MX2007007803A - Process for removal of sulfur from components for blending of transportation fuels - Google Patents

Abstract

A process is disclosed for removing highly deletenious non-basic nitrogen compounds upstream from an acid catalyzed thiophene alkylation process using adsorbents capable of adsorbing the non-basic nitrogen compounds.

Description

PROCESS FOR REMOVING SULFUR FROM COMPONENTS FOR THE MIXING OF TRANSPORTATION FUELS Field of the Invention The present invention relates to transportation fuels that are liquid for environmental conditions and are typically derived from natural petroleum. Broadly, it refers to integrated processes for producing products of reduced sulfur content from a feed stream wherein the feed stream comprises limited amounts of sulfur-containing organic compounds as unwanted impurities. More particularly, the invention relates to integrated processes that include the treatment of a refinery stream with a solid adsorbent to remove compounds containing non-basic nitrogen, to the chemical conversion of one or more of the sulfur-containing impurities in knitted products. of higher boiling by alkylation using a contact step with acid catalyst at elevated temperatures. The alkylated sulfur compounds can then be concentrated by distillation and further treated by hydrogenation for the removal of the sulfur. The products can be used directly as transportation fuels and / or blending components to provide fuels that are less aggressive to the environment. REF. : 183048 BACKGROUND OF THE INVENTION It is well known that internal combustion engines have revolutionized transportation after their invention during the last decades of the 19th century. Although others, including Benz and Gottleib Wilhelm Daimler, invented and developed engines that used electric ignition of such fuels Like gasoline, Rudolf CK Diesel invented and built the engine that bears his name and that uses compression to self-ignite the fuel to use low-cost organic fuels. Equally, if not more important, the development of improved spark ignition engines for use in transportation has gone hand in hand with improvements in gasoline fuel compositions. Modern high-performance gasoline engines demand an even more advanced specification of fuel compositions, but cost remains an important consideration. Currently, most transportation fuels are derived from natural oil. In fact, oil so far is the world's leading source of hydrocarbons used as fuel and petrochemical feedstock. Although the compositions of natural petroleum or crude oils vary significantly, all crude contain sulfur compounds and most contain nitrogen compounds that They may also contain oxygen, but the oxygen content of most oils is low. Generally, the concentration of sulfur in the crude is less than about 8 percent, with most of the crude having sulfur concentrations in the range of about 0.05 to about 1.5 percent. The nitrogen concentration is usually less than 0.2 percent, but can be as high as 1.6 percent. Crude oil is rarely used in the form produced in the well, but is converted into petroleum refineries in a wide range of fuels and petrochemical feed streams. Typically transportation fuels are produced by processing and mixing distilled fractions of the crude to meet the particular end-use specifications. Because most of the crude oils currently available in large quantities are high in sulfur, the distilled fractions must be desulfurized to create products that meet performance specifications and / or environmental standards. Organic compounds containing sulfur in fuels continue to be a major source of environmental pollution. During combustion they are converted into sulfur oxides which, in turn, give rise to sulfur oxyacids and also contribute to particle emissions.

Faced with sulfur specifications that are always limiting in transportation fuels, the removal of sulfur from oil and product feed currents will become increasingly important in the years to come. Although legislation on sulfur in diesel fuel in Europe, Japan and the United States has recently reduced the specification to 0.05 percent by weight (maximum), there are indications that future specifications could go well below the current level of 0.05 percent in weight. The legislation on sulfur in gasoline in the United States now limits each refinery to an average of 30 parts per million. In and after 2006 the average specification will be replaced by a ceiling of 80 parts per million maximum. The fluidized catalytic cracking process is one of the main refining processes currently used in the conversion of petroleum into desirable fuels such as gasoline and diesel fuel. In this process, a high molecular weight hydrocarbon feed stream is converted to lower molecular weight products through contact with hot, finely divided solid catalyst particles in a fluidized or dispersed state. Suitable hydrocarbon feed streams typically boil within the range of 205eC to about 6502C, and are usually they contact the catalyst at temperatures on the scale of 450aC to approximately 650aC. Suitable feed streams include various mineral oil fractions such as liquid gas oil, heavy gas oil, wide gas oil, vacuum gas oil, kerosene, decanted petroleum, waste fractions, reduced crude oils and cycle oils which are derived from any of these as well as fractions derived from the processing of shale oils, tar sands and coal liquefaction. The products coming from a fluidized catalytic cracking process are typically based on the boiling point and include light naphtha (boiling between about 102C and about 221aC), heavy naphtha (boiling between about 10aC and about 249aC), kerosene (which boils between about 1802C and about 3002C), light cycle oil (which boils between about 221BC and about 3452C), and heavy cycle oil (which boils at temperatures of more than about 3452C). Not only does the fluidized catalytic cracking process provide a significant portion of the gasoline bank in the United States, but it also provides a large proportion of the sulfur that appears in this bank. Sulfur in the liquid products of this process is in the form of organic sulfur compounds and is an undesirable impurity It turns into sulfur oxides when these products are used as a fuel. These sulfur oxides are objectionable environmental pollutants. In addition, they can deactivate many of the catalysts that have been developed for the catalytic converters that are used in automobiles to catalyze the conversion of harmful engine exhaust emissions to gases that are less objectionable. Accordingly, it is desirable to reduce the sulfur content of the catalytic cracking products to the lowest possible levels. Sulfur-containing impurities from direct-run gasolines, which are prepared by simple distillation of crude oil, are usually very different from those in cracked gasolines. The former contain mainly mercaptans and sulphides, while the latter are rich in thiophene, benzothiophene and derivatives of thiophene and benzothiophene. Low sulfur products are conventionally obtained from the catalytic cracking process by hydrotreating either the feed stream to the process or the process products. Hydrotreating involves the treatment of products from the cracking process with hydrogen in the presence of a catalyst and results in the conversion of the sulfur into sulfur-containing impurities in hydrogen sulfide, which can be separated and become elemental sulfur. Unfortunately, this type of processing is typically very expensive since it requires a source of hydrogen, high pressure process equipment, costly hydrotreating catalysts and a sulfur recovery plant for the conversion of the resulting hydrogen sulfide to elemental sulfur. In addition, the hydrotreating process can result in an unwanted destruction of olefins in the feed stream by converting them into saturated hydrocarbons through hydrogenation. This destruction of olefins by hydrogenation is usually undesirable because it results in the consumption of expensive hydrogen, and also because the olefins are valuable as high octane components of gasoline. As an example, naphtha from a gasoline boiling range of a catalytic cracking process has a relatively high octane number as a result of a high olefin content. The hydrotreating of this material causes a reduction in the content of olefins in addition to the desired desulphurisation, and the octane number of the hydrotreated product is reduced as the degree of desulfurization increases. Conventional hydrodesulphurisation catalysts can be used to remove a large portion of the sulfur from petroleum distillates for the fuel mix for refinery transportation, but they are not efficient for remove sulfur from compounds where the sulfur atom is sterically hindered as in multi-ring aromatic sulfur compounds. This is especially true when the sulfur heteroatom is doubly hindered (for example, 4,6-dimethyldibenzothiophene). Using conventional hydrodesulphurisation catalysts at high temperatures can cause a loss of performance, faster coking of the catalyst and deterioration in product quality (eg color). Using high pressure requires a great waste of capital. Accordingly, there is a need for an economic process for the effective removal of impurities containing sulfur from distilled hydrocarbon liquids. There is also a need for a process that can be used to remove impurities containing sulfur from distilled hydrocarbon liquids, such as products from a fluidized catalytic cracking process, which are highly olefinic and contain both thiophene and benzothiophene compounds as well as unwanted impurities. In order to meet the strictest specifications in the future, each hindered sulfur compound will also have to be removed from feed streams and distilled products. There is an oppressive need for the economic removal of sulfur from refinery fuels for transportation, specifically gasoline components.

