TWI508779B - A method for manufacturing gasoline catalyst - Google Patents

Description

Gasoline catalyst manufacturing method

The invention relates to a method for manufacturing a gasoline catalyst, in particular to a molecular sieve catalyst for converting an oxygen compound, in particular to preparing a good skeleton first. Structure and thermal stability of the aluminum phosphate zeolite, and was added in the manufacturing process The catalytic reduction activity of the 3d transition metal reinforced molecular sieve is mixed and calcined with a bismuth aluminum molecular sieve having high thermal stability and hydrothermal stability to form a composite molecular sieve.

In 1992, Mobil Oil Company used a positively charged quaternary ammonium salt interface activator as an organic model to synthesize a M41S series mesoporous molecular sieve with a negatively charged yttrium aluminate. The mesoporous molecular sieves synthesized have a very high specific surface area and a uniform pore distribution, but most of them are crystallized pore wall structures, which may be limited in application.

The Mordenite molecular sieve is an elliptical bottle-shaped tubular structure. The pipes are connected by small holes. The ratio of bismuth/aluminum (Si/Al) is 5.0~10.0. Different from other zeolites, it has a variety of pore structures. Closed side recesses, and mainly composed of twelve unit oxygen rings, which are not suitable for the adsorption of hydrocarbons, can only be used for adsorption of small molecules such as methane or ethane.

The yttrium aluminum (ZSM type) molecular sieve structure is a monomer formed by two five-ring units, and the layers are stacked in different orders to obtain different structures. The zeolite has high thermal stability. And hydrothermal stability, used in organic solvents to catalyze the formation of hydrocarbons or organic matter that adsorbs waste or wastewater. However, although ZSM-5 molecular sieve has a high catalytic activity, it is easily restricted by the reaction of adsorption and catalyst due to the small pore size.

Aluminophosphate (AlPO ₄ -n) molecular sieve has a unique structure and properties, compared with the 矽-oxygen (Si-O) bond in the yttrium aluminum molecular sieve, aluminum-oxygen-phosphorus (Al-OP) in AlPO ₄ -n The key angle of the key changes more, including large holes, medium holes and small apertures. Therefore, the molecular sieve of AlPO ₄ -n can have more crystal structure changes and greater performance modulation, for example: (1) When the crystal framework is composed of 18 atoms, the internal pore diameter can reach 1.2. Nano (nm). (2) It has good thermal stability. For example, when the AlPO ₄ -11 molecular sieve is used at 900 ° C, the crystal structure is still not significantly damaged.

The crystal pore structure and surface properties of AlPO ₄ -n molecular sieve determine whether it can be used as a catalyst carrier. Since AlPO ₄ -n is composed of aluminum oxide tetrahedron and phosphorus-oxytetrahedron, it has an intermediate skeleton structure and has no ion exchange function. The surface does not have B acid, the L acid center is also less, generally does not have catalytic activity, because it does have good skeleton structure and thermal stability, and can be modified by various methods, such as: by ion exchange method. The atomic portion of each element replaces the phosphorus or aluminum in the skeleton, and a series of molecular sieves of aluminum phosphate are synthesized, including SAPO-n, MeAPO-n and MeAPSO-n. Substitution through a variety of different atoms not only increases the variety of molecular sieves, but also opens up new avenues for the adjustment of molecular sieve performance.

As described above, the metal aluminophosphate molecular sieve (MeAPO-n) introduces the metal cation Me ⁺ⁿ into AlPO ₄ -n via ion exchange, replacing some of the Al ions in the original skeleton, so that the uncharged neutral skeleton becomes A charged acidic backbone. Therefore, the metal cation introduced into the skeleton can carry catalytic activity, so that MeAPO-n maintains the pore structure of AlPO ₄ -n, and has good thermal stability, and improves its ion exchange performance and catalytic performance, and has a good application prospect. .

Inoue et al., 1995 (Y. Inoue, K. Nakashiro, Y. Ono, "Selective Conversion of Methanol into Aromatic Hydrocarbons over Silver-Exchanged ZSM-5 Zeolites," Microporous Materials, 4, 5, 379-383, 1995.), mentioning the use of ion exchange to displace 4d transition metal silver (Ag) ions into ZSM-5 molecular sieves for olefin dehydrogenation procedures, and found that at 750K, the conversion of aromatic hydrocarbons can reach 80%. Among them, the selectivity of benzene, toluene, C ₈ and C ₉ is 3%, 12%, 36% and 12%, but the 4d transition metal Ag ion is a noble metal, and the manufacturing cost is high.

