Catalyst for synthesis of gasoline from dimethyl ether, method for preparing the same and method for preparing gasoline using the same

Abstract

A method of making a catalyst for gasoline reactions of dimethyl ether is disclosed, which includes reacting a silica source, an aluminum source, and a structure derivative to synthesize a zeolite sol, mixing an alcohol with an organic template to form an emulsion phase, and adding the zeolite sol to the emulsion phase to react.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2021-0055655, filed on April 29, 2021, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a catalyst for the gasoline reaction of dimethyl ether, a method for its preparation, and a method for preparing gasoline using the same, and more specifically, to a catalyst, a method for its preparation, and a method for preparing gasoline using the same, which exhibits excellent activity in the reaction of dimethyl ether to gasoline, can increase the yield of C8 in the gasoline zone, and achieve more stable catalyst operation to prevent catalyst deactivation. Background Technology

[0004] With the depletion of fossil fuels and global warming caused by CO2 emissions, the production of alternative energy sources is becoming increasingly important.

[0005] Specifically, due to international regulations on CO2 emissions, the method of producing gasoline from CO2 using methanol / dimethyl ether has attracted attention among methods to reduce CO2 emissions.

[0006] The reaction uses dimethyl ether obtained from the greenhouse gas CO2 and efficiently synthesizes gasoline for use as fuel, making it environmentally friendly, and also reduces carbon load and is therefore economical.

[0007] The reaction for producing gasoline using dimethyl ether obtained from CO2 is as follows.

[0008] [Reaction Flow 1] Methanol Synthesis from CO2 (Methanol Synthesis)

[0009] CO2 + 3H2 → CH3OH + H2O

[0010] [Reaction Procedure 2] Synthesis of Dimethyl Ether (Alcohol Dehydration)

[0011] 2CH3OH→CH3OCH3+H2O

[0012] [Reaction Flow 3] Synthesis of gasoline from dimethyl ether (DME to hydrocarbons)

[0013] CH3OCH3→hydrocarbon

[0014] The most important reaction in this three-step process is the third reaction, which involves the synthesis of gasoline from dimethyl ether. Here, the selectivity for producing high-value-added products, gasoline, and products with a carbon number of C5 or higher corresponding to the gasoline zone should be improved.

[0015] Accordingly, it is important to address the problem of Reaction Scheme 3, rather than Reaction Schemes 1 and 2, in commercialization of the method, the latter of which produces relatively lower value products and less selective adjustment of the products is required. SUMMARY

[0016] The present disclosure provides a catalyst that exhibits improved activity in a reaction of synthesizing gasoline from dimethyl ether, can increase the production of C8 in the gasoline zone, and enables more stable catalyst operation, capable of preventing catalyst deactivation.

[0017] The present disclosure also provides a method of preparing a catalyst for a gasoline reaction of dimethyl ether, in which crystals can be more effectively formed by forming an emulsion phase to introduce a magnesium alkali zeolite structure, thereby increasing reactivity due to changes in acid sites and structural characteristics, and selectivity to a specific gasoline zone.

[0018] The present disclosure also provides a method of synthesizing gasoline from dimethyl ether using the catalyst.

[0019] According to an embodiment, a method of preparing a catalyst for a gasoline reaction of dimethyl ether includes reacting a silica source, an aluminum source, and a structure derivative to synthesize a zeolite sol, mixing an alcohol with an organic template to form an emulsion phase, and adding the zeolite sol to the emulsion phase to react.

[0020] The structure derivative can be a nitrogen-containing heterocyclic compound, which includes pyrrolidine, piperidine, or a combination thereof.

[0021] The alcohol can include ethanol, propanol, butanol, heptanol, or a combination thereof.

[0022] The organic template can be an organic compound containing 15 to 30 carbons and at least one nitrogen.

[0023] The organic template can include cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate, ammonium lauryl sulfate, or a combination thereof.

[0024] The emulsion phase can be formed by mixing about 5 parts by weight to about 15 parts by weight of the alcohol based on 1 part by weight of the organic template.

[0025] The zeolite sol can be added dropwise to the emulsion phase.

[0026] The zeolite synthesis reaction can be performed at about 140°C to about 160°C for about 48 hours to about 336 hours.

[0027] The method for preparing a catalyst for a gasoline reaction of dimethyl ether can further include exchanging the Na-type zeolite produced in the zeolite synthesis reaction with a cation to prepare an NH3-type zeolite.

