow form, saturated hydrocarbons (normal and branched alkanes and cyclic alkanes) pass through both columns to the detector, while olefins are trapped in a silver loaded column and aromatic hydrocarbons and oxygenates are silica column. Retained. Aromatic compounds and oxygenates were then eluted from the silica column to the detector in a back flush mode. Finally, the olefin was backflow displaced from the silver loaded column to the detector.

  A flame ionization detector (FID) was used for quantification. Calibration involves chromatographic analysis of saturated hydrocarbons, aromatic hydrocarbons, oxygenates and olefins compared to standard reference materials containing known mass% total saturated hydrocarbons, aromatic hydrocarbons, oxygenates and olefins with corrected density. Based on the area of the graphic signal. The total of all analysis results was within 3% per 100%, but was standardized to 100% for convenience.

The weight percent of olefin can also be calculated from the bromine number and average molecular weight using the following formula:
Olefin weight% = (bromine number) (average molecular weight) /159.8

  The average molecular weight is preferably measured directly by an appropriate method, but IEC Res. 1996, Volume 35, A.I. G. It can also be estimated by the correlation using API specific gravity and medium boiling point described in “Prediction of molecular weight of petroleum fraction” on pages 985 to 988 of Goossens.

  Preferably, olefins and other components are measured by the modified SFC (supercritical fluid chromatography) method described above.

  According to GCMS (gas chromatography and mass spectrometry) analysis of the feedstock, the saturated hydrocarbons are almost entirely n-paraffins, the oxygenates are mainly primary alcohols, and the olefins are mainly primary linear olefins. (Alpha olefin).

Dehydration Catalyst Commercially available silica-alumina and alumina extrudates were evaluated for dehydration of the olefinic naphtha. The properties of the extrudate are shown in Table 1 below.

Dehydration dehydration experiments on silica-alumina were conducted in a 1 inch downflow reactor without gas addition or liquid recirculation. The catalyst volume was 120 cc.

The Fe-based condensate (feed A) was treated with commercially available silica-alumina. The catalyst was tested at temperatures of 50 psig, and 480 ° F., 580 ° F., and 680 ° F. using 1 LHSV (liquid hourly space velocity) and 3 LHSV space velocity. At 1 LHSV, the total olefin content was 69-70% at all three temperatures, indicating complete conversion of oxygenate. Some degradation was observed with light product yield at 680 ° F., ie 1.2% total C4- and 25% (relative to 20% in the feed) 25% C5-290 ° F. there were. At 3 LHSV and 480 ° F and 580 ° F, the total olefin was 53-55% lower. At 680 ° F and 3LHSV, the total olefin content was 69% and high dehydration activity was obtained. GCMS (gas chromatography and mass spectrometry) data indicated that significant amounts of 1-olefins were converted to internal or branched olefins. The total olefin at 480 ° F was initially 69%, but near the end of the test (running to 960 hours) was 55%. After removal of the catalyst, a significant amount of carbon was observed on the catalyst. Clearly the catalyst was dirty.

  Detailed analytical values of product (D) from the test at 3 LHSV and 680 ° F. are shown in Table 4 below. 84% of the oxygen was removed, the corrosion rate was improved, and iron was reduced below the detection level. The acidity of naphtha was reduced by 25%. The oxygenate was converted to olefin as indicated by an increase in olefin content and a decrease in oxygenate content.

Cold condensate (feedstock B) based on dehydrated Co on alumina was also treated with an alumina catalyst, as in Example 2. A temperature of 480 ° F. to 730 ° F. and LHSV (liquid hourly space velocity) values of 1 to 5 were investigated. At high temperature and 1 LHSV, GCMS (Gas Chromatography and Mass Spectrometry) data showed that double bond isomerization was significant (alpha olefin content decreased). At 5 LHSV and 580 ° F., the dehydration conversion was significantly lower and the majority of the olefins were primary linear olefins. This test was run for 2000 hours and showed no fouling.

  These results show that it is possible to remove all oxygenates from the sample and convert them to olefins. At high oxygenate removal levels, a significant proportion of alpha olefins are isomerized to internal olefins. Although internal olefins are less valuable than alpha olefins as feedstocks for ethylene production, isomerization to internal olefins does not diminish value below standard paraffinic naphtha, and any value as feedstock It is not something that destroys.

  Product (C) was prepared from operation at 5 LHSV and 680 ° F. Detailed properties are shown in Table 1 below. 87% of the oxygen was removed, acidity was reduced by 55%, and trace iron in the sample was removed. The acidity of the final material was below the typical maximum for crude oil, 0.5 mg KOH / g. The oxygenate was converted to olefin, as shown by the increase in olefin content, roughly consistent with the decrease in oxygenate content.

