Reduced-type iron oxide-containing ceramic catalyst and producing method therefor

Abstract

The present invention relates to a reduced-type iron oxide-containing ceramic catalyst and a producing method therefor, wherein the ceramic catalyst comprises various iron oxides with different oxidation states supported on zeolite and can solve the disadvantages of an existing clay-aluminosilicate-zeolite waste plastic pyrolysis catalyst.

Description

Ceramic catalyst containing reduced iron oxide and method for producing the same

[0001] The present invention relates to a reduced iron oxide-containing ceramic catalyst in which various iron oxides with different oxidation states are supported on zeolite, which can improve the shortcomings of existing clay-aluminosilicate-zeolite waste plastic pyrolysis catalysts, and a method for producing the same.

[0002] Natural aluminosilicate catalysts, including synthetic zeolite, are being used as waste plastic pyrolysis catalysts, but the Lewis acidity of each substance is high or low, which reduces their effectiveness as waste plastic pyrolysis catalysts.

[0003] Solid waste plastic polymers are large polymers of hydrocarbons. As temperatures rise, their internal molecular breakdown accelerates, decomposing into semi-solid waxy substances, liquid hydrocarbons, and gaseous components. This process, which occurs naturally without the aid of a catalyst, is defined as pyrolysis, while decomposition accelerated in the presence of a catalyst is called catalyzed cracking or catalytic pyrolysis.

[0004] Appropriate carriers and catalyst materials are required to improve and control the efficiency and selectivity of catalytic decomposition.

[0005] The main components of catalysts are single or complex metals and their oxidizing and reducing agents. Materials with high electrical charge are primarily used. These metals are adsorbed, impregnated, and fixed to the surface of a support, ranging in size from nanometers to several millimeters, to perform their respective functions.

[0006] Iron oxides that commonly exist in nature include FeO, Fe2O3, Fe3O4, Fe(II), and Fe(III).

[0007] The existing method of supporting a reduced transition metal was performed by immersing zeolite in an ion water solution, drying it, and then calcining it at high temperature in a hydrogen atmosphere. However, this existing method has the disadvantages of a complicated process and a low content of the supported transition metal, and waste plastic pyrolysis oil containing a large amount of impurities rapidly reduces the activity of the catalyst, making it impossible to avoid performance degradation due to poisoning.

[0008] Even though the high activity of expensive rare metals and nanoparticles is maintained, it shows a defect that makes its continued usability very vulnerable.

[0009] The previously known reduced transition metal zeolite support technology involves a step-by-step process involving infiltrating or ion-exchanging aqueous solutions of transition metal or rare metal ions in the form of nitrates into a zeolite support, followed by drying and calcination. During the calcination process, the oxidation / reduction states of the metal ions can be controlled by varying oxygen and hydrogen atmospheres. However, forming the metal-reducing atmosphere with hydrogen presents significant challenges due to process risks and handling difficulties. Furthermore, high-temperature calcination increases energy costs.

[0010] Zeolites are typically classified as natural or synthetic. They are hydrated aluminosilicates containing alkaline earth metals. They have numerous micropores and a large pore surface area, giving them the advantage of high adsorption capacity. Furthermore, most zeolites are synthesized with homogeneous pores during their formation process (including synthesis).

[0011] Representative uses of zeolite include gas adsorption, ion exchange, catalyst support, or catalyst. The structural homogeneity of zeolite means that it only exhibits adsorption and reaction performance when the molecular size of the substance to be adsorbed or reacted is similar to the size of the zeolite micropores. Therefore, it often only provides adsorption performance for a single chemical substance. This means that it does not have comprehensive adsorption and reaction performance for various reactants. This is one of the biggest drawbacks of zeolite as an adsorption, reaction material, and catalyst.

[0012] According to the "Method for Removing Nitrate Nitrogen in Aqueous Solution Using Finely Reduced Iron (Fe) Powder," disclosed in Korean Patent Application No. 10-1998-0017342, a wet chemical reaction product for obtaining finely reduced iron (Fe) and a method for utilizing the same are described. This process inevitably involves complexity and does not address the purpose or method of loading the iron onto zeolite.

[0013] The "Method for Manufacturing Reduced Iron (Fe)" disclosed in Korean Patent Application No. 10-2006-0130053 relates to a manufacturing method for preventing re-oxidation of iron (Fe) by simply controlling the ratio of carbon source materials and iron (Fe) in a reduction furnace.

[0014] "Method for producing siliceous fertilizer using zeolite sintered balls" disclosed in Korean Patent Application No. 10-2007-0039086 is a method for using ball-shaped granules obtained by mixing and kneading zeolite powder and bentonite powder and then sintering them as a substitute for siliceous fertilizer, and relates to a method for sintering zeolite balls at a high temperature of 600 to 1000°C. This does not contain content for modifying the adsorption pores of zeolite or for adhering a metal salt and imparting selective adsorption properties like an adsorbent.

[0015] The "Method for Manufacturing a Porous Composite Sintering Agent" disclosed in Korean Patent Application No. 10-2007-0121783 involves mixing plate-shaped clay minerals with carbon materials and then using a binder mixed with colloidal silica such as sodium and vanadium compounds to create a composite sintered body. This is a method for low-temperature sintering (250 to 500°C) and has limitations in that it only restricts physical techniques for maintaining strength while avoiding the transformation of plate-shaped clay minerals of the illite system.

