JPWO2021112767A5 - - Google Patents

Description

The term "spinel crystalline phase" as used herein refers to a mineral of general composition AB ₂ X ₄ type. _{AB 2} Including B.

In other specific examples, a structurally improved sodium-promoted iron-based nanoparticle catalyst one-pot synthesis method is provided. The method involves mixing an aqueous solution of an iron salt (e.g., Fe(NO) ₃ ) ₃ ) with a surfactant (e.g., CTAB) in pure water, followed by a promoting base (e.g., Precipitation of the Fe phase as Fe(OH) ₂ can occur in NaOH). Subsequently, a suitable reagent such as tetraethylorthosilicate (TEOS) or aluminum isopropoxide (AIP) is added to form an oxide matrix. If TEOS is added, SiO ₂ is formed as a structural binder. The resulting precipitate, upon calcination in air, becomes an Fe spinel phase (Fe ₂ O ₃ ) promoted by an amorphous Na phase supported by an oxide matrix (eg SiO ₂ ). A suitable zeolite, such as HY zeolite, is then physically mixed with nanostructured iron to produce a hybrid catalyst.

The samples in Table 2 were precipitated with NaOH using Fe and Cu nitrates. (Excluding Fe-Cu-K/ZSM-5(25) precipitated with KOH and Fe+ZSM-5(80) precipitated with NH ₄ OH.) Then, for testing, the sample was -mixed with 5. FeNa (catalyst of the present application) is Fe ₂ O ₃ -Na, Fe (comparative example) is pure FeO ₃ and Fe-Cu (comparative example) is a mixture of iron oxide and copper oxide.

<Example 4: FeNa catalyst in silica matrix>
Figure 7 is a transmission electron microscopy (TEM) micrograph of the FeNa catalyst in a silica matrix , showing that the Fe-based nanoparticles are well dispersed throughout the 90 wt.% silica matrix.

<Example 5: Comparison of characteristics>
The characteristics of the catalyst of the present invention were compared with those of a benchmark comparative example. Table 4 shows the characteristics of FeNa, FeNa+HY, 10FeNa@SiO ₂ and Fe(Na+S)/CNF as a comparative example.

<Example 6: Olefin from _CO2 >
The use of catalysts for the conversion of _CO2 to olefins was also investigated. The FeNa catalyst, washed with deionized water, was pelletized at 40 kN and sieved to 250-500 μm particles. Then, 0.5 g of FeNa catalyst was mixed with SiC in a volume ratio of 1:1 and then fixed in a fixed bed reactor for testing. Reduction was carried out at 580° C. for 6 hours in H ₂ and under atmospheric pressure at a space velocity of 2000 ml/(gh). Activation was carried out at 300° C. for 4 hours in CO and H ₂ with H ₂ /CO ratio=2 at 10 barg and a space velocity of 2000 ml/(gh). The CO ₂ reaction was carried out at 350° C. in CO 2 and H ₂ with a H ₂ /CO ₂ ratio=3 at 15 barg and a _space velocity of 5500 ml/(gh).

Above, the FeNa catalyst achieved a light olefin yield of 10.8% at a _CO2 conversion of 46%, exhibiting a very high proportion of olefins at C2-C4 and relatively low selectivity for _CH4 and CO. It was shown that optimization for further olefin yield improvement is possible.

<Industrial applicability>
The hybrid nanoparticle iron catalysts described herein may be used in Fischer-Tropsch synthesis to convert CO ₂ or a mixture of CO and CO _{2 and H 2 as} feedstocks to produce light olefins. . The catalyst is useful in a light olefin synthesis process, the process has a high selectivity to light olefins over methane, longer chain olefins or paraffins, and the catalyst has a significantly shorter activation time. . The method of preparing the catalyst described in this application prepares the catalyst by co-precipitating the iron nanoparticle catalyst with a basic salt solution, which can facilitate the preparation of the catalyst. Additionally, the process described herein can be used to prepare light olefins, and the process has high selectivity for light olefins. Catalysts are useful in converting CO and/or CO ₂ as feedstock to other hydrocarbons such as alcohols and C5+ hydrocarbons.
It will be apparent to those skilled in the art upon reading the foregoing disclosure that various other modifications and adaptations of the invention may be made without departing from the spirit and scope of the invention, and all such modifications and adaptations are hereby incorporated by reference. should be construed as falling within the scope of the claims.

