Method for removing chlorine from waste plastic pyrolysis oil

Abstract

The present disclosure relates to a method for removing chlorine from waste plastic pyrolysis oil, the method comprising: (S1) mixing and reacting the waste plastic pyrolysis oil with a neutralizing agent containing M-OR1 and a neutralizing solution containing a solvent; and (S2) subjecting the fluid generated from the (S1) step to water treatment to remove chlorine, wherein M is an alkali metal or an alkaline earth metal, and R1 is any one of C1 to C2. 10 is an alkyl group.

Description

[Technical field]

[0001] The present disclosure relates to a method for removing chlorine from waste plastic pyrolysis oil. [Background technology]

[0002] Waste plastics are manufactured using petroleum as a raw material, and the recycling rate is low, so most of them are disposed of as garbage. Such waste takes a long time to decompose in natural conditions, so it pollutes the soil and causes serious environmental pollution. As a method for recycling waste plastics, it is possible to pyrolyze the waste plastics and convert them into usable fractions, which are called waste plastic pyrolysis oil.

[0003] However, pyrolysis oil obtained by pyrolyzing waste plastics contains higher amounts of impurities such as chlorine, nitrogen, and metals than fractions produced from crude oil using conventional methods. As such, it cannot be immediately used as high-value-added fuels such as gasoline and diesel oil and must go through a refining process.

[0004] In the past, chlorine was removed by converting it to HCl through hydrotreating in the presence of a hydrogenation catalyst in the refinery process, but waste plastic pyrolysis oil contains a high content of chlorine, and excessive HCl is generated during hydrotreating, causing problems such as equipment corrosion, reaction abnormalities, and deterioration of product properties. In addition, the HCl reacts with nitrogen compounds to produce ammonium salts (NH4Cl). This not only corrodes the reactor, reducing its durability, but also causes many process problems such as the generation of differential pressure and reduced process efficiency.

[0005] Prior Art 1 (JP Patent Publication 1999-504672A) relates to a method for producing gasoline, diesel engine oil and carbon black from waste rubber and / or waste plastic materials, and is characterized in that in the primary impurity removal process of pyrolysis oil obtained by pyrolyzing waste rubber and waste plastic, basic substances such as KOH and NaOH are used to remove chlorine, nitrogen and sulfur, and the cracked fraction is separated in the secondary catalytic cracking process to produce the final product. In the primary impurity removal process, chlorine is reduced through a neutralization process using basic substances such as KOH and NaOH, but this neutralization removal reaction does not have a high chlorine removal efficiency per unit weight of the basic substance, making it difficult to produce a fraction with a minimized chlorine content to a level that can be introduced into a refinery process, and strong basic neutralizing agents such as NaOH cause corrosion of equipment, resulting in various process problems such as abnormal reactions and reduced process efficiency.

[0006] In addition, conventional methods for reducing the chlorine in waste plastic pyrolysis oil include a washing process or a water treatment process, but these have the limitation that they only mainly remove inorganic chlorine from the pyrolysis oil and do not remove much organic chlorine.

[0007] Therefore, a technology is needed that can reduce both organic and inorganic chlorine to a few ppm level so that waste plastic pyrolysis oil, which contains high chlorine, can be introduced into the refinery process while minimizing problems such as equipment corrosion, abnormal reactions, and deterioration of product properties. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 1999-504672 (Publication date: April 27, 1999) Summary of the Invention [Problem to be solved by the invention]

[0009] The object of the present disclosure is to provide a method and device for removing chlorine from waste plastic pyrolysis oil, which can convert organic chlorine in the waste plastic pyrolysis oil into inorganic chlorine to effectively remove the organic chlorine, and can maximize the chlorine removal efficiency when combined with a downstream desalter process.

[0010] Another object of the present disclosure is to provide a method and apparatus for removing chlorine from waste plastic pyrolysis oil, which minimizes corrosion of a reactor during the chlorine removal process and improves process stability.

[0011] Another object of the present disclosure is to provide a method and device for removing chlorine from waste plastic pyrolysis oil, which can suppress or minimize the generation of ammonium salts (NH4Cl) during hydrotreatment in the refinery process by removing chlorine from the waste plastic pyrolysis oil to a level of several ppm, thereby enabling long-term stable operation. [Means for solving the problem]

[0012] The present disclosure provides a method for removing chlorine from waste plastic pyrolysis oil, comprising: (S1) a step of mixing and reacting the waste plastic pyrolysis oil with a neutralizing agent containing M-OR1 and a neutralizing solution containing a solvent; and (S2) a step of removing chlorine by water treatment of the fluid generated from the (S1) step. (The M is an alkali metal or an alkaline earth metal, and R1 is any one of C1 to C2. 10 is an alkyl group.

[0013] In one example of the present disclosure, the (S1) step may be carried out at a temperature of 300 to 500°C.

[0014] In one example of the present disclosure, in step (S1), M-OR1 may include Na-OR2.

[0015] In one example of the present disclosure, in the step (S1), the solvent may include an alcohol.

[0016] In one example of the present disclosure, the alcohol has a molecular weight of 25 to 800 g / mol and a viscosity of 0.5 to 1.1 g / cm 3 The density may be

[0017] In one example of the present disclosure, the difference in density between the waste plastic pyrolysis oil and the alcohol is 0.3 g / cm 3 It may be the following.

[0018] In one example of the present disclosure, in the step (S1), the solvent may further include water.

[0019] In one example of the present disclosure, the (S1) step may involve reacting the waste plastic pyrolysis oil, the neutralization solution, and an inorganic bead catalyst in a batch reactor.

[0020] In one example of the present disclosure, the (S1) step may be carried out by passing the waste plastic pyrolysis oil and the neutralized solution through a fixed bed reactor filled with an inorganic bead catalyst.

