1,3-butadiene synthesis catalyst, method for producing same, and method for producing 1,3-butadiene
A catalyst according to an embodiment is a catalyst for synthesizing 1,3-butadiene from ethanol. The catalyst contains a porous silica support made of crystalline silica, Zn, and Zr, and has a multimodal pore size distribution with a peak pore size (D micro ) of 2 nm or less and a peak pore size (D meso+macro ) of more than 2 nm.
1 . A catalyst for 1,3-butadiene synthesis for synthesizing 1,3-butadiene from ethanol, comprising a porous silica support made of crystalline silica, Zn, and Zr,
the catalyst having a multimodal pore size distribution with a first peak pore size (D micro ) of 2 nm or less and a second peak pore size (D meso+macro ) of more than 2 nm,
wherein the multimodal pore size distribution refers to a distribution of pore diameters determined from nitrogen adsorption/desorption measurements, and
wherein at least part of the Zr is bonded to silanol groups on a surface of the silica support within pores thereof, such that the Zr does not substitute for silicon atoms in a framework structure of the silica support.
2 . The catalyst for 1,3-butadiene synthesis according to claim 1 , comprising, as the Zn, ZnO supported on the silica support.
3 . The catalyst for 1,3-butadiene synthesis according to claim 1 , wherein the micropore volume (V micro ) calculated by the t-plot method is 0.03 to 0.30 cm 3 /g, and the mesopore volume (V meso ) calculated by the BJH method is 0.30 to 2.0 cm 3 /g.
4 . The catalyst for 1,3-butadiene synthesis according to claim 1 , wherein the silica support has an MFI-type framework structure.
5 . The catalyst for 1,3-butadiene synthesis according to claim 1 , wherein the molar ratio of Zn to Si is 0.001 to 0.1, and the molar ratio of Zr to Si is 0.05 to 0.5.
6 . The catalyst for 1,3-butadiene synthesis according to claim 1 , being a catalyst obtainable by mixing a zirconium alkoxide, an orthosilicic acid ester, and a first template agent together with water to prepare a zirconium silicate precursor, and mixing the zirconium silicate precursor, a zinc salt, an orthosilicic acid ester, and a second template agent together with water, followed by hydrothermal synthesis and calcination.
7 . The catalyst for 1,3-butadiene synthesis according to claim 6 , wherein the first template agent is cetyltrimethylammonium bromide, and the second template agent is tetrapropylammonium hydroxide.
8 . The catalyst for 1,3-butadiene synthesis according to claim 6 , wherein the catalyst is obtainable by performing the hydrothermal synthesis in the presence of a third template agent, followed by calcination.
9 . The catalyst for 1,3-butadiene synthesis according to claim 8 , wherein the third template agent is glycerol.
10 . The catalyst for 1,3-butadiene synthesis according to claim 1 , comprising, as the Zn, ZnO supported on the silica support, wherein at least part of the Zr is coordinated to silanol groups of the silica support through formation of at least one Si—O—Zr bond.
11 . The catalyst for 1,3-butadiene synthesis according to claim 1 , comprising, as the Zn, ZnO supported on the silica support, wherein at least part of the Zr has a coordination structure represented by Zr(OH)(OSi) 3 .
12 . The catalyst for 1,3-butadiene synthesis according to claim 1 , wherein the multimodal pore size distribution is a pore size distribution of the Log differential pore volume distribution (dV/d log D) including a first mode and a second mode, the first peak pore size (D micro ) is a peak of the first mode of 2 nm or less, and the second peak pore size (D meso+macro ) is a peak of the second mode of 20 nm or more.
13 . The catalyst for 1,3-butadiene synthesis according to claim 11 , wherein the peak of the second mode of 30 nm or more.