[0016] Most zeolite-related patents in foreign patents pertain to catalytic pyrolysis and synthesis of petrochemicals. These involve supporting various metal salts, such as nickel, vanadium, cobalt, platinum, and palladium, on zeolite carriers and then drying and calcining them. This process utilizes the ion exchange capacity of zeolite to perform wet loading followed by dry calcination.

[0017] There are no cases of manufacturing a catalyst exclusively for the pyrolysis of waste plastics, and there are cases where various rare metal catalysts used in hydrogenation reactions, along with Ni-Mo and Co-Mo catalysts used in the existing oil refining and petrochemical industries, are used as catalysts for the pyrolysis of waste plastics.

[0018] Although there are cases where zeolite alone is used to thermally decompose waste plastics or waste oil, it is rare to see it used as a commercial catalyst to control the molecular weight distribution related to the quality of pyrolysis oil, or to control the various yields of gas, naphtha, and kerosene.

[0019] In addition, when pyrolyzing a mixture of various waste plastics, it may be vulnerable to poisoning by foreign substances, and there are still few cases of commercial models that meet the characteristics of molded bodies and process requirements for use in the atmospheric pressure, low temperature pyrolysis process.

[0020] The present invention aims to improve the selective pyrolysis function of aluminosilicate zeolites used for the purpose of waste plastic pyrolysis. There are three major drawbacks to using zeolites as catalysts for waste plastic pyrolysis oil. First, the diversity of transition metals utilized as reaction catalysts is limited. Second, the concentration of supported ions is limited when supporting transition metal salts through ion exchange. Third, the price of zeolites is high, the supporting and forming processes of catalyst materials are complicated, and the pyrolysis oil containing many impurities causes poisoning, resulting in a shortened lifespan and increased operating costs.

[0021] The present invention improves surface charge by loading nano-reduced iron (Fe) onto zeolite, and physically blocks the pores of the zeolite to enhance adsorption selectivity. Furthermore, the physical surface area is improved by loading activated carbon, and the reduced iron (Fe) is loaded onto this to improve chemical adsorption characteristics.

[0022] The aim is to provide a thermal decomposition catalyst that improves the manufacturing unit cost compared to the product performance for the application of zeolite, while simplifying the manufacturing method to improve the manufacturing process efficiency.

[0023] The method for producing a reduced iron oxide-containing ceramic catalyst of the present invention for solving the above problem comprises the steps of: a first step of producing a mixed powder and an emulsion, respectively; a second step of mixing the mixed powder and the emulsion and then producing a kneaded dough; and a third step of performing a calcination process on the kneaded dough at 500°C or lower to produce a calcined product; wherein the mixed powder comprises a clay mineral and an aluminosilicate zeolite, and the emulsion comprises at least one selected from a metal inactivator, an anionic surfactant, petroleum, and methyl oleate.

[0024] In addition, the present invention relates to a ceramic catalyst containing reduced iron oxide manufactured by the above method, wherein the catalyst-containing iron oxide component includes oxidized iron oxide and reduced iron oxide, and includes 15 to 85 wt% of oxidized iron oxide of Fe2O3; and 15 to 85 wt% of reduced iron oxide containing FeO and Fe3O4.

[0025] In addition, the reduced iron oxide-containing ceramic catalyst of the present invention can be used as a waste plastic pyrolysis catalyst, a petrochemical catalyst, an interior tile, a building material, an air purifying material, a water treatment material, and / or a fertilizer material.

[0026]

[0027] According to the present invention, the process of supporting reduced iron with different oxidation numbers on the surface of zeolite can be simplified and the selective catalytic action can be dramatically improved.

[0028] Since the combustion heat of the carbon filler and the oxidation heat generated by the combustion promotion effect of the iron itself can be additionally obtained, the production process cost and time can be reduced. In addition, if a metal deactivator as an additive is added / calcined to suppress the inevitable oxidation of iron during the combustion process, a groundbreaking result can be achieved in the production / support of reduced iron. Such reduced iron-supported zeolites can be used as catalysts in petrochemical processes, and the selective adsorption capacity of low molecular weight pyrolysis vapors can be improved and surface catalytic decomposition can be promoted due to the surface polarity modification of the zeolite and the change in the pore characteristics of the zeolite generated during the reduced iron support process.

[0029] The present invention can be applied to the manufacture of transition metal-supported zeolite catalysts or honeycomb-based catalysts used as petrochemical catalysts. By securing a variety of highly active reduced-form iron oxides, the selectivity of catalytic reactions can be enhanced.

[0030] The present invention can be used in a waste plastic pyrolysis process to convert waste plastic into pyrolysis oil through cracking and isomerization of high-molecular hydrocarbons such as plastic, thereby suppressing the production of high-boiling-point hydrocarbons such as wax, thereby producing high-quality pyrolysis oil from waste plastic.