Claims (30)

A hybrid iron nanoparticle catalyst for Fischer-Tropsch synthesis reactions , comprising:
i) iron and
At least one metal selected from the group consisting of alkali metals, alkaline earth metals, transition metal elements of Groups 3 to 7 and 9 to 11 of the periodic table, lanthanides, and combinations of these elements. M and
30 to 70 wt.% of the total weight of the catalyst, comprising;
ii) 70 to 30 wt.% of the total weight of the catalyst, an aluminosilicate or silicoaluminophosphate zeolite;
The nanoparticles have a diameter of 2 to 50 nm,
The total weight percentage of the nanoparticles and the zeolite is 100wt.%,
The catalyst , wherein the zeolite is SAPO11 or SAPO34 . A hybrid iron nanoparticle catalyst for Fischer-Tropsch synthesis reactions, comprising:
i) iron and
At least one metal selected from the group consisting of alkali metals, alkaline earth metals, transition metal elements of Groups 3 to 7 and 9 to 11 of the periodic table, lanthanides, and combinations of these elements. M and
30 to 70 wt.% of the total weight of the catalyst, comprising;
ii) 70 to 30 wt.% of the total weight of the catalyst, an aluminosilicate or silicoaluminophosphate zeolite;
The nanoparticles have a diameter of 2 to 50 nm,
The total weight percentage of the nanoparticles and the zeolite is 100wt.%,
The nanoparticles containing iron further contain a halogen oxide. A hybrid iron nanoparticle catalyst for Fischer-Tropsch synthesis reactions, comprising:
i) iron and
At least one metal selected from the group consisting of alkali metals, alkaline earth metals, transition metal elements of Groups 3 to 7 and 9 to 11 of the periodic table, lanthanides, and combinations of these elements. M and
30 to 70 wt.% of the total weight of the catalyst, comprising;
ii) 70 to 30 wt.% of the total weight of the catalyst, an aluminosilicate or silicoaluminophosphate zeolite;
The nanoparticles have a diameter of 2 to 50 nm,
The total weight percentage of the nanoparticles and the zeolite is 100wt.%,
The nanoparticles containing iron further contain elements of transition metals from Groups 3 to 7 and Groups 9 to 11 of the periodic table. A hybrid iron nanoparticle catalyst for Fischer-Tropsch synthesis reactions, comprising:
i) iron and
At least one metal selected from the group consisting of alkali metals, alkaline earth metals, transition metal elements of Groups 3 to 7 and 9 to 11 of the periodic table, lanthanides, and combinations of these elements. M and
30 to 70 wt.% of the total weight of the catalyst, comprising;
ii) 70 to 30 wt.% of the total weight of the catalyst, an aluminosilicate or silicoaluminophosphate zeolite;
The nanoparticles have a diameter of 2 to 50 nm,
The total weight percentage of the nanoparticles and the zeolite is 100wt.%,
The nanoparticles containing iron are SiO ₂ Catalyst dispersed in a matrix. 5. Catalyst according to any one of the preceding claims, wherein the metal M constitutes from 10 to 50 wt.% of the weight of the iron-containing nanoparticles. 6. The catalyst according to _claim 1 , wherein the nanoparticles have a spinel crystalline phase with the chemical formula _FeM2O4 . The zeolite is a pentasil zeolite or a faujasite zeolite, or the zeolite is selected from the group consisting of zeolite X, ZSM-5, zeolite Y, ZSM-12, ZSM-22, and HY zeolite. , a catalyst according to any one of claims 1 to 6 . Catalyst according to any one of claims 1 to 7 , wherein the molar ratio of alumina to silica in the zeolite is from 1 :2 to 1:90. Catalyst according to any one of claims 1 to 8 , wherein the weight ratio of the zeolite to the iron-containing nanoparticles is from 1 :0.5 to 1:10. 3. The catalyst of claim 2 , wherein the halogen oxide is present in an amount of 0.1 to 50 wt.% of the weight of the nanoparticles. 4. A catalyst according to claim 3 , wherein the molar ratio of iron to said transition metal is from 1:1 to 50:1. A method for producing a hybrid nanoparticle iron catalyst for a Fischer-Tropsch synthesis reaction , comprising:
i) mixing a solution containing an iron salt with an aqueous surfactant to form a mixture;
