Anthraquinone hydrogenation catalyst and preparation method thereof
阅读说明：本技术 一种蒽醌加氢催化剂及其制备方法 (Anthraquinone hydrogenation catalyst and preparation method thereof ) 是由 张晓昕 王宣 宗保宁 于 2019-08-30 设计创作，主要内容包括：一种蒽醌加氢催化剂,其特征在于,以经磷修饰的活性氧化铝为载体,以钯为主活性组分,以选自银、铜、钴、镧、铈、锰、铁和镍中的一种或几种为助活性组分；在所述的经磷修饰的活性氧化铝载体中,所述的磷的质量含量为0.1～30％；所述的主活性组分在催化剂中的质量含量为0.01～10％；所述的助活性组分在催化剂中的质量含量为0～8％。该催化剂在浆态床反应器中进行蒽醌加氢反应,耐磨性能更好,适应蒽醌加氢工作液存在水的环境,催化剂的活性和选择性有显著改善。(An anthraquinone hydrogenation catalyst is characterized in that active alumina modified by phosphorus is used as a carrier, palladium is used as a main active component, and one or more of silver, copper, cobalt, lanthanum, cerium, manganese, iron and nickel are used as auxiliary active components; in the phosphorus-modified activated alumina carrier, the mass content of phosphorus is 0.1-30%; the mass content of the main active component in the catalyst is 0.01-10%; the mass content of the auxiliary active component in the catalyst is 0-8%. The catalyst is used for anthraquinone hydrogenation reaction in a slurry bed reactor, has better wear resistance, is suitable for the environment of water in the anthraquinone hydrogenation working solution, and has obviously improved activity and selectivity.)
1. An anthraquinone hydrogenation catalyst is characterized in that active alumina modified by phosphorus is used as a carrier, and palladium is used as a main active component.
2. The hydrogenation catalyst for anthraquinone according to claim 1, wherein the phosphorus-modified activated alumina carrier contains 0.1 to 30% by mass of phosphorus, preferably 0.5 to 20% by mass of phosphorus.
3. An anthraquinone hydrogenation catalyst according to claim 1, wherein the mass content of the main active component in the catalyst is 0.01 to 10%, preferably 0.05 to 8%, more preferably 0.1 to 4%.
4. The anthraquinone hydrogenation catalyst according to claim 1, wherein one or more selected from silver, copper, cobalt, lanthanum, cerium, manganese, iron and nickel are used as an auxiliary active component, and the mass content of the auxiliary active component in the catalyst is 0-8%, preferably 0.05-8%, and more preferably 0.1-6%.
5. The anthraquinone hydrogenation catalyst according to claim 1, wherein the phosphorus content in the phosphorus-modified activated alumina carrier is 2-10% by mass; the mass content of the main active component in the catalyst is 1-2%; the mass content of the auxiliary active component in the catalyst is 1-5%, and the auxiliary active component is selected from one or more of silver, copper, lanthanum and cobalt.
6. An anthraquinone hydrogenation catalyst according to claim 4 or 5, wherein the co-active component is silver and/or copper.
7. A process for the preparation of an anthraquinone hydrogenation catalyst according to one of the claims 1 to 6, characterized by comprising the steps of:
a. drying the active alumina powder, and measuring the saturated water absorption capacity;
b. according to P2O5/Al2O3The mass ratio of the P to the activated alumina is 0.001-0.3 to calculate the amount of P required for 100g of activated alumina2O5The mass number of the phosphorus-containing compound is calculated, and the mass of the corresponding required phosphorus-containing compound is calculated;
c. weighing the required amount of deionized water and the amount of the phosphorus-containing compound to prepare a corresponding solution of the phosphorus-containing compound, and fully mixing, drying and roasting the solution of the phosphorus-containing compound and activated alumina to obtain a carrier;
d. c, dipping the carrier obtained in the step c by using a solution of a compound containing a main active component and an optional compound containing an auxiliary active component in required amount, and dropwise adding a NaOH solution to obtain a catalyst precursor suspension;
e. introducing hydrogen into the catalyst precursor suspension at the temperature of 5-30 ℃, and reducing and activating the catalyst precursor obtained in the step d under stirring;
f. washing the catalyst precursor obtained in the filtering step e with deionized water to Cl-The concentration is less than 10-6M, then at 70-80 ℃ and a vacuum degree of 1.013X 10-3～1.013×10-4And drying for 0.5-12 h under the condition of Pa to obtain the anthraquinone hydrogenation catalyst.