[0028] The method for preparing a catalyst for a gasoline reaction of dimethyl ether can further include converting the ion-exchanged zeolite into an H-type zeolite by reacting the ion-exchanged zeolite at about 450℃ to about 650℃ for about 3 hours to about 6 hours.

[0029] According to another embodiment, the catalyst for a gasoline reaction of dimethyl ether includes a zeolite having a ferrierite (FER) structure and a ZSM-5 structure.

[0030] In the zeolite, the ferrierite (FER) structure and the ZSM-5 structure can be mixed at a molar ratio of about 1:0.01 to about 1:2.

[0031] The Si / Al molar ratio of the zeolite can be about 5 to about 15.

[0032] According to another embodiment, the method for preparing gasoline includes preparing gasoline through a gasoline reaction of dimethyl ether using a catalyst.

[0033] The catalyst shows excellent activity in a reaction for synthesizing gasoline from dimethyl ether, can increase the production of C8 in a gasoline zone, and achieves more stable catalyst operation to prevent catalyst deactivation.

[0034] The method for preparing a catalyst for a gasoline reaction of dimethyl ether can more effectively form crystals by forming an emulsion phase to introduce a ferrierite structure, so that reactivity can be improved and selectivity to a specific gasoline zone can be improved due to changes in acid sites and structural characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1A 、 Figure 1B and Figure 1C are graphs showing the conversion of dimethyl ether and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 1.

[0036] Figure 2A 、 Figure 2B and Figure 2C are graphs showing the conversion of dimethyl ether and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 2.

[0037] Figure 3A 、 Figure 3B and Figure 3C are graphs showing the conversion of dimethyl ether and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 3.

[0038] Figure 4A 、 Figure 4B and Figure 4C are graphs showing the conversion of dimethyl ether and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 4.

[0039] Figure 5A , Figure 5B and Figure 5C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 5.

[0040] Figure 6A , Figure 6B and Figure 6C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 6.

[0041] Figure 7A , Figure 7B and Figure 7C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Example 7.

[0042] Figure 8A , Figure 8B and Figure 8C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Comparative Example 1.

[0043] Figure 9A , Figure 9B and Figure 9C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Comparative Example 2.

[0044] Figure 10A , Figure 10B and Figure 10C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Comparative Example 3.

[0045] Figure 11A , Figure 11B and Figure 11C are graphs showing the dimethyl ether conversion and the selectivity pattern to C1 to C5 or higher of the catalyst prepared in Comparative Example 4.

[0046] Figure 12 are SEM photographs showing the zeolite catalysts prepared in Examples 1 to 3.

[0047] Figure 13 is a graph showing the X-ray diffraction (XRD) analysis results of the zeolite catalyst measured in Experimental Example 3.

[0048] Figure 14 is a graph showing the TPD analysis results of the zeolite catalyst measured in Experimental Example 4.

[0049] Figure 15 is a graph showing analysis results of specific surface areas of zeolite catalysts measured in Experimental Example 5. DETAILED DESCRIPTION

[0050] Advantages and features of the present disclosure and methods of accomplishing the same will become apparent to those of ordinary skill in the art from the embodiments described below in conjunction with the accompanying drawings. However, the embodiments can not be limited to the exemplary embodiments disclosed below. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. Also, unless explicitly defined, the terms should not be ideally or excessively interpreted.

[0051] In addition, unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0052] In addition, the singular includes the plural unless otherwise mentioned.

[0053] The method for preparing a catalyst for gasoline reaction of dimethyl ether according to an embodiment includes synthesizing a zeolite sol, forming an emulsion phase, and adding the zeolite sol to the emulsion phase to perform hydrothermal synthesis.

[0054] The zeolite sol can be synthesized by reacting a silica source, an aluminum source, and a structure derivative.

[0055] The silica source can include a silica sol, a silica gel, a silica hydrogel, silicon hydroxide, fumed silica, precipitated silica, sodium silicate, tetraalkyl orthosilicate, or a combination thereof.

[0056] The aluminum source can include sodium aluminate (NaAlO2), AlCl3, Al2(SO4)3, aluminum hydroxide (Al(OH)3), kaolin, clay, or a combination thereof.

[0057] The structure derivative can be a heterocyclic compound, and can include, for example, pyrrolidine, piperidine, or a combination thereof.

