Process for removing CS2 from hydrocarbon streams

Abstract

A process for producing a hydrocarbon stream having a reduced CS2 content, comprising contacting a hydrocarbon stream containing CS2 with a solid reactive CS2-scavenger containing a hydrocarbon residue bearing a primary and / or secondary amino group attached to a solid support at a temperature in the range of 0 to 300°C, and separating the resulting reaction product of CS2 and the reactive CS2-scavenger from the hydrocarbon stream.

Description

[Technical field]

[0001] detail The present invention relates to the use of solid carbon disulfide (CS2)-scavengers for removing CS2 from hydrocarbon streams, to a process for producing hydrocarbon streams having reduced CS2 content, and in particular to the use of certain solid reactive CS2-scavengers and their preparation.

[0002] The feedstocks for steam crackers (naphtha and condensate) contain significant amounts of contaminants such as sulfur and nitrogen components as well as metal species. Over the past few years, the presence of CS2 in particular has become problematic. It has been found that CS2 from contaminated naphtha passes intact through the cracker furnaces and tends to accumulate in the C5+ fraction (pyrolysis gasoline or pygas) after fractionation. In downstream selective hydrogenation of pyrolysis gasoline using Pd or Ni catalysts, CS2 leads to rapid deactivation of the catalyst beds, which requires frequent regeneration and shortens their life. Also, when isoprene is extracted from pygas, CS2 is found in the final product, reducing its value.

[0003] Several processes are known in which a hydrocarbon stream contaminated with CS2 is contacted with an aqueous solution of an amine or polyamine. The CS2 reacts with the amine to form a dithiocarbamate, which is extracted into the aqueous phase and separated from the hydrocarbon stream via phase separation.

[0004] No. 2,418,047 discloses a process for removing carbon disulfide from hydrocarbon liquids by reacting the liquid with dimethylamine in an aqueous solution to form aminodithiocarbamates.

[0005] EP 0053571 A1 discloses the purification of hydrocarbons by treatment with polyamines, for example, tetraethylenepentamine (TEPA) is contacted with a solution of isoprene and pentane containing CS2.

[0006] WO2015 / 026649A1 discloses the use of polyamines as CS2 scavengers in isoprene production. Preferred polyamines are tetraethylenepentamine (TEPA) or diethylenetriamine (DETA). In addition, a quaternary ammonium salt is used as a phase transfer catalyst.

[0007] Although known processes can be efficient in removing CS2, the use of fixed bed processes or solid adsorbents / absorbents is much more convenient and in most cases preferred over extraction processes.

[0008] Removal and Recovery of Carbon Disulfide Emitted by the Viscose Process: Final Report by MJ McIntosh, Energy Systems Division, Argonne National Laboratory, February 1992, discloses results on tests using different substrates reacted with aminosilanes to produce sorbents containing amino groups for the removal of CS2 from water-saturated air. Silica gel or activated alumina was treated with A1120, which appears to be N(beta-aminoethyl) gamma-aminopropyltrimethoxysilane from Silquest.

[0009] These treated adsorbents were found to have no practical value for CS2 recovery from water saturated air containing about 100 ppm CS2 resulting from the viscose process for making rayon or cellulose products. The amine silane treatment was found to provide a significant advantage for CS2 removal when compared to water washed mordenite, which has the most capacity for retaining CS2. However, it was found that the amino treatment appears to improve the ability of activated alumina to retain CS2, while no such difference was noted for silica gel. See sections 4.3.1 and 4.3.2 on page 64 / 65.

[0010] In Energy & Fuels, 1998, 12, 4, 792-797, immobilized chelating agents (e.g., immobilized diethylenetriamine (DETA) attached to silica) have been used for the removal of copper ions from JP-5 jet fuel.

[0011] JP-5 (and JP-8) are both kerosene-grade military jet fuels. According to Shell's technical data sheet for JP-5, the fuel is specifically intended for use on Navy aircraft carriers. For on-board safety reasons, the flash point specification for JP-5 is set at Fp > 60°C, which is considered high.

[0012] According to the literature, kerosene consists of a mixture of hydrocarbons with a boiling range starting at 185°C. Due to the boiling fumes of kerosene type fuels combined with a specification for a high flash point of >60°C, it is unlikely that JP-5 jet fuel would contain CS2 since the boiling point of CS2 is only 46.3°C, which is completely outside the boiling range of kerosene.

