TW272146B - The preparation of eggshell catalysts having selective reversal or oxidation reaction - Google Patents

Description

^ 2146 A6 B6… Amendment date / 84 · 4. 1 7 Supplement V. Description of the invention (1) Projects such as oil refining and petrochemical industry have extensively researched and applied unevenly distributed active metals that are thinner than porous carriers on. It has been confirmed by theory and experiment. Its advantages are increased productivity and selectivity, reduced thermal sensitivity, resistance to poisoning and activity decline, and increased wear resistance. According to the literature of Ind. Eng. Chem. Prod. Res. Dev 1981 vol 20, P 439, the distribution of non-uniform active metals can be divided into four categories: ('丨) uniform metal distribution, usually used for low catalytic activity and no quality Resist the reaction. (f) Gold ^ is distributed in the outer layer of the support (egg-shell-like), which is usually used for rapid reaction and has a selectivity and yield to the desired product. (3) The metal is distributed inside the support (egg yolk), usually used in fluidized bed or moving bed. The outer layer of the catalyst is easy to be worn or poisoned. (4) The metal fraction is between the eggshell and egg yolk (protein), and its application range is between the eggshell and egg yolk. The particles have mass transfer resistance inside and the outer layer is easily poisoned or worn. At present, eggshell catalysts have been widely used in industrial selective hydrogenation reactions (for example, hydrogenation of acetylene to ethylene, pyrolysis of gasoline to hydrogenate dienes to monoenes, etc.), and selective isomerization reactions (for example, for α- olefins into /?-〇lefins, etc.), selective oxidation reaction (for example, the reaction of ethylene into ethylene oxide, S〇2 oxidation reaction, CO oxidation reaction, etc.). The use of eggshell catalysts in the above reactions can increase the yield and selectivity of the desired product. Especially for Consecutive Reactions: A—> B—According to

Chem. Eng. Sci. Vol. 27, 1972, P 227 and Chem. Eng. Sci. Vol. 29, 1974, P 1473. It has been confirmed that eggshell catalysts can increase the yield of desired product B and Choice rate. According to the literature of J. of Cliei Eng. Of Japan, vol. 22, Νο · 3, 1989, P 287, it was confirmed that the selective hydrogenation of acetylene to ethylene (main product), the selectivity order of ethylene is Ni / Al2 〇3 The nickel of the catalyst is distributed on the thin layer of eggshell / Al2〇3 (Eggshell of thin layer) > thick layer of eggshell (Eggshell of thick layer) >, evenly divided (Uniform)> egg yolk ( Eggyolk). The current patents and literature on manufacturing uneven metal distribution on the carrier are as follows: According to U.S.

Patents 3,259,454 and 3,259,589 (July 5,1966) and ER Becker et al. &Quot; in Preparation of CatalystsII: Proceedings of the Second ------------------------ Install ------ order- ^ (please read the precautions on the back before writing the form page) Printed by the β-Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. The paper size is in accordance with China National Standard (CNS) A4 specifications (210 X 297 Gong *) 5. Description of the invention (2)

International Sympogereous Catalysts 'Elsevier, Amsterdam, 1979, P 159' is the use of H2PtCl6 and citric acid co-impregnation to produce a variety of uneven platinum distribution on the spherical alumina support, its reproducibility experimental error is about 10%. According to the literature of J. Cata ,, v〇l. 43, 1976, P 200, the pioneers such as (^ 〇3, (NH4) 2Cr2〇7, Cr (D3) 3, and Cu (N〇3) 2 were used Materials, using various impregnation techniques to produce Cr and cu metals in various states with uneven distribution on the spherical A1 carrier. According to the literature of j. Catal., Vol. 63, 1980, P 425, adding HC1, Many salts such as NaBr in H2PtCl6 impregnated solution can correct Pt to be in nine different states and unevenly distributed in spherical A 丨 2〇3 support. According to the above literature and patent information, it is necessary to produce uneven metal distribution on the carrier Medium: Both inorganic metal salts and other salts are used, and the PH value is used to control the metal thickness and position. The disadvantages of these methods are: (1) The anions in the inorganic salts will remain on the carrier and need to be heated through the south. The anions are removed by burning, and some anions are not easy to be removed, such as (1), S〇4-2, etc., if the catalyst needs to be reduced to metal state by hydrogen to be active and react, these anions may react with hydrogen to form H (: 丨He Liu 4, these acidic substances will be ^ 1⑵ The previous literature and patented methods are very Metal thickness and accurately control the weight percent of eggshell catalyst.