[0031] Therefore, according to the present invention, the complexity and cost of the manufacturing process of a zeolite catalyst supporting a reduced iron compound can be improved, and the loading concentration of the selective catalyst can be dramatically increased.

[0032] Figure 1 shows the results of measuring the dewaxing rate using the control group and ceramic catalysts of Examples 1 to 6 conducted in Experimental Example 1.

[0033] Figures 2a to 2g show the results of measuring the pyrolysis yield and hydrocarbon content of waste plastic using the ceramic catalysts of the control group and Examples 1 to 6, respectively.

[0034] Figure 3 is a schematic diagram of a pyrolysis process, where A is a schematic diagram of a lab-scale pyrolysis process using a ceramic catalyst, and B is a schematic diagram of a lab-scale pyrolysis process without a catalyst.

[0035] Figure 4 shows the TGA analysis results of the ceramic catalyst manufactured in Example 1.

[0036] Figure 5 is an SEM measurement image of the ceramic catalyst manufactured in Example 1, where A is an image at 200x magnification, B is an image at 800x magnification, C is an image at 2,000x magnification, and D is an image at 3,000x magnification.

[0037] Figures 6 and 7 are TEM measurement images of the surface of the ceramic catalyst manufactured in Example 1.

[0038] The present invention improves the catalyst manufacturing unit by supporting and sintering low-cost metal oxides and hydroxides thereof suitable for the thermal decomposition of waste plastics on the surface of various zeolites, and improves the thermal decomposition and the quality of the thermal decomposition product by using a combination of metal antagonists to ensure appropriate performance.

[0039] The present invention may have a disadvantage of a decrease in the specific surface area of ​​zeolite due to the support of a reducing metal or metal salt, but it has been confirmed that the surface area characteristics are more important than the specific surface area for a pyrolysis catalyst used in atmospheric pressure pyrolysis, and therefore the present invention can increase the surface area by providing pores due to the loss generated after oxidation or combustion of activated carbon, graphite, cellulose, and coke used as a reducing agent.

[0040] The present invention can promote the decomposition and reforming of pyrolysis oil in the pyrolysis process of waste plastic by generating iron oxides (FeO, Fe3O4) having various oxidation states on the surface of zeolite and controlling the activity of aluminosilicate zeolite by impregnating alkaline earth metal oxides.

[0041] The present invention is described in more detail below.

[0042] In the present invention, in order to support reduced iron as a catalyst and surface charge modifying material on the surface of an aluminosilicate zeolite, organometallic iron (ferrocene, organic acid iron, etc.), ammonium iron (Fe), iron carbonate (Fe), nano iron oxide, etc. are used as basic starting materials. Synthetic and natural zeolites are mainly used as supports. In addition, activated carbon is used to improve the basic surface area of ​​the support, and plate-structured clay minerals are added as auxiliary materials to control the diversity of pores.

[0043] In particular, a metal deactivator was used to control the oxidation number of iron components and suppress oxidation during the oxidation process to generate reduced iron oxide.

[0044] The present invention is a reduced iron oxide-containing ceramic catalyst, which is manufactured by performing a process including: a first step of manufacturing a mixed powder and an emulsion, respectively; a second step of manufacturing a kneaded dough by mixing the mixed powder and the emulsion; and a third step of manufacturing a sintered product by performing a firing process on the kneaded dough at 500°C or lower.

[0045] The above mixed powders of steps 1 and 2 include clay minerals and aluminosilicate zeolite.

[0046] The above aluminosilicate zeolite serves as a carrier for the ceramic catalyst, and may use natural and / or synthetic zeolite. As a preferred example, it may include at least one selected from natural zeolite having a size of 150 to 350 mesh, synthetic faujasite zeolite, and synthetic A-type zeolite having a size of 150 to 350 mesh.

[0047] The above clay mineral acts as a carrier together with zeolite and improves the surface area of ​​the carrier, and may include at least one selected from activated carbon powder, ceraseite, molmoriolite, and illite. Among the above clay mineral components, the activated carbon powder rapidly combusts the activated carbon due to the combustion promoting action of iron ions, thereby rapidly generating heat and promoting calcination, and at this time, the reduction action of iron oxide due to the combustion of the activated carbon is also performed in parallel.

[0048] The emulsions of steps 1 and 2 may include at least one selected from a metal inactivator, anionic surfactant, petroleum, and methyl oleate, and preferably include a metal inactivator, anionic surfactant, and petroleum, or may include a metal inactivator, anionic surfactant, and methyl oleate.

[0049] The above metal passivator (Metal Deactivator) is a reducing agent that only participates in the reduction of iron during the oxidation calcination process of iron, and may include N,N-bis(silicylidene)-1,2-propanediamine (N,N-BIS(SALICYLIDENE)-1,2-PROPANEDIAMINE). The organic metal deactivator plays a role in preventing the oxidation of iron ions, suppresses the oxidation of iron (Fe) during the oxidation process by calcination, prevents it from being converted into iron oxide (Fe2O3), and allows various iron oxides such as FeO, Fe2O3, and Fe3O4 to exist in the ceramic catalyst. It is believed that the role of the metal deactivator, which is the main component that prevents such oxidation, is due to the influence of an alkaline nitrogen-based ligand substance.