[0013] Furthermore, the above mentioned technical data sheet mentions that jet fuels such as JP-5 and 8 are formulated with FSII (fuel system anti-icing agent) and CI / LI (corrosion inhibitor and lubricity improver) additives. In the literature, the corrosion inhibitors in military jet fuel JP-8 (and therefore also JP-5) have been analyzed and the active ingredient of the CI / LI additive was found to be a dimer of linoleic acid. The concentration of the acid was typically found to be 9-24 mg / l. Due to the presence of the acid, adsorption of CS2 cannot occur.

[0014] There are only a few fixed bed processes known on the market that claim to be able to remove CS2 from naphtha. In US2017 / 0073589, CS2 is removed from hydrocarbon streams using clinoptilolite or barium-exchanged zeolite adsorbents.

[0015] WO2018 / 029661A1 relates to a process for reducing the amount of carbon disulfide (CS2) in a hydrocarbon feed containing a C5-C8 fraction. The hydrocarbon feed is treated with an amine-functionalized anion exchange resin (basic anion exchange resin) to obtain a mixture comprising a liquid fraction containing the treated hydrocarbons, a solid mass containing adducts of CS2, and the amine-functionalized anion exchange resin. The liquid fraction thus obtained containing the treated hydrocarbons is separated from the solid mass to obtain hydrocarbons having a CS2 content of less than 2 ppm. The amine-functionalized anion exchange resin can be regenerated from the solid mass. The continuous process is operated at a temperature of <40°C, a pressure of <5 bar, and a typical treatment time of 1 to 10 hours.

[0016] In the case of a fixed bed, the treatment time corresponds to the contact time. WO2018 / 029661 states that the treatment time is 0.1 to 1 h -1 The process is described with treatment times of 1 to 10 hours, corresponding to a linear hourly space velocity (LHSV) of 0.01 mm. The relatively low space velocity is limited by the typical particle size of the available resins (0.3 to 1.2 mm).

[0017] In processes where large volumes of hydrocarbons are treated, typical LHSV values ​​are in the range of 5-10 hr-1 (sometimes even higher) in order to keep the reactor or adsorbent bed size as small as possible. At these high space velocities, the particle size and shape of the adsorbent are critical and need to be optimized.

[0018] The underlying object of the present invention is to provide a solid, preferably fixed bed, adsorbent and process for the selective removal of high capacity CS2 from liquid hydrocarbon streams.

[0019] This object is achieved according to the present invention by a process for producing a hydrocarbon stream having a reduced CS2 content, which comprises contacting a hydrocarbon stream containing CS2 with a solid reactive CS2-scavenger containing a hydrocarbon residue bearing a primary and / or secondary amino group attached to a solid inorganic support at a temperature in the range of 0 to 300°C, preferably 5 to 200°C, more preferably 10 to 100°C, and separating the resulting reaction product of CS2 and the reactive CS2-scavenger from the hydrocarbon stream.

[0020] This object is further realized by the use of the above-mentioned solid CS2-scavenger for removing CS2 from hydrocarbon streams, as well as by a solid reactive CS2-scavenger containing a primary and / or secondary amino group-bearing hydrocarbon residue attached to a solid inorganic support, capable of removing CS2 from hydrocarbon streams and described in more detail below.

[0021] Thus, the present invention also provides linear C attached to a solid support. 3-12 One primary amino group and a linear C at the end of the alkylene residue 3-12 Linear C2-scavenger, preferably N-(3-(trimethoxysilyl)propyl)ethylenediamine, is reacted with silica gel via a solid reactive C2-scavenger containing at least two secondary amino groups inserted in the alkylene residue, and an alkoxysilyl group, preferably a trialkoxysilyl group, to produce linear C2-scavenger. 3-12 A process for its preparation by coupling an alkylene residue to a solid support is disclosed.

[0022] Finally, the present invention discloses the use of this solid reactive CS2-scavenger for removing CS2 from fluids containing CS2, preferably from hydrocarbon fluids or streams.

[0023] According to the present invention, it has been found that CS2 can be selectively removed from steamcracker naphtha without simultaneously removing other sulfur contaminants typically found in the naphtha. This process can be carried out on a naphtha-containing stream, preferably a steamcracker feed stream, or a stream coming from a steamcracker, or in a subsequent extraction and / or distillation unit where the stream is separated into fractions.

