Oxychlorination catalyst and method for preparing the same
A catalyst for oxychlorination according to the present invention contains alumina and copper, and a content of copper is in the range from 5 to 20% by weight calculated as that of CuO, while a content of halogen is not more than 5% by weight. The catalyst is produced by the following steps (a) to (c): (a) preparing a slurry for spray-drying by adding an acid and an aqueous solution of cupric nitrate in a pseudo-boehmite alumina slurry; (b) spray-drying the slurry; and (c) burning the particles obtained in step (b).
1. A method of producing a catalyst for oxychlorination comprising alumina and copper, the method comprising the following steps (a) to (c):
(a) preparing a slurry for spray-drying by adding, to a pseudo-boehmite alumina slurry, nitric acid in a range from 0.001 to 0.1 moles per mole of Al 2 O 3 in the slurry, and an aqueous solution of cupric nitrate;
(b) spray-drying the slurry; and
(c) calcining particles obtained in the step (b),
wherein a content of copper is in the range from 5 to 20% by weight calculated as CuO, and a content of chlorine is 0.5% by weight or less.
2. The method of producing the catalyst for oxychlorination according to claim 1 , wherein pH of the slurry for spray-drying is in the range from 3 to 5.
3. The method of producing the catalyst for oxychlorination according to claim 1 , wherein an aqueous solution of an alkaline earth metal nitrate is added in the step (a).
4. The method of producing the catalyst for oxychlorination according to claim 1 , wherein an aqueous solution of a rare earth metal nitrate is added in the step (a).
5. The method of producing the catalyst for oxychlorination according to claim 1 , wherein an aqueous solution of an alkaline metal nitrate is added in the step (a).
6. The method of producing the catalyst for oxychlorination according to claim 1 , wherein the nitric acid has a concentration in a range of 10 to 35% by weight, and a pH of the pseudo-boehmite alumina slurry is in a range from 2 to 6.
7. A method of producing a catalyst for oxychlorination, comprising the steps (a) to (d):
(a) preparing a slurry for spray-drying by adding, to a pseudo-boehmite alumina slurry, nitric acid in a range from 0.001 to 0.1 moles per mole of Al 2 O 3 in the slurry, and an aqueous solution of cupric nitrate;
(b) adding to the slurry an alkaline earth metal salt, a rare earth metal salt and an alkaline salt;
(c) spray-drying the slurry; and
(d) calcining particles obtained in the step (c),
wherein the catalyst consists essentially of alumina; copper in a range from 5 to 20% by weight calculated as CuO; the alkaline earth metal salt in a range from 0.1 to 6% by weight; the rare earth meal salt in a range from 0.1 to 6% by weight; and the alkaline salt in a range from 0.1 to 3% by weight, and a content of chlorine in the catalyst is 0.5% by weight or less.
8. The method of producing the catalyst for oxychlorination according to claim 7 , wherein a pseudo-boehmite alumina has an average length in a range from 1 to 10 nm, and an average width in a range from 0.5 to 3 nm.
9. The method of producing the catalyst for oxychlorination according to claim 8 , wherein spherical particles are obtained by spraying-drying the slurry, said spherical particles having an average diameter in a range from 50 to 80 μm.
10. The method of producing the catalyst for oxychlorination according to claim 9 , wherein the spherical particles are calcined in a range from 350 to 850 ° C.
11. The method of producing the catalyst for oxychlorination according to claim 7 , wherein the nitric acid has a concentration in a range of 10 to 35% by weight, and a pH of the pseudo-boehmite alumina slurry is in a range from 2 to 6.
12. A method of producing a catalyst for oxychlorination, comprising the steps (a) to (d):
(a) preparing a slurry for spray-drying by adding, to a pseudo-boehmite alumina slurry, nitric acid in a range from 0.001 to 0.1 moles per mole of Al 2 O 3 in the slurry, and an aqueous solution of cupric nitrate;
(b) adding to the slurry an alkaline earth metal salt, a rare earth metal salt and an alkaline salt;
(c) spray-drying the slurry; and
(d) calcining particles obtained in the step (c),
wherein the catalyst consists essentially of alumina; copper in a range from 5 to 20% by weight calculated as CuO; the alkaline earth metal salt in a range from 0.1 to 6% by weight; the rare earth meal salt in a range from 0.1 to 6% by weight; and the alkaline salt in a range from 0.1 to 3% by weight, and a content of chlorine in the catalyst is 0.5% by weight or less, and
wherein chlorine is substantially absent in the catalyst.