The technique is replete with processes that are said to remove sulfur from feed streams and distilled products. The patent of E.U.A. No. 2,448,211, in the name of Phillip D. Caesar, et al., States that thiophene and its derivatives can be alkylated by reaction with olefinic hydrocarbons at a temperature between about 140s and about 4002C in the presence of a catalyst such as a clay. activated natural or a synthetic adsorbent compound of silica and at least one amphoteric metal oxide. Suitable activated clay natural catalysts include clay catalysts on which zinc chloride or phosphoric acid have been precipitated. Suitable amphoteric-silica metal oxide catalysts include combinations of silica with materials such as alumina, zirconia, ceria and thoria. The patent of E.U.A. No. 2,469,823, in the name of Rowland C. Hansford and Phillip D. Caesar, teaches that boron trifluoride can be used to catalyze the alkylation of thiophene and alkylthiophenes with alkylating agents such as olefinic hydrocarbons, alkyl halides, alcohols and mercaptans. In addition, the patent of E.U.A. No. 2,921,081, in the name of Zimmerschied et al., Discloses that acidic solid catalysts can be prepared by combining a zirconium compound selected from the group consisting of zirconium and the zirconium halides with an acid selected from the group consisting of ortho-phosphoric acid, pyrophosphoric acid and triphosphoric acid. The reference Zimmerschied et al. Also notes that thiophene can be alkylated with propylene at a temperature of 227 SC in the presence of this catalyst. The patent of E.U.A. No. 2,563,087 in the name of Jerome A. Vesely notes that thiophene can be removed from aromatic hydrocarbons by selective alkylation of thiophene and removal of the resulting thiophene alkylation by distillation. This selective alkylation is carried out by mixing the aromatic hydrocarbon contaminated with thiophene with an alkylating agent and contacting the mixture with an alkylation catalyst at a carefully controlled temperature in the range of about -20 aC to about 85 SC. It is disclosed that suitable alkylating agents include olefins, mercaptans, mineral acid esters, and alkoxy compounds, such as aliphatic alcohols, ethers and esters of carboxylic acids. It is also disclosed that suitable alkylation catalysts include the following: (1) Friedel-Crafts metal halides, which are most preferably used in anhydrous form; (2) a phosphoric acid, preferably pyrophosphoric acid, or a mixture of this material with sulfuric acid in which the volume ratio of acid sulfuric or phosphoric is less than about 4: 1 and (3) a mixture of a phosphoric acid, such as ortho-phosphoric acid or pyrophosphoric acid, with a siliceous adsorbent, such as kieselguhr or a siliceous clay, which has been calcined to a temperature of about 400a to about 500 BC to form a silica-phosphoric acid combination which is commonly known as a solid phosphoric acid catalyst. The patent of E.U.A. No. 4,775,462 in the name of Tamotsu Imal and Jeffery C. Bricker describes a non-oxidizing method for sweetening a bitter hydrocarbon fraction whereby mercaptans are converted to thioethers which are said to be acceptable in fuels. The method includes contacting a mercaptan-containing hydrocarbon fraction with a catalyst consisting of an acidic inorganic oxide, a sulfuric acid polymer resin, an intercalated compound, a solid acid catalyst, a boron halide dispersed in alumina, a Aluminum halide dispersed in alumina, in the presence of an unsaturated hydrocarbon equal to the molar amount of mercaptans, typically about 0.01 weight percent to about 20 weight percent. Although the product is said to be substantially free of mercaptans, the level of elemental sulfur has not been reduced by this process. The patent of E.U.A. No. 5,171,916 on behalf of Quany N. Le and Michael S. Sarli describe a process for improving a light cycle oil by: (A) alkylating the aromatics containing the cycle oil with an aliphatic hydrocarbon having 14 to 20 carbon atoms and at least an olefinic double bond through the use of a crystalline metallosilicate catalyst; and (B) separating the high boiling alkylation product on the lubricant boiling scale of the non-converted light cycle oil by fractional distillation. It also notes that the unconverted light cycle oil has a reduced content of sulfur and nitrogen, and the high boiling alkylation product is useful as a base material for synthetic alkylated aromatic lubricants. The patent of E.U.A. No. 5,599,441 in the name of Nick A. Collins and Jeffrey C. Trewella discloses a process for removing thiophenic sulfur compounds from a cracked naphtha by: (A) contacting the naphtha with an acid catalyst to alkylate the thiophene compounds using the olefins present in the naphtha as an alkylating agent; (B) removing an effluent stream from the alkylation zone and (C) separating the alkylated thiophenic compounds from the effluent stream of the alkylation zone by fractional distillation. It also notes that additional olefins can be added to the cracked naphtha to provide additional alkylating agent for the process.

More recently, the patent of E.U.A. No. 6,024,865 in the name of Bruce D. Alexander, George A. UHF, Vivek R. Pradhan, William J. Reagan and Roger H. Cayton, describes a product of reduced sulfur content that is produced from a feed stream that it comprises a mixture of hydrocarbons and includes aromatic sulfur-containing compounds as unwanted impurities. The process includes separating the feed stream by fractional distillation at a lower boiling fraction containing the more volatile sulfur-containing aromatic impurities and at least one other higher boiling fraction containing the less volatile sulfur-containing aromatic impurities. Each fraction is then separately subjected to reaction conditions which are effective to convert at least a portion of its content to sulfur-containing aromatic impurities in higher boiling sulfur-containing products by alkylation with an alkylating agent in the presence of a catalyst. acid. Products containing higher boiling sulfur are removed by fractional distillation. It is also indicated that the alkylation can be achieved in stages with the proviso that the alkylation conditions are less severe in the initial alkylation stage than in a secondary stage, for example, through the use of a lower temperature in the first stage to difference of a higher temperature in a secondary stage. The patent of E.U.A. No. 6,059,962 in the name of Bruce D. Alexander, George A. UHF, Vivek R. Pradhan, William J. Reagan and Roger H. Clayton describes a product of reduced sulfur content that is produced in a multi-stage process from a feed stream comprising a mixture of hydrocarbons and includes aromatic sulfur-containing compounds as unwanted impurities. The first stage includes: (1) subjecting the feed stream to alkylation conditions that are effective to convert a portion of the impurities into products containing higher boiling sulfur and (2) separating the resulting products by fractional distillation into a fraction of lower boiling and a higher boiling fraction. The lower boiling fraction comprises hydrocarbons and has a reduced sulfur content in relation to the feed stream. The highest boiling fraction comprises hydrocarbons and contains aromatic impurities containing unconverted sulfur and also the higher boiling sulfur containing products. Each subsequent step includes: (1) subjecting the highest boiling fraction of the previous step to alkylation conditions that are effective to convert at least a portion of its aromatic content containing sulfur in products containing higher boiling sulfur and (2) separating the resulting products by fractional distillation into a lower boiling hydrocarbon fraction and a higher boiling hydrocarbon fraction containing alkylation products containing sulfur highest boiling. The total hydrocarbon product of reduced sulfur content from the process comprises the lowest boiling fractions of several stages. It is again indicated that the alkylation can be achieved in stages with the alkylation conditions being less severe in the initial alkylation stage than in a secondary stage, for example, through the use of a lower temperature in the first stage as opposed to a higher temperature of a secondary stage. The need to remove certain nitrogen compounds upstream of various processes has also been recognized in the art. For example, the patent of E.U.A. 6,602,405 B2 (Pradhan et al.) Describes a process for producing products having a reduced sulfur content, in which impurities containing basic nitrogen are removed from the feed stream before passing the feed stream to a reaction zone of modification of olefins using a solid phosphoric acid catalyst or an acidic polymer resin catalyst. The patent of E.U.A. 6,599,417 B2 (Pradhn et al.) Similarly shows the removal of basic nitrogen-containing impurities from a feed stream before passing the feed stream to an olefin modification reaction zone. The patent of E.U.A. 6,736,660 B2 (Pradhan et al.) Also shows the removal of organic compounds containing nitrogen upstream of an acid catalyst process. Although the prior art is aware of the need to remove nitrogen-containing molecules upstream of a process based on acid catalysts, the prior art has not recognized that the impact of organic compounds containing non-basic nitrogen is still more severe as a poison of catalyst versus basic or neutral nitrogen compounds. Typical methods described in the art for removing nitrogen-containing molecules such as acid wash steps or acid bed protective techniques will not work to remove these highly harmful non-basic nitrogen compounds. Therefore, there is currently a need for processes to prepare products of reduced sulfur content from a feed stream, wherein the feed stream comprises limited amounts of sulfur-containing organic compounds and containing non-basic nitrogen, wherein the compounds containing harmful non-basic nitrogen can be easily removed before they can act as a catalyst poison. This invention is directed to overcome the problems described above to be able to provide components for the refinery mix of transportation fuels not aggressive to the environment.