Dubois et al., 2003 (DR Dubois, DLOBRZUT, J. Liu, "Conversion of Ethanol to Olefins Over Cobalt-, Manganese- and Nickel-Incorporated SAPO-34 Molecular Sieves," Fuel Processing Technology, 83, 203-218, 2003.), mentioning the comparison of SAPO-34 molecular sieve modified with transition metal nickel (Ni), cobalt (Co) and manganese (Mn) with the original SAPO-34 molecular sieve, it was found that the modification was carried out with or without There is little change in molecular sieve activity and C ₂ ~ C ₄ selectivity. However, the introduction of transition metals can increase the service life of molecular sieves. The molecular sieves with Mn ions have the strongest carbon deposition resistance, while the molecular sieves with Ni ions have the best service life and olefin selectivity.

Zhang et al. in the 2005 research literature (ZHZhang, XL Han, BJ Xu, ZF Yah, "Synthesis and Characterization of Binary Heteroatom Substituted Me-SAPO-11 Zeolites," Chemical Industry Times, 19, 9, 1-5 , 2005.), the mention will be different The transition metal (Co, Ti) is introduced into the phosphorus-aluminum molecular sieve to change the characteristics of the original molecular sieve. As a result, if the addition amount of titanium (Ti) is too large, it is easy to increase the non-framework in the original molecular sieve and block the pores, resulting in micro Reduced pore size and pore volume. When the addition amount of Co increases, the total pore volume ratio of the molecular sieve decreases, but the pore volume increases.

Song et al., 2006 (CMSong, CXZhao, ZFYan, "Catalyst for Coupling FCC and Aromatization to Produce High Quality Gasoline," Petroleum Processing and Petrochemicals, 37, 5, 7-10, 2006.) It is mentioned that kaolin is mixed with different proportions of additives (NiO/HZSM-5, CoAPO-11, HZSM-5/APO-11) to make catalyst, and then various catalysts are used in catalytic cracking heavy oil micro-reaction device to evaluate gasoline. And the yield of diesel. It was found that kaolin mixed with 3% and 5% of NiO/HZSM-5 catalyst was found to have a gasoline yield of about 40% and a diesel yield of about 15%, but when NiO/HZSM-5 was added. Above 5%, the yield of heavy oil will increase, while the yield of gasoline and diesel will decrease.

According to the "Divalent Metal Aluminate Catalyst" of the Republic of China Patent Application No. 75103034, the catalyst is mainly used for purifying exhaust gas derived from an internal combustion engine containing nitrogen oxides, carbon monoxide and unreacted hydrocarbons. The patent process requires heat treatment at 600~1100 ° C for 1 hour, and the added divalent metal is 28-40% of the total content, and the preparation cost is high.

The FCC (Fluidization Catalytic Cracking) method using a mesoporous catalyst, the patented molecular sieve component of the Republic of China Patent No. I369395 mainly uses aluminum hydroxide, kaolinite, sodium citrate, aluminum sulfate, sodium phosphate and Urea compound. The process is prepared by calcining at 250~850 °C, and then steaming at 650~850 °C. Have a catalyst. However, the product obtained by this method is a large pore molecular sieve.

The Republic of China Patent Publication No. I365107 "Innovative molecular sieve composition, method of preparation and application method thereof", the catalyst component of this patent mainly uses bismuth, aluminum, bismuth, ammonium salt and water, etc., mainly for preparing MCM-22 molecular sieve For hydrocarbon conversion. The process is carried out at 150~5000 rpm for 1~400 hours at 100~200 °C. However, the preparation time of this patent is too long and does not meet the economic needs.

The Republic of China Patent No. I365105 "Molecular Sieve Composition (EMM-10), the method of manufacturing the same and its use in the hydrocarbon conversion reaction", this patent is mainly applied for the preparation of MCM-22 molecular sieve with MWW topology. The method is in the form of ammonium conversion and calcination. The main components are lanthanum, aluminum and Me6-Daikui-5 salt. However, this patent does not describe the case for hydrocarbon conversion.

In addition, U.S. Patent No. 4,567,029, "Crystalline Metal Aluminophosphates", mainly uses acetic acid and zinc (Zn), Mn, magnesium (Mg) and Co to synthesize APO molecular sieves. The process was carried out by using a hydrothermal method of 100 to 200 ° C for 4 hours to 2 weeks, and then calcined at 350 ° C for 2 hours in an air atmosphere. However, the preparation time of this patent is too long and does not meet the economic needs.