Sn, V ,, dissolved in a solvent or the like under heating or normal temperature) or after the agent has been impregnated with the catalyst under varying degrees (sister change impregnation solution_type and concentration, etc.), can be modified by ^ 72146 184 A6 B6 Printed by the Ministry of Economic Affairs, Central Standardization Bureau, S Industry and Consumer Cooperatives V. Description of the invention (^) To accurately control the thickness of single or multiple metal eggshells and the metal content and metal dispersion of the catalyst after preparation . Example 1: Eggshell-like and uniformly distributed Pd / Al2〇3 catalyst in the selective hydrogenation of isoprene, the effect on conversion rate, selectivity and life span Step 1: Preparation of 0.2wt% Pd / Al2〇3 The catalyst is evenly distributed: Weigh 0.1523 g Pd (NH3) 4 (N〇3) 2, whose purity is 36.04wt% Pd, dissolve in 50mL deionized water, weigh 10.045 8-6] 丨 2〇3 ( Spherical particle diameter 2 and its surface area is 82.41112 / ^, pore volume is 0.570 cc / g) 'Place Al2〇3 in the solution, shake at 100 rpm: stir for 3 hours, filter and dry at 100 ° C 1 Hour, the temperature is increased from normal temperature to 350 ° C at a temperature rise rate of 10 ° C / minute and held for 6 hours. The catalyst sample was subjected to elemental analysis to obtain 0.2wt% Pd, and the Electron Probe Microanalyser (ΕΡΜΑ) analysis measured the Pd metal distribution to be uniformly distributed as shown in Figure 1. Step two: Preparation of 0.2wt% Pd / Al2〇3 palladium eggshell catalyst: Weigh 0.1068g? () ((: 113〇00) 2, its purity is 47 \ ^? (1, soluble in 150 In toluene, weigh 25.048 g e-Al2〇3, put Al2〇3 into the solution, the subsequent processing steps are the same as step one, and its catalyst sample is analyzed by EPMA to determine the distribution of Pd metal as eggshell distribution as shown in Figure 2. Step 3: Eggshell-like and uniformly distributed catalysts In the selective hydrogenation of isoprene, the effect on conversion rate, selectivity and lifespan: The catalytic activity of both catalysts is tested using 10 wt% isoprene in The selective hydrogenation reaction was carried out in n-heptane solvent, and the experiment was conducted in a downflow continuous fixed bed reactor system. The reactor is a vertical stainless steel tube with an inner diameter of 2.2 cm and an inner volume of 94 mL. The furnace uses an electric heating system and a piD temperature controller to control the reaction temperature. The reaction product is condensed at a temperature of -3 ° C using a refrigeration cycle tank, and then samples are taken at intervals to analyze its composition by GC. The mass balance is greater than 97¾, indicating that there is no problem with the system test response. The response The operating conditions are as follows: A. Use about 1 gram of catalyst to mix 25mL of 0.4-0.6mm spherical glass beads and fill it in the middle of the reactor. Then fill the top and bottom of the reactor with 0.4-0.6rnm spherical glass beads. (Please first Read the precautions on the back and write this page again.. Installed. · The size of the paper in line with the Chinese National Standard (CNS) A 4 specifications (210 X 297 mm) 272146 Amendment k 4. 1 7 Supplement A6 B6 Central Ministry of Economic Affairs Printed by Beigong Consumer Cooperative of the Bureau of Standards 5. Description of the invention (4) B. Leak test with nitrogen at 440 Psig pressure. C. With a hydrogen flow rate of 1.2 L (NTP) / h at 100 ° C, 410 Psig will PdO is reduced to Pd for 10 hours. D. After the reduction is completed, the temperature is reduced to a reaction temperature of 44 ° C. With a weight space flow rate = 18h-1 (g of feed / hg of Catalyst), P 2 30 atm, T 2 44〇C, H2 / lsoprenemolarratio = 2.262: ^; ft & iio E. Its simple reaction system is as follows: £ -► 3M1B -η IP-► 2M2B-^ IC5 T► 2M1B-^ where IP: Isoprene (isoprene Ene) 3M1B: 3-methy bu 1-butene (3 methyl 1 butene) 2M2B: 2iethy bu 2-butene (2 methyl 2 butene) 2M1B: 2-methyl-bu butene (2 Methyl 1 butene) IC5 ·· Isopentane (Isopentane) Isoprene produces partial hydrogenated products 2MIB and 3MIB via Bu 2 hydrogen addition, however the formation of 2M2B can be via Bu 4 hydrogen addition and from 2M1B and 3MIB Double bond shift isomerization reaction. Among them, 2MIB and 2M2B are the main feedstock of TAME (tertiary amyl methyl ether) process. Then the undesirable product IC5 is further hydrogenated through isoprene (the MB symbol after isopentens, which is the sum of 3MIB, 2MIB and 2M2B) to produce 0. Figure 3 (a) and (b) represent eggshell shape The concentration of the main products of isoprene hydrogenation, 2MIB, 3MIB, 2M2B and IC5, which are both homogeneous catalysts, varies with the reaction time (Time on Stream). The part of Figure 3 in which isoprene changes with reaction time is taken and plotted as Figure 4. From the results of Figure 4, it is known that the eggshell catalyst has higher activity (ie conversion rate) and lower value than the homogeneous catalyst Activity decline rate. We have used the two waste catalysts after the reaction as this paper. The standard of the paper is applicable to China's national private standards (CNS> A 4 specifications (21〇X 297 male wear) -----.---------- -------- ^ ------ tr ---- Marry (please read the precautions on the back before writing this page) 272146 A6 B6, invention description (5) (please read the back page first Matters needing attention to write this page again}