[0021] In one example of the present disclosure, the (S2) step may be carried out at 30 to 250° C. and 2 to 50 bar.

[0022] In one example of the present disclosure, the step (S2) may be performed by supplying cleaning water to the fluid generated in the step (S1), washing the fluid, and discharging the aqueous solution containing chlorine.

[0023] In one example of the present disclosure, 90% or more of chlorine in the waste plastic pyrolysis oil can be removed through the steps (S1) and (S2).

[0024] The present disclosure also provides a device for removing chlorine from waste plastic pyrolysis oil, the device including: a mixer into which a neutralizing agent containing M-OR1 and a solvent flow and are mixed; a reactor into which the neutralizing solution and the waste plastic pyrolysis oil generated from the mixer flow and react with each other; and a desalter into which the fluid generated from the reactor and washing water flow, impurities in the fluid are washed out, and an aqueous solution containing chlorine is discharged. (The M is an alkali metal or an alkaline earth metal, and R1 is any one of C1 to C5.) 10 is an alkyl group.

[0025] In one example of the present disclosure, the temperature of the reactor may be 300 to 500°C.

[0026] In one example of the present disclosure, the reactor may be a batch reactor into which the inorganic bead catalyst flows.

[0027] In one example of the present disclosure, the reactor may be a fixed bed reactor packed with a mineral bead catalyst.

[0028] In one example of the present disclosure, the desalter may further include an electric field application unit.

[0029] In one example of the present disclosure, the desalter includes a plurality of outlets, and the outlets may further include a density profiler.

[0030] In one example of the present disclosure, the temperature of the desalter may be 30 to 250° C. and the pressure may be 2 to 50 bar. Effect of the Invention

[0031] The method and device for removing chlorine from waste plastic pyrolysis oil disclosed herein can convert organic chlorine in waste plastic pyrolysis oil into inorganic chlorine to effectively remove organic chlorine, and can maximize the efficiency of chlorine removal when combined with a downstream desalter process.

[0032] The method and apparatus for removing chlorine from waste plastic pyrolysis oil according to the present disclosure can minimize corrosion of a reactor during the chlorine removal process and improve process stability.

[0033] The method and device for removing chlorine from waste plastic pyrolysis oil disclosed herein removes chlorine from the waste plastic pyrolysis oil to a few ppm level, thereby suppressing or minimizing the generation of ammonium salts (NH4Cl) during hydrotreatment in the refinery process, thereby enabling long-term stable operation. [Brief description of the drawings]

[0034] [Figure 1] FIG. 1 is a diagram illustrating a process for refining waste plastic pyrolysis oil using an alcohol solvent according to an example of the present disclosure. [Diagram 2] FIG. 1 illustrates a process for refining waste plastic pyrolysis oil using a co-solvent containing alcohol and water according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] The drawings described in this specification are provided as examples to fully convey the concept of the present disclosure to those skilled in the art. Therefore, the present disclosure is not limited to the drawings shown, and may be embodied in other forms, and the drawings may be exaggerated to clarify the concept of the present disclosure.

[0036] Unless otherwise defined, the technical and scientific terms used in this specification have the meanings that are commonly understood by those having ordinary knowledge in the technical field to which the present invention belongs, and in the following description and the attached drawings, descriptions of known functions and configurations that may obscure the gist of the present invention will be omitted.

[0037] As used herein, the singular forms of the terms "a," "an," and "the" can be construed as including the plural forms as well, unless otherwise indicated.

[0038] Numerical ranges used herein include lower and upper limits, all values ​​within the range, increments logically derived from the form and width of the range defined, all values ​​limited therein, and all possible combinations of upper and lower limits of numerical ranges limited in different forms from each other. Unless otherwise specified in the specification of the present invention, values ​​outside the numerical range that may occur due to experimental error or rounding of values ​​are also included in the defined numerical range.

[0039] As referred to in this specification, "comprising" is an open-ended term having the same meaning as terms such as "comprising," "containing," "having," "characterized," and the like, and does not exclude further unrecited elements, materials, or steps.

[0040] In this specification, the unit of % used without special mention means % by weight unless otherwise defined.

[0041] The ppm unit used in this specification without any special mention means ppm by mass unless otherwise defined.

[0042] Boiling points used in this specification, unless otherwise specified, refer to boiling points at 1 atmosphere.

[0043] Density used in this specification without any special mention means density at room temperature (25° C.).

[0044] In the M-OR1 used in this specification without any special reference, M means an alkali metal or an alkaline earth metal, and R1 is a C1 to C 10 It means an alkyl group containing the following formula:

[0045] The alkali metal or alkaline earth metal refers to a metal commonly used in the art. For example, the alkali metal may include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), or francium (Fr), and the alkaline earth metal may include beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), or radium (Ra).

[0046] As referred to herein, organochlorine means chlorine that is bound to an organic compound or organic polymer.

[0047] In the past, the refinery process of waste plastic pyrolysis oil was to convert chlorine into HCl and remove it by hydrotreating it in the presence of a hydrogenation catalyst, but waste plastic pyrolysis oil contains a high content of chlorine, and excessive HCl is generated during hydrotreating, causing problems such as equipment corrosion, reaction abnormalities, and deterioration of product properties. In addition, the HCl reacts with nitrogen compounds to generate ammonium salts (NH4Cl), which not only corrodes the reactor and reduces its durability, but also causes many process problems such as the generation of differential pressure and reduced process efficiency.