[0058] For example, the silica source, the aluminum source, and the structure derivative can be added to and reacted in an aqueous alkali hydroxide solution including sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, or a combination thereof to synthesize the zeolite sol.

[0059] The silica source and the aluminum source can be added in a molar ratio of about 5: 1 to about 15: 1, for example, about 10: 1. When the molar ratio of the silica source and the aluminum source is less than about 5, the amount of acid sites in the reaction can decrease and the reactivity can become poor. The strength of the acid sites can decrease or the crystallinity can decrease. When the molar ratio of the silica source and the aluminum source exceeds about 15, in addition to forming acid sites, aluminum can be added to the magnesium-based zeolite or ZSM5-5 structure, thereby decreasing the strength of the acid sites or decreasing the crystallinity.

[0060] The structure derivative can be added in an amount of about 0.5 molar parts to about 15 molar parts, for example, about 0.9 molar parts to about 10 molar parts, based on 1 molar part of the silica source and the alumina source. If the amount of the structure derivative is less than about 0.5 molar parts, a magnesium-based zeolite structure cannot be formed but only a ZSM-5 structure can be formed. If the amount of the structure derivative exceeds about 15 molar parts, the amount of acid sites generated after synthesis can decrease, thereby affecting the reactivity of the catalyst.

[0061] As an example, the zeolite sol synthesis reaction can be performed by rotating at about 300 rpm to about 800 rpm at about 15 °C to about 40 °C and reacting for about 1 day to about 2 days. When the zeolite sol synthesis reaction temperature is less than about 15 °C, the size and the crystallinity of the zeolite sol formed can decrease, and when it exceeds about 40 °C, the size of the zeolite sol can excessively grow. When the zeolite sol synthesis reaction time is less than about 1 day, the crystallinity of the zeolite sol can be low, and when it exceeds about two days, the size of the zeolite sol can become too large.

[0062] The emulsion phase is formed by mixing an alcohol with an organic template.

[0063] The alcohol can include ethanol, propanol, butanol, heptanol, or a combination thereof.

[0064] The organic template can be an organic compound including 15 to 30 carbons and at least one nitrogen, for example, cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate, ammonium lauryl sulfate, or a combination thereof.

[0065] The emulsion phase can be formed by mixing about 5 parts by weight to about 15 parts by weight of the alcohol based on 1 part by weight of the organic template, for example, by mixing about 6 parts by weight to about 8 parts by weight of the alcohol based on 1 part by weight of the organic template. When the amount of the alcohol is less than about 5 parts by weight, the emulsion phase can not be sufficiently generated during the emulsion formation, and when it exceeds about 15 parts by weight, the emulsion phase is not generated during the emulsion formation and interferes with the action of the organic template, so that a third crystal structure can occur.

[0066] The zeolite sol is added to the emulsion phase and reacted to synthesize a zeolite.

[0067] For example, the zeolite sol can be added dropwise to the emulsion phase using a syringe pump or the like.

[0068] The zeolite synthesis reaction can be performed by hydrothermal synthesis at about 140°C to about 160°C for about 48 hours to about 336 hours, for example, by hydrothermal synthesis at about 140°C to about 160°C for about 96 hours to about 168 hours. When the zeolite synthesis reaction temperature is less than about 140°C, the formed crystals are too small and the crystallinity can be reduced, and when it exceeds 160°C, the crystal growth can be excessive and the crystal size can be increased. When it is less than about 48 hours, the crystal size can be too small due to little crystal growth, and when it exceeds about 336 hours, structural problems can occur due to excessive crystal growth.

[0069] At this time, the zeolite synthesized in the emulsion phase can be a Na-type zeolite, and can further include ion exchange by exchanging it with a cation to prepare an NH3-type zeolite.

[0070] For example, the Na-type zeolite is immersed in an aqueous solution of ammonium nitrate (NH4NO3) and stirred at about 60°C to about 80°C for about 3 hours or more, and the process is repeated 3 to 6 times to ion exchange into an NH4 + type, thereby preparing an NH3-type zeolite.

[0071] In addition, the ion-exchanged zeolite can be converted into an H-type zeolite by calcination at about 450°C to about 650°C for about 3 hours to about 6 hours. When the calcination reaction temperature is less than about 450°C, the removal of ammonium ions is not sufficient, and OH bonds (Brønsted acid sites) can not be sufficiently generated, and when it exceeds about 650°C, the zeolite structure itself can collapse. When the calcination reaction time is less than 3 hours, the removal of ammonium ions is not sufficient, and OH bonds (Brønsted acid sites) can not be sufficiently formed, and when it exceeds about 6 hours, the zeolite structure itself can collapse.

