KR20180042849A - Composition, method and application thereof - Google Patents

Abstract

The present invention relates to a composition comprising potassium carbonate and calcium acetate optionally together with a sulfur containing compound. The compositions of the present invention reduce coke formation during hydrocarbon cracking and reduce surface cokes and crushed cokes during hydrocarbon cracking, especially compared to hydrocarbon cracking without such compositions. The invention also relates to a method for reducing the formation and / or deposition of coke during pyrolysis or decomposition of hydrocarbons.

Description

Composition, method and application thereof

The present invention relates to the field of organic chemistry, in particular to the steam cracking of hydrocarbons. The present invention relates to compositions comprising inorganic salts, including, but not limited to, Group 1A and Group 2A metal salts, respectively. The compositions of the present invention are used to reduce the formation and / or deposition of coke in systems used for high temperature treatment or decomposition of hydrocarbons. The present invention also relates to the addition of a composition comprising an inorganic salt, including, but not limited to, Group 1A and Group 2A metal salts to a system used for the decomposition of hydrocarbons. Accordingly, the present invention provides a composition comprising a metal salt such as potassium carbonate and calcium acetate and a method of using the same to reduce coke formation and / or deposition during decomposition of hydrocarbons. The present invention also illustrates a system in which the methods and compositions are used for the reduction of coke.

Steam cracking of hydrocarbons into olefins such as ethylene and propylene is an important process in the petrochemical industry. Hydrocarbons such as ethane, propane, butane, mixtures thereof and naphtha are decomposed into olefins in tubular reactors in the presence of steam at high temperatures of 800-855 ° C.

A unique problem associated with the constituent material (MOC) of the inner surface of the reactor / cracker coil unit is the tendency to promote coke formation because side reactions due to pyrolysis lead to undesirable products. The coke is deposited as a layer on the inner wall of the reactor coil and on the transfer line exchanger (TLE) used to recover heat from the product stream. The amount of coke deposited on the coil surface depends on the rigor of operations such as feedstock composition, operating temperature and vapor dilution ratio, coil design and metallurgy of the metal used to construct the reactor unit. Accumulation of coke decreases the coil diameter, thereby increasing the pressure drop and reducing the amount of heat transfer, and therefore the temperature of the outer tube metal must increase with the passage of time.

Coke formation is the result of complex or complex mechanisms involving catalytic reactions, radical reactions and condensation reactions. Catalyst mechanisms have potential catalytic activity and require metal species such as iron (Fe), nickel (Ni) and chromium (Cr) to be used on the inner surface of the reactor / cracking coil device. The filament coke is formed into a metal agglomerate at the tip end of the device. These coke filaments are good collecting sites for coke formed by various mechanisms including free radical mechanisms and condensation mechanisms. Free radical mechanisms require the reaction of micro-species, mainly gas-free radicals, along with the giant radicals present on the surface of the coke, whereas condensation mechanisms are non-catalytic mechanisms and occur on metal surfaces or coke surfaces. The heavy polynuclear compounds present in the tar and soot are condensed at the reactor inner wall and at the dehydrogenated gas interface to contribute to the deposition of coke on the inner wall of the reactor apparatus.

Periodic interruption of the apparatus is necessary to burn the coke by removing the coke using steam and air at a temperature of about 870 ° C. This coke removal is required once every 30 to 90 days, depending on the mode of operation and the composition of the feedstock. As a result, during the coke removal process, the production of ethylene and other industrial products is stopped for a considerable time, and often also the coke removal deteriorates the coil metal in the reactor. The main challenge encountered in steam cracking is the reduction of coke deposition in the radiation section and the transmission line exchanger (TLE). Thus, efforts are needed to eliminate or at least reduce coke formation and increase the operating length between two coke rinses.

1. To overcome the detrimental effects of coke build-up on the reactor surface, including metallurgical deformation, 2. surface pretreatment, 3. increased vapor dilution ratio, 4. improved control of operating conditions and 5. improved raw material quality. Method has been announced.

Despite previous efforts, there is still a need for commercially viable compositions and methods for reducing coke deposition (surface coke) and cracked coke formation on the reactor walls during pyrolysis of hydrocarbons to produce light olefins Do. However, the present invention overcomes the above-mentioned disadvantages through the aspects described below.

The present invention relates to a composition comprising an alkali metal salt and an alkali metal salt optionally together with a sulfur-containing compound, wherein the composition reduces coke formation during hydrocarbon decomposition.

The compositions of the present invention also reduce coke formation by the memory effect of the composition during hydrocarbon decomposition, and the memory effect of the composition is maintained for at least two cycles of hydrocarbon decomposition.

The present invention also relates to a method of reducing coke formation during hydrocarbon cracking comprising the step of injecting a composition comprising potassium carbonate and calcium acetate optionally together with a sulfur containing compound into a reactor system and hydrolyzing the reactor system .

Are included in the scope of the present invention.