  Metal elements below the ICP (inductively coupled plasma analysis) detection limit in all samples: Al, B, Ba, Ca, Cr, Cu, K, Mg, Mo, Na, Ni, P, Pb, S, Si, Sn , Ti, V.

Oxygenation adsorption Trace levels of oxygenates not removed by high temperature treatment are removed by adsorption using sodium X zeolite (commercially available 13X sieve from EM Science, type 13X, 8-12 mesh beads, part number MX1583T-1). I can do it.

  The adsorption test was conducted in an upflow fixed bed individual apparatus. The adsorption study feed was prepared by treating Co condensate (Feed B) on alumina at 5 LHSV (Liquid Hourly Space Velocity), 680 ° F. and 50 psig. The adsorption study feed had an acid number of 0.47 and an oxygenate content of 0.6% by SFC (supercritical fluid chromatography).

  The treatment conditions for the adsorption were ambient pressure, room temperature, and 0.5 LHSV. The oxygenate content of the treated product was monitored by the SFC method. The adsorption experiment continued to a breakthrough point defined as the appearance of an oxygenate content of 0.1% or more. The breakthrough occurred when the sieve adsorbed an equivalent amount of 14% by weight based on the feed and product oxygenates. The treated product showed 0.05 wt% oxygen, <0.1 ppm nitrogen, and a total acid number of 0.09 by neutron activation analysis.

  The adsorbent can be regenerated by known methods, i.e., oxidative combustion, calcination in an inert atmosphere, water washing, and combinations thereof.

  These results indicate that adsorption treatment can also be used for oxygenate removal. The adsorption treatment can be used as it is or in combination with dehydration.

  Various modifications and variations of the present invention will become apparent to those skilled in the art without departing from the scope and spirit of the invention. From review of the foregoing description, other objects and advantages will become apparent to those skilled in the art.