The "Separation and Conversion Processes Using Metal Aluminophosphates" of U.S. Patent No. 4,801,364, which is the same as the above-mentioned U.S. Patent No. 4,567,029, the disclosure of which is hereby incorporated by reference. Hold the temperature for 1~58 hours. However, this patent also has the disadvantage that the preparation time is too long and therefore does not meet the economic needs.

US Patent No. 5,225,071, "Reforming/Dehydrocyclization" Catalysis, the patent uses any of SAPO-11, SAPO-31, SAPO-40 or SAPO-41 to bond with platinum (Pt) and chlorine (Cl), or Pt and Cl with tin ( Any of Sn), tungsten (W) or ruthenium (Re) forms a double ion bond. For oil production, the main product is n-hexane (N-Hexane, 40~75%).

No. 5,345,011, "New Manganese Catalyst for Light Alkane Oxidation", which uses the same method as described in the above-mentioned U.S. Patent No. 4,567,029 to produce molecular sieves, mainly for the production of lower alkanes, including methane, ethane, propane and natural gas. The molecular sieve (MnAPO-5, MnAPO-11, MnAPO-13, MnAPO-44) component has a Mn content of 3 to 13 wt%, a selectivity to methanol of 51%, and a conversion of methane of 4%.

US Patent No. 4,528,414, "Olefin Oligomerization", which is mainly applied to SAPO-11 and SAPO-31 containing telluride, the main products are C ₂ ~ C ₅ olefins, and SAPO-11 is the raw material for the process. The conversion rate was 86.3%, and the conversion rate of SAPO-31 to the process was 76.2%.

U.S. Patent No. 5,942,104, entitled "Alumina Source for Non-Zeolitic Molecular Sieves", which is directed to a hydrazine-containing SAPO-n (n = 3, 11, 31, 41), the main source of which is derived from hydrogen hydroxide. Aluminum (Al(OH) ₃ ) mainly refers to a molecular sieve with a pore size of 40 μm (μm), which belongs to a molecular sieve structure with a large pore size, and the conversion rate for raw materials is 78 to 93%. As stated above, the prior art does not meet the demand. Therefore, the general practitioners cannot meet the needs of the user in actual use.

The main object of the present invention is to overcome the above problems encountered in the prior art and to mention A molecular sieve catalyst suitable for converting oxygenates.

For the purpose of the above, the present invention is a method for producing a gasoline catalyst, which comprises at least: (A) adding a 3d transition metal in the process of preparing an aluminum-phosphorus molecular sieve, first setting the temperature of the solution to be between 160 and 240 After holding the temperature between °C and 43~48 hours, calcination is carried out, and the temperature is between 500 and 550 °C for 15-20 hours to obtain the aluminum phosphate molecular sieve; and (B) the α-Al2O3 sol is added. The yttrium aluminum molecular sieve is uniformly mixed with the aluminum phosphate molecular sieve and subjected to secondary calcination, and the temperature is maintained between 500 and 550 ° C for 15 to 20 hours to form a composite molecular sieve having a medium pore structure.

In the above embodiment of the present invention, the phosphorus type molecular sieve process of the step (A) comprises uniformly stirring all the raw materials at room temperature for 1 hour.

In the above embodiment of the present invention, the step (A) is to add 1.5 to 2.5 wt% of a 3d transition metal, the element of which may be selected from the group consisting of manganese (Mn), iron (Fe), cobalt (Co), and nickel (Ni). ) and zinc (Zn).

In the above embodiment of the present invention, the step (B) is carried out by adding 10 to 20 ml of an α-Al ₂ O ₃ sol as a binder.

In the above embodiment of the present invention, the aluminum-type molecular sieve type of the step (B) comprises ZSM-5.

In the above embodiment of the present invention, the mixing ratio of the aluminum phosphorus type molecular sieve to the yttrium aluminum type molecular sieve is 1:0.06 to 1 wt%.

In the above embodiment of the present invention, the crystal structure of the composite molecular sieve is a diamond type, the pore diameter is between 19.131 and 28.0442, and the surface area is between 127.427 and 235.741 m ² /g.

In the above embodiment of the present invention, the composite molecular sieve system is suitable for a composite catalyst in which methanol, dimethyl ether or a mixture thereof is converted into a high-octane gasoline, and the oxygenate conversion rate thereof is up to 100%.

11‧‧‧Step (A) Preparation of aluminum phosphate molecular sieve

12‧‧‧Step (B) Preparation of composite molecular sieves

Fig. 1 is a schematic view showing the manufacturing process of the present invention.