Reference will now be made, by way of example only to the embodiments illustrated in the accompanying drawings, in which the present invention may be readily understood and may be practiced. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and form a part of the specification, serve to further illustrate embodiments and serve to explain various principles and advantages of the invention.
Figure 1 is a schematic diagram of a pyrolysis process of hydrocarbons and an experimental set-up (pyrolysis device) for converting it to olefins.
Figure 2 is a bar graph showing the amount of surface coke formed during hydrocarbon decomposition in the absence (R-405 and R-408) and presence (R-412) compositions of the present invention. The figure also establishes the sustainable effect of the elements of the composition after the primary operation in the form of memory operations M1 and M2 (R-413 and R-414), respectively, and demonstrates the memory effect of the composition.
3 is a bar graph showing the amount of surface coke formed during hydrocarbon decomposition in the absence (R-408) and presence (R-412) compositions of the present invention. The figure also establishes the sustainable effect of the elements of the composition after the primary operation in the form of memory operations M1 and M2 (R-413 and R-414), respectively, and demonstrates the memory effect of the composition.
Figure 4 is a bar graph showing the amount of broken coke formed during hydrocarbon decomposition in the absence (R-408) and presence (R-412) compositions of the present invention. The figure also establishes the sustainable effect of the elements of the composition after the primary operation in the form of memory operations M1 and M2 (R-413 and R-414), respectively, and demonstrates the memory effect of the composition.
Figure 5 is a bar graph showing the percentage of product yield obtained during hydrocarbon decomposition in the absence (R-408) and presence (R-412) of the composition of the present invention.
Figure 6 is a bar graph showing the amount of metal leaching recorded by inductively coupled plasma (ICP) analysis during hydrocracking at the absence (R-408) and presence (R-412) of the composition of the present invention. The figure also establishes the sustainable effect of the elements of the composition after the primary operation in the form of memory operations M1 and M2 (R-413 and R-414), respectively, and demonstrates the memory effect of the composition.
Figure 7 is a bar graph showing the amount of metal content observed during hydrocarbon decomposition in the absence (R-408) and presence (R-412) compositions of the present invention and demonstrates reduced metal leaching by the composition. The figure also establishes the sustainable effect of the elements of the composition after the primary operation in the form of memory operations M1 and M2 (R-413 and R-414), respectively, and demonstrates the memory effect of the composition.

As mentioned in the Background section, in order to overcome the non-limiting disadvantages, the present invention relates to commercially available and inexpensive compositions, methods and compositions for reducing coke formation and / or coke deposition in a reactor system during decomposition of hydrocarbons Application of the composition.

The present invention relates to a composition comprising a plurality of inorganic salts optionally together with a sulfur-containing compound.

In one embodiment, the inorganic salt in the composition is a metal salt having the same or different cations and anion moieties, and the cation moiety comprises cations of the group of the periodic table, including but not limited to groups IA and IIA.

In one embodiment, the cation moiety of the composition includes, but is not limited to, Group IA metals or beryllium, magnesium, calcium, strontium, barium and radium, including, but not limited to lithium, sodium, potassium, rubidium, cesium and francium. Gt; IIA < / RTI > metal or any combination thereof.

In one exemplary embodiment, the anion moieties of the composition include anions including, but not limited to, acetate, fumarate, formate, maleate, oxalate, carbonate, bicarbonate, sulfate, disulfate, .

In a preferred embodiment, the Group IA metal salt of the composition is potassium carbonate.

In another preferred embodiment, the Group 2A metal salt in the composition is calcium acetate.

In one exemplary embodiment, the sulfur containing compound in the composition is selected from the group consisting of dimethyl disulfide (DMDS), dimethyl sulfide (DMS), diethyl sulfide (DES), diethyl disulfide (DEDS), carbon disulfide, But are not limited to, mixtures of sulfoxides and sulfides.

In one embodiment, the concentration of potassium carbonate and calcium acetate in the composition ranges from about lpppmw to 100 ppmw, preferably from about 1 ppmw to 10 ppmw, and more preferably from about 1 ppmw to 4 ppmw, To 40% by weight, and the calcium acetate is about 60% to 70% by weight.

In one preferred embodiment, the concentration of potassium carbonate and calcium acetate in the composition ranges from about 1 ppmw to 10 ppmw, with potassium carbonate at about 35% by weight and calcium acetate at about 65% by weight at this concentration.

In another preferred embodiment, the concentration of potassium carbonate and calcium acetate in the composition ranges from about 1 ppmw to 4 ppmw, with potassium carbonate at about 35 wt% and calcium acetate at about 65 wt% at this concentration.

In one embodiment, the sulfur-containing compound in the carbohydrate source ranges from about 50 ppmw to 250 ppmw.

In another embodiment, the sulfur is part of the cracking process and the sulfur-containing compound is injected as a liquid into the cracking process together with the composition of the present invention. The sulfur-containing compound includes, but is not limited to, dimethyl disulfide and other disulfide directly injected into the digestor with the composition of the present invention.

In one embodiment, the compositions of the present invention are soluble in a solvent, including, but not limited to, polar and nonpolar solvents.

In one exemplary embodiment, the potassium carbonate and calcium acetate of the composition are soluble in water or a polar solvent.

Compositions comprising potassium carbonate and calcium acetate optionally in combination with the sulfur containing compounds of the present invention reduce coke formation and / or deposition of coke in the reactor system.