[0024] The particle size and shape of the adsorbent can be optimized by selecting the most suitable solid inorganic support and modifying the support with appropriate amine functional groups. -1 , 15h -1 , or 10h -1 Particles of 1.5-10 mm, preferably 1.75-7.5 mm, more preferably 2-5 mm, most preferably 3-5 mm, are particularly suitable for bulk processing, where the particle size can be as high as 1.5-10 mm, preferably 1.75-7.5 mm, more preferably 2-5 mm, most preferably 3-5 mm. Pressure drop problems are not expected. Furthermore, solid inorganic support-based materials can be operated at higher temperatures and pressures and are much less compressible and solvent sensitive compared to resin-based amines.

[0025] The CS2-scavenger used according to the present invention allows higher space velocities when compared to WO2018 / 029661A1, since the particle size can be freely adjusted to achieve the desired higher space velocity. Typical ion exchange resins used according to WO2018 / 029661A1 rely on polymer beads with a diameter typically in the range of 0.3-0.5 mm. Functionalization results in particle swelling so that the final particle diameter is typically in the range of 0.3-1.2 mm. This limited particle size results in high pressure drops in practical applications. Small space velocities of 0.1-1 l / lh and long contact times of 1-10 h result. Depending on the type of solvent, expansion or contraction of the resin particles can occur, which can impede the hydrodynamic flow in the packed bed.

[0026] The CS2-scavengers used according to the invention exhibit thermal, solvent and mechanical stability such that stacking of the adsorbents in fixed beds is possible. Furthermore, they are expansion-free and can be easily regenerated. They can be operated under high feed pressures of 10 bar and above.

[0027] The solid reactive CS2-scavenger used according to the present invention is prepared by immobilizing an amine functional group on a solid support. The term "reactive CS2-scavenger" describes that the amine functional group undergoes a chemical reaction with CS2, which leads to the formation of a carbamate group. Thus, CS2 is not adsorbed or absorbed by the CS2-scavenger in the classical sense, but reacts with it, and is thus covalently bound to it.

[0028] The solid reactive CS2-scavenger can be used to treat liquid hydrocarbons, which can also be described as hydrocarbon streams. The process can be carried out batchwise, for example in a stirred reactor, where a slurry or fluidized solid reactive CS2-scavenger is used, or continuously, preferably by using the solid reactive CS2-scavenger as a fluidized bed or - most preferred - a fixed bed.

[0029] The solid reactive CS2- scavenger can be arranged in the scrubbing zone with packed beds, custom packings, monoliths, and / or trays. It can be arranged, for example, in an absorption column to create a scrubbing zone for a continuous process. Suitable devices are disclosed, for example, in US8,529,857B2.

[0030] The solid support may be in any desired shape, for example in the form of a monolith, such as a honeycomb structure or reactor interior (e.g., made by 3D printing or other additive manufacturing), or in the form of granules, tablets, extrudates, or molded materials. Preferably, the solid support is used in particulate or monolithic form with an average particle size in the range of 0.02-5.0 mm, more preferably 0.1-2.0 mm, most preferably 0.2-0.5 mm. Most preferred particles are spheres or granules with a particle size in the range of 0.1-4 mm. To achieve higher space velocities, particle sizes in the range of 1.5-10 mm, preferably 1.75-7.5 mm, more preferably 2-5 mm, or 3-5 mm, may be preferred. Alternatively, if larger particle sizes are desired, they may be in the range of 5-10 mm, for example, the particle size may be in the range of 6.0-6.5 mm. The average particle size refers to the number or arithmetic mean particle size determined by optical measurement or sieving, sieving or camsizer. Alternatively, photographic techniques can be used to determine number or arithmetic mean particle size, in which a stream of falling or moving particles is analyzed with a digital still or video camera and the particle size is determined from the resulting photograph.

[0031] The solid adsorbent is preferably in particulate form, for example as beads or extruded rods. The adsorbent can be subjected to conventional shaping methods, such as, for example, pelleting, tableting, or extrusion, before its use in the process according to the invention. The solid adsorbent is preferably used in the form of a bed or as a fixed bed.

[0032] The solid support, when used in the process according to the invention, can be selected from a variety of solid materials which preferably exhibit little or no wear. The support must further be chemically inert with respect to the alkylamines and components of the hydrocarbon stream.

[0033] Preferably, the solid supports are selected from silica, alumina, magnesia, titania, zirconia or mixed oxides thereof, or zeolites, aluminosilicates, spinels or carbon, and it is also possible for these supports to be coated with an organic layer.

[0034] More preferably, the solid support is selected from silica gel, alumina, or carbon.

[0035] Suitable solid adsorbents are in particular molecular sieves, carbon-based adsorbents, silica gel or zeolites, also called activated aluminium oxides.