[0072] In the method for preparing a catalyst, a zeolite having both a ferrierite (FER) structure and a ZSM-5 structure can be synthesized by synthesizing a zeolite using an alcohol in an emulsion phase. At this time, the acid properties and the crystal structure of the zeolite can be changed by changing the kind and amount of the alcohol and the synthesis time. Accordingly, the gasoline reactivity of dimethyl ether can be improved and the selectivity to a specific gasoline region can be improved.

[0073] The catalyst for the gasoline reaction of dimethyl ether according to another embodiment includes a zeolite having a ferrierite (FER) structure and a ZSM-5 structure, which is prepared by the above preparation method.

[0074] When ZSM-5 zeolite is applied to the gasoline reaction of dimethyl ether, the selectivity to C8, which is a key component in the gasoline field, is not high. In addition, it is known that ferrierite (FER) zeolite has no reactivity in the gasoline reaction of dimethyl ether. However, a zeolite having both ferrierite (FER) structure and ZSM-5 structure has excellent reactivity in continuous gasoline production and has very good selectivity to C8.

[0075] For example, in a zeolite including ferrierite (FER) structure and ZSM-5 structure, the ferrierite (FER) structure and the ZSM-5 structure can be mixed at a molar ratio of about 1:0.01 to about 1:2, for example, about 1:0.05 to about 1:1. When the molar ratio of the ZSM-5 structure and the ferrierite (FER) structure is less than about 0.01, since the ZSM-5 structure, which is high in stability in the DTG (DME to gasoline) reaction, is small, the deactivation of the catalyst can be large. When it is greater than about 2, the selectivity to C5 or higher products, which is an advantage of the presence of a large-sized ring, can be reduced.

[0076] In addition, the Si / Al molar ratio of the zeolite can be about 5 to about 15, for example, about 9 to about 11. When the Si / Al molar ratio of the zeolite is less than about 5, the amount of acid sites, which are reaction points, can be too small, and the reactivity can be severely reduced. When it is greater than about 15, aluminum is excessively embedded in the ferrierite structure, and thus the strength of the acid sites can be weakened or the ferrierite characteristic crystal itself can not be formed.

[0077] Hereinafter, specific embodiments of the present disclosure are described. However, the embodiments described below are for illustrative purposes only, and the scope of the present disclosure is not limited thereto.

[0078] Experimental Example 1: Synthesis method of zeolite

[0079] 1) Synthesis of zeolite sol in which a silica source, an aluminum source, and a structure derivative are mixed

[0080] The basic silica solution and the structure derivative of pyrrolidine were stirred for 1 hour. The solution was further continuously stirred for 1 hour, and the aluminum source was added thereto, and then further continuously stirred for 11 hours. Here, the ratio of Si added at the beginning and Al added after stirring was adjusted to synthesize a final product having a Si / Al molar ratio of 10.

[0081] 2) Formation of emulsion phase and synthesis of zeolite

[0082] The CTAB and the alcohol were mixed to form an emulsion phase, and the zeolite sol was added dropwise to the emulsion phase by using a syringe pump.

[0083] Subsequently, hydrothermal synthesis was performed and continued for 4 to 7 days at 160°C. After 4 to 7 days, the resultant product was washed with distilled water, dried at 60 to 110°C overnight, and calcined at 550°C for 6 hours. At this point, the synthesis of the Na-type zeolite was completed.

[0084] Ion exchange was repeated 6 times by using 1M NH4NO3 at 80°C for 3 hours. After ion exchange, the resultant product was calcined at 550°C for 3 hours, and the synthesis of the catalyst was completed.

[0085] The synthesized catalyst was named E-FER(x1, y, z)-T1 to T2, or E-ZSM-5

[0086] (x 2,3,4 , y, z)-T1 to T2. Here, x indicates the type of alcohol used to form the emulsion phase, x1 indicates propanol, x2 indicates ethanol, x3 indicates butanol, x4 indicates heptanol, y indicates the amount of alcohol, z indicates the number of synthesis days, and T1 to T2 indicate the reaction temperature range. In the naming, E-FER or E-ZSM-5 was selected according to the XRD crystallinity.