8. The method according to claim 7, wherein the activated alumina powder in step a is pseudo-boehmite powder or gamma-Al2O3And (3) powder.
9. The method according to claim 7, wherein the phosphorus-containing compound in step c is selected from phosphoric acid, ammonium dihydrogen phosphate, magnesium dihydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, and metal phosphide.
10. The preparation method according to claim 7, wherein the compound containing the main active component in the step d is palladium chloride, palladium nitrate, palladium acetate, chloropalladic acid or ammonium chloropalladate; the compound of the auxiliary active component is nitrate, hydrochloride or carbonate of the auxiliary active component.
Technical Field
The invention relates to a hydrogenation catalyst and a preparation method thereof, in particular to an anthraquinone hydrogenation catalyst taking palladium as an active component and a preparation method thereof.
Background
H2O2The O atom in (A) adopts an inequality sp2Hybrid, with an oxidation number of-1, and thus one of its characteristic chemical properties is oxidative. Due to H2O2The final product as the oxidant is water, which does not cause secondary pollution to the environment, so the oxidant is an ideal green oxidant and is widely used in almost all industrial fields, particularly chemical industry, environmental protection and the like. Emerging green chemical processes such as cyclohexanone ammoximation to prepare hexaneThe epoxidation of lactam and propylene to prepare propylene oxide and the like, and further develops H2O2The use of (1).
Although various methods such as an isopropyl alcohol autoxidation method, an oxygen cathode reduction method, a hydrogen-oxygen direct synthesis method, an anthraquinone method, etc. can be used to produce H2O2However, more than 98% of products are produced globally by the anthraquinone process. The anthraquinone process is currently the most widely used process for producing H at home and abroad2O2The method of (1). The principle of anthraquinone method is that alkyl anthraquinone is hydrogenated under the action of hydrogen and catalyst to produce alkyl anthrahydroquinone, which is then restored to alkyl anthraquinone under the action of oxygen oxidation to produce H2O2. Wherein the hydrogenation process of the alkyl anthraquinone is the anthraquinone method for producing H2O2The core of the process.
Anthraquinone process for producing H2O2In the process, hydrogenation of anthraquinone is the most critical, and the hydrogenation catalyst is the core of the reaction, which largely determines the production capacity and cost of the device. In the production process, the catalyst with high activity can be directly produced to obtain H with higher concentration2O2Thereby reducing the investment in the product concentration process; the high selectivity catalyst can reduce the occurrence of side reactions in the hydrogenation process, which not only consume expensive anthraquinone, but also easily deactivate the catalyst.
The anthraquinone process can be used to produce H, depending on the reactor configuration in the hydrogenation process2O2The method comprises two major types, namely a fixed bed anthraquinone hydrogenation process and a slurry bed anthraquinone hydrogenation process.
The fixed bed anthraquinone hydrogenation process has the defects of large bed temperature rise, easy bias flow, local hot spots and the like, is easy to cause excessive hydrogenation of anthraquinone, increase of degradation species and quantity, reduces the stability of the catalyst, limits the hydrogen efficiency of a hydrogenation unit, and is difficult to enlarge a production device. At present, the domestic fixed bed process generally controls the hydrogen efficiency to be 6-7 g/L, and the scale of the device is about 5 million tons/year at most.
Compared with a fixed bed, the slurry bed anthraquinone hydrogenation process has excellent mass transfer and heat transfer properties, uniform reaction temperature and can effectively control the generation of degradation products. In recent years, the slurry bed anthraquinone hydrogenation process has become a hot spot of research and development of various large companies.
In the slurry bed anthraquinone hydrogenation process, the collision and friction of the catalyst in the reactor are severe, if the wear resistance of the catalyst is insufficient, catalyst powder is easily generated, the powder affects the treatment capacity of the filtering device on one hand, and the powder can enter the oxidation equipment along with the hydrogenated liquid on the other hand, so that the hydrogen peroxide is decomposed in the oxidation equipment, the yield is reduced, and even explosion accidents can be caused.