[0036] Preferably, a zeolite having a pore size of at least about 4.6 Å is used. Suitable zeolites are, for example, zeolite A (LTA), zeolite X or Y (FAU faujasite family), or zeolite MFI (ZSM-5 and silicalite). Specific examples are zeolite 5A, zeolite 13X, zeolite 4A, or mixtures thereof.

[0037] Among the A zeolites (LTA), zeolite 4A is particularly suitable, whose sodium ions are preferably partially replaced by calcium. The degree of Na / Ca exchange is preferably between 25 and 85 mol%. Among the zeolites of type X or Y (faujasites FAU), zeolite 13X (NaX) is particularly suitable, other cations such as Ca, Ba, Li, Sr, Mg, Rb, Cs, Cu, Ag can be used for charge balancing. The molar ratio of Si / Al can be from 1 to infinity (such as for example in dealuminated Y zeolites). These ratios are infinity. Among the MFI zeolites, ZSM-5 is suitable having a molar ratio of Si / AI from 1 to infinity (such as for example in silicalites).

[0038] Carbon-based adsorbents include activated carbon, preferably 200-2000 m 2 / g BET surface area (determined by nitrogen physisorption at 77 K).

[0039] In addition, silica gel or activated aluminum oxide is suitable, preferably 100 to 800 ml 2 / g BET surface area.

[0040] The solid reactive CS2-scavenger contains aliphatic hydrocarbon residues bearing primary and / or secondary amino groups attached to a solid support. The residues are preferably attached to the solid support by covalent chemical bonds. A less preferred means for attaching the residues to the solid support is to adsorb them to the surface of the support by ionic, electrostatic, or van der Waals forces.

[0041] Covalent attachment can be achieved through a spacer group that is reactive towards the surface of the solid support, for example, an aliphatic hydrocarbon residue can be coupled to the solid support through an alkoxysilyl group, preferably a trialkoxysilyl group such as a trimethoxysilyl group.

[0042] The spacer group may be an aliphatic, aromatic, araliphatic, or alkaline group. Typically, the spacer is an aliphatic hydrocarbon residue that may contain pendant or inserted aromatic groups, such as phenyl or phenylene groups. Preferably, the aliphatic hydrocarbon residue contains linear, branched, and / or cyclic aliphatic hydrocarbon groups. According to one embodiment of the present invention, the spacer is a pure aliphatic hydrocarbon with an amino group inserted or attached thereto.

[0043] The aliphatic hydrocarbon residues carry at least one primary and / or at least one secondary amino group, preferably at least two amino groups. More preferably, they carry at least three amino groups, preferably at least one primary and at least two secondary amino groups. Most preferably, the aliphatic hydrocarbon residues are linear C 3-12An alkylene residue, particularly a C5-9 alkylene residue, for example a C7 alkylene residue, has one primary amino group at the terminus and at least two secondary amino groups inserted therein.

[0044] Preferably, the solid reactive CS2- scavenger is a solid support selected from silica, alumina and alumina, magnesia, titania, zirconia or mixed oxides thereof, or zeolites, aluminosilicates, spinels, or carbon, in the presence of an aminoalkyltrialkoxysilane, N-[3-(trialkoxysilyl)alkyl]alkylenediamine, or N 1 -(3-(trialkoxysilyl)alkyldialkoxysilanes, preferably the alkoxy is 1-4 Alkoxy is alkyl, and alkylene is C 1-4 It is formed by reacting the alkylene compound with an N-(trialkoxysilylalkyl)alkylenediamine, more preferably an N-(trialkoxysilylalkyl)alkylenediamine, such as N-(3-(trimethoxysilyl)propyl)ethylenediamine.

[0045] The amount of amino groups can be freely selected. Preferably, the solid reactive CS2-scavenger contains 0.1-60 mmol, more preferably 0.2-30 mmol, most preferably 0.5-7.5 mmol of primary and secondary groups / g of aliphatic hydrocarbon residues.

[0046] The amount of primary amino groups is more preferably 0.1 to 20 mmol / g, and even more preferably 0.2 to 10 mmol / g.

[0047] If two secondary amino groups are present per NH2 group, then their amount is twice the above amount of NH2 group content.

[0048] The support on which the amine functional groups are grafted is preferably silica, alumina or carbon. It can be a powder or formed particles, such as spheres, for use in fixed beds. The functional groups are preferably attached to the support by using a silane coupling agent. These products usually contain three hydrolyzable alkoxy groups and one organic substituent containing a primary amine functional group. In most cases, the CS2-scavenger is made by contacting the coupling agent with the support in water. Water is not the only solvent, since methanol or toluene are also possible. The scavenger is then cured, for example at 90 ° C, after filtering and drying the CS2-scavenger. In this way, the surface of the support is covered with amine functional groups that can react with CS2 to form dithiocarbamates.

