A production process of an economical catalyst for HPPO process

Abstract

The present invention provides a production process of an economical catalyst for HPPO process, and relates to the technical field of catalysts. The present invention is to stir after mixing tetrapropylammonium hydroxide, a silicon source, and deionized water to obtain a synthetic liquid; after the synthetic liquid is left to stand for crystallization for 1-3 days, the crystallized product is taken out by quenching; after tetrapropylammonium hydroxide, an alcohol amine and water are mixed to obtain a mixed solution; tetraethyl orthosilicate is added to the mixed solution described in step (3), tetrabutyl titanate is added dropwise after hydrolysis for 0.5-2h, and a uniform gel is prepared by stirring, and then the crystallized product is added, stirred at room temperature for 12-24h, and then hydrothermally crystallized for 1-5 days at a temperature of 150-180°C; finally, the hydrothermally crystallized solution is centrifuged, washed, and dried, and then roasted to obtain an economical catalyst for HPPO process. The present invention effectively reduces the processing cost of the catalyst for HPPO process.

Description

Technical Field

[0001] The invention relates to the technical field of catalysts, and in particular to a production process of an economical catalyst for a HPPO process. Background Art

[0002] Titanium silicate molecular sieve is a new type of heteroatom molecular sieve developed in the early 1980s. At present, TS-1 with MFI structure, TS-2 with MEL structure, MCM-22 with MWW structure and TS-48 with larger pore structure have been synthesized. Among them, TS-1 titanium silicate molecular sieve developed and synthesized by Enichem Company of Italy is a new type of titanium silicate molecular sieve with excellent catalytic selective oxidation performance formed by introducing transition metal element titanium into the molecular sieve framework with ZSM-5 structure.

[0003] TS-1 not only has the catalytic oxidation effect of titanium, but also has the shape selectivity and excellent stability of ZSM-5 molecular sieve. Using TS-1 molecular sieve as a catalyst can catalyze various types of organic oxidation reactions, such as epoxidation of olefins, partial oxidation of alkanes, oxidation of alcohols, hydroxylation of phenols, ammoxidation of cyclic ketones, etc. Since TS-1 molecular sieve can use pollution-free low-concentration hydrogen peroxide as an oxidant in the oxidation reaction of organic matter, it avoids the problems of complex oxidation process and environmental pollution. It has the unparalleled advantages of energy saving, economy and environmental friendliness of traditional oxidation systems, and has good reaction selectivity. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a production process of an economical catalyst for HPPO process. The production process of the economical catalyst for HPPO process of the present invention comprises the following steps:

[0005] (1) After tetrapropylammonium hydroxide and a silicon source are mixed, deionized water is added and dispersed uniformly to obtain a synthetic solution;

[0006] (2) allowing the synthetic solution to stand for crystallization for 1-3 days, and then rapidly cooling and removing the crystallized product;

[0007] (3) mixing tetrapropylammonium hydroxide and alcoholamine, and adding water to dissolve to obtain a mixed solution;

[0008] (4) adding tetraethyl orthosilicate to the mixed solution described in step (3), hydrolyzing for 0.5 to 2 hours, then adding tetrabutyl titanate dropwise, stirring to form a uniform gel, then adding the crystallized product described in step (2), stirring at room temperature for 12 to 24 hours, and then hydrothermally crystallizing at a temperature of 150 to 180° C. for 1 to 5 days;

[0009] (5) The solution hydrothermally crystallized in step (4) is centrifuged, washed, dried, and then calcined to obtain an economical catalyst for the HPPO process.

[0010] Preferably, the silicon source in step (1) is one or two of silica sol, C-type silica gel, and white carbon black.

[0011] Preferably, in step (1), the weight portion of tetrapropylammonium hydroxide is 0.6-4, and the weight portion of the silicon source is 1.

[0012] Preferably, the stirring time in step (1) is 12-24 hours.

[0013] Preferably, the temperature for standing crystallization in step (2) is 50-100°C.