Aspects of the present invention can be summarized as follows.
(1) a. Olefins in an amount of 10 to 80% by weight,
b. A non-olefin in an amount of 20 to 90% by weight, comprising more than 50% by weight of paraffin;
c. An amount of sulfur less than 10 ppm by weight,
d. Less than 10 ppm nitrogen by weight,
e. Less than 10% by weight of aromatic hydrocarbons,
f. A total acid number lower than 1.5, and g. Boiling range of C ₅ ~400 ° F,
Olefin-based naphtha containing.
(2) The olefinic naphtha according to (1) above, comprising at least 25% by weight olefin, preferably at least 50% by weight olefin.
(3) The olefinic naphtha according to (1) above, wherein the non-olefin contains more than 75% by weight of paraffin, preferably the non-olefin contains more than 90% by weight of paraffin.
(4) The olefin is composed of greater than 50 wt% linear primary olefin, preferably the olefin is composed of greater than 65 wt% linear primary olefin, most preferably the olefin is 80 The olefinic naphtha according to the above (1), which comprises more than% by weight of a linear primary olefin.
(5) The olefinic naphtha according to (1) above, wherein the paraffin has an i / n ratio lower than 1, preferably the paraffin has an i / n ratio lower than 0.5.
(6) The olefinic naphtha according to (1) above, containing less than 2 ppm by weight of sulfur and less than 2 ppm by weight of nitrogen, preferably less than 2% by weight of aromatic hydrocarbons.
(7) The olefinic naphtha according to the above (1) having a total acid value lower than 0.5.
(8) a. An olefinic naphtha comprising an olefin in an amount of 10 to 80% by weight, and a non-olefin in an amount of 20 to 90% by weight, comprising more than 50% by weight of paraffin; and b. A naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof;
Naphtha containing less than 10 ppm sulfur and having an acid number lower than 1.5.
(9) The mixed naphtha according to the above (8) having an acid value lower than 0.5.
(10) Mixed naphtha according to (8) above, containing less than 5 ppm sulfur, preferably less than 2 ppm sulfur.
(11) The mixed naphtha according to (8) above, containing less than 2 ppm nitrogen and less than 2 wt% aromatic hydrocarbons.
(12) The mixed naphtha according to (8) above, wherein the olefinic naphtha contains at least 25% by weight of olefin, preferably the olefinic naphtha contains more than 65% by weight of linear primary olefin.
(13) The mixed naphtha according to (8) above, comprising 10 to 90% by weight of olefinic naphtha and 90 to 10% by weight of naphtha (b).
(14) a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas to olefinic naphtha by the Fischer-Tropsch process;
c. Converting at least a portion of the olefinic naphtha into a product stream comprising lower olefins in a naphtha cracker; and d. A method for producing a lower olefin, comprising recovering at least a part of the lower olefin from a product stream of the naphtha cracker.
(15) The method according to (14) above, wherein the olefinic naphtha has a total acid number lower than 1.5.
(16) The method according to (14), further comprising the step of refining the olefinic naphtha and reducing the solid and acid dissolved therein to provide the purified naphtha.
(17) The method according to (16) above, wherein the purified olefinic naphtha has a total acid number lower than 0.5.
(18) The purification step is performed by contacting the olefinic naphtha with a metal oxide at a high temperature, preferably the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay, and mixtures thereof. The method according to (14) above, which is selected.
(19) The method according to (16), further comprising the step of separating water and carbon dioxide formed in the purification step from the purified naphtha.
(20) The olefinic naphtha comprises 10 to 80 wt% olefin and 20 to 90 wt% non-olefin comprising more than 50 wt% paraffin, preferably the olefinic naphtha is 50 to 80 wt% The process according to (14) above, comprising olefins and 20 to 50% by weight non-olefins comprising more than 50% by weight paraffins.
(21) A linear primary olefinic naphtha containing less than 5 wt% aromatic hydrocarbon, less than 5 ppm sulfur, and less than 5 ppm nitrogen, preferably more than 50 wt% olefin of the olefinic naphtha. The process according to (14) above, comprising an olefin, most preferably the olefin of the olefinic naphtha comprises more than 80% by weight of linear primary olefin.
(22) A naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. The method according to (14), further comprising the step of mixing with naphtha to provide a mixed naphtha and converting at least a portion of the mixed naphtha in the naphtha cracker.
(23) a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas into a hydrocarbon stream in a Fischer-Tropsch individual apparatus;
c. Isolating from the hydrocarbon stream an olefinic naphtha comprising 20 to 75 wt% non-olefin comprising 25 to 80 wt% olefin and greater than 75 wt% paraffin;
d. Refining the olefinic naphtha in the presence of a metal oxide to provide a purified olefinic naphtha having a total acid number lower than 1.5;
e. Converting at least a portion of the purified olefinic naphtha into a product stream comprising ethylene in a naphtha cracker; and f. Recovering at least a portion of the ethylene from the product stream of the naphtha cracker;
A process for producing ethylene comprising:
(24) The olefin of the olefinic naphtha contains more than 50% by weight of linear primary olefin, the non-olefin of the olefinic naphtha contains more than 90% by weight of paraffin, and the paraffin is less than 1. The method according to (23) above, having a ratio.
(25) The process according to (23) above, wherein the purification step reduces the content of solids, acids and alcohols in the olefinic naphtha, preferably the purified olefinic naphtha has a total acid number lower than 0.5. .
(26) Pass through the olefinic naphtha through a refined individual unit containing metal oxides without the addition of gaseous components under conditions of 450-800 ° F. below 1000 psig and 0.25-10 LHSV (liquid hourly space velocity). The method according to (23) above, wherein the purification step is performed.