[0049] The products used in the process of the present invention are described, for example, in a review in Journal of Environmental Chemical Engineering 6 (2018), 3192-3203, where three preferred amine precursors are mentioned several times. The amine precursors for the synthesis of the scavengers according to the present invention are aminopropyltrimethoxysilane, N-[3(trimethoxysilyl)propyl]ethylenediamine, and N 1 -(3-(trimethoxysilyl)-propyl)diethylenetriamine is preferred. Part 2, Chapter 8 of "Characterization and chemical modification of the Silica Surface" by EF Vansant, P. Van Der Voort and KC Vrancken, Vol. 93, Elsevier Science, provides general information on grafting silica surfaces with functional groups including aminosilanes.

[0050] According to one embodiment of the present invention, the solid reactive CS2-scavenger is selected from the scavengers shown in Figure 2. Among the scavengers shown in Figure 2, structures 2 and 3 are preferred. The scavenger shown as structure 2 is most preferred. According to a second embodiment of the present invention, the scavenger is not diethylenetriamine (DETA) attached to silica. Thus, according to one embodiment of the present invention, the scavenger is not structure 3, as shown in Figure 2 herein. According to one embodiment of the present invention, the scavenger is not structure 1 or structure 3, as shown in Figure 2.

[0051] Solid CS2-scavengers as described above are used to remove CS2 from hydrocarbon streams, typically feedstocks for steam crackers such as naphtha or naphtha condensate, or hydrocarbon streams coming from a steam cracker or a subsequent extraction and / or distillation unit.

[0052] Naphtha is the so-called low boiler obtained in mineral oil or crude naphtha distillation immediately after the removal of gases at ambient pressure. It can be straight-run or virgin naphtha, composed mainly of saturated aliphatic hydrocarbons and containing small amounts of aromatics, sulfur, and nitrogen. Like naphtha, straight-run gasoline (SRG), light virgin naphtha (LVN) contains mainly C5 / C6 hydrocarbons, with boiling points typically ranging from 30 to 130 °C. Heavy naphtha, straight-run benzene (SRB), heavy virgin naphtha (HVN) contains C5 / C6 hydrocarbons with boiling points between 130 and 220 °C. 6-12 Contains mostly hydrocarbons.

[0053] There are different forms of naphtha or naphtha-like streams. There can be straight run naphtha, hydrotreated naphtha, light naphtha, (delayed) coker naphtha, FCC naphtha, condensates from certain gas fields (these fields typically carry Hg). For more information on this, see Ullmann's Encyclopedia of Industrial Chemistry, chapter on Ethylene, Section 4 Raw Materials, (vol. 13) 2012, Wiley-VCH, Weinheim. The CS2 problem in the hydrocarbon stream is most pronounced when using coker naphtha. Straight run naphtha or hydrotreated naphtha have a lower degree of this problem. · Naphtha: The first petroleum fraction from the distillation process. Light naphtha: IBP at about 30°C (86°F) and FBP at about 145°C (293°F), contains mostly C6 hydrocarbons. Heavy naphtha: IBP at about 140°C (284°F) and FBP at about 205°C (401°F) contains most of the hydrocarbons with more than 6 carbon atoms. Heavy naphtha is the feedstock for the reformer. · Full-range naphtha: A hydrocarbon stream used as a feedstock in stream crackers with a boiling range of 30-200°C.

[0054] Additionally, cracker naphtha, coker naphtha, non-straight run naphtha, hydrotreated naphtha, and light distillate feedstocks (LDF) may be mentioned as preferred possible hydrocarbons.

[0055] The preferred hydrocarbon streams used in accordance with the present invention have a boiling range of 30° C. to 145° C., which corresponds to light naphtha. Most preferably, the hydrocarbon stream is a C 1-6 It contains hydrocarbons. Therefore, in a preferred embodiment according to the present invention, hydrocarbons having a boiling point above 145° C. are not used. Therefore, typically, jet fuels having a boiling point range of 185° C. to 300° C. are not used.

[0056] The primary objective of this invention is the processing of light naphtha.