In one exemplary embodiment, the composition of the present invention reduces the formation of coke in the reactor system by at least 40%.

In another exemplary embodiment, the compositions of the present invention reduce the formation of coke in the reactor system by at least 60%.

In one embodiment, the composition of the present invention reduces coke formation in the reactor system by at least 40% during the cracking process compared to the process at the time of the absence of the composition.

In another embodiment, the composition of the present invention reduces the formation of surface coke by at least 60% during the cracking process compared to the process at the time of the absence of the composition.

In another embodiment, the compositions of the present invention reduce the cracked coke in the reactor system by at least 25% during the cracking process compared to the process at the time of the absence of the composition.

In another embodiment, the compositions of the present invention demonstrate a memory effect, wherein such compositions reduce at least 50% of the formation of surface coke in the reactor system during the cracking process and reduce the cracked coke by at least 25%.

The memory effect represents the composition of the present invention remaining after a coke removal cycle that can reduce coke formation in subsequent fission cycles. For example, the composition of the present invention added during the first cycle of degradation reduces coke formation for at least two cycles in a subsequent cycle and does not need to add the composition to the subsequent cycle of degradation.

In one embodiment, the memory effect of the composition is retained and effective for at least two cycles of the degradation process in the reactor system.

In another embodiment, the composition of the present invention in the reactor system during the cracking process reduces corrosion by at least 40% compared to the process at the time of the absence of the composition.

In another further embodiment, the composition of the present invention in a reactor system during the cracking process reduces at least 50% metal leaching compared to the process at the time of the absence of the composition.

In one embodiment, the compositions of the present invention reduce coke formation in the reactor system, and such reactor systems include, but are not limited to, decomposition reactor apparatus used for pyrolysis of hydrocarbons.

The present invention relates to a method for reducing coke formation and / or coke optimum during hydrocarbon cracking, the method comprising injecting the composition of the present invention into a reactor system.

In one embodiment, the reactor system includes, but is not limited to, a decomposition reactor apparatus used for the decomposition of hydrocarbons.

In one preferred embodiment, the present invention relates to a method of using the composition of the present invention to reduce the formation of coke and / or the deposition of coke in a reactor system, which reactor system comprises a decomposition reactor Including but not limited to devices. The method comprises the step of injecting the composition of the present invention into the reactor system, which optionally comprises potassium carbonate and calcium acetate together with a sulfur-containing compound.

In one non-limiting embodiment, a method for reducing the formation of coke and / or deposition of coke in a reactor system during decomposition of hydrocarbons comprises the following steps:

a) injecting the composition of the present invention into a reactor system together with water or a hydrocarbon feedstock or both; And

b) exposing the reactor system to a high temperature and allowing decomposition of the hydrocarbon injected into the reactor system in the presence of the composition, wherein during the formation of the coke and / or deposition of the coke in the reactor system, Is found to be substantially reduced compared to the process.

In a non-limiting embodiment, the addition of the composition into the reactor system during decomposition reduces the formation of surface coke in the reactor apparatus, reduces the formation of crushed coke, and / , Reduces the deposition of coke on the carrier line and the inner walls of the cracking tubes, thereby increasing the operating length of the reactor and reducing the need for frequent coke removal of the reactor.

In one non-limiting embodiment, the process of the present invention employing the composition of the present invention results in at least a 40% reduction in coke formation and / or deposition of coke during decomposition of the hydrocarbons compared to decomposition of the hydrocarbon without the composition.

In one non-limiting embodiment, the process of the present invention employing the composition of the present invention results in at least a 60% reduction in coke formation and / or deposition of coke during decomposition of the hydrocarbons compared to decomposition of the hydrocarbon without the composition.

In another non-limiting embodiment, the process of the present invention using the composition of the present invention results in at least a 60% reduction in surface coke during decomposition of the hydrocarbons as compared to the decomposition of hydrocarbons without this composition.

In another non-limiting embodiment, the process of the present invention employing the composition of the present invention results in at least a 25% reduction in crushed coke during decomposition of the hydrocarbons as compared to the decomposition of hydrocarbons without the composition.

In another non-limiting embodiment, during the method of the present invention, the compositions of the present invention demonstrate a memory effect, and such a method with a memory effect of the composition can provide at least 50% of the surface coke during hydrocarbon decomposition, Resulting in at least a 25% reduction in crushed coke.

In one non-limiting embodiment, in the process of the present invention, the compositions of the present invention may be used in conjunction with water used for the production of steam, or with vapors generated directly, or with hydrocarbon or hydrocarbon feedstocks, Are injected together into the reactor system.

In one preferred embodiment, in the process of the present invention, the composition is injected into the reactor system with steam.

In another preferred embodiment, in the process of the present invention, the composition is injected into the reactor system together with a hydrocarbon or hydrocarbon feedstock.

In one non-limiting embodiment, the hydrocarbon or hydrocarbon feedstock loaded into the reactor system includes, but is not limited to, compounds such as naphtha. In one preferred embodiment, the naphtha used as the hydrocarbon feedstock includes, but is not limited to, light naphtha and heavy naphtha, preferably light naphtha.