For the palladium catalyst supported on a carrier, it is recommended to use catalysts supported on various carriers such as silica, alumina, silica-alumina, aluminosilicate, carbonates of alkaline earth metals and activated carbon, but all of the catalysts do not meet the requirements required for industrial catalysts such as low cost, high catalytic strength, high catalytic activity and high selectivity.
The palladium catalyst supported on alumina is one of several industrially applicable catalysts which have relatively high activity and are easily regenerated by calcination, but also have disadvantages in that a large amount of by-products are produced in the hydrogenation reaction of anthraquinones and other disadvantages such as severe deterioration of the activity due to the presence of water in the working liquid.
CN104549246A discloses a palladium-based catalyst, which uses a composite oxide modified by lithium and composed of zirconium dioxide and activated alumina as a carrier, uses palladium as a main active component, and uses one or more selected from magnesium, calcium, lanthanum, cerium, iron, cobalt, nickel and zinc as an auxiliary active component. The catalyst has greatly reduced activity in a working fluid in the presence of water.
CN104549236A discloses a hydrogenation catalyst, which uses a boron-modified composite oxide composed of silica and activated alumina as a carrier, uses palladium as a main active component, and uses one or more selected from magnesium, calcium, lanthanum, cerium, manganese, iron, cobalt or nickel as an auxiliary active component. The catalyst also has the problem of instability in aqueous working fluids.
US5772977 discloses a process for producing hydrogen peroxide by the anthraquinone process. The process uses a supported palladium catalyst, and the supported amount of palladium is 0.2-10 wt% the carrier is alumina, silica, titania or mixtures thereof. The carrier has a pore diameter of 5 to 100nm, a particle diameter of 1 to 200 μm, and a specific surface area of 20 to 200m2The supported palladium catalyst has good wear resistance, but the carrier acidity is large, so that the supported palladium catalyst is not beneficial to desorption of reaction products, is easy to generate a transitional hydrogenation byproduct and increases consumption of anthraquinone.
The above-mentioned prior art catalyst can improve the selectivity of the hydrogenation reaction of anthraquinones to some extent, but the activity of the catalyst is inevitably weakened due to the presence of water in the working solution.
Disclosure of Invention
One of the purposes of the invention is to provide an anthraquinone hydrogenation catalyst which is suitable for the environment of water existing in an anthraquinone hydrogenation working solution.
The invention also aims to provide a preparation method of the anthraquinone hydrogenation catalyst.
In order to realize one of the purposes of the invention, the anthraquinone hydrogenation catalyst is characterized in that active alumina modified by phosphorus is used as a carrier, palladium is used as a main active component, and one or more of silver, copper, cobalt, lanthanum, cerium, manganese, iron and nickel are used as auxiliary active components; in the phosphorus-modified activated alumina carrier, the mass content of phosphorus is 0.1-30%; the mass content of the main active component in the catalyst is 0.01-10%; the mass content of the auxiliary active component in the catalyst is 0-8%.
In order to achieve the second object of the present invention, the present invention provides a method for preparing an anthraquinone hydrogenation catalyst, comprising the steps of:
a. drying the active alumina powder, and measuring the saturated water absorption capacity;
b. according to P2O5/Al2O3The mass ratio of the P to the activated alumina is 0.001-0.3 to calculate the amount of P required for 100g of activated alumina2O5The mass number of the phosphorus-containing compound is calculated, and the mass of the corresponding required phosphorus-containing compound is calculated;
c. weighing the required amount of deionized water and the amount of the phosphorus-containing compound to prepare a corresponding solution of the phosphorus-containing compound, and fully mixing, drying and roasting the solution of the phosphorus-containing compound and activated alumina to obtain a carrier;
d. c, dipping the carrier obtained in the step c by using a solution of a compound containing a main active component and an optional compound containing an auxiliary active component in required amount, and dropwise adding a NaOH solution to obtain a catalyst precursor suspension;
e. introducing hydrogen into the catalyst precursor suspension at the temperature of 5-30 ℃, and reducing and activating the catalyst precursor obtained in the step d under stirring;
f. washing the catalyst precursor obtained in the filtering step e with deionized water to Cl-The concentration is less than 10-6M, then at 70-80 ℃ and a vacuum degree of 1.013X 10-3～1.013×10-4And drying for 0.5-12 h under the condition of Pa to obtain the anthraquinone hydrogenation catalyst.