Fig. 2 is a schematic view showing the results of XRD detection of the molecular sieve No. 5 of the present invention.

Please refer to FIG. 1 for a schematic diagram of the manufacturing process of the present invention. As shown in the figure: the present invention is a method for producing a gasoline catalyst, which comprises at least the following steps: (A) preparing an aluminum phosphorus type molecular sieve. Step 11: in the process of preparing an aluminum phosphorus type molecular sieve, adding a range of 1.5 to 2.5 wt. % of 3d transition metal, first set the temperature of the solution between 160~240 °C for 43~48 hours, then calcination, and hold the temperature between 500~550 °C for 15~20 hours to obtain An aluminum-phosphorus molecular sieve; wherein the 3d transition metal may be selected from transition metal elements such as manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), and zinc (Zn); and (B) preparation Composite molecular sieve step 12: adding a bismuth aluminum molecular sieve and a 10-20 ml α-Al ₂ O ₃ sol as a binder, uniformly mixing with the aluminum phosphorus molecular sieve, and performing secondary calcination at a temperature between The temperature is maintained between 500 and 550 °C for 15 to 20 hours to form a composite molecular sieve with a mesoporous structure. The crystal structure of the composite molecular sieve is a rhombohedral shape with a pore diameter of between 19.131 and 28.0442 Å. Between 127.427 and 235.741 m ² /g; wherein the yttrium aluminum molecular sieve type comprises ZSM-5, and the aluminum phosphorus type The mixing ratio of the molecular sieve to the bismuth aluminum molecular sieve is 1:0.06 to 1 wt%.

The aluminum phosphorus type molecular sieve process of the above step (A) comprises uniformly stirring all the raw materials at room temperature for 1 hour. If so, a new method of manufacturing a gasoline catalyst is constructed by the above disclosed process.

Please refer to FIG. 2, which is a schematic diagram of the XRD detection result of the molecular sieve No. 5 of the present invention. As shown in the figure: When preparing, the aluminum phosphorus type molecular sieve is prepared first, and 3d transition metal is added in the process, and the temperature is maintained at 160~240°C for 43~48 hours, then calcined at 500~550°C for 15 minutes. ~20 hours; then by adding a small amount of α-Al ₂ O ₃ sol and yttrium aluminum molecular sieve for uniform mixing, and secondary calcination at 500 ~ 550 ° C for 15 ~ 20 hours, forming a mesoporous structure composite molecular sieve. The mixing ratio and the main metal component ratio of the aluminum phosphorus type molecular sieve and the yttrium aluminum type molecular sieve in this embodiment are shown in Table 1, for example.

Referring to Table 2, the results of the specific surface area analyzer (BET) show that the optimum process conditions of the present invention are molecular sieve No. 5, and the mixing ratio of the aluminum phosphorus type to the yttrium aluminum type molecular sieve is 1:1 wt%, and the synthesis temperature. The temperature is maintained at 200 ° C for 48 hours and the addition of 3d transition metal is 2 wt % of Mn ions. The composite molecular sieve synthesized by the above conditions has a pore diameter of 28.042 Å as the medium pore diameter range and a surface area of 161.617 m ² / g, and the XRD detection result of Fig. 2 shows that the crystal structure is a rhombohedron.

Further, in the present invention, a composite molecular sieve prepared by the above-described optimum conditions can be used for comparison with an oxygenate conversion reaction using a commercial molecular sieve. The experimental results are as follows:

Example 1: Conversion rate of methanol-converted gasoline using commercial ZSM-5 (Si/Al=50) molecular sieve under the reaction conditions of methanol GHSV 5g/g_molecular sieve, reaction temperature 300 ° C and reaction pressure 1 bar 83.5%, of which aromatic hydrocarbons (Aromatic Hydrocarbons) accounted for 60 vol%, olefins (Olefin) accounted for 15 vol%, n-alkanes accounted for 4.5 vol%, isoalkanes (Isoalkanes) accounted for 16.5 vol%, and cycloalkanes (Cycloalkanes) Accounting for 2.4 vol%.

Example 2: in methanol GHSV 5g / g_ molecular sieve, reaction temperature 300 ° C and reaction pressure Under the reaction condition of 1 bar, using the above molecular sieve No. 5, the added 3d transition metal is 2wt% of Mn ion, and the conversion of gasoline to gasoline is 100%, among which Aromatic Hydrocarbons accounted for 41 vol% and Olefin accounted for 7 vol%. N-alkanes accounted for 11.5 vol%, Isoalkanes accounted for 35 vol%, and Cycloalkanes accounted for 5 vol%.