In one non-limiting embodiment, the inventive method of using the compositions of the present invention to reduce the formation of coke and / or reduce the deposition of coke in the reactor system can be carried out by any of the conventionally known methods for the decomposition of hydrocarbons Lt; / RTI > reactor or system. Such a reactor or system can perform decomposition of hydrocarbons by performing a series of steps well-established and understood by those skilled in the art. However, for the reduction of coke formation and / or the reduction of deposition of coke, the composition of the present invention must be integrated with the decomposition step of the hydrocarbons.

In one exemplary embodiment, the method of reducing the formation of coke and / or the deposition of coke during decomposition of hydrocarbons requires the following action:

Initially, the furnace is turned on and nitrogen or air is continuously supplied at a rate of about 80 to 100 占 폚 / h while the temperature is gradually increased from room temperature. After a cross-over temperature of about 450 [deg.] C to 500 [deg.] C and a desired temperature profile of about 800 [deg.] C to 830 [deg.] C of coil outlet temperature is established in the reactor, the composition of the present invention is injected into the reactor apparatus with water. After about 30 minutes, the feed nitrogen or air is stopped and the hydrocarbon feed (naphtha) is fed to the reactor unit. The flow rates of naphtha and water are set to maintain a desired dilution ratio of about 0.3 to 0.5 throughout the process. As the naphtha is injected into the reactor due to the endothermic reaction occurring in the reactor apparatus, the temperature of the furnace is lowered to about 20 캜. The temperature is then gradually increased to a desired temperature profile of about 450 [deg.] C to 500 [deg.] C crossover temperature and a coil outlet temperature of about 810 [deg.] C to 850 [deg.] C. The product gas resulting from the reaction is analyzed using two gas chromatographs. The product gas includes but is not limited to hydrogen, methane, ethane, ethylene, propane, propylene, butane, butene, 1,2-butadiene, 1,3-butadiene and pentane. The mass of naphtha and water is taken, the amount of liquid product collected is weighed, the total amount of gas is metered through the gas flow meter during the period, and the product gas thus formed is analyzed to determine the mass retention do. During the reaction (decomposition operation), the product gas is analyzed once after about 12 hours. After completion of the operation, the reactor is cooled to room temperature of about 20 ° C to 40 ° C and the weight of the thermowell of the reactor is measured to estimate the amount of reduced surface coke during the reaction, and the formation of the coke is reduced by at least 60%. Similarly, the crushed coke is collected at the end of the operation to cool the coke to room temperature to about 20 ° C to 40 ° C and to open the furnace and then estimate the amount of reduced crushed coke during the reaction, wherein the crushed coke is at least 25%, after which the thermowell is immobilized to the reactor and a leak test is performed.

In another exemplary embodiment, the method of reducing the formation of coke and / or the deposition of coke during decomposition of hydrocarbons requires the following actions: Initially, the furnace is turned on and nitrogen or air is continuously supplied, Slowly increase. After a cross-over temperature of about 450 [deg.] C to 500 [deg.] C and a desired temperature profile of about 800 [deg.] C to 830 [deg.] C of the coil exit temperature is established in the reactor, water is injected into the reactor apparatus. After about 30 minutes, the feed nitrogen or air is stopped and the hydrocarbon feed (naphtha) is fed to the reactor unit. The flow rate of the naphtha with the composition of the present invention and water is set to maintain a desired dilution ratio of about 0.3 to 0.5 throughout the process. Due to the endothermic reaction occurring in the reactor apparatus, the temperature of the furnace is lowered to about 20 캜 as soon as the naphtha is injected into the reactor together with the composition of the present invention. The temperature is then gradually increased to a desired temperature profile of about 450 [deg.] C to 500 [deg.] C crossover temperature and a coil outlet temperature of about 810 [deg.] C to 850 [deg.] C. The product gas resulting from the reaction is analyzed using two gas chromatographs. The mass of naphtha and water is taken, the amount of liquid product collected is weighed, the total amount of gas is metered through the gas flow meter during the period, and the product gas thus formed is analyzed to determine the mass retention do. During the reaction (decomposition operation), the product gas is analyzed once after about 12 hours. After completion of the operation, the reactor is cooled to room temperature of about 20 ° C to 40 ° C and the weight of the thermowell of the reactor is measured to estimate the amount of reduced surface coke during the reaction, and the formation of the coke is reduced by at least 60%. Similarly, the crushed coke is collected at the end of operation to cool to about 20 ° C to 40 ° C to room temperature and to open the furnace and then estimate the amount of reduced crushed coke during the reaction, wherein the crushed coke is at least 25%, after which the thermowell is immobilized to the reactor and a leak test is performed. In one non-limiting embodiment, the process of the present invention employing the compositions of the present invention requires decomposition of the hydrocarbons at a high temperature in the range of about 800 ° C to 850 ° C, preferably about 825 ° C.