The anthraquinone hydrogenation catalyst provided by the invention has better wear resistance, is suitable for the environment of water existing in the anthraquinone hydrogenation working solution, and has obviously improved activity and selectivity.
Detailed Description
The anthraquinone hydrogenation catalyst provided by the invention is characterized in that active alumina modified by phosphorus is used as a carrier, palladium is used as a main active component, and one or more of silver, copper, cobalt, lanthanum, cerium, manganese, iron and nickel are used as auxiliary active components; in the phosphorus-modified activated alumina carrier, the mass content of phosphorus is 0.1-30%; the mass content of the main active component in the catalyst is 0.01-10%; the mass content of the auxiliary active component in the catalyst is 0-8%.
In the present invention, the activated alumina is well known to those skilled in the art as a carrier, and its precursor is, for example, pseudoboehmite or γ -Al2O3. The preferable particle size distribution of the alumina carrier is 1-400 mu m, wherein 90 wt% of the carrier particle size distribution is 40-200 mu m, the average particle size is 80-90 mu m, the pore volume is 0.2-2.0 mL/g, and the specific surface area is 80-300 m2(ii) in terms of/g. In the active alumina modified by phosphorus as a carrier, the phosphorus is preferably 0.5-20% by mass; the main active componentThe mass content of palladium in the catalyst is preferably 0.05-8%, more preferably 0.1-4%; the mass content of the auxiliary active component in the catalyst is preferably 0.05-8%, and more preferably 0.1-6%.
In a preferred embodiment of the present invention, the phosphorus-modified activated alumina is a carrier, wherein the phosphorus content is 2 to 10% by mass; the mass content of the main active component in the catalyst is 1-2%; the mass content of the auxiliary active component in the catalyst is 1-5%, the auxiliary active component is preferably one or more of silver, copper, lanthanum and cobalt, and more preferably the auxiliary active component is preferably silver and/or copper.
The preparation method of the anthraquinone hydrogenation catalyst is characterized by comprising the following steps:
a. drying the active alumina powder, and measuring the saturated water absorption capacity;
b. according to P2O5/Al2O3The mass ratio of the P to the activated alumina is 0.001-0.3 to calculate the amount of P required for 100g of activated alumina2O5The mass number of the phosphorus-containing compound is calculated, and the mass of the corresponding required phosphorus-containing compound is calculated;
c. weighing the required amount of deionized water and the amount of the phosphorus-containing compound to prepare a corresponding solution of the phosphorus-containing compound, and fully mixing, drying and roasting the solution of the phosphorus-containing compound and activated alumina to obtain a carrier;
d. c, dipping the carrier obtained in the step c by using a solution of a compound containing a main active component and an optional compound containing an auxiliary active component in required amount, and dropwise adding a NaOH solution to obtain a catalyst precursor suspension;
e. introducing hydrogen into the catalyst precursor suspension at the temperature of 5-30 ℃, and reducing and activating the catalyst precursor obtained in the step d under stirring;
f. washing the catalyst precursor obtained in the filtering step e with deionized water to Cl-The concentration is less than 10-6M, then at 70-80 ℃ and a vacuum degree of 1.013X 10-3～1.013×10-4And drying for 0.5-12 h under the condition of Pa to obtain the anthraquinone hydrogenation catalyst.
In the preparation method of the invention, the activated alumina powder in the step a is preferably pseudo-boehmite powder or gamma-Al2O3And (3) powder. The phosphorus-containing compound in step c is preferably phosphoric acid, monoammonium phosphate, magnesium dihydrogen phosphate, potassium dihydrogen phosphate or sodium dihydrogen phosphate, and more preferably phosphoric acid, monoammonium phosphate or sodium dihydrogen phosphate. The compound containing the cinnabar active component in the step d is preferably palladium chloride, palladium nitrate, palladium acetate, chloropalladate or ammonium chloropalladate. The compound of the co-active component is preferably a nitrate, hydrochloride or carbonate of this co-active component, for example silver nitrate, copper nitrate, cobalt nitrate, lanthanum nitrate and the like.