Differential Scanning Calorimeter (DSC) analysis and extraction of the waste catalyst polymer harder cokeri with toluene, concentration, and GC / mass (Gas Chromatography / mass spectrometer) analysis, respectively, to obtain Figures 5 and 6 and Table 1 . Figure 5 shows the eggshell-like and homogeneous catalyst. Both have the same main peak at a temperature of 30.8 ° C (representing softer coke). In addition, the eggshell catalyst has a temperature of 408 ° C (representing harder coke) The temperature of the homogeneous catalyst is 455 ° C. From Figure 6 and Table 1, the retention time of the GC is less than 20.4 points. Both have the same softer coke. When the retention time is greater than 20.4 points, only the homogeneous catalyst has hard carbon (harder) coke), the evidence from DSC and GC / mass patterns can help us understand why eggshells have a lower rate of activity decline than homogeneous catalysts. The concentration of the main product isoprene (MB) and the supersaturated hydrogenated product isopentane (IC5) versus reaction time are shown in Figures 7 and 8, respectively. It is obvious that eggshells are more likely to generate more major than homogeneous catalysts. The product isopentene and the less undesirable product isopentane. We define the isoprene selectivity (sMB) as: (2MIB + 2M2B + 3M1B) total moles ... SMB =-x \ m Molar numbers converted by the IP reaction Figure 9 shows the sMB pair of the two catalysts The change of the reaction time obviously shows that the eggshell-like ratio is higher than the selection rate of catalysts printed by the 8th Industrial Cooperative Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs. Because 2M1B and 2M2B are the main feeds for the TAME process, Figure 10 shows the changes in the selectivity of the two catalysts, their main products 2M1B and 2M2B, to the reaction time. Obviously, the eggshell shape has higher 2M2B selection rate. Based on the above experimental results, for the selective hydrogenation of isoprene, eggshell catalysts are better than homogeneous catalysts in terms of isoprene conversion rate, isoprene selectivity and catalyst life.