In one non-limiting embodiment, in the method of the present invention, the inventive process for reducing the formation of crushed coke and the formation of surface coke within the reactor system and / or reducing the deposition of coke on the inner wall of the reactor system The composition comprises potassium carbonate and calcium acetate at a concentration in the range of about lpppmw to 100 ppmw at which the potassium carbonate is from about 30% to 40% by weight and the calcium acetate from about 60% to 70% by weight, based on the hydrocarbon, The sulfur-containing compound has a concentration of about 50 ppmw to 250 ppmw.

In one preferred embodiment, in the process of the present invention, the composition of the present invention used to reduce the formation of crushed coke and the formation of surface coke within the reactor system and / or to reduce the deposition of coke on the inner wall of the reactor system At a concentration ranging from about lpppmw to 10 ppmw of potassium carbonate and calcium acetate at a concentration of about 35 wt% potassium carbonate, about 65 wt% calcium carbonate, and about 50 ppmw up to 250 ppm wt Concentration.

In another preferred embodiment, the compositions of the present invention used in the process of the present invention to reduce the formation of crushed coke and the formation of surface coke within the reactor system and / or to reduce the deposition of coke on the inner wall of the reactor system Potassium carbonate and calcium acetate at a concentration ranging from about lpppmw to 10 ppmw, wherein, for the hydrocarbons, potassium carbonate is about 35 wt%, calcium acetate is about 65 wt%, and the sulfur containing compound is in the range of about 50 ppmw to 250 ppmw Concentration.

In a non-limiting embodiment, the metal salt of the composition is decomposed to an oxide during the hydrocracking process at a pyrolysis temperature of about 810 캜 to 855 캜, which interacts with the coke formed or deposited in the reactor system and catalyzes the coke gasification reaction Thereby reducing total coke formation.

In another exemplary embodiment, the potassium carbonate of the composition is decomposed to potassium oxide during the hydrocracking process at a pyrolysis temperature of about 810 캜 to 855 캜, the potassium oxide interacts with the coke formed or deposited in the reactor system, Catalyzes the reaction to reduce total coke formation.

In another exemplary embodiment, the calcium acetate of the composition decomposes to potassium oxide during the hydrocracking process at a pyrolysis temperature of about 810 DEG C to 855 DEG C, and the calcium oxide interacts with the coke formed or deposited in the reactor system, Catalyzes the reaction to reduce total coke formation.

In another exemplary embodiment, the sulfur-containing compound in the composition modulates excess carbon oxides formed during coke gasification. Thus synergistically interacting with potassium carbonate and calcium acetate of compositions which reduce coke formation.

In one embodiment, the sulfur content in the feedstock and / or composition used in the reaction should be sufficient to control the excess of carbon oxides formed during the coke gasification. In one non-limiting embodiment, the relative amount of composition is adjusted to maintain the coke reduction and reduce the level of corrosion. The concentration of each element in the composition is less than 1 ppmw to meet specifications for fouling and corrosion. For example, ppmw of the composition consists of 65% calcium acetate and 35% potassium carbonate, i.e., about 2.6 ppmw of calcium acetate and about 1.4 ppmw of potassium carbonate. The calcium element concentration in calcium acetate is about 25%, which corresponds to about 0.65 ppmw calcium, and the potassium element concentration in potassium carbonate is about 56.58%, which corresponds to about 0.792 ppmw. Thus, the concentration of each element in the composition is significantly lower than the 1 ppmw limit to minimize corrosion.

In one exemplary embodiment, a method of reducing the formation of coke and / or deposition of coke during the cracking process of hydrocarbons as described above is carried out in a cracking system (reactor system) as provided by FIG. 1 of the present invention. Figure 1 shows a hydrocarbon feedstock comprising a naphtha vaporizer, a water vaporizer, a mixer, a cracker furnace, a naphtha tank, a naphtha feed pump, a water feed tank, a water feed pump, transfer line heat exchangers (TLEs) 1 and 2, and a gas- Naphtha), in which all the furnaces used in the system are electrically heated.

In one exemplary embodiment, in the pyrolysis system illustrated in the present invention, water comprising naphtha (raw material) 10 and inventive composition 12 is stored in two SS tanks at atmospheric pressure. The tank is provided with a level gauge capable of regularly checking the flow rate of water containing naphtha and the composition of the present invention. Two tanks are installed on two separate electronic scales 14 and 16 to measure the amount of water containing the raw material and the composition consumed in a particular operation. In another embodiment, there are two metering pumps 18 and 20 of a predetermined capacity for pumping water comprising hydrocarbon naphtha raw materials and compositions, respectively, comprising the composition. Inhalation occurs in the storage tank through a spiral tube to minimize pulsation of the feed stream. The system also includes two vaporizers, a naphtha vaporizer 22 made of SS 316 and a water vaporizer 24. The furnace is heated to vaporize the naphtha and water, along with the composition of the present invention where heat is supplied electrically and optionally pumped from the metering pump. During normal operation, the effluent of the vaporizer is sent to the mixer 26, where the temperature is raised to a range of about 400 ° C to 600 ° C, preferably about 480 ° C, referred to as crossover temperature. The reactor coil 36 is a straight tube made of 11 mm inner diameter, 3.01 mm thick, including a 35 mm incoloy 800 tube, and has a temperature profile measurement. The thermowell is fixed from the bottom of the reactor tube, which is made of SS-316, 260 mm long and 6.35 mm outer diameter, and serves as a concentric insert. The coil is fixed to a single electric furnace 38 of 360 mm length and 255 mm width in a single area. To a desired temperature profile of about 450 [deg.] C to 855 [deg.] C at the coil from the inlet to the outlet. The thermocouple is located inside the reactor coil and moves the position to measure the process gas temperature profile. The outer wall temperature of the furnace is measured at the center position. The gas from the furnace is quenched to about 600 ° C. The naphtha feed flow rate can vary up to 100 g / h. The gas is further cooled in two serially connected transfer line heat exchangers (TLE 44 and 46) to selectively condense the vapor containing heavy materials (heaviers) in the composition of the present invention and the cracked product mixture. The condensed water and liquid are collected from the gas liquid separator 48 and metered for mass balance calculations. The non-condensed gas is further cooled and measured with a wet gas meter (50). The gas mixture is sent for analysis by the CO / CO2 analyzer 52, two gas chromatographs 54 and 56, and the output of the GC is sent to the personal computer for area integration and processing.