In the method of the invention, the drying is carried out in an oven at 120 ℃, the roasting is carried out for 0.5-12 h at 300-750 ℃, the dipping is carried out for 1-720 min at 20-100 ℃, and the constant temperature is preferably 2-10h after the NaOH solution is dripped. And f, storing the obtained anthraquinone hydrogenation catalyst under the protection of nitrogen.
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
Examples 1-8 illustrate the anthraquinone hydrogenation catalyst and method of preparation provided by the present invention.
Example 1
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.25g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
100mL of an aqueous solution having a palladium chloride concentration of 15g/L was weighed, 75g of the carrier obtained in step (1) was taken, and the carrier was dispersedImmersing in Pd chloride solution at room temp for 12 hr, dropping 12.5mL of 5 wt% NaOH solution, and holding the temp for 2-10 hr to obtain suspension. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3－1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S1.
The mass composition of each component in the catalyst S1 is shown in Table 1.
Example 2
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O38.2g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.05 and added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, the ammonium phosphate solution and the activated alumina are mixed and stirred uniformly, and then the mixture is moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
100mL of an aqueous solution having a palladium chloride concentration of 15g/L was measured, 75g of the carrier obtained in step (1) was taken, the carrier was dispersed in the palladium chloride solution, immersed at room temperature for 12 hours, and 12.5mL of a 5 wt% NaOH solution was added dropwise thereto and the temperature was maintained for 2 to 10 hours. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S2.
The mass composition of each component in the catalyst S2 is shown in Table 1.
Example 3
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O313g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.08 and added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, the ammonium dihydrogen phosphate solution and the activated alumina are mixed and stirred uniformly, and then the mixture is moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
100mL of an aqueous solution having a palladium chloride concentration of 15g/L was measured, 75g of the carrier obtained in step (1) was taken, the carrier was dispersed in the palladium chloride solution, immersed at room temperature for 12 hours, and 12.5mL of a 5 wt% NaOH solution was added dropwise thereto and the temperature was maintained for 2 to 10 hours. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S3.
The mass composition of each component in the catalyst S3 is shown in Table 1.
Comparative example 1
The difference from example 1 is that2O3No phosphorus modification. This gave comparative catalyst D1. The mass composition of the components of comparative catalyst D1 is shown in Table 1.
Example 4
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.25g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
80mL of chloridization solution with the concentration of 15g/L and 3.75g/L are weighedAnd (2) taking 75g of the carrier obtained in the step (1), dispersing the carrier into a palladium chloride solution, soaking at room temperature for 12 hours, dropwise adding 12.5mL of 5 wt% NaOH solution, and keeping the temperature for 2-10 hours. Then, hydrogen gas was introduced into the suspension at 30 ℃ and the suspension was reductively activated for 4 hours under stirring at a flow rate of 30 ml/min. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S4.
The mass composition of each component in the catalyst S4 is shown in Table 1.
Comparative example 2
The difference from example 4 is that2O3No phosphorus modification. This gave comparative catalyst D2. The mass composition of the components of comparative catalyst D2 is shown in Table 1.
Example 5
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.25g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
80mL of aqueous solutions of palladium chloride and copper nitrate with concentrations of 15g/L and 3.75g/L respectively are measured, 75g of the carrier obtained in the step (1) is taken, the carrier is dispersed into the palladium chloride solution, the carrier is immersed for 12 hours at room temperature, 12.5mL of NaOH solution with concentration of 5 percent by weight is dripped, and the constant temperature is kept for 2 to 10 hours. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under Pa, and storing under nitrogen protection to obtain catalystAgent S5.
The mass composition of each component in the catalyst S5 is shown in Table 1.
Comparative example 3
The difference from example 5 is that2O3No phosphorus modification. This gave comparative catalyst D3. The mass composition of the components of comparative catalyst D3 is shown in Table 1.
Example 6
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.25g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
80mL of palladium chloride and cobalt nitrate aqueous solutions with the concentrations of 15g/L and 3.75g/L are measured, 75g of the carrier obtained in the step (1) is taken, the carrier is dispersed into the palladium chloride solution and is immersed for 12 hours at room temperature, 12.5mL of NaOH solution with the concentration of 5 percent (weight) is dripped, and the constant temperature is kept for 2 to 10 hours. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S6.