[0050] The above anionic surfactant may be an anionic surfactant used in the art, and preferably may include sodium dioctylsulfosuccinate.

[0051] Additionally, either the mixed powder or the emulsion may further include an alkaline earth metal hydroxide, and a preferred example of the alkaline earth metal hydroxide is slaked lime.

[0052] Additionally, either the mixed powder or the emulsion may further include at least one selected from iron nitrate nonahydrate, ferrocene, reduced iron, and iron stearate.

[0053] And, the dough of the second step may contain 10 to 30 parts by weight of the emulsifier based on 100 parts by weight of the mixed powder, and preferably 12 to 26 parts by weight of the emulsifier.

[0054] In addition, the second-stage kneading material can be prepared by mixing and kneading 5 to 15 parts by weight of colloidal silica sol with respect to 100 parts by weight of the above-mentioned mixed powder in addition to the emulsion. The colloidal silica sol serves to improve the strength of the ceramic catalyst.

[0055] In addition, the second-stage dough may be prepared by mixing and kneading 3 to 15 parts by weight of at least one selected from a saturated aqueous solution of iron nitrate and a saturated aqueous solution of iron sulfate, with respect to 100 parts by weight of the above-mentioned mixed powder, in addition to the emulsion and colloidal silica sol.

[0056] Preferred examples of the composition and composition ratio of the pre-sintering dough used in the manufacture of the ceramic catalyst of the present invention are as shown in Tables 1 and 2 below.

[0057] Mixed powder composition (100 wt%) Emulsion composition Dough composition Example 1 Activated carbon powder 20 to 30 wt%, slaked lime 0.5 to 2.0 wt% and the remaining balance of 100 wt% natural zeolite 5.0 to 10.0 wt% metal inactivator, 5.0 to 11.5 wt% ferrocene, 1.0 to 4.0 wt% anionic surfactant and the remaining balance of 100 wt% petroleum mixed powder, 10 to 30 wt% emulsion Example 2200 mesh natural zeolite + activated carbon powder 10.0 to 20.0 wt%, sericite 5.0 to 12.0 wt%, iron nitrate nonahydrate 5.0 to 15.0 wt%, slaked lime 1.0 to 3.0 wt% and the remaining balance of 100 wt% natural 100 parts by weight of petroleum mixed powder containing 5.0 to 10.0 wt% of zeolite metal deactivator, 5.0 to 11.5 wt% of ferrocene, 1.0 to 4.0 wt% of anionic surfactant and 100 wt% of the remaining balance, 10 to 30 parts by weight of emulsifier and 5 to 15 parts by weight of colloidal silica sol, Example 3 10 to 20 wt% of activated carbon powder, 30 to 50 wt% of illite, 5 to 15 wt% of nano-iron hydroxide and the remaining balance of 100 wt% of synthetic faujasite 5.0 to 10.0 wt% of zeolite metal deactivator, 10.0 to 20.0 wt% of ferrocene, 1.0 to 4.0 wt% of anionic surfactant, 2.0 to 6.0 wt% of slaked lime and 100 wt% of the remaining balance For 100 parts by weight of the remaining petroleum mixture powder, 10 to 30 parts by weight of emulsifier, 5 to 15 parts by weight of colloidal silica sol, and 3 to 10 parts by weight of saturated aqueous solution of iron sulfate

[0058] Mixed powder composition (100 wt%) Emulsion composition Dough composition Example 4 Activated carbon powder 20 to 30 wt%, reduced iron 2 to 10 wt%, synthetic A-type zeolite 30 to 45 wt% and natural zeolite remaining out of 100 wt% 5.0 to 11.0 wt% of metal deactivator, 6.0 to 12.0 wt% of iron stearate, 3.0 to 7.0 wt% of anionic surfactant, 1.0 to 5.0 wt% of slaked lime and methyl oleate remaining out of 100 wt% For 100 parts by weight of mixed powder, emulsion 10 to 30 parts by weight, colloidal silica sol 5 to 15 parts by weight and saturated iron nitrate aqueous solution 3 to 10 parts by weight Example 5 Molmolyolite 15.0 to 25.0 wt%, activated carbon powder 20.0 to 25.0 wt% of synthetic A-type zeolite, 25.0 to 35.0 wt% of sericite, 3.0 to 6.0 wt% of reduced iron, 3.0 to 6.0 wt% of ferrocene, 5.0 to 10.0 wt% of slaked lime and the remaining balance of 100 wt%, 7.0 to 12.0 wt% of metal deactivator, 1.0 to 5.0 wt% of iron stearate, 3.0 to 6.0 wt% of anionic surfactant and the remaining balance of methyl oleate of 100 wt%, 10 to 30 wt% of emulsion, 5 to 15 wt% of colloidal silica sol and 3 to 10 wt% of saturated aqueous solution of iron nitrate, for example 6 10.0 to 16.0 wt% of iron stearate, 3.0 ~ 8.0 wt% and 100 wt% of the remaining natural zeolite metal inactivator 7.0 to 12.0 wt%, anionic surfactant 2.0 to 6.0 wt%, slaked lime 5.0 to 15.0 wt% and 100 wt% of the remaining petroleum mixed powder, 10 to 30 wt% of emulsifier and 5 to 15 wt% of colloidal silica sol for 100 wt%