[0048] In addition, in the past, basic substances such as KOH and NaOH were used as the primary impurity removal process for pyrolysis oil obtained by pyrolyzing waste rubber and waste plastic to remove chlorine, nitrogen, sulfur, etc., and the cracked fraction was separated in the secondary catalytic cracking process to produce the final product. However, this neutralization removal reaction does not have a high chlorine removal efficiency per unit weight of the basic substance, making it difficult to produce a low-chlorine fraction (a few ppm of Cl) that can be used in the refinery process. In addition, strong basic neutralizing agents such as NaOH cause corrosion of equipment, leading to various process problems such as reaction abnormalities and reduced process efficiency.

[0049] As a method for reducing the chlorine in the waste plastic pyrolysis oil, a washing process or a water treatment process is carried out. However, this has the limitation that it mainly removes the inorganic chlorine in the pyrolysis oil and does not remove much of the organic chlorine.

[0050] Therefore, the present disclosure provides a method for producing a waste plastic pyrolysis oil by mixing and reacting the waste plastic pyrolysis oil with a neutralizing agent containing M-OR1 and a neutralizing solution containing a solvent (wherein M is an alkali metal or an alkaline earth metal, and R1 is any one of C1 to C2). 10 and (S2) a step of subjecting the fluid produced from step (S1) to water treatment to remove chlorine.

[0051] The waste plastic pyrolysis oil may be a mixture of hydrocarbon fractions produced by high-temperature pyrolysis of waste plastics. Here, the waste plastics may include solid or liquid wastes related to synthetic polymer compounds such as waste synthetic resins, waste synthetic fibers, waste synthetic rubber, and waste vinyl.

[0052] The hydrocarbon fraction mixture may contain impurities such as chlorine compounds, nitrogen compounds, metal compounds, etc., in addition to the hydrocarbon fraction, and the chlorine compounds may include both organic and inorganic chlorine. The hydrocarbon fraction mixture may also contain impurities in the form of compounds bound to metals, and may also contain hydrocarbons in the form of olefins.

[0053] The content of chlorine compounds in the waste plastic pyrolysis oil may be 50 ppm or more, specifically 100 ppm or more. The upper limit of the chlorine content is not particularly limited, but may be, for example, 1000 ppm or less, specifically 800 ppm or less.

[0054] The weight ratio of organic chlorine and inorganic chlorine contained in the chlorine compound may be 100:0 to 80, specifically 100:30 to 60, but this is merely an example and the weight ratio is not necessarily limited thereto.

[0055] In the step (S1) of mixing and reacting the waste plastic pyrolysis oil with a neutralizing solution containing a neutralizing agent including M-OR1 and a solvent, the organic chlorine in the waste plastic pyrolysis oil is converted to inorganic chlorine, and the converted inorganic chlorine may be trapped in the neutralizing solution containing the neutralizing agent and the solvent.

[0056] In one embodiment of the present disclosure, the (S1) step may be performed at a temperature of 300 to 500°C. When the waste plastic pyrolysis oil is treated at a high temperature of 300°C or more, the organic chlorine in the pyrolysis oil can be converted to inorganic chlorine, for example, HCl (hereinafter, HCl means inorganic chlorine). The organic chlorine forms a very strong bond with a hydrocarbon residue, and when the treatment is performed at 300°C or less, the efficiency of the organic chlorine being converted to HCl is low, and when the treatment is performed at 500°C or more, a cracking side reaction of the pyrolysis oil occurs, which may cause problems of catalyst inactivation and yield loss. The temperature may be specifically 350 to 450°C, more specifically 370 to 420°C.

[0057] The neutralizing agent containing M-OR1 can trap chlorine from the pyrolysis oil by reacting with HCl in the pyrolysis oil to generate NaCl, and can generate R1-OH as a by-product. Conventionally, strong basic neutralizing agents such as NaOH, KOH, Mg(OH)2, or Ca(OH)2 have been used as neutralizing agents for removing chlorine, but these cause corrosion of the reactor, which reduces reaction stability and has a fatal problem of reducing process efficiency. When using the neutralizing agent containing M-OR1, corrosion of the reactor can be suppressed, and the by-product R1-OH reacts with organic acids in the pyrolysis oil to reduce the total acid number (TAN).

[0058] In one example of the present disclosure, in the step (S1), M-OR1 may contain Na-OR2 (wherein R2 is an alkyl group having C1 to C4). It is preferable to use a Na-OR2 neutralizing agent containing sodium (Na) metal and an alkyl group having C1 to C4 in terms of solubility and reactivity with HCl.

[0059] The neutralizing agent containing M-OR1 may be contained in an amount of 0.05 to 5 parts by weight per 100 parts by weight of waste plastic pyrolysis oil. When the above range is satisfied, the chlorine compounds in the waste plastic pyrolysis oil can be efficiently trapped. Specifically, the neutralizing agent may be contained in an amount of 0.1 to 3 parts by weight, more specifically, 0.2 to 1 parts by weight.

[0060] By mixing the waste plastic pyrolysis oil with a neutralizing agent containing M-OR1 and a neutralizing solution containing a solvent, the neutralizing agent containing M-OR1 can be introduced more easily into the waste plastic pyrolysis oil. When the neutralizing agent containing M-OR1 is directly introduced into the waste plastic pyrolysis oil in a solvent-free form, the neutralizing agent does not easily mix with the pyrolysis oil and may aggregate, so by mixing with the pyrolysis oil in the form of a neutralizing solution, the neutralizing agent can be introduced more easily into the pyrolysis oil.

[0061] In one example of the present disclosure, in the step (S1), the solvent may include an alcohol. The alcohol solvent is a solvent that can easily dissolve M-OR1, and has a very high solubility of M-OR1 and NaCl, which is advantageous in terms of mixing the waste plastic pyrolysis oil and the neutralizing agent. Specifically, the alcohol solvent may include a mixture of at least one selected from ethanol, propanol, isopropanol, butanol, 2-ethylhexyl alcohol, butylene glycol, neopentyl glycol, dipropylene glycol, and tripropylene glycol, but this is merely an example, and various alcohols that have high solubility for the M-OR1 neutralizing agent may be used without being limited thereto.