(27) The method according to (23) above, wherein the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay and mixtures thereof.
(28) Production of ethylene comprising a first site and a second site far apart from each other, the first site forming the olefinic Fischer-Tropsch naphtha used at the second site and the second site forming ethylene A method,
a. At the second site i. Converting hydrocarbon resources into synthesis gas;
ii. Subjecting the synthesis gas to a Fischer-Tropsch synthesis to form a hydrocarbonaceous product;
iii. Isolating olefinic Fischer-Tropsch naphtha from the hydrocarbonaceous product;
Receiving olefinic Fischer-Tropsch naphtha produced by a method comprising:
b. Converting the olefinic naphtha into a product stream comprising ethylene in a naphtha cracker, and c. Isolating ethylene from the product stream of the naphtha cracker,
A process for producing ethylene as described above.
(29) The olefinic naphtha has a total acid number lower than 1.5, and preferably the method of producing the olefinic Fischer-Tropsch naphtha purifies the olefinic naphtha and dissolves the solid and acid dissolved therein. The method according to (28), further comprising the step of providing reduced naphtha.
(30) The process according to (29) above, wherein the purified naphtha has a total acid number lower than 0.5.
(31) The purification is performed by contacting the olefinic naphtha with a metal oxide at a high temperature, and preferably the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay, and mixtures thereof. The method according to (28) above.
(32) The process according to (28) above, wherein the olefinic naphtha comprises 20 to 50% by weight of non-olefin, comprising 50 to 80% by weight of olefin and more than 50% by weight of paraffin.
(33) A naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. The method according to (28), further comprising the step of mixing with the mixture to provide a mixed naphtha and converting the mixed naphtha in the naphtha cracker.
(34) a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas into a hydrocarbon stream in a Fischer-Tropsch individual apparatus;
c. Isolating from the hydrocarbon stream an olefinic naphtha comprising 10 to 80 wt% olefin and 20 to 90 wt% non-olefin comprising more than 50 wt% paraffin;
d. Purifying the olefinic naphtha by contacting the olefinic naphtha with a metal oxide at an elevated temperature; and e. Isolating a purified olefinic naphtha having a total acid number lower than 1.5;
A process for producing an olefinic naphtha.
(35) The metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay and mixtures thereof, preferably the purification step comprises solids, acids and alcohol content in the olefinic naphtha The method according to (34) above, wherein most preferably the isolated and purified naphtha has a total acid number of less than 0.5.
(36) The method according to (34), further comprising a step of separating the water and carbon dioxide formed in the purification step from the purified olefinic naphtha.
(37) Pass through the olefinic naphtha through a refined individual unit containing metal oxide without the addition of gaseous components under conditions of 450-800 ° F and below 1000 psig and 0.25-10 LHSV (liquid hourly space velocity) The method according to (35) above, wherein the purification step is carried out.
(38) a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas into a hydrocarbon stream in a Fischer-Tropsch reactor;
c. Isolating an olefinic naphtha containing 20 to 90 wt% non-olefin containing 10 to 80 wt% olefin and more than 50 wt% paraffin; and d. The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. Providing mixed naphtha,
A process for producing a mixed naphtha, wherein the mixed naphtha contains less than 10 ppm sulfur and has an acid number less than 1.5.
(39) The method according to (38), further comprising a step of purifying the olefinic naphtha to reduce solids and acids dissolved therein.
(40) The method according to (39), wherein the purification step is performed by contacting the olefinic naphtha with a metal oxide at a high temperature.
(41) The method according to (40) above, wherein the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay, and mixtures thereof.
(42) Addition of gaseous components under conditions where the purified naphtha has a total acid number lower than 0.5, preferably lower than 1000 psig at 450-800 ° F. and 0.25-10 LHSV (liquid hourly space velocity) The method according to (39) above, wherein the purification step is carried out by passing the olefinic naphtha through a separate purification apparatus containing a metal oxide.
(43) The process according to (38) above, wherein the mixed naphtha comprises 10 to 90% by weight of olefinic naphtha, preferably the mixed naphtha comprises less than 2 ppm sulfur.
(44) a. Providing an olefinic naphtha comprising 10 to 80 wt% olefin and 20 to 90 wt% non-olefin containing more than 50 wt% paraffin; and b. The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. Providing mixed naphtha,
A process for producing a mixed naphtha, wherein the mixed naphtha contains less than 10 ppm sulfur and has an acid number less than 1.5.
(45) The olefinic naphtha contains 25-80 wt% olefin and 20-75 wt% non-olefin, the non-olefin contains more than 75 wt% paraffin, and the olefin contains more than 50 wt% linear The process according to (44) above, comprising a primary olefin.
(46) The olefinic naphtha contains 50-80 wt% olefin and 20-50 wt% non-olefin, the non-olefin contains more than 75 wt% paraffin, and the olefin contains more than 65 wt% linear The process according to (44) above, comprising a primary olefin.
(47) The mixed naphtha has a total acid number lower than 0.5, preferably the mixed naphtha comprises 10-90 wt% olefinic naphtha, more preferably the mixed naphtha comprises less than 2 ppm sulfur. The method according to (44) above.