[0059] Next, the third step is the firing process. After the dough from the second step is molded, firing is performed at a temperature of 500°C or lower, thereby synthesizing a ceramic catalyst supported with iron oxides of different oxidation states. The ceramic catalyst manufactured through the firing process contains a mixture of zero-valent, divalent, and trivalent iron oxides depending on the oxidation state, so that the iron oxide catalysts of various oxidation states are supported on the carrier. These iron oxide particles of various oxidation states can modify the surface charge of zeolite and change the pore characteristics of zeolite to adsorb various pyrolysis vapors and then promote decomposition by surface catalytic reaction. The iron oxide component contained in the ceramic catalyst manufactured by performing the 3rd step includes oxidized iron oxide of Fe2O3 and reduced iron oxide including FeO and Fe3O4, and preferably includes 15 to 85 wt% of the oxidized iron oxide and 15 to 85 wt% of the reduced iron oxide, and more preferably includes 30 to 60 wt% of the reduced iron oxide and the remaining balance of oxidized iron oxide.

[0060] By supporting these oxidized iron oxides and reduced iron oxides on the surface of a zeolite-based carrier, a thermal decomposition-promoting ceramic catalyst with improved reactivity, adsorption, and catalytic decomposition properties can be manufactured.

[0061] The reduced iron oxide-containing ceramic catalyst of the present invention can satisfy the composition ratio of Table 3 below when only the components for SiO2, Al2O3, CaOH2, CaO, Fe2O3, FeO, and Fe3O4 are shown. Table 3 below excludes trace metals and binder components.

[0062] Classification (weight%)SiO2Al2O3CaOH2CaOFe2O3FeOFe3O4Ceramic catalyst48.0 ~ 52.022.0 ~24.51.0 ~ 10.50.5 ~2.52.0 ~6.50.5 ~4.50.4 ~5.0

[0063] The ceramic catalyst of the present invention manufactured by the method described above can be used as one or more selected from waste plastic pyrolysis catalysts, petrochemical catalysts, interior tiles, building materials, air purifying materials, water treatment materials, and fertilizer materials. The waste plastic pyrolysis catalyst can be used to produce a low-temperature, high-flow point, wax-removing product through structural changes in high molecular hydrocarbons decomposed during the pyrolysis process, which is a chemical recycling process for thermoplastic waste plastic.

[0064] In addition, the waste plastic pyrolysis catalyst can be used as a catalyst for removing impurities, nitrogen, oxygen, and chlorine-based substances in polymer hydrocarbon compounds decomposed during the pyrolysis process, which is a chemical recycling process of thermoplastic waste plastic.

[0065]

[0066] To facilitate understanding of the present invention, examples will be described in detail below. However, the examples according to the present invention may be modified in various ways, and the scope of the present invention should not be construed as being limited to the following examples. These examples are provided to facilitate the understanding of the present invention by those of average skill in the art.

[0067] [Example]

[0068] Example 1: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0069] A mixed powder was prepared by mixing 74.5 wt% of polarized natural zeolite through 325 mesh, 24.5 wt% of activated carbon powder (moisture content 10%), and 1 wt% of slaked lime in a homogeneous mixer.

[0070] For 100 parts by weight of petroleum, 10.3 parts by weight of N,N-bis(salicylidene)-1,2-propanediamine as a metal inactivator, 11.5 parts by weight of ferrocene ((C5H5)2Fe), and 3.45 parts by weight of sodium dioctylsulfosuccinate as an anionic surfactant were mixed to prepare a mixed solution, which was then added to water for kneading to prepare an emulsion solution (=water dispersion solution) with a concentration of 30 wt%.

[0071] Next, 24 parts by weight of the emulsion was mixed and kneaded with respect to 100 parts by weight of the mixed powder to prepare a dough.

[0072] Next, the above dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 10 minutes, and the fired body was cooled at room temperature.

[0073]

[0074] Example 2: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0075] A mixed powder was prepared by mixing 61.9 wt% of natural zeolite polarized through a 200 mesh screen, 15.4 wt% of activated carbon powder, 10.3 wt% of iron nitrate nonahydrate (Fe(NO3)9H2O), 10.3 wt% of sericite polarized through a 325 mesh screen, and 2.1 wt% of slaked lime in a homogeneous mixer.

[0076] A mixed solution was prepared by mixing 9.2 wt% of N,N-bis(salicylidene)1,2-propanediamine as a metal deactivator, 9.2 wt% of ferrocene ((C5H5)2Fe), 2.8 wt% of sodium dioctylsulfosuccinate as an anionic surfactant, and the remaining 100 wt% of petroleum, and then adding it to water for kneading to prepare an emulsion with a concentration of 30 wt%.

[0077] A dough was prepared by mixing and kneading 12 parts by weight of the emulsion and 12 parts by weight of the colloidal silica sol with respect to 100 parts by weight of the above mixed powder.

[0078] Next, the above dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 10 minutes, and the fired body was cooled at room temperature.

