High activity hydrotreating catalysts and processes using the same
This disclosure relates to supported multi-metallic catalysts for use in the hydrotreating of hydrocarbon feeds. The catalysts are prepared from a catalyst precursor comprised of at least one Group VIB metal, at least one Group VIII metal and an organic acid. The catalyst precursor is thermally treated to partially decompose the organic acid, then sulfided. The catalysts have a high carbon-as-carboxyl to total carbon ratio (C carboxy /C total ) as a result of a unique post-metal calcination method employed during the manufacture of the catalyst.
1. A process for hydrotreating a hydrocarbon feedstock, comprising:
contacting the feedstock with a hydrotreating catalyst under hydrotreating conditions to produce a hydrotreated effluent, wherein the hydrotreating catalyst comprises a catalyst precursor comprising:
(a) catalytically active metal-organic complex deposited in or an inorganic catalyst support, the support comprising a porous inorganic refractory selected from the group consisting of silica, alumina, alumina-silica, and crystalline silica-alumina, said metal-organic component partially oxidized for a time of from 1 minute to 1 hour at a temperature of 350° C. to 500° C.;
wherein (a) exhibits:
(i) a loss-on-ignition of greater than 1 wt. % and up to 10 wt. %; and
(ii) a carbon-as-carboxy to total residual carbon ratio (C carboxy /C total ) of from 0.10 to 0.19 as determined by X-ray photoelectron spectroscopy;
wherein loss-on-ignition is determined using a test conducted by heating a sample of the partially oxidized catalyst precursor in an oxygen-containing atmosphere for 1 hour @ 1020° F. (549° C.) and measuring weight loss after such heating;
wherein the metal portion of the partially oxidized metal organic component comprises at least one Group VIB metal and at least one Group VII metal and wherein the organic portion of the metal-organic component, prior to partial oxidation, is a hydroxycarboxylic acid selected from the group consisting of glycolic acid, lactic acid, glyceric acid, gluconic acid, malic acid, tartaric acid, mucic acid, and citric acid.
2. The process of claim 1 , wherein the catalyst precursor further comprises a phosphorus component.
3. The process of claim 2 , wherein the phosphorus component is present in an amount of from 1 to 10 wt. %, based on the bulk dry weight of the catalyst, calculated as P 2 O 5 .
4. The process of claim 1 , wherein the inorganic catalyst support is selected from the group consisting of alumina, silica, and alumina-silica.
5. The process of claim 1 , wherein the at least one Group VIB metal is Mo and the at least one Group VIII metal is Ni.
6. The process of claim 1 , wherein the catalyst precursor has a loss-on-ignition of greater than 1 wt. % and up to 8 wt. %.
7. The process of claim 1 , wherein the hydrotreating conditions include a temperature of from 302° F. to 752° F. (150° C. to 400° C.); a pressure of from 100 to 3000 psig (0.69 to 20.68 MPa); a liquid hourly space velocity or LHSV of from 0.1 to 10 h −1 ; and a hydrogen treat gas rate of from 500 to 10000 SCF/B (89 to 1780 m 3 /m 3 ).