BRIEF DESCRIPTION OF THE INVENTION Economic processes for the production of components for refinery blending of transportation fuels by integrated and multi-stage processes are described which include the treatment of a light refinery stream to remove compounds containing non-basic nitrogen, the Chemical conversion of one or more of the sulfur-containing impurities in higher boiling products through alkylation by olefins, and beneficially removing the higher boilers by fractional distillation. This invention contemplates the treatment of various types of hydrocarbon materials, especially hydrocarbon oils of petroleum origin containing sulfur. In general, the sulfur content of oils is more than one percent, and they go up to approximately 2 or 3 percent. The processes of the invention are particularly suitable for the treatment of a refinery feed stream comprising gasoline, kerosene, light naphtha, heavy naphtha and light cycle oil, and preferably a naphtha from a catalytic and / or thermal cracking process . In another aspect, this invention provides a process for the production of products that are liquid at ambient conditions and contain organic sulfur compounds of higher molecular weight than the corresponding sulfur-containing compounds in the feed stream, which process comprises: ) providing a feed stream comprising a mixture of hydrocarbons including olefins, and organic sulfur-containing compounds as well as organic compounds containing non-basic nitrogen, the feed stream is a hydrocarbon-containing material that boils between about 60 ° C and about 4252C and having a sulfur content of up to about 4,000 or 5,000 parts per million and a nitrogen content of up to about 200 parts per million, including a non-basic nitrogen compound content of up to 200 parts per million, (b) pass the feeding current through a lech or of solid adsorbent comprising alkaline or alkaline-earth faujasite-type zeolite, or faujasite zeolites alkaline or alkaline earth metals partially exchanged with H + or transition metals of groups IB, IIB, IVB, VIII, crystalline magnesium silicates and crystalline magnesium silicates exchanged alkaline or mixtures of all the above under conditions suitable for adsorption within the bed, for carry out the adsorption and / or selective complexing of at least a portion of the organic compounds containing non-basic nitrogen contained with the adsorbent, and in this way obtain effluent from the bed containing fewer organic compounds containing nitrogen than the feed stream , (c) in a contacting step at elevated temperatures, contacting the tributary with an acidic catalyst under conditions that are effective to convert a portion of the impurities, for example thiophenes, into a material containing higher molecular weight sulfur through the alkylation by the defines, thus forming a stream of to Suitable feed streams include products from refinery cracking processes consisting essentially of a material boiling between about 60 SC and about 425SC. Preferably, this refinery stream consists essentially of a material boiling between about 602C and about 4002C, and more preferably boiling between about 90 BC and about 3752C. When the selected feed stream is a naphtha coming from a refinery cracking process, the feed stream consists essentially of a material boiling between about 20 ° C and about 250 ° C. Preferably, the feed stream is a stream of naphtha consisting essentially of a material boiling between about 40SC and about 225SC, and most preferably boiling between about 60SC and about 200aC. Beneficially for the processes of the invention, the feed stream comprises a naphtha produced by a catalytic cracking process. Preferably, the olefin content of the feed stream is at least equal on a molar basis to that of the sulfur-containing organic compounds. Suitably a solid catalyst of phosphoric acid is used as the acid catalyst in the step of contacting the alkylation of thiophene. The elevated temperatures used in the contacting step of the thiophene alkylation are on a scale from about 902C to about 2502C, preferably at temperatures on a scale of about 100aC to about 235SC, and most preferably at temperatures in the scale from around 1402C to approximately 220 eC.

This invention is particularly useful for reducing organic sulfur-containing compounds in the feed stream that include compounds in which the sulfur atom is sterically hindered, such as for example multi-ring aromatic sulfur compounds. Typically, organic sulfur-containing compounds include at least sulfides, heteroaromatic sulfides and / or compounds selected from the group consisting of benzothiophenes and substituted dibenzothiophenes. For a more complete understanding of the present invention, reference should now be made to the embodiments illustrated in greater detail in the appended figures and described below by way of examples of the invention.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 graphs the conversion of thiophene with several model feeds containing nitrogen compounds having different degrees of acidity. Figure 2 shows the conversion of thiophene for the runs plotted in Figure 1 as a function of nitrogen adsorbed on the catalyst. Figure 3 graphs the conversion of thiophene as a function of percentage by weight of nitrogen deposited on the catalyst for additional feeds containing nitrogen compounds having varying degrees of acidity. Figures 4, 5 and 6 illustrate graphs showing the conversion of thiophene to various feed streams that are not treated and treated under various different reaction conditions. Figures 7 to 11 show the adsorption capacity of butyronitrile for various adsorbents. Figures 12 and 13 show transition curves for the adsorption of pyrrole and propionitrile. Figures 14 and 15 show transition curves for the adsorption of propionitrile and pyrrole in the presence of an aromatics-containing feed stream. Figure 16 shows the conversion results of thiophene from several feeds treated during different periods with different adsorbents.

DETAILED DESCRIPTION OF THE INVENTION Suitable feed currents for use in this invention are derived from petroleum distillates which generally comprise most refinery streams consisting substantially of hydrocarbon compounds that are liquid at ambient conditions. Petroleum distillates are liquids that boil over a wide or limited range of temperatures within the range of about 10SC to about 345SC. Without However, these liquids are also found in the refining of coal liquefaction products and the processing of schistose oil or tar sands. These distilled feed streams can vary as much as 2.5 weight percent elemental sulfur but generally range from about 0.1 weight percent to about 0.9 weight percent elemental sulfur. The highest sulfur distillate feed streams are generally virgin distillates derived from high sulfur crude, coker distillates and catalytic cycle oils from fluid catalytic cracking units that process relatively higher sulfur feed streams. The nitrogen content of the distilled feed streams in the present invention is also generally a function of the nitrogen content of the crude oil, the hydrogenation capacity of a refinery per barrel of crude capacity and the alternative arrangements of the stream components of the crude oil. hydrogenation feed of distillates. The highest nitrogen distillate feed streams are generally coking distillates and catalytic cycle oils. These distillate feed streams can have total nitrogen concentrations that vary as high as 2,000 parts per million, but generally vary from about 5 parts per million. million to about 900 parts per million. Some refinery streams generally have an API gravity ranging from about 10 APIs to about 1002 APIs, preferably about 10 APIs to about 75 or 1002 APIs, and most preferably about 152 APIs to about 50 APIs for best results. These streams include, but are not limited to, fluid catalytic process naphtha, fluid or delayed process naphtha, light naphtha, hydrocracking naphtha, hydrotreatment process naphtha, isomerates and catalytic reforming and combinations thereof. Catalytic reforming and catalytic cracking process naphtha commonly can be divided into lower boiling scale streams such as light and heavy catalytic naphtha and light and heavy catalytic reforming, which can then be adapted specifically for use as a feed stream according to the present invention. Preferred streams are light virgin naphtha, catalytic cracking naphthas including light and heavy catalytic cracking unit naphtha, catalytic reforming including light and heavy catalytic reforming and derivatives of these refinery hydrocarbon streams. The most suitable feed currents for use in this invention include any of the different complex mixtures of hydrocarbons derived from refinery distillate streams which generally boil on a temperature scale from about 60 BC to about 425 BC. Generally these feed streams comprise a mixture of hydrocarbons, but contain a smaller amount of organic impurities containing sulfur including aromatic impurities such as thiophenic compounds and benzothiophene compounds. Preferred feed streams have an initial boiling point that is below about 792C and have a distillation end point that is about 345 SC or less, and most preferably about 249aC or lower. If desired, the feed stream may have a distillation end point of about 2212C or lower. It is also anticipated that one or more of the above distilled streams may be combined to be used as a feed stream. In most cases the fuel efficiency for refinery transportation or fuel refinery transportation mixture components obtained from the different alternative feed streams can be comparable. In such cases, logistics such as the volume availability of a current, location of the closest connection and short-term economy can be determinant in terms of what current is used. Catalytic cracking products are highly preferred feed streams for use in this invention. Feeding streams of this type include liquids boiling below about 345 BC; such as light naphtha, heavy naphtha and light cycle oil. However, it will also be appreciated that the complete output of volatile products from a catalytic cracking process can be used as a feed stream in the present invention. Catalytic cracking products are a desirable feedstock because they typically contain a relatively high define content, which usually makes it unnecessary to add any additional alkylating agent during the first alkylation step of the invention. In addition to sulfur-containing organic compounds, such as mercaptans and sulfur, aromatic sulfur-containing compounds, such as thiophene, benzothiophene, and thiophene and benzothiophene derivatives, are frequently a major component of sulfur-containing impurities in cracking products. catalytic, and these impurities are easily removed by means of the present invention. For example, a typical light naphtha of fluidized catalytic cracking of a petroleum derived gas oil may contain up to about 60 weight percent olefins and up to about 0.5 weight percent. one hundred percent by weight of sulfur where the majority of sulfur will be in the form of thiophene and benzothiophene compounds. A preferred feed stream for use in the practice of this invention will comprise catalytic cracking products and furthermore comprise at least 1 weight percent olefins. A feed stream that is too preferred will comprise catalytic cracking products and will further comprise at least 5 weight percent olefins. These feed streams can be a portion of the volatile products of a catalytic cracking process that are isolated by distillation. In the practice of this invention, the feed stream will contain aromatic sulfur-containing compounds as impurities. In one embodiment of the invention, the feed stream will contain both thiophene and benzothiophene compounds and impurities. If desired, at least about 50 percent or even more of these sulfur-containing aromatics can be converted into higher-boiling sulfur-containing material in the practice of this invention. In one embodiment of the invention, the feed stream will contain benzothiophene, and at least about 50 percent of the benzofiofen will be converted to higher boiling sulfur containing material by alkylation and removed by fractionation.

