Amorphous calcium phosphate catalyst for use in production of 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol, and method of preparing the same

1. A method of preparing an amorphous calcium phosphate catalyst for use in production of 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol, comprising:

(a) reacting a phosphoric acid-containing solution with ammonium hydroxide, thus preparing a phosphoric acid-alkali aqueous solution;

(b) adding the phosphoric acid-alkali aqueous solution with a calcium precursor aqueous solution, thus preparing a calcium phosphate slurry, wherein preparing the calcium phosphate slurry in (b) is performed at a pH of 6-10; and

(c) thermally treating the slurry, thus obtaining an amorphous calcium phosphate catalyst used for 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol.

2. The method of claim 1 , wherein in (a), the phosphoric acid-containing solution comprises at least one selected from the group consisting of orthophosphoric acid (H 3 PO 4 ), pyrophosphoric acid (H 4 P 2 O 7 ), tripolyphosphoric acid (H 5 P 3 O 10 ), and tetrapolyphosphoric acid (H 6 P 4 O 13 ).

3. The method of claim 1 , wherein in (b), a Ca/P ratio is 1.20-1.67.

4. The method of claim 1 , wherein in (b), a Ca/P ratio is 1.20-1.30.

5. The method of claim 1 , wherein in (b), the calcium precursor comprises at least one selected from the group consisting of calcium acetate (Ca(CH 3 COO) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and calcium chloride (CaCl 2 ).

6. The method of claim 1 , wherein thermally treating in (c) is performed at 400-600° C. for 1-10 hr.

7. The method of claim 1 , further comprising producing 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol using the amorphous calcium phosphate catalyst produced in step (c).