The mass composition of each component in the catalyst S6 is shown in Table 1.
Comparative example 4
The same as example 6 except that gamma-Al2O3No phosphorus modification. This gave comparative catalyst D4. The mass composition of the components of comparative catalyst D4 is shown in Table 1.
Example 7
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.25g of ammonium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding ammonium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
80mL of aqueous solutions of palladium chloride and lanthanum nitrate with the concentrations of 15g/L and 3.75g/L are measured, 75g of the carrier obtained in the step (1) is taken, the carrier is dispersed into the palladium chloride solution, the carrier is immersed for 12 hours at room temperature, 12.5mL of NaOH solution with the concentration of 5 percent by weight is dripped, and the constant temperature is kept for 2 to 10 hours. Hydrogen was passed through the suspension at 30 ℃ and at a flow rate of 30ml/min, and reduction activation was carried out for 4 hours with stirring. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S7.
The mass composition of each component in the catalyst S7 is shown in Table 1.
Comparative example 5
The same as example 7 except that gamma-Al2O3No phosphorus modification. This gave comparative catalyst D5. The mass composition of the components of comparative catalyst D5 is shown in Table 1.
Example 8
(1) Preparation of the support
Weighing 100g of gamma-Al2O3(Jiangsu Jiangyan chemical auxiliary factory, surface area 150m2Per g, pore volume of 0.4mL/g), and a saturated water absorption of 70mL, as measured by P2O5/Al2O33.3g of sodium dihydrogen phosphate is weighed according to the mass ratio of 0.02, added into 70mL of deionized water required by weighing to prepare a corresponding sodium phosphate solution, mixed with activated alumina and stirred uniformly, and then moved into an oven to be dried for 4 hours at 120 ℃. And roasting the dried sample at 550 ℃ for 8h to obtain the required carrier.
(2) Catalyst preparation
80mL of an aqueous solution having a palladium chloride concentration of 15g/L was measured, 75g of the carrier obtained in step (1) was taken, the carrier was dispersed in the palladium chloride solution, immersed at room temperature for 12 hours, and 12.5mL of a 5 wt% NaOH solution was added dropwise thereto and the temperature was maintained for 2 to 10 hours. Then, hydrogen gas was introduced into the suspension at 30 ℃ and the suspension was reductively activated for 4 hours under stirring at a flow rate of 30 ml/min. After filtration, the filtrate is washed with deionized water to Cl-The concentration is less than 10-6M, then at 70 ℃ under a vacuum of 1.013X 10-3～1.013×10-4Drying for 4h under the condition of Pa, and preserving under the protection of nitrogen to obtain the catalyst S8.
The mass composition of each component in the catalyst S8 is shown in Table 1.
Comparative example 6
The same as example 8 except that gamma-Al2O3No phosphorus modification. This gave comparative catalyst D6. The mass composition of the components of comparative catalyst D6 is shown in Table 1.
TABLE 1
Examples 9-16 illustrate the effectiveness of the catalyst of the present invention in the hydrogenation of anthraquinones.
Examples 9 to 16
The catalysts S1-S8 prepared in examples 1-8 were used in the hydrogenation of anthraquinones.
The anthraquinone hydrogenation evaluation device is a stirred tank continuous evaluation device and comprises a hydrogenation reactor, an oxidation reactor, a hydrogenated white soil bed, a decomposition bed, a working liquid white soil bed, a working liquid feeding pump and the like. Loading a hydrogenation catalyst into a hydrogenation reactor, and carrying out hydrogenation reaction on working solution and hydrogen under the hydrogenation condition to obtain hydrogenation solution slurry; the clear liquid of the hydrogenated liquid flowing out of the hydrogenation reactor can partially or completely pass through a hydrogenated clay bed and then contact with oxygen in the oxidation reactor for reaction to obtain an oxidation liquid containing hydrogen peroxide; the oxidizing liquid is circulated back to the hydrogenation reactor after decomposing the hydrogen peroxide by the decomposing bed; the circulating working solution can be partially or completely regenerated by the working solution clay bed and then recycled to the hydrogenation reactor.