W121.U Shirt 4 4.1 *: Amend I year month day A6 I supplement β6 V. Description of invention (G) Printed by the Ministry of Economic Affairs Central Standards Bureau Beigong Consumer Cooperatives Table 1: Product of two types of catalysts, eggshell and uniform Detailed composition of the carbon precursor Carbon deposit precursor homogeneous catalyst eggshell catalyst RT (min) RA * RT (min) RA * 1. 2, 4 dimethylheptane 13.058 0.936 13.139 1.000 2. 1,2 , Dimethylbenzene 14.702 0.172 14.753 0.361 3. 5- (p-methylvinyl) -1,3 — —— 15.020 0.299 cyclopentadiene 4-benzaldehyde 17.631 0.859 17.663 0.812 5. Propyl benzene — —— 18.018 0.100 6 . 1, ethyl-2, methylbenzene 18.228 0.311 18.260 0.374 7. 1,3,5 trimethylbenzene 18.507 0.156 18.532 0.179 8.1, methyl ethylbenzene 18.915 0.115 18.942 0.114 9. 1,2,4 Trimethylbenzene 19.455 0.898 19.479 0.734 10. Bicyclo [2,2,1] heptyl-2,5 20.222 0.627 20.237 0.222 Diene-7 alcohol 11.1, methyl-5- (1-methylethyl) 20.316 0.655 20.332 0.363 Cyclone has entertainment "12.1,2,3-trimethylbenzene 20.496 0.138 — —— 13.4, methylphenol 20.928 0.152 — —— 14. unknown 25.217 0.224 —— 15.4,5 dimethyl-1-hexene 26.052 0.188 — —— 16.4,5 dimethyl-1-hexene 26.334 0.438 — —— 17.4,5 dimethyl-1-hexene 26.906 1.000 — —— 18. Unknown 27.465 0.168 — —— 19. Unknown 30.807 0.232 — 20.3 Methyltridecane 31.014 0.361 — —— 21.3 Methyltridecane 33.426 0.221 — —— 22.3 Methyltridecane 34.107 0.512 — — 23 .Unknown 34.217 0.303 — —— 24.4,5 dimethyl-1-hexyl 35.119 0.574 — —— 25. Unknown 36.071 0.872 — — 26. Unknown 36.246 0.172 — —— * RT: stands for dead time; RA: Represents the area ratio of the accumulated precursors obtained by the chromatography mass spectrometer. (Please read the precautions on the back before writing this page) The paper size is in accordance with Chinese National Standard (CNS) A 4 specifications (210 X 297 mm) H 40 000 i2i46 AB Amendment v Year Month Date / 84. 4. 1 7 Supplement A6 V. Description of the invention (up) Example 2: Controlling the thickness and content of the Pd eggshell by the impregnation time Step 1: Respectively using the same 10g diameter Al4〇3 spherical support, impregnated in 200 mL supersaturated The Pd (CH3C00) 2 toluene solution was shaken with a 100 rpm shaker to control different impregnation times of 0.5 hours, 1 hour, 3 hours, 6 hours, 12 hours and 24 hours. Then filter it to 100. (: Drying for 1 hour, rising from normal temperature to 35 (TC, maintaining for 6 hours at a temperature of lire / min. Step 2: Measure the Pd metal distribution by EPM analysis of the catalyst samples impregnated at different times, and the analysis results are shown in Figure Ί Graph the thickness of the Pd eggshell in Figure H with r / R versus time as shown in Figure 12; the longer the impregnation time, the thicker the thickness of the Pd eggshell. Pd weight percentage vs. impregnation time is shown in Figure 13; impregnation The longer the time, the more the Pd weight percentage content is.Example 3: Controlling the Pd dispersion of the Pd eggshell catalyst at the flaw temperature Step 1: Use 0.534g Pd (CH3C00) 2 with a purity of 47 wt% Pd, Dissolved in 750mL toluene, weighed I25.24g of β-ΑΙ2〇3 (its spherical particle diameter is 2 delete, its surface area is 82.4 n ^ / g, pore volume is 570 cc / g) β will Al2〇3 Put it in the solution, mix with a 100 rpm shaker for 3 hours, filter and dry with KXTC for 1 hr. Step 2: Divide the dried catalyst sample into five equal weight samples, each catalyst sample is divided into 1 (TC / Min Heating rate increased from normal temperature to 300 ° C, 400 ° C, 500. (:, 600 ° C and 700 ° C, and then maintained at the final temperature Hold for 6 hours. The catalyst sample is analyzed by elemental analysis to obtain 0.2 wt% Pd, and the Pd measured by EPMA analysis is distributed in the outer layer of the support. Its pd eggshell thickness is about r / Rr. The difference is different. The content of Pd is measured quantitatively at 50 ° C with a TC burned catalyst sample at 21 points of EPMA, which is shown in Figure 14. ΦIit thing ¾ More item 'write this page) I install. Step 3: The obtained catalyst samples of different burnt temperatures were weighed respectively with 〇300 g samples, and the temperature was increased from 25 to 10 ° C / min. Increase the temperature from 300 ° C to 300 ° C. Use Ar / H2 = 9/1 molar ratio of 30cc per minute to pass through the sample for Temperature Programmed Reduction (TPR). When the temperature reaches 300 ° C, heat the furnace Open, rapid cooling process temperature adsorption experiment (Temperature Resolved Sorption, table paper scale is applicable to China National Standards (CNS) A 4 specifications (210 X 297 mm> 272146 Amendment 84.4. "Affirmation Year A6 B6 Central Ministry of Economic Affairs Printed by the Bureau of Standards and Technology β-Consumer Cooperatives V. Description of Invention (8) Referred to as TRS). According to J. of C atal. vol. 96, 1985, P 51 literature data, measured the amount of hydrogen on the chemisorption hydrogen of the higher adsorption temperature and bulk palladium of the low temperature absorption (Absorption) in the TRS experiment, calculated according to the following equation Free of metal dispersion.