Any acid material exhibiting an ability to increase alkylation of aromatics containing sulfur by olefins or alcohols can be used as a catalyst in the thiophene alkylation zone of the present invention. Although liquid acids, such as sulfuric acid, can be used, solid acid catalysts are particularly desirable, and these solid acid catalysts include liquid acids which are supported on a solid substrate. Solid acid catalysts are generally preferred over liquid catalysts because of the ease with which the feed can be contacted with this material. For example, the feed stream can be simply passed through one or more fixed beds of acid catalyst into solid particles at a suitable temperature. As desired, different acid catalysts can be used in the different steps of the invention. For example, the severity of the alkylation conditions may be moderated in the alkylation step of the subsequent step through the use of a less active catalyst, while a more active catalyst may be used in the alkylation step of the initial step. Catalysts useful in the practice of the invention include acidic materials such as catalysts comprising acidic polymeric resins, supported acids and acid inorganic oxides. Suitable acidic polymeric resins include the polymeric sulfonic acid resins which are well known in the art and commercially available. A berlyst® 35, a product produced by Rohm and Haas Co. , is a typical example of this material. Supported acids that are useful as catalysts include but are not limited to Bronsted acids (examples include phosphoric acid, sulfuric acid, boric acid, HF, fluorosulfonic acid, trifluoromethanesulfonic acid and dihydroxy fluoroboric acid) and Le is acids (examples include BF3, BC13, AlBr3, FeCl2, FeCl3, ZnCl2, SbF5, SbCl5 and combinations of A1C13 and HC1) which are supported on solids such as silica, alumina, silica-aluminas, zirconium oxide or clays. The supported catalysts are typically prepared by combining the desired liquid acid with the desired support and drying. Supported catalysts that are prepared by combining a phosphoric acid with a support are highly preferred and are mentioned herein as solid phosphoric acid catalysts. These catalysts are preferred since they are both highly effective and low in cost. The patent of E.U.A. No. 2,921,081 (Zimmerschied et al.), Which is incorporated herein by reference in its entirety, describes the preparation of solid phosphoric acid catalysts at combining a zirconium compound selected from the group consisting of zirconium oxide and the zirconium halides, with an acid selected from the group consisting of ortho-phosphoric acid, pyrophosphoric acid and triphosphoric acid. The patent of E.U.A. No. 2,120,702 (Lpatieff et al.) Which is incorporated herein by reference in its entirety, describes the preparation of a solid phosphoric acid catalyst by combining a phosphoric acid with a siliceous material. British Patent No. 863,539, which is hereby incorporated by reference in its entirety, also describes the preparation of a solid phosphoric acid catalyst by depositing a phosphoric acid on a solid siliceous material such as diatomaceous earth or kieselguhr. When a solid phosphoric acid is prepared by depositing a phosphoric acid on kieselguhr, it is believed that the catalyst contains: (i) one or more free phosphoric acids, ie, ortho-phosphoric acid, pyrophosphoric acid and / or triphosphoric acid, and ( ii) silicon phosphates which are derived from the chemical reaction of the acid or acids with the kieselguhr. Although it is believed that anhydrous silicon phosphates are inactive with an alkylation catalyst, it is also believed that they can be hydrolyzed to produce a mixture of ortho-phosphoric and polyphosphoric acids that is catalytically active. The precise composition of this Mixing will depend on the amount of water to which the catalyst is exposed. To maintain a solid phosphoric acid alkylation catalyst at a satisfactory level of activity when used with a substantially anhydrous hydrocarbon feed stream, it is conventional to practice adding a small amount of water or an alcohol, such as isopropyl alcohol, to the stream of feed to maintain the catalyst at a satisfactory level of hydration. It is believed that the alcohol undergoes dehydration after contact with the catalyst, and that the resulting water then acts to hydrate the catalyst. If the catalyst contains too little water, it tends to have a very high acidity which can lead to a rapid deactivation as a result of the coking and, in addition, the catalyst will not possess an adequate physical integrity. The additional hydration of the catalyst serves to reduce its acidity and reduce its tendency towards rapid deactivation through the formation of coke. However, excessive hydration of this catalyst can cause the catalyst to soften, physically agglomerate and create high pressure drops in fixed-bed reactors. Consequently, there is an optimum level of hydration for a solid phosphoric acid catalyst, and this obvious hydration will be a function of the reaction conditions, the substrate and the alkylating agent. In preferred embodiments of the invention using solid phosphoric acid catalysts, a hydrating agent is required in an amount exhibiting the ability to improve catalyst performance. Suitably, the hydrating agent is at least one member of the group consisting of water and alkanols having about 2 to about 5 carbon atoms. An amount of hydrating agent that provides a concentration of water in the feed stream in the range of about 50 to about 1,000 parts per million is generally satisfactory. This water is conveniently provided in the form of an alcohol such as an isopropyl alcohol. Acid inorganic oxides which are useful as catalysts include but are not limited to aluminas, silica-aluminas, natural and synthetic stratified clays and natural and synthetic zeolites such as faujasites, mordenites, L, omega, X, Y, beta and ZSM zeolites. Highly suitable zeolites include beta, Y, ZSM-3, ZSM-4, ZSM-5, ZSM-18 and ZSM-20. Desirably, the zeolites are incorporated into an inorganic oxide matrix material such as a silica-alumina. In fact, the equilibrium cracking catalyst can be used as the acid catalyst in the practice of this invention. The catalysts may comprise mixtures of materials different such as Lewis acid (examples include BF3, BCI3, SbF5 and AICI3), a non-zeolitic solid inorganic acid (such as silica, alumina and silica-alumina), and a large pore crystalline molecular sieve (examples include zeolites, clays stratified and aluminophosphates). A solid catalyst will desirably be in a physical form that will allow rapid and effective contact with reagents in the process step when it refuses. Although the invention should not be so limited, it is preferred that a solid catalyst be in the form of particles wherein the largest dimension of the particles has an average value ranging from about 0.1 mm to about 2 cm. For example, substantially spherical spheres of catalyst can be used which have an average diameter of about 0.1 mm to about 2 cm. Alternatively, the catalyst can be used in the form of bars having a diameter on the scale from about 0.1 mm to about 1 cm and a scale length of 0.2 mm to about 2 cm. As indicated above, the feed streams used in the practice of this invention will contain organic compounds containing nitrogen as impurities in addition to the organic impurities containing sulfur. Many of the typical nitrogen-containing impurities are organic bases and, in some cases, can cause deactivation of the acid catalyst or catalysts in the present invention. It has now been discovered that the catalyst poisons with the most harmful organic nitrogen-containing molecules are organic molecules containing non-basic nitrogen. It has been found that typical commercial food streams used in a thiophene alkylation process will contain a majority, commonly greater than 75 mole percent, of non-basic nitrogen compounds, ie, either neutral or slightly acidic nitrogen compounds. These compounds include acetonitriles, propionitriles, butyronitriles, pyrroles, pyridine and amines. Without wishing to be limited by theory, it is believed that non-basic nitrogen compounds are converted into basic compounds in the acid catalyst active sites. These non-basic nitrogen compounds were generally not removed by acid washing steps, after water washing steps or guard bed stages using for example a Lewis acid adsorbent guard bed which could remove basic nitrogen compounds before exposure to the acid catalyst. It is believed that non-basic nitrogen compounds selectively poison the active catalyst sites in the acid catalyst since these are the sites that convert non-basic nitrogen compounds into basic nitrogen compounds. Typically a light to medium fluidized catalytic cracking gasoline feed stream can have 10-25 ppmw of non-basic nitrogen compounds while a heavier feed can have more than 50 ppmw of non-basic nitrogen compounds. According to the process of the present invention these non-basic nitrogen compounds have to be removed and can be removed by using a combination of a wash with base followed by an acid wash; an adsorbent or a combination of adsorbents that can be regenerated; or an acidic material that preferentially reacts with non-basic nitrogen to form basic nitrogen compounds that can then be adsorbed. A combination of the three processes mentioned above can also be used to remove non-basic nitrogen compounds. According to the invention, the combination of acid-based wash-washing can be carried out at temperatures ranging from about 0 to about 100 degrees centigrade and preferably around 20 to about 50 degrees centigrade, and the pressures may vary from about 0 to about 100 7.03 kg / cm2 gauge, preferably around .0703 to about 1.75 kg / cm2 gauge. The right basic solutions include bases inorganic such as sodium hydroxide or potassium hydroxide with base concentrations in the range of about 5 to about 50% (p), preferably about 10 to about 20% (p). The base solution is recirculated to provide a contact ratio of between 10-100 volumes of solution to volume of a crude feed, most preferably a ratio of about 50 to about 100 volumes of solution to the feed volume. Suitable acidic solutions include inorganic acids such as sulfuric acid with acid concentrations in the range from about 5 to about 25% by weight, preferably about 10 to about 20% by weight. The acid wash can be done in one to three contacting steps, most preferably a contacting step. The acidic solution is recirculated to provide a contact ratio of between 10-100 volumes of solution: oil feed, most preferably 50-100 volumes of solution to volume of oil feed. The basic wash should be done first, followed by acid washing, to protect the acid catalyst from any base residue from the base wash step. According to the present invention, the adsorbents of effective non-basic nitrogen compounds include alkaline or alkaline-earth faujasite zeolites, or alkaline or alkaline-earth faujasite zeolites partially exchanged with H + or transition metals of groups IB, IIB, IVB, VIII, crystalline, magnesium silicates, crystalline magnesium silicates exchanged and alkaline or mixtures of all the above. The adsorbent can also be a physical mixture of sepiolite, Na-X and Na-Y zeolites wherein these components are present in amounts ranging from 5 to 95% by volume each. The adsorption may be carried out at temperatures from about 0 to about 100 degrees C, preferably from 20 to about 40 degrees C, and the pressures may vary from about 0 to about 21 kg / cm 2 gauge, and preferably from about 7.03. at approximately 10.5 kg / cm2 gauge. The weight hourly space velocity ("WHSV") of feed to adsorbent, may vary from about 0.5 to about 50 hour "1, most preferably between about 10 to about 15 hr" 1. The amount of adsorbent may be an amount sufficient to run between about 0.5 and about 15 days between regenerations, most preferably from about 1 to about 5 days between regenerations.