In the anthraquinone hydrogenation reaction, the concentration of 2-amylanthraquinone in the working solution is 160g/L, the solvent is mesitylene and diisobutyl carbinol, and the water content in the working solution is 3200 ppm. The dosage of the working solution is 0.25L, the dosage of the catalyst is 1.0g, the reaction temperature is 60 ℃, the reaction pressure is 0.3MPa, and the stirring speed is 1000 r/min. The CO concentration in the hydrogen was 1 ppm.
The results of abrasion index, selectivity and hydrogenation efficiency are shown in tables 2, 3 and 4.
The catalyst wear resistance evaluation is carried out by adopting a circulating stirring type reaction kettle evaluation method, which comprises the following steps: putting a catalyst into molten wax, putting the wax in an oven to keep the wax in a molten state, allowing catalyst particles to freely settle for 12 hours, cooling and solidifying, dividing a lower-layer catalyst and an upper-layer wax layer, measuring the content of unsettled catalyst fine powder in the upper-layer wax by adopting a loss on ignition method, and quantifying the wear resistance of the catalyst by introducing a wear index: abrasion index ═ wax layer ash × total wax layer weight/catalyst loading × 100%.
The selectivity evaluation method is as follows: the content of the effective anthraquinone in the working solution after each oxidation is measured by Agilent 1260 liquid chromatography, and the ratio of the content of the effective anthraquinone to the total content of the effective anthraquinone in the working solution before hydrogenation can express the selectivity of the catalyst.
The hydrogenation efficiency (hydrogen efficiency) refers to the gram of hydrogen peroxide produced in each liter of working solution. The hydrogenation efficiency was calculated by the formula (1).
In the formula:
b-hydrogenation efficiency, g/L;
CKMnO4——KMnO4solution concentration, mol/L;
VKMnO4consumption of KMnO by titration4Volume of solution, mL;
Vhydrogenation liquidVolume of hydrogenation solution for oxidation, mL.
Method for measuring hydrogenation efficiency: taking 5mL of hydrogenated working solution, placing the hydrogenated working solution in a 50mL separating funnel, then adding 20mL of deionized water and 2mL of 2mol/L phosphoric acid into the separating funnel, introducing oxygen until the organic phase at the upper layer is changed into bright yellow, taking down the separating funnel, shaking for 1min, standing for layering, placing the water phase at the lower layer in a 150mL conical flask, repeatedly extracting the residual organic phase for 3 times by using 10mL of deionized water, still placing the extract liquid in the conical flask, adding 5mL of 20% sulfuric acid solution into the conical flask, titrating by using 0.03mol/L potassium permanganate solution until the solution is pink and does not fade for 30 s. The hydrogenation efficiency can be calculated according to the volume of the consumed potassium permanganate.
For comparison, the comparative catalysts D1-D6 prepared in comparative examples 1-6 were also evaluated in the anthraquinone hydrogenation test, and the results are shown in tables 2, 3 and 4.
TABLE 2
Catalyst and process for preparing same
Abrasion index (%), reaction time 250h
S1
0.9
S2
1.1
S3
1.3
D1
7.6
S4
1.2
D2
6.3
S5
1.1
D3
7.2
S6
1.2
D4
8.1
S7
1.2
D5
6.9
S8
0.8
D6
7.3
It can be seen from the data in table 2 that the samples of the phosphorus modified support of the present invention have better wear resistance at substantially the same composition, in combination with the composition data in table 1, compared to the comparative sample using pure alumina as the support.
TABLE 3
TABLE 4
The hydrogen efficiency is an activity parameter of the catalyst in the hydrogenation reaction of the anthraquinone, and as can be seen from the data in tables 3 and 4, the selectivity of the catalyst samples S1-S8 in 250h operation is between 91.7% and 96.1%, and the hydrogen efficiency is between 10.1% and 12.3, while the selectivity of the comparative samples D1-D6 in 250h operation is between 76.9% and 79.4%, and the hydrogen efficiency is between 5.8% and 7.1. The catalyst with palladium as main active component has obviously raised activity and selectivity, especially La and Cu as co-active component.