Method for manufacturing of multi-level pore zeolite and utilization as catalyst for hydroisomerization of normal paraffins of multi-level pore zeolite prepared thereby
The present disclosure relates to a method for preparing a multi-level pore zeolite, including: (A) a step of mixing a silicon precursor, an aluminum precursor, a phosphorus precursor, a structure directing agent and water; a step of (B) adding phenylphosphonic acid, carbon black or a mixture thereof to the mixture prepared in the step (A) and mixing the same; a step of (C) crystallizing the mixture prepared in the step (B) by heat-treating the same; and a step of (D) calcining the crystallization product, and utilization of the prepared multi-level pore zeolite as a catalyst for hydroisomerization of normal paraffins. The catalyst exhibits improved isoparaffin yield when it is used as a catalyst for hydroisomerization of normal paraffins such as diesel or lube base oil by supporting an active metal component because residence time of reactants and products in the zeolite crystals are decreased due to mesopores and the proportion of external acid sites to total acid sites is low. Also, cloud point and pour point are effectively improved and high hydroisomerization reactivity is achieved without product loss.
1. A method for preparing a multi-level pore zeolite containing silicon, aluminum, and phosphorus, comprising:
(A) mixing a silicon precursor, an aluminum precursor, a phosphorus precursor, a structure directing agent and water;
(B) adding phenylphosphonic acid, carbon black or a mixture thereof to the mixture prepared in (A) and mixing the same;
(C) crystallizing the mixture prepared in (B) by heat-treating the same; and
(D) calcining the crystallization product,
wherein the multi-level pore zeolite has 10-30 vol % of micropores having a diameter of 0.1-1.9 nm based on the volume of total pores, 50-70 vol % of mesopores having a diameter of 2.0-50.0 nm based on the volume of total pores and 5-20 vol % of macropores having a diameter of 50.1-60.0 nm based on the volume of total pores.
2. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (A), the silicon precursor is one or more selected from a group consisting of silica sol, fumed silica, tetraethyl orthosilicate and tetrapropyl orthosilicate; the aluminum precursor is aluminum isopropoxide, pseudoboehmite or a mixture thereof; the phosphorus precursor is phosphoric acid, phosphorous acid or a mixture thereof; and the structure directing agent is one or more selected from a group consisting of dipropylamine, triethylamine, tripropylamine, dibutylamine and heptylamine.
3. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when the phenylphosphonic acid is added alone, a molar ratio of the water/phenylphosphonic acid is 45.5-1,000.
4. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when the phenylphosphonic acid is added alone, a molar ratio of the structure directing agent/phenylphosphonic acid is 0.9-38.0.
5. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when the phenylphosphonic acid is added alone, a molar ratio of the phosphorus precursor/phenylphosphonic acid is 1.8-40.0.
6. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when the phenylphosphonic acid is added alone, a molar ratio of total phosphorus (P 2 O 5 ) contained in the phosphorus precursor and phenylphosphonic acid/aluminum (Al 2 O 3 ) is 1.0-1.6.
7. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when the carbon black is added alone, it is added in an amount of 1-250 parts by weight based on 100 parts by weight of the multi-level pore zeolite and a weight ratio of the structure directing agent/carbon black is 0.5-50.
8. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when a mixture of the phenylphosphonic acid and the carbon black is added, a molar ratio of the water/phenylphosphonic acid is 45.5-1,000.
9. The method for preparing a multi-level pore zeolite according to claim 1 , wherein in (B), when a mixture of the phenylphosphonic acid and the carbon black is added, a molar ratio of the structure directing agent/phenylphosphonic acid is 0.9-46.0.
10. The method for preparing a multi-level pore zeolite according to claim 1 , wherein in (B), when a mixture of the phenylphosphonic acid and the carbon black is added, a molar ratio of the phosphorus precursor/phenylphosphonic acid is 1.8-40.0.
11. The method for preparing a multi-level pore zeolite according to claim 1 , wherein in (B), when a mixture of the phenylphosphonic acid and the carbon black is added, a molar ratio of total phosphorus (P 2 O 5 ) contained in the phosphorus precursor and phenylphosphonic acid/aluminum (Al 2 O 3 ) is 1.0-1.6.
12. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (B), when a mixture of the phenylphosphonic acid and the carbon black is added, the carbon black is added in an amount of 1-250 parts by weight based on 100 parts by weight of the multi-level pore zeolite.
13. The method for preparing a multi-level pore zeolite according to claim 1 , wherein, in (A), a molar ratio of aluminum (Al 2 O 3 )/silicon (SiO 2 ) is 2-20.
14. The method for preparing a multi-level pore zeolite according to claim 1 , wherein the zeolite has an accessibility factor value of (the amount of external Brønsted acid sites/the amount of total Brønsted acid sites×100)/outer surface area is 0.4 or smaller.
15. The method for preparing a multi-level pore zeolite according to claim 1 , wherein the multi-level pore zeolite containing silicon, aluminum, and phosphorus is SAPO-11.