In one further embodiment, the decomposed gas samples discharged after the process are simultaneously analyzed by two gas chromatography (GC) systems. Hydrogen and methine are detected by a thermal conductivity detector (TCD) in the first GC system (HP 3362), while all hydrocarbons present in the gas mixture are analyzed by a second GC (HP 5890) using a flame ionization detector. Peak identification and integration is performed by a commercial integrated package, and through this identification, the product distribution can be determined from a weight percentage perspective. Since the feed flow rate is known, the yield of product wt% / wt of hydrocarbon feedstock and material resin can be calculated.

Additional embodiments and features of the invention will be apparent to those skilled in the art based on the description provided herein. The embodiments provided in the present invention provide various features and advantages in the detailed description. The description of known / conventional methods and techniques is omitted so as not to unnecessarily obscure the embodiments of the present invention. The present invention also provides an embodiment for explaining the above embodiments, and certain embodiments have been employed to illustrate embodiments of the present invention. For the purposes of this disclosure, the embodiments used in the present invention are intended only to facilitate an understanding of the manner in which the present embodiments may be practiced and to enable those skilled in the art to practice the present invention. Accordingly, the following examples should not be construed as limiting the scope of embodiments of the present invention.

Example

Example 1: Decomposition of hydrocarbons with water as a vapor without using the composition of the present invention (control operation)

The test run (R-405) is carried out on a bench scale cracker with a cracker coil made of Incoloy 800HT and using naphtha as the raw material. The coil outlet temperature is maintained at a temperature of about 825 DEG C and the vapor dilution is maintained at a ratio of about 0.32. The corresponding residence time is about 0.5 seconds. The raw olefin content was found to be about 1.94%. Blank operation is carried out using distilled water for about 48 hours. The surface coke deposited on the surface of the thermowell is recorded as 0.26 g at the end of the 48 hour operation when the furnace is opened after cooling. Reproducibility of operation is tested by repeating operation under the same conditions.

Example 2 Hydrocarbon Decomposition with Plant Steam Condensate as Water Without Using the Composition of the Invention (Control Operation)

Experimental operation (R-408) is carried out under the same conditions as the blank operation described in Example 1, except that the plant steam condensate obtained from quench water consisting of caustic (NaOH) is added to pH control instead of water. The blank operation was carried out for about 48 hours and the surface coke deposited in the presence of caustic was found to be in the same range of about 0.293 g of base operation (Example 1). The amount of crushed coke from the reactor was found to be 13.28 g. This data is considered a benchmark when evaluating compositions of the present invention for coke reduction estimates.

Example 3: Hydrolysis in the presence of the composition of the present invention

(R-412) under the same conditions as the blank operation described in Example 1, and the composition of the present invention with the plant vapor condensate is injected into the plant vapor condensate at a concentration of about 4 ppmw, Where the calcium acetate is about 65 weight percent and the potassium carbonate is about 35 weight percent. The concentration of the composition is maintained at 4 ppmw throughout the 48 hour run of the experiment. The amount of surface coke formed during the reaction was much less than that in Examples 1 and 2 above and was found to be 0.115 g as disclosed in FIG. The amount of surface coke formed during the reaction involving the composition of the present invention is performed in Example 2 and is reduced by about 60% as compared to the benchmark based operation as described in FIG. The amount of crushed coke is reduced by about 35% as compared to the benchmark base operation performed in Example 35, as described in FIG. As described in Figures 5 and 6, further addition of the compositions of the present invention also did not show any adverse effect on product yield. The components of the final product obtained after the base operation of Example 2 (without the composition) and in this experiment (with the composition) are very similar in quantity and quality. In addition, inductively coupled plasma (ICP) analysis of the formed coke and liquid samples did not show evidence of corrosion, indicating that the compositions of the present invention did not cause corrosion

Example 4: Memory effect of the composition of the present invention (Test 1).