[0087] Example 1

[0088] The E-FER(propanol, 0.43, 4)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0089] Example 2

[0090] The E-ZSM-5(ethanol, 0.43, 4)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0091] Example 3

[0092] The E-ZSM-5(ethanol, 0.43, 4)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0093] Example 4

[0094] The E-FER(propanol, 0.43, 7)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0095] Example 5

[0096] The E-ZSM-5(ethanol, 0.43, 7)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0097] Example 6

[0098] The E-ZSM-5(butanol, 0.27, 7)-330 to 290 catalyst was prepared according to the same method as in Experimental Example 1.

[0099] Example 7

[0100] E-ZSM-5 (heptanol, 0.27, 7)-330 to 290 catalysts were prepared according to the same method as in Experimental Example 1.

[0101] Comparative Example 1

[0102] A commercially available ZSM-5 zeolite was used as a catalyst.

[0103] The catalyst used in Comparative Example 1 is referred to as CZSM-5-T1 to T2. Here, T1 to T2 are reaction temperatures and can be 330℃, 320℃, 310℃, 300℃, and 290℃.

[0104] Comparative Example 2

[0105] A catalyst prepared by mixing a commercially available ZSM-5 zeolite and a commercially available ferrierite in a weight ratio of 1:1 was used.

[0106] The catalyst used in Comparative Example 2 is referred to as VFER and CZSM-5 (1:1 wt% mixture)-T1 to T2. Here, T1 to T2 are reaction temperatures and can be 330℃, 320℃, 310℃, 300℃, and 290℃.

[0107] Comparative Example 3

[0108] A commercially available ferrierite was used as a catalyst.

[0109] The catalyst used in Comparative Example 3 is referred to as VFER-330. Here, 330 indicates a reaction temperature (℃).

[0110] Comparative Example 4

[0111] A nanosheet ferrierite zeolite was synthesized and used as a catalyst.

[0112] The catalyst used in Comparative Example 4 is referred to as NSFER-310. Here, 310 indicates a reaction temperature.

[0113] Experimental Example 2: Gasoline reaction experiment of dimethyl ether

[0114] A catalyst including a synthesized zeolite was used for a gasoline reaction of dimethyl ether, that is, a C1 to C5 or higher hydrocarbon production reaction, and particularly a reaction in a gasoline production zone.

[0115] 0.4 g of a zeolite catalyst was put into a fixed bed reactor, and then experiments were performed by changing reaction conditions while a mixed gas was introduced thereto at a predetermined flow rate.

[0116] Before the reaction, the catalyst was pretreated. For example, the pretreatment was performed by increasing the temperature to 400°C under a nitrogen atmosphere for 2 hours to remove foreign substances such as water molecules present in the zeolite.

[0117] After the pretreatment, the gasoline reaction was performed at a reaction temperature of 330°C, 320°C, 310°C, 300°C, and 290°C for 5 hours while passing a mixed gas of dimethyl ether:nitrogen having a molar ratio of 5:95 into the same at a space velocity of 4400 L / kg 催化剂 / hour to 5000 L / kg 催化剂 / hour.

[0118] The composition of the product obtained during the reaction was analyzed by gas chromatography, and the analysis results were used to calculate the dimethyl ether conversion rate, the selectivity to C1 to C5 or higher, etc. The results of the reaction are shown in Table 1 and FIGS. 1 to 11.

[0119] Table 1

[0120]

[0121]

[0122]

[0123] Referring to Table 1 and FIGS. 1 to 11, the catalysts according to Examples 1 to 7 exhibited reduced selectivity to the C1 to C4 region, increased selectivity to the gasoline region (C5 or higher), and high selectivity at a lower temperature, particularly, increased selectivity to C8 products affecting octane number, which is a key in gasoline, compared to the catalysts according to Comparative Examples 1 and 2.

[0124] Accordingly, unlike the conventional commercially available magnesium base zeolite and the commercially available ZSM-5 zeolite, the zeolite catalyst synthesized after forming an emulsion phase exhibited increased selectivity to the gasoline region (C5 or higher) and C8.

[0125] Experimental Example 3: Structural analysis of zeolite

[0126] The zeolite catalysts according to Examples 1 to 3 were subjected to SEM analysis, and the results are shown in Figure 12 .

[0127] Through the SEM analysis, it was visually confirmed whether the crystal was changed according to the synthesis conditions, and in addition, the synthesized catalyst had a zeolite structure.

