Treating of catalyst carrier, fischer-tropsch catalysts and method of preparation thereof
A method for the preparation of a modified catalyst support comprising: (a) treating a bare catalyst support material with an aqueous solution or dispersion of one or more titanium metal sources and one or more carboxylic acids; and (b) drying the treated support, and (c) optionally calcining the treated support. Also provided are catalyst support materials obtainable by the methods, and catalysts prepared from such supports.
1. A method for the preparation of a modified catalyst support comprising:
a. treating a bare catalyst support material with an acidic aqueous solution or dispersion to form the modified support, the acidic aqueous solution or dispersion comprising:
one or more titanium metal sources; and
one or more carboxylic acids;
b. drying the modified support; and
c. calcining the modified support,
wherein at least a portion of the one or more carboxylic acids is partially decomposed on the modified catalyst support during at least one of the drying and the calcining of the modified support, and the modified support comprises from about 11% to about 30% by weight TiO 2 .
2. The method of claim 1 , wherein the method of treating is impregnating.
3. The method of claim 1 , wherein the titanium metal source is titanium (IV) bis(ammoniumlactato)dihydroxide.
4. The method of claim 1 , wherein the one or more carboxylic acids comprises citric acid.
5. The method of claim 1 , wherein the one or more carboxylic acids comprises lactic acid.
6. The method of claim 1 , wherein the bare catalyst support material is a refractory oxide.
7. The method of claim 6 , wherein the refractory oxide is silica.
8. The method of claim 1 , wherein the modified catalyst support is a modified Fischer-Tropsch catalyst support.
9. The method of claim 1 wherein the modified catalyst support is treated to form a catalyst precursor, the method further comprising:
d. depositing a solution or suspension comprising at least one catalyst metal precursor and a complexing/reducing agent onto the modified catalyst support to form the catalyst precursor;
e. optionally drying the catalyst precursor; and
f. calcining the catalyst precursor.
10. The method of claim 9 , wherein the catalyst metal precursor is a cobalt-containing precursor.
11. The method of claim 10 , wherein the cobalt-containing precursor is cobalt nitrate.
12. The method of claim 9 , wherein the complexing/reducing agent is one or more polar organic solvents.
13. The method of claim 12 , wherein the polar organic solvent is one or more carboxylic acids.
14. The method of claim 13 , wherein the carboxylic acid comprises citric acid.
15. The method of claim 9 , wherein the calcination is carried out in an oxygen-containing atmosphere.
16. The method of claim 1 , wherein the one or more carboxylic acids are present in the acidic aqueous solution or dispersion in an amount of about 5% w/v to about 20% w/v.
17. The method of claim 1 , wherein a pH of the acidic aqueous solution or dispersion is from about 3.0 to about 3.5.
18. The method of claim 1 , wherein the bare catalyst support material is in the form of a structured shape.
19. The method of claim 1 , wherein the bare catalyst support material is in the form of pellets.
20. The method of claim 1 , wherein the bare catalyst support material is in the form of a powder.