DrAc / (Ac + 2.8 Aa) The equation shows D = Dispersion

Ac = H2 Chemisorption peak area Aa 2 H2 Absorption (bulk) peak area The TPR and TRS experimental spectrum results of various catalyst samples are shown in Figure 15. The TRS spectra of various samples in Figure 15 are used to calculate the Pd metal dispersion. The calculation result is plotted against the temperature change of the flaw in Figure 16. It is clear from the results in Figure 16 that the Pd metal dispersion becomes worse as the burning temperature increases. Example 4: Preparation of Pd metal distribution linearly descends from the outer layer to the inside of the spherical center

Step 1: Use Ni (N〇3) 2.6H2〇 to dissolve in deionized water, make a concentration of 1.0M, and set the spherical diameter to 4mm r-Al2〇3 (the SA = 173m2 / g, PV · 2 0.760 cc / g ) Put it in the solution and treat it with wet impregnation for 1 hour. Then filter and dry at ho ° C for 1 hour. ^ Step 2: Put the above-obtained catalyst sample into supersaturated pd (CH3C⑻) 2 and dissolve it in toluene, then use wet impregnation method for 0.5 hours, and then filter at 110 °. 〇Dry hour. Step 3: The catalyst samples obtained above were analyzed by EPMA to measure the distribution of Ni and Pd metals, as shown in Figure 17. From the results in Figure 17, it is obvious that the distribution of pd metal is linearly decreasing from the outer layer to the inside of the sphere center, while the distribution of Ni metal is uniform. Embodiment 5: Preparation of a catalyst for controlling the thickness of Ni eggshells by impregnation time Step 1: Dissolve Ni (N03) 2.6H2〇 in THF solvent and prepare a concentration of 3.0M. Respectively with the same lg diameter of 2mm rA 丨 2〇3 (the 5 A = 173 m2 / g, ρ, ν tsmtm (21〇χ 297) ------ -------- I- ----- -------- ¾ ------. 玎 ---- .Line (please read the back first; i will write this page if you want to)