[0057] Further, in a preferred embodiment, the hydrocarbon stream does not contain organic acids. Thus, the hydrocarbon stream preferably does not contain carboxylic acids, dicarboxylic acids, or polycarboxylic acids. The presence of organic acids, such as carboxylic acids, dicarboxylic acids, or polycarboxylic acids, in the hydrocarbon stream may inhibit the adsorption of CS2.

[0058] The advantage of the CS2-scavenger of the present invention is that they exhibit remarkable selectivity over other sulfur-containing molecules such as thiols, thiophenes, or sulfides. CS2 is selectively adsorbed to the scavenger, whereas other sulfur-containing molecules are not adsorbed to the CS2-scavenger. This makes the CS2-scavenger ideal for selective adsorption of CS2 from steam cracker naphtha without losing valuable S-capacity due to adsorption of sulfur components other than CS2. Separation of sulfur components other than CS2 is feasible using existing assets, so that they do not accumulate in the C5+ fraction.

[0059] Additionally, hydrocarbon fractions such as isoprene can be used, as mentioned in WO2015 / 026649A1. Suitable hydrocarbon streams are disclosed in US 2,418,047, EP 0053571 A1, WO2015 / 026649A1, US2013 / 0211171 A1, and US8,529,857 B2.

[0060] The steam cracker outlet stream can be, for example, a C1-, C2-, C3-, C4-, C5-, C6-stream.

[0061] The hydrocarbon stream is contacted with the solid reactive CS2-scavenger at a temperature in the range of 10-100°C, preferably 20-80°C, most preferably 30-60°C. The pressure is typically from ambient (1 bar) to 10 bar, more preferably 1-3 bar. The liquid hourly space velocity (LHSV) can be from 1-20 / h, preferably from 2-20 / h, more preferably from 2-15 / h, even more preferably from 3-15 / h, preferably from 3-10 / h, more preferably from 4-10 / h, most preferably from 4-8 / h, or even from 5-10 / h. Higher space velocities are preferred. According to the invention, the contact time is preferably less than 1 hour, more preferably less than 12 minutes, most preferably from 6-12 minutes. Most preferably, the contact time is selected according to the LHSV mentioned above, most preferably corresponding to an LHSV of 5-10 / h.

[0062] The hydrocarbon stream is most preferably naphtha or natural gas condensate or a mixture thereof fed to a steam cracker. The CS2-scavenger can also be used for CS2 removal from pyrolysis gasoline (pygas) or isoprene feedstocks.

[0063] It is possible to regenerate and reuse spent CS2- scavengers by treatment with acids and bases. Both organic or mineral acids and bases can be used.

[0064] The present invention is further illustrated by the following examples. [Brief description of the drawings]

[0065] [Figure 1] FIG. 1 shows CS2 adsorption from heptane. [Diagram 2] FIG. 1 shows an embodiment of a solid reactive CS2 scavenger. [Diagram 3] FIG. 1 shows the adsorption concentration of CS2 in heptane versus operating time. EXAMPLES

[0066] Example 1 The CS2-scavenger used in this example (structure 2 in Figure 2) was prepared according to a modified literature procedure (J. Haz. Mat. 2007, 149, 650-656).

[0067] Silica gel (150.2 g, 0.2-0.5 mm silica gel (60A) from Acros Organics) was mixed with 410 g demi water in a 1 liter round bottom flask. Eight drops of surfactant (Dreft from P&G Professional) were added. 46.3 grams (200 mmol) of N-(3-(trimethoxysilyl)propyl)ethylenediamine were added dropwise while swirling the flask. After addition, the flask was connected to a rotary evaporator and heated to 92 °C for 2 hours while rotating the flask at 60 rpm (no vacuum). The flask was then cooled to room temperature, the aqueous layer was decanted, and the product was washed three times with 200 ml demi water. Finally, the product was filtered and dried in an oven at 105 °C overnight.

[0068] Analysis: LOI(105): 1.0 wt%. CNS: 7.1 wt% carbon, 3.1 wt% nitrogen, <0.05 wt% sulfur.

[0069] The CS2-scavenger thus prepared was tested in a small scale fixed bed reactor. CS2-scavenger particles (2.00 ml = 1.13 g) were premixed with the same amount of inert material (SiC 0.5 mm granules) and charged into the reactor (diameter = 10 mm, L = 50 mm). The bed was dried at 120 °C for 2 h in argon flow (4 ml / min) and finally cooled to the operating temperature (30 °C and 60 °C). A heptane feed containing 60 ppm CS2 (= 50 ppm S) was passed through the bed at 0.2 ml / min (LHSV = 6) and a pressure of 3 barg. Samples from the reactor were taken and analyzed for CS2 content by gas chromatography.