Claims (20)

a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas to olefinic naphtha by the Fischer-Tropsch process;
c. Converting at least a portion of the olefinic naphtha into a product stream comprising lower olefins in a naphtha cracker; and d. A method for producing a lower olefin, comprising recovering at least a part of the lower olefin from a product stream of the naphtha cracker.   The process according to claim 1, wherein the olefinic naphtha has a total acid number of less than 1.5.   The process according to claim 1, further comprising the step of purifying the olefinic naphtha to reduce solids and acids dissolved therein to provide a purified naphtha.   The process according to claim 3, wherein the purified olefinic naphtha has a total acid number of less than 0.5.   Performing the purification step by contacting the olefinic naphtha with a metal oxide at an elevated temperature, preferably the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay, and mixtures thereof; The method according to claim 1.   4. The method according to claim 3, further comprising the step of separating the water and carbon dioxide formed in the purification step from the purified naphtha.   The olefinic naphtha comprises 10 to 80 wt% olefin, and 20 to 90 wt% non-olefin, comprising more than 50 wt% paraffin, preferably the olefinic naphtha comprises 50 to 80 wt% olefin, and The process according to claim 1, comprising 20 to 50% by weight of non-olefin, comprising more than 50% by weight of paraffin.   The olefinic naphtha contains less than 5 wt% aromatic hydrocarbon, less than 5 ppm sulfur, and less than 5 ppm nitrogen, preferably the olefinic naphtha contains more than 50 wt% linear primary olefin. The process according to claim 1, wherein most preferably the olefin of the olefinic naphtha comprises more than 80% by weight of linear primary olefin.   The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. Providing a mixed naphtha and converting at least a portion of the mixed naphtha in the naphtha cracker. a. Converting at least some of the hydrocarbon resources into synthesis gas;
b. Converting at least a portion of the synthesis gas into a hydrocarbon stream in a Fischer-Tropsch individual apparatus;
c. Isolating from the hydrocarbon stream an olefinic naphtha comprising 20 to 75 wt% non-olefin comprising 25 to 80 wt% olefin and greater than 75 wt% paraffin;
d. Refining the olefinic naphtha in the presence of a metal oxide to provide a purified olefinic naphtha having a total acid number lower than 1.5;
e. Converting at least a portion of the purified olefinic naphtha into a product stream comprising ethylene in a naphtha cracker; and f. Recovering at least a portion of the ethylene from the product stream of the naphtha cracker;
A process for producing ethylene comprising:   The olefinic naphtha olefin contains more than 50 wt% linear primary olefin, the olefinic naphtha non-olefin contains more than 90 wt% paraffin, and the paraffin has an i / n ratio lower than 1. The method according to claim 10.   11. The process according to claim 10, wherein the purification step reduces the content of solids, acids and alcohols in the olefinic naphtha, preferably the purified olefinic naphtha has a total acid number below 0.5.   By passing the olefinic naphtha through a refined individual unit containing metal oxides without the addition of gaseous components under conditions of 450-800 ° F. below 1000 psig and 0.25-10 LHSV (liquid hourly space velocity). The process according to claim 10, wherein the purification step is carried out.   11. The process according to claim 10, wherein the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay and mixtures thereof. A method for producing ethylene comprising a first site and a second site that are far away from each other, the first site forming the olefinic Fischer-Tropsch naphtha used at the second site, and the second site forming ethylene. And
a. At the second site i. Converting hydrocarbon resources into synthesis gas;
ii. Subjecting the synthesis gas to a Fischer-Tropsch synthesis to form a hydrocarbonaceous product;
iii. Isolating olefinic Fischer-Tropsch naphtha from the hydrocarbonaceous product;
Receiving olefinic Fischer-Tropsch naphtha produced by a method comprising:
b. Converting the olefinic naphtha into a product stream comprising ethylene in a naphtha cracker, and c. Isolating ethylene from the product stream of the naphtha cracker,
A process for producing ethylene as described above.   The olefinic naphtha has a total acid number lower than 1.5, preferably the process for producing the olefinic Fischer-Tropsch naphtha purifies the olefinic naphtha and reduces the solids and acids dissolved therein. 16. The method according to claim 15, further comprising providing a purified naphtha.   The process according to claim 16, wherein the purified naphtha has a total acid number of less than 0.5.   The purification is performed by contacting the olefinic naphtha with a metal oxide at an elevated temperature, preferably the metal oxide is selected from the group consisting of alumina, silica, silica-alumina, zeolite, clay, and mixtures thereof. The method according to Item 15.   The process according to claim 15, wherein the olefinic naphtha comprises 20 to 50 wt% non-olefin, comprising 50 to 80 wt% olefin, and more than 50 wt% paraffin.   The olefinic naphtha is mixed with a naphtha selected from the group consisting of hydrotreated Fischer-Tropsch derived naphtha, hydrocracked Fischer-Tropsch derived naphtha, hydrotreated petroleum derived naphtha, hydrocracked petroleum derived naphtha, and mixtures thereof. 16. The method according to claim 15, further comprising the steps of providing mixed naphtha and converting the mixed naphtha in the naphtha cracker.

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