272146 V. Description of the invention (9) 0.760 cc / g) spherical support, impregnated with 5 cc of the above Ni metal solution. Control the different impregnation time 5 minutes, 10 minutes, 20 minutes, 40 minutes, and then filter in 丨 20. (: Drying for 12 hours. Step ^ The catalyst sample obtained above, as shown in the analysis of the test chamber metal sub-graph 10 #__, the longer the impregnation time is, please (read the notes on the back first and then write this page)丨 Installed. Green-Printed by the WC Industrial and Consumer Cooperative of the Central Standards Bureau of the Ministry of Hydrocarbon Economy-This paper M applies the Chinese national standard (CNS_i A 4 specifications (210 X 297 male cage) _ 272146 Amendment 84. 4. 1 7 Supplement A6 B6 5 Description of invention (1〇) Patent search: 1. E. Michalco, US Patents 3,259,454 and 3,259,589 (July 5, 1966) 2. John W. Geus et al ”US4,113,658. (Sep · 12, 1978). 3. Louis Hegedus etal., US Patent 4, 128, 506 (Dec. 5, 1978) 4. Yukimitsu Mita etal., US Patent 4,376,724 (Mar. 15, 1983). 5. Gail M. Qualeatti etaL, US Patent 4,519,951 (May 28 , 1985) Please read the notices first and then write this page. The printed version of the Ministry of Economic Affairs, Central Standards Bureau, Beigong Consumer Co., Ltd. The paper size is in accordance with the Chinese National Standard (CNS) A 4 specifications (210 X 297 mm). Ί, 40 000 272146 Amend I84. Δ. 3〇 Supplement Α6 Β6 V. Invention description (丨 l) In the Ministry of Economy Standards Bureau Beigong Consumer Cooperation Du Yin ¾ Brief description of the picture Figure 1: Palladium metal distribution results of uniform catalyst electron microprobe (ΕΡΜΑ). (X axis represents the thickness of palladium metal eggshell, r / R; Y axis represents the metal Content, wt%). Figure 2: Distribution results of palladium metal in eggshell catalyst electron microprobe (ΕΡΜΑ). (X axis represents palladium metal eggshell thickness, r / R; Y axis represents palladium metal content, wt%) Figure 3: The composition of the reaction mixture plotted against the reaction time (a) eggshell catalyst (b) homogeneous catalyst, reaction temperature = 44 ° C, pressure 2 30 atm, weight liquid space velocity = i8h-1, hydrogen / Isoprene molar ratio = 2.262 (□: isoprene, 〇. Isoprene '' △ · · isoprene). (X axis represents the reaction time, hours; γ axis represents the molar concentration, Mo Ear / L) The isoprene concentration of the two catalysts is plotted against the reaction time. Reaction temperature = 4fC, pressure 2 30 atm, weight space liquid flow rate 2 i8h-l, hydrogen / isoprene mole ratio = 2.262 (〇: eggshell catalyst, △: homogeneous catalyst). (X axis represents reaction time, hours; γ axis represents isoprene concentration, moles / liter). The carbon precursors of the two kinds of waste catalysts are traced by a micro-scanning calorimeter (11 catalysts: uniform catalysts). (The X axis represents the reaction temperature, and the C and Y axes represent the heat flux, in arbitrary