[0079]

[0080] Example 3: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0081] A mixed powder was prepared by mixing 35 wt% of synthetic faujasite zeolite, 15 wt% of activated carbon powder, 10 wt% of nano-iron hydroxide (FeOOH), and 40 wt% of 325 mesh polarized illite in a homogenizer.

[0082] A mixed solution was prepared by mixing 8.1 wt% of N,N-bis(salicylidene)1,2-propanediamine as a metal deactivator, 16.1 wt% of ferrocene ((C5H5)2Fe), 1.6 wt% of sodium dioctylsulfosuccinate as an anionic surfactant, 4.0 wt% of slaked lime, and the remaining 100 wt% of petroleum, and then adding the mixture to water for kneading to prepare an emulsion with a concentration of 30 wt%.

[0083] Next, 12 parts by weight of the emulsion, 6 parts by weight of colloidal silica sol, and 6 parts by weight of a saturated aqueous solution of iron sulfate were mixed and kneaded with respect to 100 parts by weight of the above mixed powder to prepare a dough.

[0084] Next, the above dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 10 minutes, and the fired body was cooled at room temperature.

[0085]

[0086] Example 4: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0087] A mixed powder was prepared by mixing 40 wt% of polarized synthetic A-type zeolite through 200 mesh, 30 wt% of natural zeolite, 25 wt% of activated carbon powder, and 5 wt% of reduced iron in a homogeneous mixer.

[0088] A mixed solution was prepared by mixing 9.5 wt% of N,N-bis(salicylidene)-1,2-propanediamine as a metal deactivator, 9.5 wt% of iron stearate, 4.8 wt% of sodium dioctylsulfosuccinate as an anionic surfactant, 2.9 wt% of slaked lime, and the remaining methyl oleate out of 100 wt%, and then adding the mixture to water for kneading to prepare an emulsion with a concentration of 5 wt%.

[0089] A dough was prepared by mixing and kneading 12 g of the above emulsion, 6 g of colloidal silica sol, 6 g of a saturated aqueous solution of iron nitrate nonahydrate, and 100 g of the above mixed powder.

[0090] Next, the above dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 10 minutes, and the fired body was cooled at room temperature.

[0091]

[0092] Example 5: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0093] A mixed powder was prepared by mixing 9.3 wt% of polarized synthetic A-type zeolite through 200 mesh, 18.5 wt% of molmoriolite, 32.4 wt% of sericite, 23.2 wt% of activated carbon powder, 4.6 wt% of reduced iron, 4.6 wt% of ferrocene, and 7.4 wt% of slaked lime in a homogeneous mixer.

[0094] A mixed solution was prepared by mixing 10 wt% of N,N-bis(salicylidene)1,2-propanediamine as a metal deactivator, 3 wt% of iron stearate, 5 wt% of sodium dioctylsulfosuccinate as an anionic surfactant, and the remaining methyl oleate of 100 wt%, and then adding the mixture to water for kneading to prepare an emulsion with a concentration of 5 wt%.

[0095] For 100 parts by weight of the above mixed powder, 12 parts by weight of the above emulsion, 6 parts by weight of colloidal silica sol, and 6 parts by weight of a saturated aqueous solution of iron nitrate nonahydrate were mixed and kneaded to prepare a dough.

[0096] Next, the above dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 20 minutes, and the fired body was cooled at room temperature.

[0097]

[0098] Example 6: Preparation of a zeolite-based pyrolysis-promoting ceramic catalyst

[0099] 81.8 wt% of polarized natural zeolite through 200 mesh, iron stearate (C 54 H 105 A mixed powder was prepared by mixing 13.6 wt% of FeO6) and 4.6 wt% of ferrocene in a homogeneous mixer.

[0100] A mixed solution was prepared by mixing 8.9 wt% of N,N-bis(salicylidene)1,2-propanediamine as a metal deactivator, 3.6 wt% of sodium dioctylsulfosuccinate as an anionic surfactant, 10.7 wt% of slaked lime, and the remaining 100 wt% of petroleum, and then adding the mixture to water for kneading to prepare an emulsion with a concentration of 30 wt%.

[0101] A dough was prepared by mixing and kneading 12 parts by weight of the emulsion and 12 parts by weight of colloidal silica sol with respect to 100 parts by weight of the above mixed powder.

[0102] Next, the dough was dried in an atmosphere of 50°C for 10 hours, then fired at 500°C for 15 minutes, and the fired body was cooled to room temperature.

[0103]

[0104] Experimental Example 1: Component Analysis of Ceramic Catalysts

[0105] The results of analyzing the components of the ceramic catalysts manufactured in Examples 1 to 6 are shown in Table 1 below. The control group is the result of analyzing the components of an iron-inactive catalyst that was not modified.

[0106] In addition, the components in Table 4 below exclude trace metals and binder components, and only the components for SiO2, Al2O3, CaOH2, CaO, Fe2O3, FeO, and Fe3O4 are shown for comparison.