Experimental operation (R-413) was performed to test the effect of the residue element (memory effect) of the composition used in Example 3 in the reactor system. Thus, in the same reactor, this experimental run is performed under the same conditions as the blank run described in Example 2, that is, to test the memory effect of the elements of the composition of the present invention left in the reactor system after one cycle of the cracking process There is no addition of the composition of the present invention through the vapor condensate. After completion of operation, the surface coke was found to be 0.145 g, which is about 50.6% reduction of the surface coke compared to the coke formed in the blank operation of Example 2. Also, the crushed coke was found to be 9.95 g, which is about 25% reduction of the crushed coke compared to the crushed coke formed in the blank operation of Example 2. The reduction in surface cokes and crushed cokes in this example is due to the presence of the residual elements of the composition of the present invention used in Example 3. This memory operation is denoted by M1 and the results are given in Figs.

Example 5: Memory effect of the composition of the present invention (Test 2).

Experimental run (R-414) was performed to further test the memory effect of the residual elements of the composition of the present invention left in the reactor after Test 1 of Example 4. [ This experimental operation is performed under the same condition as the first memory operation as described in the fourth embodiment. The amount of surface coke formed at the end of the 48 hour running length was found to be 0.142 g, which is about 51% reduction of surface coke compared to the coke formed in the blank operation of Example 2. Also, the amount of crushed coke was found to be 8.52 g, which is about 35.8% reduction of the crushed coke compared to the coke formed in the blank operation of Example 2. Furthermore, no evidence of corrosion by inductively coupled plasma (ICP) analysis of the crushed coke samples was observed. The memory operation of Embodiment 5 is denoted by M2 and the results are given in Figs.

Considering the data presented in Examples 4 and 5, the memory effect of the compositions of the present invention is very clear. Even after two blank runs without the composition of the present invention, a reduction of about 50% of the surface coke and a reduction of about 25-35% of the crushed coke were observed, indicating that even after the primary operation by the composition was completed, And clearly establishes the sustainable memory effect of

In addition, inductively coupled plasma (ICP) analysis of the coke samples from Examples 3, 4 and 5 also showed a decrease in metal leaching compared to the blank operation of Example 2 after addition of the compositions of the present invention and during memory operation, respectively Respectively. The results are illustrated in Fig.

Example 6 Elemental Analysis and Downstream Effect of Element from Additive Mixture

The elemental analysis may include bubbler water, steam condensate, organic liquid product, hydrocarbon feed, aqueous additive solution, TLE wash water, crushed coke, coke removal gas and cokes removal vapor condensate through which the product gas stream passes All streams are run to analyze the effect of the elements present in the composition of the invention and where the elements gather after completion of the experiment. The results obtained indicate that in the order of decreasing elemental composition - organic liquid product, crushed coke, vapor condensate and coke vapor condensate, about 1% of the total elements formed are able to collect in the TLE. In addition, the organic liquid vapors are for the separation of the various products and the elements will be retained in the oil and carbon black feedstock (CBFS). Elements of the composition deposited on the surface coke formed on the reactor surface are washed together with the coke removal steam water and precipitated in the vapor condensate. Thermogravimetric analysis (TGA) of the coke sample also showed reduced metal content in the test run comprising the composition disclosed in Figure 7 to support the observation of reduced metal leaching in the test run including compositions reported by ICP analysis . In addition, the pH of all samples was found to be in the pH range of the plant in the test run (R-412) with the composition provided below.

The product gas passes water through a glass bubbler to dissolve the element. The sample is labeled BWR. After operation, hot water passes through the condenser and is collected for analysis and indicated as TLEW. Samples from the steam condensate sent for analysis are called LPRW. The cracker liquid product is extracted with HNO ₃ , extracting the additive elements and expressed as ORGW.

R-408 R-412 Display BWR pH 6.389 8.44 Product steam TLEW pH 2.839 6.089 Condenser water LPRW pH 2.774 3.27 Steam condensate ORGW pH 1.013 1.056 Extraction of organic layer by HNO3

In view of the foregoing description and various embodiments, the present invention overcomes the various drawbacks of the prior art successfully and provides a composition that includes a metal salt, such as potassium carbonate and calcium acetate, optionally in the form of coke forming and / Can provide an improved method for reducing the formation and / or deposition of coke in the reactor system during decomposition of hydrocarbons by use with sulfur containing compounds that reduce deposition to 60%.

In this specification, the expressions of decomposition, decomposition of hydrocarbons, decomposition of hydrocarbons, and decomposition processes are used interchangeably, and the expressions of decomposition, decomposition of hydrocarbons, decomposition of hydrocarbons, decomposition processes refer to the same subject, wherein long chain hydrocarbons The same organic molecules break down into simpler molecules such as lighter hydrocarbons by breaking carbon-carbon bonds.

Additional embodiments and features of the present invention will be apparent to those skilled in the art based on the description provided herein. The embodiments of the present invention provide various features and advantages in the detailed description. Known / conventional methods and techniques are omitted in order not to unnecessarily obscure the embodiments of the present invention.

The foregoing description of certain embodiments is provided to enable any person skilled in the art to make and use the present invention without departing from the generic concept and to fully embody the general character of the present embodiments that may readily modify and / And such adaptations and modifications should be understood within the meaning and range of equivalents of the embodiments.