units). The chromatographic mass spectrometer (GC / mass) spectra of the two waste catalyst carbon deposit precursors (a) are both SS () b). Egg-like catalyst. (The x-axis represents the stagnation time '*; the γ-axis represents the letter Figure 7 .: The reaction time of the main products of the two catalysts, isoprene, is plotted. The reaction temperature is 44 C, the pressure is 30 atm, and the weight liquid space velocity is two- i. Hydrogen / isohydrogen f Mohr ratio 2.262 (〇: eggshell catalyst, △: uniform touch ° (X-axis represents reaction time, hours; γ-axis represents isoshuren concentration, mol / liter) Figure 4 Figure 5 (Please read the precautions on the back before writing this page). Installed. -Line- ^, shaped thin middle group (CNS) A 4 specifications (21Q χ 297 ^ 272146 years 84. 5. 30 ^ Amendment · A Fan A6 B6 Printed by the 8th Consumer Cooperative of the Central Standardization Bureau of the Ministry of Hydrocarbon Economy " V. Description of the invention (12) Figure 8: Undesirable product isopentane of two catalysts plotted against reaction time. Reaction temperature = 44 ° C, pressure = 30 atm, weight liquid space velocity = i8h-1, hydrogen / isoprene molar ratio = 2.262 (〇: eggshell catalyst, △ uniform catalyst). (X axis represents Reaction time, hours; Y-axis represents isopentylate concentration, mole / liter). Figure 9: Isoprene selectivity of two catalysts plotted against reaction time Reaction temperature II 44. (:, pressure = 30 atm, weight liquid space velocity = i8h-1, hydrogen / isoprene molar ratio = 2.262 (〇: eggshell catalyst, △ uniform catalyst). The X axis represents the reaction time in hours; the γ axis represents the selectivity of isoprene. Figure 10: The selectivity of 2 methyl 1 butene and 2 methyl 2 butene for the two catalysts plotted against the reaction time. Reaction temperature = 44 ° C, pressure = 30 atm, weight liquid space velocity = 18h_l, hydrogen / isoprene molar ratio = 2.262 (〇: eggshell catalyst 2 methyl 2 butene: eggshell catalyst 2 Methyl 1 butene, △: Homo catalyst 2 methyl 2 butene, ▲: Homogeneous catalyst 2 methyl 1 butene). (Χ axis represents reaction time, hour; Υ axis represents selectivity,% Figure 11: Palladium metal distribution results obtained by impregnating catalyst electroprobe (EPMA) at different times. (1): 0.5 hours, (2): 1 hour, (3): 3 hours, (4): 6 hours, (5): 12 hours, (6): 24 hours. (The X axis table shows the position of the second support body, r / R; Y pumping means no metal content, any sound unit). Figure 12 ^ Thickness of palladium metal eggshell Variation of immersion time. () (Axis represents time, Y axis represents palladium metal eggshell thickness, r / R) ◦ ° Temperature, small figure 13: Palladium metal weight percentage vs. impregnation time. (Χ axis represents impregnation hour ; The Υ axis represents the content of the new metal, wt%)., Time, (please read the precautions on the back and write this page again). · 11_ (Applicable to China National Standard 297 public cage)