[0107] Classification (weight %) SiO2Al2O3CaOH2CaOFe2O3FeOFe3O4Control52250.20.7600Example 1522410.760.50.5Example 2492221.5323Example 3492240.751.51.5Example 4492260.7332Example 5482282324Example 64822101242

[0108] Experimental Example 2: Measurement of dewaxing rate

[0109] The ceramic catalysts manufactured in the above Examples 1 to 6 were used in a process of converting polymer compounds such as plastics into pyrolysis oil through low-temperature pyrolysis, and the inhibition rate of the production of waxy high-boiling-point hydrocarbons by cracking and isomerization reactions of high-molecular hydrocarbon polymers such as polyethylene (PE), polypropylene (PP), and polystyrene (PS) was tested using the following method.

[0110] (1) Thermal decomposition experimental conditions

[0111] The total amount of input feed raw material samples was up to 1 kg, and was applied unified as LDPE 65%, HDPE 20%, PP 13%, and PVC 1.8%.

[0112] The ceramic catalysts manufactured in Examples 1 to 6 above were used at 15 wt% based on the input amount of raw materials, and experiments were conducted in a non-catalytic environment without using a catalyst as a control group. The pyrolysis process used in the pyrolysis experiment is shown in Fig. 3, where A is a schematic diagram of a lab-scale pyrolysis process using a ceramic catalyst, and B is a schematic diagram of a lab-scale pyrolysis process without a catalyst.

[0113] The thermal decomposition test equipment was made using self-made glass.

[0114] The reaction vessel used was a round-bottom flask with a volume of 5,000 mL, and the heater was custom-made to fit the reaction vessel.

[0115] The reaction temperature was set at a maximum of 450°C.

[0116] The catalyst tower that loads the ceramic catalyst has a diameter of 40 mm and a height of 138 mm, with an effective area of ​​approximately 173 cm. 3 In order to secure and load approximately 150g of ceramic catalyst, a cooling / heating chiller capable of controlling the cooling water temperature was installed and applied to quickly respond to clogging caused by wax formation in the cooling tube during the pyrolysis process, and the basic configuration included a cooling condenser, pyrolysis oil recovery pipe, and gas absorption pipe.

[0117] Considering the thermal characteristics of waste plastic, the reactor was heated from room temperature to 180℃, 250℃, 350℃, and 450℃ in stages, and the reaction time was typically 2.5 to 3 hours to complete the reaction.

[0118] The wax (WAX) content in the pyrolysis oil obtained through pyrolysis of waste plastic was measured using HP 6890N Network GC System / SIMDIS equipment, and Supelco's Petrocol2887 was used as a column to separate hydrocarbons.

[0119] After taking 0.2 ul of pyrolysis oil, a product obtained by pyrolyzing waste plastic, the hydrocarbon composition of the pyrolysis oil was analyzed according to the ASTM D2887 test method by homogeneously mixing it with 1.5 ml of carbon disulfide, a mobile phase solvent.

[0120] According to ASTM D2887 test method, hydrocarbons (C5~C9) with boiling points of -60℃ to 130℃ are classified as naphtha, hydrocarbons with boiling points of 129℃ to 419℃ are classified as C 10 ~C 21 ) and other fuel oils, hydrocarbons (C) above 420℃ 24 (above) was defined as wax (WAX).

[0121] The high molecular weight hydrocarbon polymer raw material used was general-purpose LDPE / HDPE / PP resin.

[0122] The dewaxing rate is shown in Figure 1, and the thermal decomposition yield and hydrocarbon content for the control iron inactive catalyst and the ceramic catalysts of Examples 1 to 6 are shown in Tables 5 to 11 and Figures 2a to 2g, respectively.

[0123] Classification Substance (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Control (Iron Inactivated Catalyst) Feed (Input Raw Material) Raw Material (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 790 792 4355 Reactor Residue 100 10 --- Non-condensable Gas 110 11 ---

[0124] Classification Material (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 1 Feed (Input Raw Material) Raw Material (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 850 851 277 11 Reactor Residue 404 --- Non-condensable Gas 110 11 ---

[0125] Classification Material (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 2 Feed (Input Raw Material) Raw Material (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 830 832 56 510 Reactor Residue 606 --- Non-condensable Gas 110 11 ---

[0126] Classification Material (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 3 Feed (Input Raw Material) Raw Material (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 890 894 0 582 Reactor Residue 202 --- Non-condensable Gas 909 ---

[0127] Classification Substance (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 4 Feed (Input Raw Materials) Raw Materials (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 840 843 4642 Reactor Residue 101 --- Non-condensable Gas 150 15 ---

[0128] Classification Substance (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 5 Feed (Input Raw Materials) Raw Materials (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 790 792 96 110 Reactor Residue 505 --- Non-condensable Gas 160 16 ---

[0129] Classification Substance (Yield) Hydrocarbon Content Weight (g) Fraction (%) Naphtha (%) Light Oil (%) Wax (%) Example 6 Feed (Input Raw Material) Raw Material (LDPE+HDPE+PP+PVC) 1,000 100 --- Output (Extract) Pyrolysis Oil 880 882 5669 Reactor Residue 505 --- Non-condensable Gas 707 ---