The regeneration of the spent adsorbent can be achieved either by heat treatment, solvent washing or desorption by pressure fluctuations. These methods include oxidation at a high temperature at conditions that include temperatures of about 100 to about 1,000 degrees C, preferably about 100 to about 500 degrees centigrade and pressures of about 0 to about 7.03 kg / cm 2, and preferably about 0 to about 3.51 kg / cm2 in the presence of oxygen-containing gas. Pyrolysis conditions at high temperatures include temperatures of from about 100 to about 1,000 degrees C, and preferably from about 100 to about 500 degrees C and pressures from 0 to about 7.03 kg / cm2, preferably from about 0 to about 3.51. kg / cm2. Hydrotreating conditions at high temperatures include temperatures of about 500 to about 700 degrees C and pressures of about 25 to about 40 atmospheres of pressure in the presence of a gas containing hydrogen. For a solvent wash, an effective solvent is toluene, since it is based on a refinery. It is also believed that many other oil-based refinery currents will be also effective as regeneration solvents. The regeneration of the solvent is generally carried out under conditions including temperatures of about 10 to about 204 degrees C and about 0 to about 21 kg / cm 2 gauge pressure, and most preferably about 10 to about 65.5 degrees C and 0 at approximately 3.5 kg / cm2 gauge. In addition, a pressure fluctuation operation can be carried out to regenerate the catalyst at conditions that include temperatures from about 37.7 to about 260 degrees C and pressures from about 0 to about 3.5 kg / cm2 of pressure using a scavenging or purging gas. such as nitrogen. Appropriate methods that remove basic nitrogen-containing impurities have so far typically been involved in treatment with an acidic material. These methods include methods such as washing with an aqueous solution of an acid and the use of a guard bed which is placed in front of the acid catalyst. Examples of effective guards include but are not limited to A-zeolite, Y-zeolite, L-zeolite, mordenite, fluorinated alumina, fresh cracking catalyst, equilibrium cracking catalyst and acidic polymer resins. Although a guard bed technique is employed, it is commonly desirable to use two guard beds in such a way that one bed can be regenerated while the other is being used to pre-treat the feed stream and protect the acid catalyst. If a cracking catalyst is used to remove basic nitrogen-containing impurities, the catalyst can be regenerated in the regenerator of a catalytic cracking unit when it has been deactivated with respect to its ability to remove those impurities. If an acid wash is used to remove compounds containing basic nitrogen, the feed stream will be treated with an acid solution of a suitable acid. Suitable acids for this use include but are not limited to hydrochloric acid, sulfuric acid and acetic acid. The concentration of acid in the aqueous solution is not critical, but is conveniently selected to be in the range of about 0.1 percent to about 30 percent by weight. For example, a 2 weight percent solution of sulfuric acid in water can be used to remove compounds containing basic nitrogen from a heavy naphtha from a catalytic cracking process. In the practice of this invention after the compounds containing non-basic nitrogen, the feed to the alkylation step is contacted with the acid catalyst at a temperature and for a period of time which are effective to result in the degree of desired conversion of organic impurities containing sulfur selected to a material containing higher boiling sulfur. The contact temperature will desirably be in excess of about 50 SC, preferably more than 852C and most preferably more than 100 BC. The contacting will generally be carried out at a temperature in the range of about 50 SC to about 2602C, preferably around 85 BC to about 220AC and most preferably around 100EC to about 2002C. It will be appreciated, of course, that the optimum temperature will be a function of the acid catalyst used, the alkylating agent or agent selected, the concentration of alkylating agent or agents, and the nature of the sulfur-containing aromatic impurities that are to be removed. The effluent from the acid catalyst contacting stage can then be fractionated into at least a low boiling fraction and consists of a sulfur-free fraction and a high boiling fraction containing a portion of the boiling sulfur containing materials plus high as shown for example in the US patent 6,736,963, whose teachings are incorporated herein by way of reference. This invention is a multi-stage integrated process for concentrating sulfur-containing aromatic impurities from a hydrocarbon feed stream in a relatively small volume of high boiling material. As a result of this concentration, the sulfur can be disposed of more easily and at a lower cost, and any conventional method can be used for this waste. For example, this material can be mixed in heavy fuels where the sulfur content is less objectionable. As an alternative, it can be hydrotreated efficiently at a relatively low cost thanks to its reduced volume in relation to that of the original supply current. In another embodiment it is believed that the removal of non-basic nitrogen compounds by the adsorbents of the present invention also increases the yield of other processes using solid acid catalysts such as condensation or the condensation process or catalytic polymerization used to produce poly-gasoline. from light olefins. A variety of commercial chemical and petrochemical processes include the condensation reaction of an olefin or a mixture of olefins on an acid catalyst to form products of higher molecular weight. This process is referred to herein as a polymerization process, and the products can be either low molecular weight oligomers or high molecular weight polymers. The oligomers are formed by the condensation of 2, 3 or 4 molecules of olefin with one another, while the Polymers are formed by the condensation of 5 or more olefin molecules with each other. As used herein, the term "polymerization" is used to refer to a process for the formation of oligomers and / or polymers. Low molecular weight olefins (such as propene, 2-methylpropene, 1-butene and 2-butene) can be converted by polymerization onto a solid acid catalyst (such as a solid phosphoric acid catalyst) in a product comprising oligomers and It is of value as a feed stream of high octane gasoline blending and as a starting material for the production of chemical intermediates and final products that include alcohols, detergents and plastics. This process is typically carried out on a fixed bed of solid acid catalyst and at elevated temperatures and pressures. These polymerization processes are described in greater detail in the U.S. patent. No. 5,932,778, the teachings of which are hereby incorporated by reference.

Example 1 Figure 1 shows a graph of the results of four runs in a pilot plant using an acid catalyzed thiophene alkylation process. Plus specifically, the runs were carried out with model feed streams two of which contained the non-basic nitrogen containing propionitrile compound and two of which contained the basic nitrogen-containing compound butylamine. The conversion with thiophene is plotted on the Y axis in molar percentage of thiophene converted as a cumulative feed function charged to the catalyst plotted on the X axis. Figure 2 shows the same graph of conversion with thiophene as a function of weight percentage of nitrogen in the catalyst. As can easily be seen from an inspection of the graph, the presence of non-basic nitrogen compounds in the feed results in a marked reduction in thiophene conversion activity against feeds that only have basic nitrogen compounds present. The wave pattern feed compositions used in the runs illustrated in Figures 1 and 2 are shown below in Table 1.