[0014] Preferably, the alcoholamine in step (3) is one of ethanolamine, diethanolamine and triethanolamine.

[0015] Preferably, in step (3), the weight portion of tetrapropylammonium hydroxide is 0.5-4, and the weight portion of alcoholamine is 0.08-1.

[0016] Preferably, the amount of the crystallized material added is 0.3 to 1.7 parts by weight.

[0017] Preferably, the drying temperature in step (5) is 100-120° C., and the drying time is 6-12 hours.

[0018] Preferably, the calcination temperature in step (5) is 450-550° C., and the calcination time is 4-6 hours.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention adopts low-cost tetrapropylammonium hydroxide as a template agent and alcoholamine as an alkali source to form a cheap synthesis system, thereby reducing the synthesis cost. The present invention adds an appropriate amount of ZSM-5 colloidal precursor as a molecular sieve seed to accelerate the crystallization speed and obtain a catalyst with a smaller grain size; the seed preparation process of the present invention is simple, thereby effectively reducing the process cost. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the present invention clearer, the preferred embodiments of the present invention are further described in detail in conjunction with the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Example 1

[0023] A production process of an economical catalyst for HPPO process, the specific steps are as follows:

[0024] (1) 1 part by weight of tetrapropylammonium hydroxide and 1 part by weight of type C silica gel were mixed, and an appropriate amount of deionized water was added. After mixing, the mixture was stirred at room temperature for 20 hours to obtain a synthetic solution;

[0025] (2) the synthetic solution was allowed to stand at 50° C. for 2 days for crystallization, and then the crystallized product was rapidly cooled and taken out;

[0026] (3) mixing 2 parts by weight of tetrapropylammonium hydroxide, 0.4 parts by weight of ethanolamine and an appropriate amount of water to obtain a mixed solution;

[0027] (4) adding 20 parts by weight of tetraethyl orthosilicate to the mixed solution described in step (3), hydrolyzing for 1.5 hours, and then adding 0.5 parts by weight of tetrabutyl titanate dropwise, stirring to form a uniform gel, and then adding 1 part by weight of the crystallized product described in step (2), stirring at room temperature for 20 hours, and then hydrothermally crystallizing at a temperature of 170° C. for 3 days;

[0028] (5) The solution hydrothermally crystallized in step (4) is centrifuged, washed, dried, and then calcined to obtain an economical catalyst for HPPO process, wherein the drying temperature is 120° C. and the drying time is 10 h; wherein the calcination temperature is 450° C. and the calcination time is 5 h.

[0029] Example 2

[0030] A production process of an economical catalyst for HPPO process, the specific steps are as follows:

[0031] (1) 1 part by weight of tetrapropylammonium hydroxide and 1 part by weight of type C silica gel were mixed, an appropriate amount of deionized water was added, and the mixture was stirred at room temperature for 15 hours to obtain a synthetic solution;

[0032] (2) allowing the synthetic solution to stand for crystallization at 100° C. for 1 day, and then rapidly cooling and removing the crystallized product;

[0033] (3) 2 parts by weight of tetrapropylammonium hydroxide and 0.3 parts by weight of diethanolamine were mixed, and an appropriate amount of water was added, and the mixture was thoroughly mixed to obtain a mixed solution;

[0034] (4) adding 20 parts by weight of tetraethyl orthosilicate to the mixed solution described in step (3), hydrolyzing for 2 hours, and then adding 0.5 parts by weight of tetrabutyl titanate dropwise, stirring to form a uniform gel, and then adding 1 part by weight of the crystallized product described in step (2), stirring at room temperature for 24 hours, and then hydrothermally crystallizing at a temperature of 150° C. for 5 days;

[0035] (5) The solution hydrothermally crystallized in step (4) is centrifuged, washed, dried, and then calcined to obtain an economical catalyst for HPPO process, wherein the drying temperature is 120° C. and the drying time is 12 h; wherein the calcination temperature is 450° C. and the calcination time is 6 h.