[0130] As shown in Fig. 1, in the dewaxing rate experiment, the wax content of the pyrolysis oil was about 55% in the control group that did not use a catalyst, whereas the ceramic catalysts of Examples 1 to 6, which had a porous carrier surface treated with a reducing iron compound, had wax contents of 11%, 10%, 2%, 2%, 10%, and 9%, respectively, confirming that the dewaxing rate can be significantly improved when a ceramic catalyst, which is a porous carrier catalyst surface treated with a reducing iron compound as in the present invention, is used. In addition, as shown in Tables 5 to 11 above, in the case of the control group that did not use a catalyst, the kerosene / diesel component, which can be considered an effective component of the pyrolysis oil, was approximately 43% of the total components, but in the case of Examples 1 to 6 that used the zeolite catalyst surface-treated with the reduced iron compound of the present invention, the kerosene / diesel component, which is an effective component of the pyrolysis oil, was 77%, 65%, 58%, 64%, 61%, and 66%, respectively.

[0131] It was evaluated that the wax removal efficiency during the thermal decomposition process was the best when the calcium hydroxide (slaked lime) in the molded catalyst was at least 1 wt% to 10 wt% as the main dewaxing function, and when the ratio of reduced iron, such as FeO and Fe3O4, coexisted at 30 wt% to 60 wt% relative to the iron oxide Fe2O3 content.

[0132]

[0133] Experimental Example 3: Measurement of specific surface area, total pore volume, and average adsorption pore size

[0134] The specific surface area, total pore volume, and average adsorption pore size of the ceramic catalyst manufactured in Example 1 were measured, and the results are shown in Table 12 below.

[0135] Specific surface area (㎡ / g)Total pore volume (Single Pt)Adsorption average pore volume (Å)BETLangmuir0.137424.017380602

[0136] Conventional petrochemical catalysts require high specific surface area and BET values ​​to maximize adsorption during high-temperature and high-pressure reactions. However, waste plastic pyrolysis occurs at ambient pressure and low to medium temperatures, and surface area activity has been found to be more important than specific surface area.

[0137] Experimental Example 4: TGA, SEM, and TEM analysis of the catalyst

[0138] (1) TGA measurement was performed on the ceramic catalyst manufactured in Example 1, and the results are shown in Fig. 4.

[0139] (2) SEM and TEM analysis images of the ceramic catalyst manufactured in Example 1 are shown in FIGS. 5 to 7.

Claims

1. Step 1: Manufacturing mixed powder and emulsion respectively; Step 2: Mixing the above mixed powder and emulsion, then preparing a kneaded dough; A process including the step 3 of manufacturing a sintered product by performing a sintering process on the above dough at 500℃ or lower is performed, The above mixed powder comprises clay minerals and aluminosilicate zeolite, A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that the emulsion comprises at least one selected from a metal inactivator, an anionic surfactant, petroleum, and methyl oleate.

2. A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that in paragraph 1, the clay mineral includes at least one selected from activated carbon powder, ceraseite, molmoriolite, and illite.

3. In paragraph 1, either the mixed powder or the emulsion further contains an alkaline earth metal hydroxide, A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that either the mixed powder or the emulsion further comprises at least one selected from iron nitrate nonahydrate, ferrocene, reduced iron, and iron stearate.

4. A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that in the first paragraph, step 2 includes 10 to 30 parts by weight of the emulsion with respect to 100 parts by weight of the mixed powder.

5. A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that in the first paragraph, the second-stage kneading material is produced by further mixing and kneading 5 to 15 parts by weight of colloidal silica sol with respect to 100 parts by weight of the mixed powder.

6. A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that in paragraph 5, the dough is produced by further mixing and kneading at least one selected from a saturated aqueous solution of iron nitrate and a saturated aqueous solution of iron sulfate.

7. A method for producing a reduced iron oxide-containing ceramic catalyst, characterized in that in claim 1, the metal deactivator comprises N,N-bis(silicylidene)-1,2-propanediamine (N,N-BIS(SALICYLIDENE)-1,2-PROPANEDIAMINE).

8. A ceramic catalyst manufactured by one of the methods selected from clauses 1 to 7, wherein the catalyst-containing iron oxide component is: A ceramic catalyst containing reduced iron oxide, characterized in that it comprises 15 to 85 wt% of oxidized iron oxide of Fe2O3; and 15 to 85 wt% of reduced iron oxide containing FeO and Fe3O4.

9. In the 8th paragraph, the ceramic catalyst is characterized in that it is used as at least one selected from waste plastic pyrolysis catalysts, petrochemical catalysts, interior tiles, building materials, air purifying materials, water treatment materials, and fertilizer materials.

10. In the 9th paragraph, the waste plastic pyrolysis catalyst is a reduced iron oxide-containing ceramic catalyst characterized in that it is used for producing a low-temperature, high-flow point wax-removing product through a structural change of a high molecular weight hydrocarbon decomposed during a pyrolysis process, which is a chemical recycling process of thermoplastic waste plastic.

11. In the 9th paragraph, the waste plastic pyrolysis catalyst is a reduced iron oxide-containing ceramic catalyst characterized in that it is used as a catalyst for removing impurities, nitrogen, oxygen, and chlorine-based substances in high molecular hydrocarbon compounds decomposed during a pyrolysis process, which is a chemical recycling process of thermoplastic waste plastic.

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