Table 1 Feeding inspections model Runs of runs of propionitrile butylamine 2-Methyl-2-butene 20% by weight 20% by weight 4-Meti1-1-petent 20% by weight 20% by weight Hexane 60% by weight 60% by weight Thiophene 160 ppm 153 ppmmp 2-Methylthiophene 160 ppm 153 ppmmp 3-Methy1thiophene 160 ppm 150 ppmmp Propionitrile 45 ppm (as 51.6 ppm (as nitrogen) nitrogen) The pilot plant used to generate the data in Figures 1 and 2 was loaded with 54 cc of a solid phosphoric acid catalyst (C84-5-02 supplied by Süd CEIME, Inc. Louisville, Ky., USA) which was crushed up to a Tyler screen size of -12 + 20 (USA Standard Testing Sieve by WS Tyler). The pilot scale reactor consisted of a 34-inch long stainless steel pipe with ¾ D.E. x 1.57 centimeters of D.I. x 0.16 centimeters of wall. The reactor temperatures were maintained by four electrically heated sections of the reactor wall inside a blast furnace box isolated The temperatures of these actions were controlled by a programmable computer with the use of single-point thermocouples in each of the reactor wall sections. There was also a stainless steel thermowell with 0.31 centimeters of D.E. that ran along the middle of the reactor from the top. This thermowell housed the thermocouple of several points (thermocouple of several points of three points with separations of 50.8 centimeters) to monitor temperatures throughout the reactor. The pilot plant reactor consisted of a preheating zone (temperature zone 1) which is filled with the alumina fragments, sieved to a Tyler sieve size of -12 +20 (USA Standard Testing Sieve by WS Tyler ). The second and third heated zones were loaded with 54 cc of a solid phosphoric acid catalyst (C84-5-02 supplied by SudChemie, Inc. Louisville, Ky., USA) which was crushed to a Tyler mesh size of -12 + 20 (USA Standard Testing Sieve by WS Tyler). The rest of the reactor (temperature zone 4) was filled with the alumina fragments, sieved to a Tyler sieve size of -12 + 20 (USA Standard Testing Sieve by WS Tyler) as a cooling zone and to support the catalyst. The feed stream of the process was introduced into the reactor using a dosing pump by precision syringe (ISCO). The feed was preheated to the reaction temperature in the preheating zone of the reactor and measured along the center line by thermocouples in various positions, and the heating zones were adjusted accordingly. The liquid product from the reactor was passed in a cooled high pressure separator / receiver where nitrogen was used to maintain the reactor outlet pressure at the desired operating pressure. The pressure was controlled by a Badger Research control valve in the separator / receiver outlet gas. The liquid samples were drained from the high pressure receiver / separator and analyzed by gas chromatograph of several columns for speciation of sulfur, speciation of nitrogen and speciation of olefin. For these experiments, 54 cc of catalyst were charged to the reactor. The feed flow rates were operated to achieve a liquid hydraulic space velocity (standard volume of feed in cc / hour divided by volume loaded catalyst in ce) of 3.0 hr-1. The temperature of the reaction zone was maintained at 177 C +/- -152C and 28.1 kg / cm2 gauge +/- 703 kg / cm2 gauge. The conditions used for each run included: LHSV 3.0 hr "1 Pressure 28.1 kg / cm2 gauge Temperature 1772C The following table 2 below shows the real data plotted in figures 1 and 2.

Table 2 Proionitrile # 1 run Propionitrile Run # 2 Butylamine Run # 1 Butylamine Run # 2 Example 2 Figure 3 shows a graph of the results of additional pilot plant runs using an acid catalyzed thiophene alkylation process. More specifically, the runs were carried out with model feeds containing 80 ppmw of various nitrogen compounds, both non-basic and basic nitrogen compounds. In Figure 3, the conversion of thiophene is plotted on the Y axis in molar percentage of thiophene converted as a function of the percentage by weight of nitrogen adsorbed on the catalyst. An inspection of the graph clearly shows that the more basic the nitrogen compound, the flatter the curve, ie the deactivation of the catalyst. The presence of non-basic nitrogen compound in the feed results in a marked conversion of the thiophene conversion activity against feeds having only basic nitrogen compounds present. Preliminary experimentation was carried out to determine a special speed that could produce a thiophene conversion of approximately 95% using the feed based (50% 1-hexene, 50% n-heptane, 200 ppm S as thiophene) that could allow the experimental program to clearly and quickly determine the poisoning effect of nitrogen contaminants in the feeding. Based on this preliminary work, a spatial velocity (WHSV) of 4.1 hr-1 is selected with the rest of the experiments. For the experiments carried out in the present example, the following base feed was used: 50% 1-hexene 50% 1-heptane 200 ppm sulfur (as thiophene) 80 ppmw N (as various nitrogen contaminants) The following nitrogen contaminants are evaluated added to the base feed: None Propionitrile (non-basic) Methylpyrrole (non-basic) Aniline (basic) Butylamine (basic) Pyrrole (non-basic) Pyridine (non-basic) Butyronitrile (non-basic) More specifically, the results show that the different nitrogen compounds can be classified based on the impact of poisoning in the process of alkylation of thiophene catalyzed by acid in: (1) highly poisonous compounds for the process such as pyridine, methylpyrrole, propionitrile and butyronitrile; (ii) moderately poisoning compounds for the process-aniline and pyrrole; and (iii) low-level poisoning compounds for the alkylation process of thiophene-butylamine. Under the reaction conditions employed in the present example, most of the nitrogen compounds were completely retained in the catalyst during the first days of reaction. For longer times the adsorption of nitrogen in stream was slightly reduced, especially for the nitrile compounds. The solid phosphoric acid catalyst used in the runs of the pilot plant of the present example was a commercially available catalyst designated C-84-05 obtained from Süd Chemie Inc., Louisville, KY, E.U.A. The pilot plant was charged with 300 mg of a solid phosphoric acid catalyst that was crushed to a Tyler mesh size of 0.4 - 0.6 mm. The catalyst was dried under the influence of nitrogen for 2 hours at 2002C before use. The pilot plant consisted of parallel fixed bed reactors, each capable of containing between 50 to 1,000 mg of catalyst. The design of the pilot plant was similar to the design described above. The reactors were operated in a downflow operation. The conditions used for each run were: LHSV 4.1 hr "1 Pressure 28.1 kg / cm2 manometer Temperature 180 SC The data plotted in figure 3 is shown below in table 3: Table 3 @ 8 hours @ 8 hours @ 8 hours @ 32 hours% @ 32 hours @ 32 hours average Composite% Nitrogen Conversion% Nitrogen Conversion of N absorption in thiophene absorption absorption in thiophene of catalyst (%) of catalyst (% ) nitrogen (%) nitrogen nitrogen (%) 0.00 92% 92% Propionitril 98% 0.18% 62% 89% 94% 0.74% 2% 0 Methylpyrrole 100% 0.18% 84% 38% 69_% 0.54% 1% Aniline 100% 0.18% 83% 100% 00% 0.79% 23% Butylamine 100% 0.18% 85% 100% 100% 0.79% 86% Pyrrole 100% 0.18% 79% 100% 100% 0.79% 45% Pyridine ^ 100% 0.18% 91% 82% 91% 0.72% 1% Butironitrile 55% 0.10% 52% 15% 35% 0.28% 13% Example 3 Table 4 illustrates the feed inspections for a feed stream of thiophene alkylation process catalyzed with commercial acid containing all indigenous non-basic nitrogen compounds and for feed treated to remove nitrogen, first by washing with acid and second by treatment with resin. This commercial feed is a gasoline cut of fluidized catalytic cracking (FCC) of light cutting scale. This feed, typical of the type of feed processed by a catalyzed thiophene alkylation process unit With acid, you can see that it contains a wide variety of nitrogen compounds. These nitrogen compounds can be separated into three general classifications: (1) basic nitrogen species including butylamine, test and pyridine; (2) neutral compounds including acetonitrile, propionitrile and butyronitrile and (3) a little acid nitrogen compounds including pyrroles. The acid wash mainly removed the basic nitrogen compounds, leaving behind most of the non-basic nitrogen compounds. In particular, butyronitrile has limited solubility in water and does not tend to be removed by acid washing. A treatment of the feed with a resin was able to remove additional levels of the non-basic nitrogen compounds.

Table 4 Speciation of standard feed nitrogen treated in the pilot plant A series of experiments with untreated commercial feed and commercial feed was carried out that was washed with acid and treated with resin to remove most of the nitrogen in the feed. Figures 4, 5 and 6 below illustrate graphs demonstrating the conversion of thiophene on the Y-axis in molar percentage of thiophene conversion units plotted as a function of total feed grams, total grams of feed fed to the reactor of the pilot plant divided between the grams of catalyst charged in the reactor and hours in oil, respectively both for the untreated feed and for the feedings treated with resin and washed with acid at different space velocities and catalyst loads as indicated in the figures. The pilot plant units were operated at: (i) a space velocity of 1.5 hr "1, (ii) a space velocity of 3.0 hr" 1 with the same amount of catalyst as that charged in (i) and twice the feed flow velocity and (iii) a space velocity of 3.0 hr "1 by reducing the amount of catalyst charged in the reactor to the middle of case (i) .The different space velocities were run to more clearly distinguish the effect of stirring nitrogen of the feed As can be seen from these data, the productivity of the catalyst (grams of feed processed per gram of catalyst) at a high conversion of thiophene (> 80%) is increased by more than a factor of 3 when the feeding was pretreated to remove most of nitrogen species used. Most of the nitrogen removed was non-basic nitrogen species for this commercial feed stream. The pilot plant used in the present example is the same as the pilot plant described in example 1. The process conditions for each run were the following except as shown in figures 4, 5 and 6. LHSV as indicated in Figures 4, 5 and 6 Temperature: 1802C Pressure: 28.1 kg / cm2 gauge An inspection of the graph clearly shows a markedly reduced thiophene conversion activity in an acid catalyzed thiophene alkylation reaction for commercial feeds containing non-basic nitrogen.