[0070] The adsorption of CS2 from heptane is shown in Figure 1. Figure 1 shows the adsorption of CS2 from heptane at 30 °C and 60 °C over time (LHSV = 6 h -1Figure 1 shows the concentration of CS2 in heptane at the reactor outlet at 200 rpm (1000 rpm and 3 barg). The top curve was measured at 30°C and the bottom curve at 60°C. The data shown in Figure 1 shows that the CS2 sorbent works surprisingly well. After 102 hours on stream, the CS2-scavenger was washed with heptane, dried and analyzed to determine the amounts of carbon, nitrogen and sulfur (see Table 1). [Table 1]

[0071] Example 2 Other CS2-scavengers containing different amine functional groups (structures 1, 3, 4, 5 from Figure 2) were prepared using different amine precursors in a similar manner as described in Example 1. The CS2-scavengers thus prepared were also tested for the removal of CS2 from heptane. The preparation methods and CNS analysis of the spent sorbents are summarized in Table 2.

[0072] Materials depicted in structures 6 and 7 in FIG. 2 can be envisioned to function as CS2-scavengers as well. [Table 2]

[0073] Example 3 In another study, the selectivity of the CS2-scavenger (structure 2 in Figure 2, 1.2 mmol-NH2 / g) over other sulfur-containing molecules was investigated.

[0074] In four different 20 ml flasks, 200 mg of CS2-scavenger was mixed with 10 ml of heptane. To these flasks was then added an 11-fold excess of CS2, ethyl sulfide, thiophene, and propanethiol. The mixture was stirred at ambient temperature and pressure for 18 hours. After filtration and air drying, the spent CS2-scavenger was analyzed for carbon, nitrogen, and sulfur content (see Table 3). [Table 3]

[0075] Example 4 In another test, a scavenger was prepared and tested with spherical silica particles of 1-3 mm (structure 2 in Figure 2, 1.2 mmol-NH2 / g).

[0076] 40.0 g of Perlkat 97-0 silica particles (1-3 mm) were mixed with 109 g of demi water in a 250 milliliter round bottom flask. Four drops of surfactant (Dreft from P&G Professional) were added. 12.3 grams (55 mmol) of N-(3-(trimethoxysilyl)propyl)-ethylenediamine were added dropwise while swirling the flask. After addition, the flask was connected to a rotary evaporator and heated to 92°C for 2 hours while rotating the flask at 60 rpm (no vacuum). The flask was then cooled to room temperature, the aqueous layer was decanted, and the product was washed three times with 100 ml of demi water. Finally, the product was filtered and dried overnight in an oven at 105°C.

[0077] Analysis: LOI(105): 0.2 wt%. CNS: 5.6 wt% carbon, 2.6 wt% nitrogen, <0.05 wt% sulfur.

[0078] The CS2-scavenger was then tested in a fixed bed reactor. A bed of 10 ml of CS2-scavenger particles (10 ml = 5.4 g) prepared as above was premixed with the same amount of inert material (SiC 0.5 mm granules = 17 grams) and charged into a reactor (diameter = 9.1 mm, L = 23.5 cm). A heptane feed containing 60 ppm CS2 (= 50 ppm S) was started above the bed in upflow mode at 0.5 ml / min (LHSV = 3) at ambient temperature and a pressure of 3 barg. Samples from the reactor were taken and analyzed for CS2 content by gas chromatography.

[0079] Figure 3 shows the concentration of CS2 in heptane at the reactor outlet versus on-stream time (10 cc bed, LHSV=3 / h, ambient T, 3 barg). CS2 adsorption from heptane is shown in Figure 3. The data shown in Figure 3 shows that the CS2 adsorbent works surprisingly well at high space velocities even with 1-3 mm spherical silica particles.

[0080] After 140 hours on-stream, the test was stopped. The adsorbent was isolated from the inert material. After air drying, the material was analyzed for CNS.

[0081] Analysis: CNS: 6.5% by weight carbon, 2.6% by weight nitrogen, 1.5% by weight sulfur.

[0082] Example 5 In the test using the CS2-scavenger from Example 4, 200 mg of the scavenger was mixed with 10 ml of heptane. To this mixture, an 11-fold excess of CS2 was added. The mixture was stirred at ambient temperature and pressure for 18 hours. After filtration and air drying, the carbon, nitrogen, and sulfur content of the spent CS2-scavenger was analyzed.

[0083] Analysis: CNS: 6.0 wt% carbon, 2.5 wt% nitrogen, 3.0 wt% sulfur.