[0036] Example 3

[0037] A production process of an economical catalyst for HPPO process, the specific steps are as follows:

[0038] (1) 1 part by weight of tetrapropylammonium hydroxide and 1 part by weight of type C silica gel were mixed, an appropriate amount of deionized water was added, and the mixture was stirred at room temperature for 12 hours to obtain a synthetic solution;

[0039] (2) the synthetic solution was allowed to stand at 50° C. for 3 days for crystallization, and then the crystallized product was taken out by rapid cooling;

[0040] (3) 2 parts by weight of tetrapropylammonium hydroxide and 0.2 parts by weight of triethanolamine are mixed, and then an amount of water is added to obtain a mixed solution;

[0041] (4) adding 20 parts by weight of tetraethyl orthosilicate to the mixed solution described in step (3), hydrolyzing for 0.5 h, and then adding 0.5 parts by weight of tetrabutyl titanate dropwise, stirring to form a uniform gel, and then adding 1 part by weight of the crystallized product described in step (2), stirring at room temperature for 12 h, and then hydrothermally crystallizing at a temperature of 180° C. for 5 days;

[0042] (5) The solution hydrothermally crystallized in step (4) is centrifuged, washed, dried, and then calcined to obtain an economical catalyst for HPPO process, wherein the drying temperature is 100° C. and the drying time is 12 h; wherein the calcination temperature is 550° C. and the calcination time is 4 h.

[0043] The catalysts prepared in Examples 1 to 3 were tested for performance, as follows:

[0044] The reaction temperature was 40°C, the pressure was 3.0 MPa, the feed ratio of propylene to H2O2 was 3:1 (molar ratio), and the mass space velocity of propylene was 1.2 h -1 .

[0045] Hydrogen peroxide conversion rate % PO selectivity% Example 1 98.5 99.9 Example 2 98.3 99.8 Example 3 98.0 99.5

[0046] The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A production process of an economical catalyst for HPPO process, characterized in that: The following steps are involved: (1) After tetrapropylammonium hydroxide and a silicon source are mixed, deionized water is added and dispersed uniformly to obtain a synthetic solution; (2) allowing the synthetic solution to stand for crystallization for 1-3 days, and then rapidly cooling and removing the crystallized product; (3) mixing tetrapropylammonium hydroxide and alcoholamine, and adding water to dissolve to obtain a mixed solution; (4) adding tetraethyl orthosilicate to the mixed solution described in step (3), hydrolyzing for 0.5 to 2 hours, then adding tetrabutyl titanate dropwise, stirring to form a uniform gel, then adding the crystallized product described in step (2), stirring at room temperature for 12 to 24 hours, and then hydrothermally crystallizing at a temperature of 150 to 180° C. for 1 to 5 days; (5) The solution hydrothermally crystallized in step (4) is centrifuged, washed, dried, and then calcined to obtain an economical catalyst for the HPPO process.

2. The production process according to claim 1, characterized in that: The silicon source in step (1) is one or two of silica sol, C-type silica gel, and white carbon black.

3. The production process according to claim 1, characterized in that: In step (1), the weight portion of tetrapropylammonium hydroxide is 0.6-4, and the weight portion of the silicon source is 1.

4. The production process according to claim 1, characterized in that: The stirring time in step (1) is 12-24h.

5. The production process according to claim 1, characterized in that: The temperature for standing still for crystallization in step (2) is 50-100°C.

6. The production process according to claim 1, characterized in that: The alcoholamine in step (3) is one of ethanolamine, diethanolamine and triethanolamine.

7. The production process according to claim 1, characterized in that: In step (3), the weight portion of tetrapropylammonium hydroxide is 0.5-4, and the weight portion of alcoholamine is 0.08-1.

8. The production process according to claim 1, characterized in that: The amount of the crystallized material added is 0.3 to 1.7 parts by weight.

9. The production process according to claim 1, characterized in that: The drying temperature in step (5) is 100-120° C. and the drying time is 6-12 hours.

10. The production process according to claim 1, characterized in that: The calcination temperature in step (5) is 450-550° C. and the calcination time is 4-6 hours.