Example 4 Table 5 below shows the results of two titrations carried out with two bases: pyridine and 2,6-di-tert-butylpyridine in a commercially available solid phosphoric acid catalyst obtained from Süd-Chemie Inc. These titrations were performed as follows: The catalyst samples were crushed and sieved. Agglomerates with diameters of 180-355 mm were loaded in a fixed-bed pilot plant reactor. Samples (50 mg) were treated in He (1.33 cm3 s "1) and flow at 453 K for one hour before taking titration measurements Liquid mixtures of n-hexane (Fluka, 99.5%, 4.5 ml) with pyridine (Fischer, 99.9%, 20 ml) or 2,6-di-tert-butyl-pyridine (Aldrich, 97%, 50 ml) were prepared.The resulting mixture was introduced in a stream of He (1.33 cm3 s "1) at a liquid volumetric flow rate of 0.09 cm3 tT1 resulting in mixtures with 0.3 kPa of n-hexane and 5.3 Pa of pyridine or 4.7 Pa of 2, β-di-er-butylpyridine. The temperature of the catalyst bed was 453 aK. The amount of titrant adsorbed on the catalyst was calculated from its concentration in the effluent, measured by gas chromatography (Hewlett-Packard 6690 GC, 30 m HP-1 capillary column of methyl silicon, flame ionization detector). Without wishing to be limited by theory, Table 5 shows that there are two types of acid sites in the SSPA catalysts: a set of strong acid sites (those titrated by 2,6-di-er-butylpyridine) and a set of sites of weaker acids (difference between those titrated by pyridine and those titrated by 2,6-di-tert-butylpyridine). It is believed that strong acid sites are instrumental in carrying out the conversion of thiophene. These strong acid sites are poisoned selectively by non-basic nitrogen compounds since non-basic compounds will not adsorb onto the weak acid sites, but will react on the strong acid sites to create products that are basic and will then be strongly adsorbed on the strong acid sites. This reaction of the non-basic nitrogen compounds at the strong acid sites thus removes the sites required for the thiophene alkylation and amounts to the very high propensity for the non-basic nitrogen compounds to poison the thiophene alkylation reaction.

Table 5 SPA titration Titrator Titrator GN / g cat% by weight of N Titrant PM umol / g G / g cat G / g cat% Piridine 78 612.5 0.047775 0.008575 0.86% 2,6-di- 192 214.4 0.041165 0.003002 0.30% ter - butilpiri dina Therefore, from the above examples, it is apparent that there is a significant need for a process to effectively remove a wide variety of nitrogen compounds, especially the compounds of non-basic nitrogen, from the commercially available thiophene alkylation feed. The following examples describe process options according to the present invention which are suitable for removing these non-basic nitrogen compounds from a commercial thiophene alkylation feed stream.

Example 5 The experiments described in this example have been carried out in a multiple fixed bed adsorption system. Four fixed-bed stainless steel reactors were connected in parallel to a common power inlet. Liquid feed was introduced by means of a double-lath pump, capable of maintaining a constant flow while minimizing the piston pulses. The design of the system allowed an upward flow or downflow of the feed through an 'adsorbent bed. Cumulative liquid samples were taken at the outlet of the tubes at predetermined time intervals and analyzed by gas chromatography. A Varian-3380 GC equipped with an FID and a Flame-Driven Photometric Detector (PFFD) that works in nitrogen mode was used to analyze the output current. Propionitrile, butyronitrile, pyrrole and thiophene were detected by PFPD, while heptane and hexene-1 were detected by the FID, both detectors working in parallel. The different compounds were separated on a CP-SII 24-CB column. The adsorption experiments were carried out at room temperature, at a pressure of 3.5 bar and WHSV in the range of 15-20 h "1. The amount of adsorbent used was two grams, and in all cases it had been dried (2H / 200SC in 100 ml of N2 flow) and compacted with n-heptane before introducing the nitrogen-containing feed at a constant flow of about 1.0 ml / min.Speed velocity was determined in each case based on the amount of processed feed recovered at the output of the reactors.

Adsorption of Butyronitrile Table 6 Adsorbents used for the removal of butyronitrile Adsorbent Characteristics Zeolite Na-Y CBV-100 (Zeolyst Intl.), Si / Al = 2.6 Magnesium silicate Natural magnesium silicate with natural crystalline structure Phosphoric acid Solid commercial solid phosphoric acid catalyst supplied by Sud Chemie FCC ECAT cracking catalyst, 800 ppm Ni, 2,000 ppm V, of commercial equilibrium UCS = 24.32 Á H-Montmorilonite Montmorilonite treated with acid (6h, 0.2M HC1 solution, room temperature) Cu-Hydrotalcite Al3 + / (Al3 ++ Cu2 ++ Mg2 +) = 0.25; Cu2 + / (Cu2 ++ Mg2 +) = 0.5 (molar ratios) Zn-Hydrotalcite A13 + / (Al3 ++ Zn2 ++ Mg2 +) = 0.25; Zn2 + / (Zn2 ++ Mg2 +) = 0.5 (molar ratios) Ni-Hydrotalcite A13 + / (Al3 ++ Ni2 ++ Mg2 +) = 0.25; Ni2 + / (Nl2 ++ Mg2 +) = 0.13 (molar ratios) Cu- Y Y zeolite CCBV-100 changed with Cu (2.7% p Na20, 15.8% p CuO) Changed with natural Na Sepiolite changed with Na (4.4t% of Na20) Sepiolite The adsorbents used and their main characteristics are described in Table 6. In the run using a commercial solid phosphoric acid catalyst, the original catalyst pellets were ground and sieved to a particle size of 0.4-0.6 mm, and the adsorption was carried out twice to review the capacity of reproduction of experimental protocol. The remaining adsorbents were similarly pressed, crushed and sieved to the same particle scale (0.4-0.6 mra) except for FCC ECAT, which was already in the form of microspheres. The base model feed contained n-heptane (50% by weight), hexene-1 (50% by weight) and thiophene (200 ppm S) and was splashed with 80 ppmmp of nitrogen such as butyronitrile. This model feed was passed through the adsorbents described above in table 6.

Adsorption Results The results for the commercial solid phosphoric acid catalyst are illustrated in Figure 7 (transition curve) and Table 7, and show that good reproducibility exists. The values set forth in Table 7 as adsorption capacities are determined as the amount of nitrogen adsorbed per 100 g of adsorbent, just before any N is detected in the effluent stream. It can be seen that the adsorption capacity for butylonitrile under these conditions is relatively low. The comparative results for the remaining adsorbents are also shown in table 7 and illustrated in figures 9 to 11. In figure 8, commercial solid phosphoric acid catalyst is compared with different adsorbents based on hydrotalcite. Figure 9 shows a comparison of a commercial solid phosphoric acid with two Y zeolites, a commercial Na-Y zeolite (CBV-100, obtained from Zeolyst Intl.), And exchanged with Cu, two sepiolites: a natural sepiolite and an exchanged sepiolite with Na. Figure 10 compares the commercial solid phosphoric acid with a FCC ECAT, a montmorilonit exchanged with acid and with adsorbents based on hydrotalcites, Y zeolite and sepiolite. After passing 173 g of feed stream through the bed of 2 g of NaX adsorbent under the conditions described above, no butyronitrile was detected in the exit stream. Thus, Na-Y exchanged with copper had a minimum nitrogen adsorption capacity of 0.69 g N / 100 g of adsorbent. Y zeolite exchanged with copper also showed a considerable adsorption capacity. This test was repeated and the data is confirmed as can be seen in table 7 and figure 11. Finally, sepiolite-based adsorbents also give high adsorption capacities of butyronitrile.

Table 7 Adsorption capacities for the different adsorbents Example 6 Adsorption of propionitrile and pyrrole In this example the base model feed contained n-heptane (50% by weight), hexene-1 (50% by weight) and thiophene (200 ppm of S) and was spread with 40 ppm of propionitrile and 40 ppm of pyrrole. This feed was passed through adsorbents of Na-Y and Sepiolite to thereby assess the relative adsorption capacities of each adsorbent with respect to each nitrogen compound. The transient adsorption curves are shown in Figures 12 and 13. The nitrogen adsorption capacities are summarized in Table 8.