[0062] The alcohol may have a boiling point of 70° C. or higher. Using an alcohol having a boiling point of 70° C. or higher may be advantageous in terms of operational stability, and specifically, the boiling point may be 90° C. or higher, more specifically, the boiling point may be 110° C. or higher, and, without limitation, the boiling point may be 300° C. or lower.

[0063] In one example of the present disclosure, the alcohol has a molecular weight of 25 to 800 g / mol and a viscosity of 0.5 to 1.1 g / cm 3 When the molecular weight and density are within the above ranges, it is advantageous in terms of mixing the waste plastic pyrolysis oil with the neutralization solution. Specifically, the molecular weight is 45 to 500 g / mol and the density is 0.7 to 1.1 g / cm. 3 More specifically, the molecular weight may be 45 to 300 g / mol and the density may be 0.7 to 0.9 g / cm. 3 may be also possible.

[0064] In one example of the present disclosure, the difference in density between the waste plastic pyrolysis oil and the alcohol is 0.3 g / cm 3 The difference in density may be 0.3 g / cm or less. 3 If the density difference is less than 0.3g / cm, the waste plastic pyrolysis oil and alcohol can be mixed more easily. 3If it is more than this, there may be a problem of layer separation due to the difference in density with the waste plastic pyrolysis oil. Specifically, the density difference is 0.2 g / cm 3 or less, more specifically 0.1 g / cm 3 or less, but is not limited to, 0 or more or 0.01 g / cm 3 It may be more than that.

[0065] In one example of the present disclosure, the solvent may further include water. Water has high solubility for HCl and can effectively trap HCl, and when the solvent further includes water together with alcohol, chlorine in the waste plastic pyrolysis oil can be efficiently removed. The solubility of HCl and NaCl in the cosolvent can be increased by dissolving a neutralizing agent including M-OR1 in a cosolvent including water and alcohol.

[0066] This is advantageous in that after organic chlorine is converted to HCl, it can be rapidly converted to NaCl by the neutralizing agent containing M-OR1, thereby suppressing corrosion of the reactor, and the generated NaCl does not precipitate in the solvent but dissolves in the co-solvent, and can be completely removed from the waste plastic pyrolysis oil by subsequent oil-water separation.

[0067] When water is further included as the solvent, the solvent may be included in an amount of 5 to 50 parts by weight relative to 100 parts by weight of the waste plastic pyrolysis oil. When the above range is satisfied, HCl in the waste plastic pyrolysis oil can be trapped more efficiently. Specifically, the solvent may be included in an amount of 5 to 40 parts by weight, more specifically, 5 to 30 parts by weight. When water is further included as the solvent, the weight ratio of water to alcohol as a co-solvent may be 100:5 to 100:50, specifically, 100:5 to 100:30.

[0068] When the solvent further includes water, the (S1) step may be performed at a temperature of 300 to 500° C. When water is used as a solvent under high temperature conditions of 300° C. or higher, it is possible to effectively prevent HCl in the waste plastic pyrolysis oil from recombining with olefins. Specifically, the temperature may be 330 to 400° C., more specifically, 350 to 380° C.

[0069] In one example of the present disclosure, the (S1) step may be performed by feeding the waste plastic pyrolysis oil, the neutralization solution, and the inorganic bead catalyst into a batch reactor to carry out the reaction. By feeding the inorganic bead catalyst into the reactor, the reaction heat can be dispersed, the waste plastic pyrolysis oil and the neutralization solution can be mixed more easily, and side reactions can be suppressed to improve the reaction efficiency. The reaction may be performed in an inert atmosphere, for example, a nitrogen atmosphere, and may be performed under conditions of a temperature of 350 to 500°C, a pressure of 5 to 50 bar, a time of 1 to 15 hours, and a stirring speed of 100 to 4000 rpm. Specifically, the reaction may be performed under conditions of a temperature of 350 to 500°C, a pressure of 5 to 25 bar, a time of 1 to 10 hours, and a stirring speed of 100 to 2000 rpm, but this is an example and is not limited thereto.

[0070] In one example of the present disclosure, the (S1) step may be performed by passing the waste plastic pyrolysis oil and the neutralization solution through a fixed bed reactor packed with an inorganic bead catalyst. The fixed bed reactor has the advantage of high productivity and may be operated in a continuous mode. After the waste plastic pyrolysis oil and the neutralization solution containing a neutralizing agent and a solvent containing M-OR1 are introduced into the fixed bed reactor packed with the inorganic bead catalyst, the reaction may be performed by adjusting various reaction conditions that control the reaction activity.

[0071] By carrying out the reaction under an inorganic bead catalyst, the waste plastic pyrolysis oil and the neutralization solution can be mixed more easily, and the reaction efficiency can be improved by forming a turbulent flow in the packed bed filled with the inorganic bead catalyst.

[0072] In one embodiment of the present disclosure, when the solvent is a co-solvent further containing water, the miscibility of the waste plastic pyrolysis oil and the co-solvent may be somewhat inferior to that of a solvent containing alcohol alone, and the rate at which HCl removed from the waste plastic pyrolysis oil is converted to NaCl may be low. However, by using a fixed bed reactor, despite the somewhat inferior miscibility, active material exchange occurs between the waste plastic pyrolysis oil and the co-solvent due to the turbulence generated in the packed bed, and HCl can be quickly dissolved in the co-solvent and converted to NaCl, so that the fixed bed reactor can provide a preferable advantage over the co-solvent.