Year Factory i Q

V. Description of the invention (13) Figure 14: 0.2wt% palladium / alumina catalyst at 50 (TC 煆 燆 its electron microprobe (ΕΡΜΑ) spectrum. (X axis represents the thickness of palladium metal eggshell, r / R; Y The axis represents the palladium metal content, wt%). Figure 15: 0.2wt% palladium / alumina catalyst at different burning temperature range temperature reduction (tpr) spectrum. (A) 300 (b) 400 ° C (c) 500 ° C (d) 60 (rC (e) 70 (rC. (X pumping represents reaction time, minutes; Y axis represents hydrogen consumption, arbitrary units).

Figure 16: 0.2wt% palladium / alumina catalyst scorching temperature vs. palladium metal dispersion. (X axis represents the burning temperature, ° C; Y axis represents the degree of dispersion). Figure 17: Electron microprobe (EPMA) pattern of palladium and nickel metal distribution. (The X axis represents the thickness of the metal eggshell, r / R; the Y axis represents the palladium metal content, wt% / nickel metal content, wt%). Figure 18: Electron microprobe (EPMA) map of nickel metal distribution. (A): 5 points, (b): 10 points, (c): 20 points, (d): 40 points. (The X axis represents the thickness of the nickel metal eggshell, r / R; the Y axis represents the nickel metal content, in arbitrary units). ------------------: --------------, 11I (Please read the notes on the back before writing this page) Economy The paper printed by the Ministry of Standards and Staff ’s Consumer Cooperative applies the Chinese National Standard (CNS) Grade 4 (210 X 297 g) d〇non

Claims (1)

272146 A7 Β7 C7 D7 Employee Consumer Cooperative of Central Standard, Ministry of Economic Affairs Printed 5 * t, patent application scope The patent application scope of the present invention is as follows: 1. A method for preparing eggshell metal catalyst for selective reduction or oxidation reaction, Its characteristics are: this method uses organic or inorganic metal compounds (metals include Pd, Ni, Co, Mo, Cu, Pt, Fe, Ag, Ir, Pb, Re, Ti, Sn, V Zn, etc.), at room temperature Or dissolve in organic solvent under heating (organic solvents can use aromatics such as toluene, benzene, xylene, alcohols such as methanol, THF, etc.), or dissolve in a variety of mixed organic solvents, using wet impregnation method or spray Method to attach the active metal in the prepared organic or inorganic metal concentration solution to the carrier (wherein the carrier contains AI2O3, Si〇2, Zeolite, Ti〇2, Zr〇2, MgO, activated carbon, polymer Si 'or above Carrier)) 'control of its impregnation time or the concentration of the impregnated metal solution can accurately control the thickness and content of the metal eggshell, and the obtained single or multiple eggshell-like metal contacts Various eggshell of metal catalyst obtained above, may further utilize different calcination temperature, to control its degree of dispersion of the metal. 2. According to the method described in the first item of the patent application, an eggshell palladium catalyst used for selective reduction or oxidation reaction is characterized by using Pd (CH3COO) 2 supersaturated or dissolved in an organic solvent at an appropriate concentration In toluene, the wet organic impregnation method is used to prepare the prepared organic solvent toluene, and the wet organic impregnation method is used to attach the palladium metal in the prepared organic metal solution to the alumina (AI2O3) carrier to control its different impregnation time (〇 ~ 48 hours), to control the eggshell thickness of palladium metal on the alumina support (from 0 mm to the radius of the whole support) and the weight percentage of palladium metal (from 〇 ~ 4.0 wt%). 3. According to the method described in the first item of the patent application, a method for preparing a catalyst for the selective reduction or oxidation reaction to linearly distribute the metal from the outer layer to the inside of the center of the support is characterized by using Ni (N 〇3) 2 · 6H2〇 aqueous solution, using wet impregnation method to make nickel metal adhere to the alumina support, and then use the method as described in the second item of the scope of the patent application, impregnated with organic saturated metal solution, so that the distribution of palladium metal In order to fall linearly from the outside to the inside of the center of the support, the nickel metal is a bimetallic catalyst that is evenly distributed. (Please read the precautions on the back before writing this page), installed-'Tr line. This paper is again applicable to the Chinese National Standard (CNS) A 4 specifications (210 X 297) Milk i46 A7 B7 C7 D7, apply for a patent Fan Yuan 4.1 requested the method described in the second and third paragraphs of the patent Gu, and prepared the cans that were in the shape of eggs or were read from the external towels, and then burned at a temperature of ⑽ ~ 1200. 〇Control the dispersion of palladium metal. Dish 5. As in the methods described in the first, second, and third items of the patent application, the prepared catalyst with uneven metal separation is used in the selective hydrogenation or selective oxidation reaction (such as reaction A- B-C), as a result, a better selectivity and shame rate of the intermediate product (β) can be obtained. (Please read the precautions on the back before filling in this page). Packing. • Tr ‘Line-Printed by the Ministry of Economic Affairs Central Standard 户 R 工 consumer cooperative«