Table 8 Adsorption capacity of nitrogen compounds of Na-Y and Sepiolite WHSV adsorbents 15-20 hr "1, room temperature, 4 bars (splashed with 40 ppmN for each compound N) gr N / 100 grams of adsorbent Gr N / 100 gr adsorbent Adsorbent Pirrol PN Sum Food NA-Y> 0.52> 0.83> 1.35 base Sepiolite 0.05> 0.76> 0.84 Food NA-Y 0.1> 1.3> 1.4 base + 30% aromatics Sepiolite 0.017 0.28 0.3 Example 7 Effect of aromatics on the adsorption of propionitrile and pyrrole To evaluate the influence of the presence of aromatics in the feed, the following model feed was prepared: 35% n-heptane, 35% 1-hexene, 22% toluene , 8% o-xylene, 200 ppm thiophene and 40 ppm PN and 40 ppm pyrrole. This feed was passed through adsorbents of Na-Y and Sepiolite. The transition curves of the adsorption of these experiments are shown in figures 14 and 15. These transition curves were obtained at 15-20 hr "1 WHSV, at room temperature and at a pressure of 4 bar. Nitrogen capacity can also be observed in table 8, where the adsorption capacities are shown.

Example 8 Regeneration of NaY Adsorption on fresh NaY allows a high adsorption capacity for propionitrile and pyrrole when a base feed spiked with 80 ppm of N as propionitrile and 80 ppm of N as pyrrole is passed through zeolite put on a bed fixed. The regeneration of NaY used was carried out either by calcination at 2002C for 12 hours or by washing.

The regeneration by washing was carried out with toluene at a temperature of about 20aC, a flow of 5 mil / min, an atmospheric pressure of about 20 hours. The regeneration by washing seemed to present improved results on the regeneration by calcinations; 10% plus propionitrile and pyrrole was adsorbed onto the washed catalyst.

Table 9 1. - Regeneration of NaY by calcinations (200BC) Regeneration of NaY by washing with toluene room temperature BF- 50% of nC7 and 50% of 1C6 = splashed with 200 ppm of S as thiophene.

Example 9 Competitive Adsorption When 40 ppm of N as but ironi tr i lo were added to the feed of Example 7, it can be seen that the adsorption capacity of pyrrole was reduced. There was a reduction in the adsorption capacity of propioni tri lo as well. It is believed that this was caused by the competition between PN and BN for the active sites of zeoite; however, it seems that the adsorption of the two nitriles prevents the adsorption of pyrrole that occupies the active centers. This becomes evident when the table is compared with table 10. Table 10 shows two identical and identical adsorption.

Table 10 Table 11 shows a summary of the adsorption capacity of sepiolites and zeolite Y in the form of Na, Na-H, H, Cu and Cs, when a base feed containing pyrrole, propionitrile and butyronitrile (determined from above) is used. as being the three most significant poisoning compounds in typical commercial food). Table 11 shows the amounts of N adsorbed when the first compound penetrates.

Table 11 Table 12 shows the values for N that the solids were able to adsorb.

Table 12 From table 12, it is evident that NaY and CuY zeolite are effective adsorbents for non-basic nitrogen compounds. It should be noted that aromatics compete for adsorption sites, and this is more important for pyrrole. The CsY zeolite adsorbed less propionitrile than Nay, but more pyrrole, while the adsorption of butyronitrile was also high. Taking this into account and from tables 12 and 13 above, a mixture of adsorbents could be a pretreatment of non-basic nitrogen compound for the thiophene alkylation process. As mentioned above, regeneration can be achieved and the adsorption capacity can be re-established by heating in an air flow, or by washing with toluene.

Example 10 In this example, the effect of pretreatment of the feed to remove non-basic nitrogen compounds with a commercial alkylation feed of thiophene was demonstrated (see table 4). The commercial thiophene alkylation feed was run in parallel through two fixed beds, one containing Na-Y and the second containing zepiolite. The nitrogen adsorption conditions were 70SF, WHSV = 15 hr "1 with 2 grams of adsorbent material, The product from the adsorbent reactor was collected every 80 minutes, The following feeds were collected. for evaluation in a thiophene alkylation reactor. Commercial feed without pretreatment NaY-1 feed adsorbent Na-Y 0-180 minutes (80 grams) NaY-2 feed Na-Y adsorbent 180-340 minutes (80 grams) NaY-3 adsorbent feed Na-Y 340-510 minutes (80 grams) Feeding NaY-4 adsorbent Na-Y 510-730 minutes (108 grams) Feeding Sep-1 adsorbent Sepiolite 0-180 minutes (80 grams) Feeding Sep-2 adsorbent Sepiolite 510-730 minutes (108 grams) The phosphoric acid catalyst used in the pilot plant runs of the present example was the commercially available catalyst designated as C-84-05 obtained from Süd Chemie Inc. The pilot plant was loaded with 300 mg of a solid phosphoric acid catalyst that was triturated to a Tyler sieve mesh size of 0.4-0.6 itim. The catalyst was dried under nitrogen flow for 2 hours at 2002C before use. The pilot plant consisted of parallel fixed-bed reactors, each capable of containing between 50 to 1,000 mg of catalyst. The design of the pilot plant is similar to that described in example 1 above. The reactors were operated in a downflow operation. Each of the previous feeds was run in this pilot plant sequence. The conditions used for each stream included: LHSV 4.1 hr "1 Pressure 28.1 kg / cm2 gauge Temperature 180 SC The results of this set of experiments are shown in Figure 16. It is evident from the results the strong improvement in catalyst performance achieved for The process of alkylation of thiophene when the commercial feed was pretreated with either NaY or Sepiolite, compared with the rapid deactivation observed with the untreated commercial feed after only 8 hours in current. pretreatment with NaY on the scale evaluated (up to 150 grams of feed processed per gram of adsorbent) It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is that it is clear from the present description of the invention.

Claims (14)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A process for the production of products that are liquid at ambient conditions and contain organic sulfur compounds of higher molecular weight than the corresponding sulfur-containing compounds in the feed stream, characterized in that it comprises: (a) providing a feed stream that comprising a mixture of hydrocarbons including olefins, and sulfur-containing organic compounds as well as organic compounds containing non-basic nitrogen, the feed stream comprises a material boiling between about 60 BC and about 425 SC and having a sulfur content up to about 4,000 or 5,000 parts per million and a nitrogen content of up to about 2000 parts per million; (b) removing the non-basic nitrogen compounds from the feed stream to produce an effluent having a reduced amount of non-basic nitrogen compounds and (c) contacting the effluent with a acid catalyst under conditions that are effective to convert a portion of the impurities to a higher molecular weight sulfur containing material through alkylation by the olefins.

2. The process in accordance with the claim 1, characterized in that the non-basic nitrogen compounds are removed by an adsorption process in which the adsorbent used in the absorption process comprises zeolites having a faujasite structure.

3. The process in accordance with the claim 1, characterized in that the non-basic nitrogen compounds are removed by an adsorption process in which the adsorbent is selected from the group consisting of alkaline faujasites, alkaline earth faujasites, alkaline faujasites partially exchanged with H +, or transition metals of the groups IB , IIB, IVB, VIII, and mixtures thereof, alkaline earth faujasites partially exchanged with H +, or transition metals of groups IB, IIB, IVB, VIII, and mixtures thereof, crystalline magnesium silicates and crystalline magnesium silicates alkaline exchanged.

4. The process in accordance with the claim 2, characterized in that the adsorbent is regenerated with an organic solvent.

5. The process according to claim 4, characterized in that the organic solvent contains a aromatic ring.

6. The process according to claim 5, characterized in that the solvent is selected from the group consisting of benzene and alkylbenzenes having a total number of carbon atoms of eleven or less.

7. The process according to claim 4, characterized in that the solvent is an aliphatic alcohol having twelve or less carbon atoms.

8. The process according to claim 3, characterized in that the adsorbent is a sepiolite in natural form or in the alkaline exchanged form.

9. A process for the polymerization of olefins in an olefin-containing feed stream containing non-basic organic nitrogen compounds, characterized in that it comprises: removing non-basic organic nitrogen compounds by an adsorption process wherein the adsorbent used in The adsorption process comprises zeolites having a faujasite structure and contacting the effluent of the adsorption process with an acid catalyst under conditions that are effective to polymerize the olefins.

10. The process according to claim 9, characterized in that the adsorbent is regenerated with an organic solvent.

11. The process in accordance with the claim 10, characterized in that the organic solvent contains an aromatic ring.

12. The process in accordance with the claim 11, characterized in that the solvent is selected from the group consisting of benzene and alkylbenzenes having a total number of carbon atoms of eleven or less.

13. The process according to claim 10, characterized in that the solvent is an aliphatic alcohol having twelve or fewer carbon atoms.

14. The process according to claim 9, characterized in that the adsorbent is a sepiolite in natural form or in the alkaline exchanged form.