[0073] The reaction may be carried out in an inert atmosphere, for example, a nitrogen atmosphere, at a temperature of 350 to 500° C., a pressure of 5 to 100 bar, and a liquid hourly space velocity (LHSV) of 0.1 to 10 h -1 Alternatively, the N2 / Oil ratio may be in the range of 50 to 2000. Specifically, the temperature is 350 to 450°C, the pressure is 5 to 50 bar, and the liquid hourly space velocity (LHSV) is 0.1 to 5 h -1 Alternatively, the N2 / Oil ratio may be in the range of 50 to 1000, but this is merely an example and is not intended to be limiting.

[0074] The inorganic bead catalyst may be any one or more catalysts selected from silica, alumina, and titania. The inorganic bead is not particularly limited in particle size as long as it is in a powder phase, but may be generally 500 nm to 10 μm for use as a catalyst. In terms of mixing the waste plastic pyrolysis oil and the neutralization solution, silica beads are preferred.

[0075] In one example of the present disclosure, the (S2) step may be performed through a step of supplying washing water to the fluid generated in the (S1) step, washing with water, and discharging an aqueous solution containing chlorine. In the (S1) step, the waste plastic pyrolysis oil and the neutralization solution are mixed and reacted with each other, so that the organic chlorine in the pyrolysis oil is converted to inorganic chlorine, and the inorganic chlorine is present in the neutralization solution in the form of NaCl. The chlorine in the waste plastic pyrolysis oil can be removed by supplying washing water to the fluid containing NaCl, washing with water, and discharging an aqueous solution containing chlorine, and not only NaCl but also remaining organic chlorine and nitrogen can be removed. The washing water may be water or distilled water, but is not necessarily limited thereto.

[0076] Specifically, when the fluid is mixed with wash water, water-soluble impurities contained in the fluid move to the water layer, and oil-water separation occurs, and the mixture of the fluid and wash water is separated into an oil layer and a water layer. Since the water layer contains an aqueous solution containing chlorine, the oil layer may be collected immediately or after removing the water layer, and the water layer may be discharged or recycled to the (S3) step after purification.

[0077] An electric field may be applied to effectively separate the oil layer and the water layer, and the oil layer and the water layer may be separated in a short time by electrostatic adhesion caused by the application of an electric field. In addition, an additive may be added as necessary to improve the oil-water separation efficiency, and the additive may be a conventional demulsifier well known in the art.

[0078] In one example of the present disclosure, the (S2) step may be performed at 30 to 250° C. and 2 to 50 bar. Specifically, the step may be performed at 30 to 200° C. and 2 to 40 bar, and may be performed in an inert atmosphere, for example, a nitrogen atmosphere. When the water treatment step is performed under the above conditions, the efficiency of oil-water separation can be improved.

[0079] In one embodiment of the present disclosure, the chlorine in the waste plastic pyrolysis oil can be removed by 90% or more through the steps (S1) and (S2). As described above, the organic chlorine in the waste plastic pyrolysis oil can be converted to inorganic chlorine and removed to obtain waste plastic pyrolysis oil with chlorine reduced by 90% or more. Specifically, the chlorine in the waste plastic pyrolysis oil can be removed by 95% or more, but not limited to 99% or less.

[0080] The present disclosure also provides a chlorine removal device for waste plastic pyrolysis oil, comprising: a mixer into which a neutralizing agent containing M-OR1 and a solvent flow and mix; a reactor into which the neutralizing solution and waste plastic pyrolysis oil generated from the mixer flow and into which the neutralizing solution and the waste plastic pyrolysis oil react; and a desalter into which the fluid generated from the reactor and wash water flow, into which impurities in the fluid are washed away, and into which an aqueous solution containing chlorine is discharged.

[0081] The content of the chlorine compound in the waste plastic pyrolysis oil may be 50 ppm or more, specifically 100 ppm or more. The upper limit of the chlorine content is not particularly limited, but may be, for example, 1000 ppm or less, specifically 800 ppm or less. The weight ratio of organic chlorine and inorganic chlorine contained in the chlorine compound may be 100:0-80, specifically 100:30-60, but this is an example and the weight ratio is not necessarily limited thereto.

[0082] The neutralizer containing M-OR1 and the solvent may flow into the mixer and be mixed. The mixer may include an inlet, and as shown in Figures 1 and 2, the neutralizer containing M-OR1 and the solvent flow into the inlet, respectively, and the order of flow is not particularly limited. Figure 1 illustrates a case where an alcohol solvent is used, and Figure 2 illustrates a case where a co-solvent containing alcohol and water is used. The mixing of the neutralizer containing M-OR1 and the solvent flowing into the mixer may be performed by a conventionally known method, and for example, by including a conventional mixer, the neutralizer and the solvent can be mixed uniformly.

[0083] The neutralization solution produced from the mixer and the waste plastic pyrolysis oil flow into the reactor, and the organic chlorine in the waste plastic pyrolysis oil is converted to inorganic chlorine, and the converted inorganic chlorine can be trapped in the neutralization solution containing a neutralizing agent and a solvent.

[0084] The reactor is connected to the mixer through a first pipe, and the neutralizing solution flows from the mixer to the reactor through the first pipe. The waste plastic pyrolysis oil may be mixed with the neutralizing solution and flow into the reactor through a second pipe connected to the first pipe. According to another example, the waste plastic pyrolysis oil may flow into the reactor through a second pipe connected to the reactor and react with the neutralizing solution.

[0085] The reactor may be in the form of a batch reactor or a fixed bed reactor.