ii) Salts of elements selected from the group consisting of alkali metals, alkaline earth metals, transition metal elements of groups 3 to 7 or 9 to 11 of the periodic table, lanthanides, and combinations of these elements. (ii) adding a solution of a basic salt comprising: to the mixture of step (i) to form a precipitate;
iii) heating the precipitate of step (ii) in the presence of air or oxygen;
iv) mixing the precipitate of step (iii) with an aluminosilicate or silicoaluminophosphate zeolite to obtain a hybrid iron catalyst. 13. The method of claim 12 , wherein the salt of the element comprises a hydroxide, carbonate, or bicarbonate anion. 14. A method according to claim 12 or 13 , wherein the molar ratio of the iron to the element of the basic salt is from 1:2 to 1:25. 15. A method according to any one of claims 12 to 14 , wherein the heating step of step (ii) is carried out at a temperature of 300<0>C to 600<0>C or for 1 to 10 hours. The iron salt is a divalent iron salt or a trivalent iron salt, or the iron salt is a nitrate, chloride, fluoride, bromide, iodide, phosphate, pyrophosphate and perchlorate. 16. A method according to any one of claims 12 to 15 , comprising an anion selected from the group consisting of. The surfactant is an ionic surfactant, or the surfactant comprises an anion selected from the group consisting of halides, sulfonates, sulfates, phosphates and carboxylates. The method according to any one of items 12 to 16 . 18. A method according to any one of claims 12 to 17 , wherein the molar ratio of iron to said surfactant is from 1:0.5 to 1:15. 19. The method according to any one of claims 12 to 18 , further comprising, before step (iii), collecting the precipitated nanoparticle catalyst and drying the precipitated nanoparticle catalyst in air. Method. 20. The method of claim 19 , wherein recovery of the precipitated nanoparticle catalyst is performed by centrifugation and/or filtration. 21. The method of any one of claims 12 to 20 , further comprising adding a solution of a salt of a transition metal to the mixture of step (i) before step (ii). 21. A method according to any one of claims 12 to 20 , further comprising introducing the mixture of step (i) into a solution of silicate prior to step (ii). 23. The method of claim 22 , wherein the silicate contains an alkoxy group of 2 to 15 carbon atoms. 24. A method according to claim 22 or 23 , wherein the molar ratio of iron to said silicate is from 1:1 to 1:50. A light olefin manufacturing process,
i) heating the catalyst according to any one of claims 1 to 11 in the presence of a gas comprising one or more carbon oxides and hydrogen to activate the catalyst;
ii) contacting said catalyst activated in said step (i) with a gaseous fluid comprising one or more carbon oxides and hydrogen, partially or completely converting said one or more carbon oxides into said light olefins; step (ii) of converting into
The light olefin contains 2 to 4 carbon atoms,
A process in which methane is not included in the light olefins or constitutes less than 20% of the light olefins. Said step (i) is carried out at a temperature of from 200°C to 350°C, or said step (ii) is carried out at a temperature of from 200°C to 450°C, or said step (i) is carried out at a pressure of from 5 to 30 bar. 26. The process according to claim 25 , wherein step (ii) is carried out at a pressure of 5 to 50 bar. 27. A process according to claim 25 or 26 , wherein the space velocity of the gaseous fluid in step (ii) is between 1500ml/gh and 5000ml/gh. 28. A process according to any one of claims 25 to 27 , wherein the molar ratio of hydrogen to said one or more carbon oxides of said gas is from 4:1 to 1:3. 29. The method of claim 25 to 28 , further comprising reducing the catalyst of any one of claims 1 to 11 by contacting the catalyst with a flow of hydrogen gas prior to step (i). The process according to any one of the preceding paragraphs. 30. A process according to any one of claims 25 to 29 , wherein the carbon oxide of the gaseous fluid of step (ii) is carbon dioxide .