It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Thus, while embodiments of the invention have been described in connection with the preferred embodiments, those skilled in the art will recognize that embodiments of the invention may be practiced with modification within the spirit and scope of the embodiments described herein.

Throughout the invention, where used, the word " comprises ", or variations such as " comprises "or" comprising, " Integer, or group of steps, but it will be understood that it is not the exclusion of any other element, integer or step, or group of elements, integers, or steps.

With regard to the use of substantially any plural and / or single in the present invention, those skilled in the art can translate plural and / or singular and / or singular to plural as appropriate to the content and / or application fields. The various singular / plural permutations may be explicitly described in the present invention for clarity.

The use of the phrases "at least" or "at least one" refers to the use of one or more elements or components or amounts which are intended to achieve one or more desired entities or results in an embodiment of the invention.

The discussion of documents, acts, materials, devices, articles, and the like contained herein is provided solely to provide the context of the present invention. Some or all of these matters may not be recognized as general knowledge in the field of disclosure, such as being part of the prior art data or at any time prior to the priority date of this application.

While a great deal of emphasis has been placed on certain features of the invention, it will be appreciated that various modifications may be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or of preferred embodiments will be apparent to those skilled in the art from the present invention, and it should be explicitly understood that the description is illustrative of the invention and not in limitation.

SI. No. Reference numerals
1 100 system
2 10 Naphtha Tank
3 12 Water tank
4 14 naphtha balance
5 16 Water scales
6 18 Naphtha metering pump
7 20 Water Pump
8 22 Naphtha vaporizer
9 24 Water vaporizer
10 26 mixer
11 36 Reactor coil
12 38 Heating furnace
13 44 Transmission Line Heat Exchanger 1
14 46 Transmission Line Heat Exchanger 2
15 48 gas liquid separator
16 50 Wet gas meter
17 52 CO / CO ₂ analyzer
18 54 and 56 gas chromatography

Claims (13)

Optionally comprising an alkali metal salt and an alkaline earth metal salt together with a sulfur containing compound, wherein the composition reduces coke formation during hydrocarbon decomposition. The method according to claim 1,
The alkali metal salt is potassium carbonate and the alkaline earth metal salt is calcium acetate; The concentration of potassium carbonate and calcium acetate ranges from about 1 ppmw to 4 ppmw, with potassium carbonate at about 35% by weight and calcium acetate at about 65% by weight at this concentration. The method according to claim 1,
The sulfur containing compound is selected from the group consisting of dimethyl disulfide, dimethyl sulfide, diethyl sulfide, diethyl disulfide, carbon disulfide and dimethyl sulfoxide or any combination thereof and the concentration of the sulfur containing compound is about 50 ppmw To 250 ppmw. The method according to claim 1,
Wherein the composition is independently soluble in water and a polar solvent. The method according to claim 1,
The composition reduces coke formation during hydrocracking by at least 40% as compared to hydrocarbon cracking without the composition; The composition reduces at least 60% of the surface coke during hydrocarbon decomposition compared to hydrocarbon decomposition without the composition; Wherein the composition reduces at least 35% of the cracked coke during hydrocarbon cracking as compared to the hydrocarbon cracking without the composition. The method according to claim 1,
The composition further reduces coke formation by the memory effect of the composition during hydrocarbon decomposition, the memory effect of the composition being maintained for at least two cycles of hydrocracking; Wherein the surface coke is reduced at least 50% in a subsequent cycle and the crushed coke is reduced by at least 25% individually during hydrocarbon decomposition compared to hydrocarbon decomposition without the composition. The method according to claim 1,
Wherein the composition reduces metal leaching during hydrocracking by at least 40% compared to hydrocarbon decomposition without the composition. Optionally introducing a composition comprising potassium carbonate and calcium acetate together with a sulfur containing compound into a reactor system and hydrolyzing the reactor system. 9. The method of claim 8,
The composition is injected into the reactor system together with water or hydrocarbons or both; The hydrocarbons are selected from the group comprising naphtha, light oil, ethane and propane or any combination thereof; Wherein the reactor system is a cracker reactor. 9. The method of claim 8,
Wherein the concentration of potassium carbonate and calcium acetate is in the range of about 1 ppmw to 4 ppmw, with potassium carbonate at about 35 wt% and calcium acetate at about 65 wt% at said concentration. 9. The method of claim 8,
The sulfur containing compound is selected from the group consisting of dimethyl disulfide, dimethyl sulfide, diethyl sulfide, diethyl disulfide, carbon disulfide and dimethyl sulfoxide or any combination thereof and the concentration of the sulfur containing compound is about 50 ppmw To 250 ppmw. 9. The method of claim 8,
Wherein the hydrocarbon decomposition is carried out at a temperature in the range of about 800 < 0 > C to 850 < 0 > C. 9. The method of claim 8,
Coke formation during hydrocarbon decomposition is reduced by at least 40%, surface coke during hydrocarbon decomposition is reduced by 60%; Wherein the crushed coke during hydrocarbon decomposition is reduced by at least 35%.

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