[0086] In one embodiment of the present disclosure, the reactor may be a batch reactor, and an inorganic bead catalyst may be introduced into the reactor. The reactor may further include another inlet, and by introducing the inorganic bead catalyst through the inlet, the waste plastic pyrolysis oil and the neutralization solution may be mixed more easily, and the reaction efficiency may be improved. The reaction may be carried out in an inert atmosphere, for example, a nitrogen atmosphere, and specific reaction conditions may be referred to the above-mentioned method for removing chlorine from waste plastic pyrolysis oil.

[0087] In one embodiment of the present disclosure, the reactor may be a fixed bed reactor filled with an inorganic bead catalyst. The fixed bed reactor has the advantage of high productivity and may be operated in a continuous mode. After the waste plastic pyrolysis oil and the neutralizing solution containing the neutralizing agent and solvent containing M-OR1 are introduced into the fixed bed reactor filled with the inorganic bead catalyst through the pipe, the reaction may be carried out by adjusting various reaction conditions that control the reaction activity. By carrying out the reaction under an inorganic bead catalyst, the waste plastic pyrolysis oil and the neutralizing solution can be more easily mixed, and the reaction efficiency can be improved. The reaction may be carried out in an inert atmosphere, for example, a nitrogen atmosphere, and the specific reaction conditions may be referred to the above-mentioned method for removing chlorine from waste plastic pyrolysis oil.

[0088] In one embodiment of the present disclosure, the temperature of the reactor may be 300 to 500°C. When the temperature of the reactor is 300 to 500°C, the organic chlorine in the waste plastic pyrolysis oil can be converted to inorganic chlorine, for example, HCl (hereinafter, HCl means inorganic chlorine). The organic chlorine forms a very strong bond with the hydrocarbon residue, and when the temperature of the reactor is 300°C or less, the efficiency of converting the organic chlorine to HCl is low, and when the temperature is 500°C or more, a cracking side reaction of the pyrolysis oil occurs, which may cause problems of catalyst inactivation and yield loss. The temperature may be specifically 350 to 450°C, more specifically 370 to 420°C.

[0089] The neutralizing agent may include M-OR1. The neutralizing agent can trap chlorine from the pyrolysis oil by reacting with HCl in the pyrolysis oil to generate NaCl, and can generate R1-OH as a by-product. When the neutralizing agent including M-OR1 is used, corrosion of the reactor can be suppressed, and the by-product R1-OH has the effect of reducing the total acid number (TAN) by reacting with the organic acid in the pyrolysis oil.

[0090] The waste plastic pyrolysis oil, the neutralizing agent containing M-OR1, and the neutralizing solution containing a solvent are mixed in a reactor, so that the neutralizing agent containing M-OR1 can be introduced more easily into the waste plastic pyrolysis oil. If the neutralizing agent containing M-OR1 is directly introduced into the pyrolysis oil without a solvent, the neutralizing agent may not be mixed into the pyrolysis oil and may aggregate. By dissolving the neutralizing agent containing M-OR1 in a solvent and using it in the form of a neutralizing solution, the neutralizing agent can be introduced more easily into the waste plastic pyrolysis oil.

[0091] Chlorine compounds may be removed from the waste plastic pyrolysis oil through a desalter into which the fluid and washing water generated from the reactor flow and into which an aqueous solution containing chlorine is discharged. In the reactor, a fluid is generated in which the waste plastic pyrolysis oil and the neutralization solution are mixed, and organic chlorine in the pyrolysis oil is converted into inorganic chlorine, and the inorganic chlorine exists in the form of NaCl in the fluid. The fluid containing NaCl and washing water flow into a desalter, and the fluid is washed in the desalter, and then an aqueous solution containing chlorine is discharged, thereby removing chlorine from the waste plastic pyrolysis oil. In addition to NaCl, remaining organic chlorine and nitrogen can also be removed.

[0092] The desalter is connected to the reactor through a third pipe, and a fluid is introduced from the reactor to the desalter through the third pipe. In one embodiment, wash water may be mixed with the fluid and introduced to the desalter through a fourth pipe connected to the third pipe. In another embodiment, wash water may be introduced to the desalter through a fourth pipe connected to the desalter and then mixed with the fluid.

[0093] Specifically, after the fluid and wash water flow into the desalter, water-soluble impurities contained in the fluid can move to a water layer through a mixing means, and then the mixture of the fluid and wash water is separated into an oil layer and a water layer. The water layer contains an aqueous solution containing chlorine, and the oil layer may be collected through the top of the desalter or collected after removing the water layer, and the water layer may be discharged outside the system or recycled to the desalter after purification.

[0094] The desalter may further include an electric field application unit to apply an electric field for effective separation of the oil layer and the water layer. The oil layer and the water layer can be separated in a short time by electrostatic adhesion caused by the application of the electric field.

[0095] The desalter may include a plurality of outlets attached at positions different from each other in height. A chlorine-containing aqueous solution may be discharged through the outlets. The number of the outlets may be 2 to 5, specifically, 2 to 4, but is not limited thereto. The number of the outlets may be 60% or less of the total height of the desalter. This is usually in consideration of the position where a water layer is formed, and the outlets may be attached at a height of 50% or less, specifically, 10 to 40%, but is not limited thereto.

[0096] The outlet of the desalter may further include a density profiler, and by detecting the density, the oil layer can be prevented from being removed together with the water layer when the water layer is removed.

[0097] In one example of the present disclosure, the temperature of the desalter may be 30 to 250°C and the pressure may be 2 to 50 bar. Specifically, the temperature may be 30 to 200°C and the pressure may be 2 to 40 bar, and the atmosphere of the desalter may be an inert atmosphere, for example, a nitrogen atmosphere. When the above conditions are satisfied, the efficiency of oil-water separation can be improved.

[0098] For matters not further described in the chlorine removal device for waste plastic pyrolysis oil, please refer to the contents described in the above-mentioned chlorine refining method for waste plastic pyrolysis oil.

