Claims
- 1. A catalyst composition having enhanced mechanical strength and activity, and displaying marked resistance to sulfation, consisting essentially of (i) titanium dioxide, (ii) the sulfate of calcium, barium, strontium or magnesium, and (iii) up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers.
- 2. The catalyst composition as defined by claim 1, the amount by weight of the titanium dioxide therein, relative to the total weight of (i) and (ii) thereof, ranging from about 60 to about 99%.
- 3. The catalyst composition as defined by claim 2, the amount by weight of the titanium dioxide therein, relative to the total weight of (i) and (ii) thereof, ranging from about 80 to about 99%.
- 4. A catalyst composition having improved mechanical strength and activity, and displaying marked resistance to sulfation, comprising (i) titanium dioxide, (ii) the sulfate of calcium, barium, strontium or magnesium, and (iii) up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers, the amount by weight of the alkaline earth metal sulfate therein, relative to the total weight of (i) and (ii) thereof, ranging from about 1 to about 40%.
- 5. The catalyst composition as defined by claim 3, the amount by weight of the alkaline earth metal sulfate therein, relative to the total weight of (i) and (ii) thereof, ranging from about 1 to about 20%.
- 6. A process for the preparation of the catalyst composition as defined by claims 1 or 4, comprising successively impregnating a titanium dioxide shaped catalyst substrate containing up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers with both a donor compound for the sulfate anion and with a donor compound for the calcium, barium, strontium or magnesium cation, and then optionally drying and calcining said impregnated TiO.sub.2 shaped catalyst substrate at a temperature ranging from about 300.degree. C. to about 900.degree. C.
- 7. A process for the preparation of the catalyst composition as defined by claims 1 or 4, which comprises (1) malaxating an intimate admixture comprising (i) from about 1 to about 40% by weight of water, (ii) from about 0 to about 15% by weight of a shaping additive, (iii) up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers and (iv) from about 45 to about 99% by weight of a powder including a donor compound for the calcium, barium, strontium or magnesium cation, and sulfate anion containing titanium dioxide resulting from the sulfuric acid acidulation of ilmenite, with the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.01 to about 0.15, the ratio by weight of the alkaline earth metal to the titanium dioxide therein ranging from about 0.004 to about 0.20, and the ignition weight loss of such powder ranging from about 1 to about 50%, (2) next shaping the mixture of malaxation into catalyst form, and (3) thence optionally drying and calcining said resulting shaped catalyst at a temperature ranging from about 300.degree. C. to about 900.degree. C.
- 8. The process as defined by claim 7, the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.05 to about 0.10, and the ratio by weight of the alkaline earth metal to the titanium dioxide therein ranging from about 0.02 to about 0.15.
- 9. The process as defined by claim 7, said calcination (3) being at a temperature ranging from about 350.degree. C. to about 800.degree. C.
- 10. The process as defined by claim 6, said donor compound for the sulfate anion being sulfuric acid or a sulfate which is soluble in aqueous solution, said donor compound for the alkaline earth metal cation being a salt which is soluble in aqueous solution, and said successive impregnations being such that the ratio by weight of the SO.sub.4 provided, to the TiO.sub.2, ranges from about 0.01 to about 0.15, and the ratio by weight of the alkaline earth metal provided, also to the TiO.sub.2, ranges from about 0.004 to about 0.20.
- 11. The process as defined by claim 10, said donor compound for the sulfate anion being ammonium sulfate or hydroxylamine sulfate, and said donor compound for the alkaline earth metal cation being a nitrate, chloride or acetate of calcium, barium, strontium or magnesium.
- 12. The process as defined by claim 10, said ratio by weight of SO.sub.4 to TiO.sub.2 ranging from about 0.05 to about 0.10, and said ratio by weight of alkaline earth metal to TiO.sub.2 ranging from about 0.02 to about 0.15.