Claims

1. C.S. ２ and reacting the resulting hydrocarbon stream with a solid reactive CS containing primary and / or secondary amino group-containing hydrocarbon residues attached to a solid inorganic support at a temperature in the range of 0 to 300° C. ２ - contacting with a scavenger and the resulting CS ２ and reactive CS ２ and separating the reaction product of the solid reactive CS 2 -scavenger from said hydrocarbon stream, wherein said hydrocarbon stream is a naphtha-containing stream, said primary and / or secondary amino group-containing hydrocarbon residue is an aliphatic hydrocarbon residue having at least two amino groups, and said solid reactive CS 2 -scavenger contains 0.1 to 60 mmol, preferably 0.2 to 30 mmol, more preferably 0.5 to 7.5 mmol of primary and secondary amino groups / g. ２ A process for producing a reduced content hydrocarbon stream.

2. 2. The process of claim 1, wherein the naphtha-containing stream is a steamcracker feed stream or a stream coming from a steamcracker or a subsequent extraction and / or distillation unit.

3. The solid reactive CS ２ The process according to claim 1 or 2, wherein the scavenger is used in the form of a slurry, a fluidized bed or a fixed bed.

4. 4. The process according to any one of claims 1 to 3, wherein the solid inorganic support is selected from silica, alumina, magnesia, titania, zirconia or mixed oxides thereof, or zeolites, aluminosilicates, spinels or carbon, which supports can be coated with an organic layer, preferably from silica gel particles.

5. 5. The process according to any one of claims 1 to 4, wherein said hydrocarbon residues each carry at least one primary and / or at least one secondary amino group, preferably at least one terminal primary or secondary amino group.

6. The primary and / or secondary amine groups in the hydrocarbon residue are linear C ２ -C １１ 6. The process of claim 5, wherein said alkylene residues are separated from each other by alkylene residues.

7. Linear C ３－２０ One primary amino group at the end of the alkylene residue and a linear C ３－２０ At least one secondary amino group inserted in an alkylene residue is attached to the solid support, and / or at least one tertiary amino group and / or secondary amino group is attached to the solid support. ５－２０ The process of claim 5, wherein the alkylene residue is inserted.

8. The solid reactive CS ２ A process according to any one of claims 1 to 7, wherein the scavenger is formed by reacting a solid support selected from silica, alumina, magnesia, titania, zirconia or mixed oxides thereof, or zeolites, aluminosilicates, spinels or carbon, with a N-(trialkoxysilylalkyl)alkylenediamine, preferably N-(3-(trimethoxysilyl)propyl)ethylenediamine.

9. CS from Hydrocarbon Streams ２ The solid CS according to any one of claims 1 to 8 for removing ２ - Use of scavengers.

10. Solid reactive CS containing primary and / or secondary amino group-containing hydrocarbon residues attached to a solid inorganic support ２ - a scavenger, The solid reactive CS ２ - a solid support in which the scavenger is selected from silica, alumina, magnesia, titania, zirconia, or mixed oxides thereof, or zeolites, aluminosilicates, spinels, or carbon, is reacted with an N-[3-(trialkoxysilyl)alkyl]alkylenediamine or a N １ -(3-(trialkoxysilyl)alkyldialkylenetriamine, preferably N-[3-(trialkoxysilyl)alkyl]alkylenediamine, wherein the solid reactive CS 2 -scavenger contains 0.1 to 60 mmol, preferably 0.2 to 30 mmol, more preferably 0.5 to 7.5 mmol of primary and secondary amino groups / g. ２ - Scavenger.

11. The scavenger of claim 10, wherein the solid inorganic support is coated with an organic layer, preferably from silica gel particles.

12. C.S. ２ and reacting the resulting hydrocarbon stream with a solid reactive CS containing primary and / or secondary amino group-containing hydrocarbon residues attached to a solid inorganic support at a temperature in the range of 0 to 300° C. ２ - contacting with a scavenger and the resulting CS ２ and reactive CS ２ - separating the reaction product with the scavenger from the hydrocarbon stream, wherein the hydrocarbon stream is a naphtha-containing stream, the primary and / or secondary amino group-containing hydrocarbon residue is an aliphatic hydrocarbon residue having at least two amino groups, and the aliphatic hydrocarbon residue is coupled to the solid support through an alkoxysilyl group, preferably a trialkoxysilyl group, or through a hydroxysilyl group. ２ A process for producing a reduced content hydrocarbon stream.

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