[0099] Hereinafter, the present disclosure will be described in detail with reference to examples. However, these are provided for the purpose of providing a more detailed description, and the scope of the invention is not limited to the following examples.

[0100] Example 1 Waste plastic was pyrolyzed to prepare 1000 g of waste plastic pyrolysis oil raw material.

[0101] The total chlorine, organic chlorine and inorganic chlorine contents (ppm) in the waste plastic pyrolysis oil feedstock were measured by ICP and XRF analysis and are shown in Table 1 below.

[0102] [Table 1]

[0103] 1.21 g of NaOC2H5 neutralizer and 20 g of ethanol solvent were added to a mixer and stirred to prepare a neutralized solution. The waste plastic pyrolysis oil and neutralized solution were added to a continuous fixed-bed reactor filled with silica beads (SSD-5003, Bangs Laboratories, Inc.) with an average particle size of 1 mm, and the reaction was carried out under a nitrogen atmosphere under the conditions shown in Table 2 below.

[0104] [Table 2]

[0105] After the reaction, the produced fluid and 200 g of washing water were put into a desalter and subjected to a water treatment process under conditions of 90°C and 5 bar in a nitrogen atmosphere. Finally, waste plastic pyrolysis oil with reduced impurities was obtained through the water treatment process.

[0106] Example 2 In Example 1, the reaction was carried out under the same conditions as in Example 1, except that the reactor temperature was 380°C, the desalter temperature was 150°C, and the pressure was 15 bar, and waste plastic pyrolysis oil with reduced impurities was obtained.

[0107] Example 3 A reaction was carried out under the same conditions as in Example 1, except that NaOCH3 was used as the neutralizing agent and dipropylene glycol was used as the solvent, to obtain waste plastic pyrolysis oil with reduced impurities.

[0108] Example 4 In Example 1, 1.21 g of the same NaOC2H5 neutralizing agent and 20 g of ethanol solvent were added to the mixer, and then 100 g of water was introduced into the front stage of the reaction section. Except for this, the reaction was carried out under the same conditions as in Example 1, and a waste plastic pyrolysis oil with reduced impurities was obtained.

[0109] Example 5 In Example 4, the reaction was carried out under the same conditions as in Example 4, except that the reactor temperature was 380°C, the desalter temperature was 150°C, and the pressure was 15 bar, and waste plastic pyrolysis oil with reduced impurities was obtained.

[0110] Comparative Example 1 A reaction was carried out under the same conditions as in Example 1, except that the temperature of the reactor was set to 250°C, to obtain waste plastic pyrolysis oil with reduced impurities.

[0111] Comparative Example 2 In Example 4, the reaction was carried out under the same conditions as in Example 4, except that the temperature of the reactor was set to 250°C, and a waste plastic pyrolysis oil with reduced impurities was obtained.

[0112] Comparative Example 3 A reaction was carried out under the same conditions as in Example 1, except that no solvent was used, to obtain a waste plastic pyrolysis oil with reduced impurities.

[0113] Comparative Example 4 A reaction was carried out under the same conditions as in Example 1, except that glycerol was used as the solvent, to obtain a waste plastic pyrolysis oil with reduced impurities.

[0114] Comparative Example 5 A reaction was carried out under the same conditions as in Example 1, except that NaOH was used as the neutralizing agent, to obtain a waste plastic pyrolysis oil with reduced impurities.

[0115] Evaluation example Chlorine Content The total chlorine, organic chlorine and inorganic chlorine contents (ppm) in the obtained waste plastic pyrolysis oil were measured by ICP and XRF analysis.

[0116] Corrosion susceptibility Corrosion susceptibility was evaluated by introducing test pieces inside the reactor and checking for the presence or absence of corrosion on the test pieces. Specifically, small test pieces made of the same material as the reactor were introduced under the catalyst layer inside the reactor and operation was carried out. Experiments were carried out according to operating conditions, and after operation, the catalyst and test pieces inside the reactor were removed and the surface of the test pieces was checked by image analysis. The reactor was made of Hastelloy material, and Hastelloy test pieces were separately introduced under the catalyst layer.

[0117] Maximum operating time The maximum operating time was measured as follows. A hydrotreating process was carried out on the waste plastic pyrolysis oil obtained in Examples 1 to 5 and Comparative Examples 1 to 5. Specifically, the obtained waste plastic pyrolysis oil and hydrogen gas were put into a hydrotreating reactor, and hydrotreating was carried out under conditions of 350°C and 60 bar in the presence of a NiMoS / γ-Al2O3 hydrotreating catalyst. The maximum operating time required for the pressure drop (delta P) due to the ammonium salt (NH4Cl) generated during the hydrotreating process to reach 7 bar was measured.

[0118] The measurement results are shown in Table 3 below.

[0119] [Table 3]

[0120] evaluation In Examples 1 and 2, it can be confirmed that the organic chlorine content of the waste plastic pyrolysis oil raw material, which has an organic chlorine content of 396 ppm, is reduced to 35 ppm or less by reacting with a neutralizing solution containing NaOC2H5 neutralizing agent and ethanol solvent in a reactor.

[0121] In Examples 4 and 5, the organic chlorine content was reduced to 28 ppm or less, which confirms that the organic chlorine removal effect is the best when a co-solvent containing ethanol and water is used.

[0122] In Example 3, the organic chlorine content was measured to be 47 ppm. By using NaOCH3 neutralizing agent and dipropylene glycol solvent, the organic chlorine removal effect was somewhat lower than in Examples 1 and 2, but it was confirmed that the effect was superior to Comparative Examples 1 to 5.

[0123] In addition, in all of the above Examples 1 to 5, the waste plastic pyrolysis oil was passed through a desalter and inorganic chlorine was effectively removed, so it was confirmed that the total chlorine 2 content in the final pyrolysis oil was significantly reduced.