- 13. A process for the preparation of the catalyst composition as defined by claims 1 or 4, which comprises (1) malaxating an intimate admixture comprising (i) from about 1 to about 40% by weight of water, (ii) from about 0 to about 15% by weight of a shaping additive, (iii) up to about 30% by weight of silica, alumina, clays, silicate, titanium sulfate, or ceramic fibers and (iv) from about 45 to about 99% by weight of a powder having an LOI ranging from about 1 to about 50% and including poorly crystalline and/or amorphous titanium dioxide, and either calcium, barium, strontium or magnesium sulfate, or admixture of donor compounds together providing both sulfate anion and calcium, barium, strontium or magnesium cation, with the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.01 to about 0.15, the ratio by weight of the alkaline earth metal to the titanium dioxide therein ranging from about 0.004 to about 0.20, (2) next shaping the mixture of malaxation into catalyst form, and (3) thence optionally drying and calcining said resulting shaped catalyst at a temperature ranging from about 300.degree. C. to about 900.degree. C.
- 14. The process as defined by claim 13, the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.05 to about 0.10, and the ratio by weight of the alkaline earth metal to the titanium dioxide therein ranging from about 0.02 to about 0.15.
- 15. The process as defined by claim 13, said calcination (3) being at a temperature ranging from about 350.degree. C. to about 800.degree. C.
- 16. A process for the preparation of the catalyst composition as defined by claims 1 or 4, which comprises (1) malaxating an intimate admixture comprising (i) from about 1 to about 40% by weight of water, (ii) from about 0 to about 15% by weight of a shaping additive, (iii) up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers and (iv) from about 45 to about 99% by weight of a sulfate anion containing titanium dioxide powder resulting from the sulfuric acid acidulation of ilmenite, with the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.01 to about 0.15 and the ignition weight loss of such powder ranging from about 1 to about 50%, (2) next shaping the mixture of malaxation into catalyst form, (3) then optionally drying and optionally calcining said resulting shaped catalyst at a temperature ranging from about 300.degree. C. to about 900.degree. C., (4) next impregnating said shaped catalyst with a calcium, barium, strontium or magnesium cation donor compound which is soluble in aqueous solution, and (5) thence optionally drying and calcining said impregnated shaped catalyst at a temperature ranging from about 300.degree. C. to about 900.degree. C.
- 17. The process as defined by claim 16, the ratio by weight of SO.sub.4 to TiO.sub.2 in said powder ranging from about 0.05 to about 0.10.
- 18. The process as defined by claim 16, said calcinations (3) and (5) being at a temperature ranging from about 350.degree. C. to about 800.degree. C.
- 19. A process for the preparation of the catalyst composition as defined by claims 1 or 4, which comprises sulfating a titanium dioxide shaped catalyst substrate containing up to about 30% by weight of silica, alumina, clays, silicates, titanium sulfate, or ceramic fibers, said TiO.sub.2 shaped substrate comprising calcium, barium, strontium or magnesium cations, and thence optionally drying and calcining said sulfated shaped catalyst at a temperature ranging from about 300.degree. C. to about 900.degree. C.
- 20. The process as defined by claim 19, said sulfation being carried out with a mixture of sulfur dioxide and air, at a temperature ranging from about 250.degree. C. to about 550.degree. C.
- 21. The catalyst composition as defined by claims 1 or 4, having a specific surface area ranging from about 5 to about 300 M.sup.2 /g.
- 22. The catalyst composition as defined by claims 1 or 4, having a total pore volume ranging from about 0.05 to 0.5 cm.sup.3 /g.
- 23. The catalyst composition as defined by claims 1 or 4, wherein the sulfate is calcium sulfate.
- 24. The catalyst composition as defined by any of claims 1, 2, 3, 4 or 5, the same having been shaped and activated by calcination.
Priority Claims (1)
Number |
Date |
Country |
Kind |
81 05029 |
Mar 1981 |
FRX |
|
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 353,219, filed Mar. 1, 1982, now U.S. Pat. No. 4,422,958.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4269735 |
Leach |
May 1981 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
1943759 |
Apr 1971 |
DEX |
53-10368 |
Jan 1978 |
JPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
353219 |
Mar 1982 |
|