Therefore, the present invention selects an aluminum-phosphorus type and a lanthanum-alumina type molecular sieve which is more suitable for use in the production of gasoline or its related products for the production of gasoline or its related products, and prepares the pore structure composite molecular sieve, and firstly prepares a good skeleton structure and thermal stability. Aluminum-phosphorus molecular sieve, adding 3d transition metal element in the process, enhancing the catalytic reduction activity of the molecular sieve, and then mixing and calcining with the aluminum-type molecular sieve with high thermal stability and hydrothermal stability, by the different characteristics of the two molecular sieves Mutual assistance to form a composite molecular sieve. Therefore, the present invention utilizes a composite molecular sieve formed by physically mixing an aluminum phosphorus type with a lanthanum aluminum molecular sieve, the pore diameter of which is a pore size of 28.042 Å, and a surface area of 161.617 m ² /g, and the crystal structure is detected by XRD. Diamond type. The composite molecular sieve of the present invention is a molecular sieve catalyst suitable for converting oxygenates, which can be converted into high-octane gasoline by using methanol, dimethyl ether or a mixture thereof under specific operating conditions (including temperature, Pressure, reflux ratio, space velocity and influent concentration), oxygenate conversion rate of up to 100%.

In summary, the present invention is a method for producing a gasoline catalyst, and the molecular sieve catalyst for converting an oxygen compound can effectively improve various disadvantages of the conventional use, and the composite molecular sieve can be used as an oxygen-containing compound to produce gasoline. The media, and the conversion rate of 100%, so that the production of the present invention can be more progressive, more practical, more in line with the needs of the user, has indeed met the requirements of the invention patent application, and filed a patent application according to law.

However, the above description is only a preferred embodiment of the present invention, and cannot be limited thereto. The scope of the present invention is intended to be within the scope of the invention as defined by the appended claims.

11‧‧‧Step (A) Preparation of aluminum phosphate molecular sieve

12‧‧‧Step (B) Preparation of composite molecular sieves

Claims (8)

The invention relates to a method for manufacturing a gasoline catalyst, which comprises at least the following steps: (A) adding a 3d transition metal in the preparation process of an aluminum phosphorus type molecular sieve, first holding the temperature of the solution at a temperature between 160 and 240 ° C. After 48 hours, calcination is carried out at a temperature of between 500 and 550 ° C for 15 to 20 hours to obtain an aluminum phosphate molecular sieve; and (B) an α-Al ₂ O ₃ sol and a yttrium aluminum molecular sieve are added. The aluminum-phosphorus molecular sieve is uniformly mixed and subjected to secondary calcination, and the temperature is maintained between 500 and 550 ° C for 15 to 20 hours to form a composite molecular sieve having a medium pore structure. The method for producing a gasoline catalyst according to the first aspect of the invention, wherein the aluminum phosphorus type molecular sieve process of the step (A) comprises uniformly stirring all the raw materials at room temperature for 1 hour. The method for producing a gasoline catalyst according to claim 1, wherein the step (A) is to add a transition metal of 1.5 to 2.5 wt%, the element of which may be selected from the group consisting of manganese (Mn) and iron ( Fe), cobalt (Co), nickel (Ni) and zinc (Zn). The method for producing a gasoline catalyst according to claim 1, wherein the step (B) is to add 10 to 20 ml of the α-Al ₂ O ₃ sol as a binder. The method for producing a gasoline catalyst according to the first aspect of the invention, wherein the aluminum-type molecular sieve type of the step (B) comprises ZSM-5. The method for producing a gasoline catalyst according to the first aspect of the invention, wherein the mixing ratio of the aluminum phosphorus type molecular sieve to the bismuth aluminum type molecular sieve is 1:0.06 to 1 wt%. According to the method for manufacturing a gasoline catalyst according to the first aspect of the patent application, wherein the crystal structure of the composite molecular sieve is a rhombus type, the pore diameter is between 19.131 and 28.0442, and the surface area is between 127.427 and 235.741 m ^{2 .} Between /g. The method for producing a gasoline catalyst according to the first aspect of the patent application, wherein the composite molecular sieve system is suitable for a composite catalyst in which methanol, dimethyl ether or a mixture thereof is converted into high-octane gasoline, and the oxygen is contained therein. The compound conversion rate can reach 100%.