[0124] On the other hand, in the case of Comparative Example 1 and Comparative Example 2, it can be confirmed that the organic chlorine in the pyrolysis oil is not converted to HCl by carrying out the reaction at 250°C, and the organic chlorine content is hardly reduced to more than about 350 ppm.

[0125] In the case of Comparative Example 3, it can be seen that since only the neutralizing agent is used without a solvent, coagulation occurs and it is not easily mixed with the pyrolysis oil, and the organic chlorine content is hardly reduced to 356 ppm. In addition, it can be seen that the low solubility of the neutralizing agent causes pressure loss (del P), making it difficult to perform stable operation.

[0126] In the case of Comparative Example 4, it was confirmed that the glycerol solvent was not easily mixed with the pyrolysis oil due to its high density, and the organic chlorine content was barely reduced to 349 ppm. It was also confirmed that pressure loss (del P) occurred during the operation, making it difficult to perform stable operation.

[0127] It can be confirmed that the maximum operating time was 15 days or more in all of the obtained Examples 1 to 5, and that the operation could be stably performed for a long period of time. This is considered to be because the total chlorine content in the waste plastic pyrolysis oil is reduced, thereby suppressing the generation of ammonium salt (NH4Cl). On the other hand, it can be confirmed that the total chlorine content in the pyrolysis oil is high in the cases of Comparative Examples 1 to 4, and the maximum operating time was significantly short at 5 days or less in all of the cases.

[0128] In Examples 1 to 5, after 30 days of reactor operation, it was confirmed whether Cl-stress occurred on the surface of the sample, and no cracks or pinholes due to Cl were found, confirming that there was no effect of corrosion even after operation for a long period of time of 30 days or more. On the other hand, in Comparative Example 5, after about 12 days of reactor operation, alkali corrosion occurred on the surface of the sample, confirming that the NaOH neutralizing agent caused corrosion of the reactor.

[0129] Although the embodiments of the present invention have been described above, the present invention is not limited to the above examples, and may be implemented in various different forms, and a person having ordinary skill in the art to which the present invention belongs can understand that the present invention may be implemented in other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above-described examples are illustrative in all respects and are not limiting.

Claims

1. (S1) Waste plastic pyrolysis oil is treated as M-OR １ and reacting with a neutralizing solution comprising a neutralizing agent and a solvent comprising: (S2) a step of treating the fluid produced from the (S1) step to remove chlorine; M is an alkali metal or an alkaline earth metal, R １ is C １ ~C １０ A method for removing chlorine from waste plastic pyrolysis oil, which is an alkyl group.

2. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the (S1) step is carried out at a temperature of 300 to 500°C.

3. In the step (S1), １ is Na-OR ２ Including, The R ２ is C １ ~C ４ The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the alkyl group is one of the following:

4. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1 , wherein in the step (S1), the solvent includes alcohol.

5. The molecular weight of the alcohol is 25 to 800 g / mol and the density is 0.5 to 1.1 g / cm ３ The method for removing chlorine from waste plastic pyrolysis oil according to claim 4,

6. The density difference between the waste plastic pyrolysis oil and the alcohol is 0.3 g / cm ３ The method for removing chlorine from waste plastic pyrolysis oil according to claim 4, wherein:

7. The method for removing chlorine from waste plastic pyrolysis oil according to claim 4 , wherein the solvent further contains water.

8. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the (S1) step comprises adding an inorganic bead catalyst to a batch reactor together with the waste plastic pyrolysis oil and the neutralization solution to carry out a reaction.

9. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the (S1) step is carried out by passing the waste plastic pyrolysis oil and the neutralized solution through a fixed-bed reactor filled with an inorganic bead catalyst.

10. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the (S2) step is carried out at 30 to 250° C. and 2 to 50 bar.

11. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein the step (S2) is carried out by supplying cleaning water to the fluid produced in the step (S1), washing the fluid, and discharging an aqueous solution containing chlorine.

12. The method for removing chlorine from waste plastic pyrolysis oil according to claim 1, wherein 90% or more of the chlorine in the waste plastic pyrolysis oil is removed through steps (S1) and (S2).

13. M-OR １ a mixer into which the neutralizing agent and the solvent flow and are mixed to generate a neutralized solution; A reactor into which the neutralization solution and the waste plastic pyrolysis oil generated in the mixer flow and react with each other; a desalter into which the fluid produced from the reactor and washing water are introduced, impurities in the fluid are washed, and an aqueous solution containing chlorine is discharged, M is an alkali metal or an alkaline earth metal, R １ is C １ ~C １０ This is a device for removing chlorine from pyrolysis oil of waste plastics, which is an alkyl group.

14. The apparatus for removing chlorine from waste plastic pyrolysis oil according to claim 13, wherein the temperature of the reactor is 300 to 500°C.

15. The chlorine removal device for waste plastic pyrolysis oil according to claim 13, wherein the reactor is a batch reactor and an inorganic bead catalyst flows into the reactor.

16. The chlorine removal device for waste plastic pyrolysis oil according to claim 13, wherein the reactor is a fixed-bed reactor packed with an inorganic bead catalyst.

17. The apparatus for removing chlorine from waste plastic pyrolysis oil according to claim 13, wherein the desalter further comprises an electric field application unit.

18. The apparatus for removing chlorine from waste plastic pyrolysis oil according to claim 13, wherein the desalter comprises a plurality of outlets, and the outlets further comprise a density profiler.

19. The apparatus for removing chlorine from waste plastic pyrolysis oil according to claim 13, wherein the temperature of the desalter is 30 to 250° C. and the pressure is 2 to 50 bar.

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