[0128] In addition, the zeolite catalyst was subjected to X-ray diffraction analysis (XRD), and the results are shown in Figure 13 .

[0129] Referring to Figure 13The zeolite catalysts according to Examples 1 to 7 have a composite structure of ZSM-5 and ferrierite, wherein the zeolite catalysts according to Examples 1 and 4 have a dominant ferrierite structure in the XRD results, and the zeolite catalysts according to Examples 2, 3, 5 and 7 have a dominant ZSM-5 structure in the XRD results. In other words, the X-ray diffraction analysis indicates that the unique framework structures of ZSM-5 and ferrierite are produced in a composite manner under various synthesis conditions.

[0130] Accordingly, in order to make the zeolite to include the ferrierite structure and the ZSM-5 structure in a composite manner, it is important to follow appropriate conditions in each synthesis process, and in particular, the type of alcohol, the synthesis time and temperature, and the weight ratio of the organic template to the alcohol should be within an appropriate range.

[0131] Experimental Example 4: Analysis of acid sites of the zeolite catalyst

[0132] The zeolite catalyst was subjected to TPD analysis, and the results are shown in Figure 14 .

[0133] TPD analysis uses ammonia, which is a basic material, and is thus called NH3-TPD. Ammonia is a basic material, and thus is adsorbed to acid sites present in the zeolite framework. Ammonia has a very small molecular size, and thus can be adsorbed to all acid sites in the zeolite.

[0134] TPD can not completely distinguish Bronsted acid sites and Lewis acid sites, but in the TPD results, peaks considered to be strong acid can be considered to be Bronsted acid sites, and other acid sites are considered to be Lewis acid sites or defect sites.

[0135] Experimental Example 5: Analysis of specific surface area of the zeolite catalyst

[0136] N2adsorption, which is the specific surface area analysis of the synthesized zeolite catalyst, was performed, and the results are shown in Figure 15 .

[0137] Referring to Figure 15 , the zeolite in which ZSM-5 is dominant in the XRD analysis results exhibits a larger specific surface area than a commercially available ZSM-5. Similarly, the zeolite in which ferrierite is dominant has a larger specific surface area than a commercially available ferrierite.

[0138] While the disclosure has been described in connection with what is presently considered to be the practical exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method for preparing a catalyst for the gasoline reaction of dimethyl ether, comprising the following steps: To synthesize zeolite sol by reacting silica source, aluminum source and structural derivative; Alcohols are mixed with organic templates to form emulsion phases; and The zeolite sol is added to the emulsion phase to carry out a zeolite synthesis reaction; The catalysts mentioned above include zeolites having magnesium alkali zeolite FER structures and ZSM-5 structures; The structural derivatives mentioned above are nitrogen-containing heterocyclic compounds, including pyrrolidine, piperidine, or combinations thereof; The organic templates mentioned therein include hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, ammonium lauryl sulfate, or combinations thereof.

2. The method according to claim 1, wherein the alcohol comprises ethanol, propanol, butanol, heptanol or a combination thereof.

3. The method of claim 1, wherein the emulsion phase is formed by mixing 5 to 15 parts by weight of an alcohol based on 1 part by weight of the organic template.

4. The method of claim 1, wherein the zeolite sol is added dropwise to the emulsion phase.

5. The method according to claim 1, wherein the zeolite synthesis reaction is carried out at 140°C to 160°C for 48 hours to 336 hours.

6. The method according to claim 5, further comprising exchanging the Na-type zeolite produced in the zeolite synthesis reaction with cations to prepare NH3-type zeolite.

7. The method according to claim 6, further comprising converting the NH3-type zeolite into H-type zeolite by reacting the NH3-type zeolite at 450°C to 650°C for 3 to 6 hours.

8. A catalyst for the gasoline reaction of dimethyl ether, prepared by the method according to claim 1, and Zeolites including those with magnesium-alkali zeolite FER structure and ZSM-5 structure.

9. The catalyst according to claim 8, wherein the magnesium alkali zeolite FER structure and the ZSM-5 structure are mixed in a molar ratio of 1:0.01 to 1:2 in the zeolite.

10. The catalyst according to claim 8, wherein the Si / Al molar ratio of the zeolite is 5 to 15.

11. A method for preparing gasoline by reacting dimethyl ether with gasoline, using the catalyst according to claim 8.

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