US3072564A - Hydrofining process - Google Patents

Description

3,072,564 HYDROFINING PROCESS Frank Clyde Stewart, Jr., and Harold Dudley Dewhirst,

Baton Rouge, La., assignors to Esso Research and Engineering Company, a corporation of Delaware No Drawing. Filed Dec. 28, 1959, Ser. No. 862,025 6 Claims. (Cl. 208-210) The present invention is concerned with the production of light oils of the highest quality. More particularly, this invention pertains to the hydrofining of light distillate oils in order to improve color and odor and reduce the aromaticity thereof.

The problem of refining and stabilizinglight distillate oils is a diflicult one. These oils are'widely used as lubrieating, diluent or solvent oil in specialty services such as in textiles, and textile processing, disinfectants and sprays for household and agricultural products. Numerous processes have been proposed for improving the quality of such light distillate oils such as extraction, clay treating, acid and caustic Washing, hydrogenation and hydrofining and combination operations involving hydrotreatficient improvement in the properties of the oil or the catalyst life of the more active catalysts has been too short to be commercially attractive. V

It is the object of this invention to provide a process for treating light distillate oils with hydrogen in the presence of a solid catalyst to form products possessing excellent color, odor and stability characteristics.

It is also the object of this invention to prepare light distillate oils of high color, low sulfur content and low aromaticity eminently suitable for specialty services in textiles, disinfectants, sprays and the like by a hydrofining treatment.

These and other objects will appear more clearly from the detailed specification and claims which follow.

It has now been found that light distillate oils particularly suited for specialty services can be prepared by hydrofining the same first at a high temperature to lower the sulfur content and reduce the aromaticity of the oil United States Patent Ofiice Patented Jan. 8, 1963 Distillation (10 mm.):

P 200 (428) 5 300 (550) 10 312 (563) 50 333 (589) 95 360 (623) F.B.P. 370 (635) sels or the second vessel may be provided with suitable heat transfer means to maintain the desired temperature in the second vessel.

The catalysts used for hydrofining light distillate oils in accordance with this invention are cobalt molybdate or mixtures of cobalt oxide and molybdenum oxide dispersed upon an alumina support or' carrier. In general, such catalysts are prepared by first forming aidsorptive alumina particles in any suitable way and then compositing molybdenum oxide and cobalt oxide therewith. The molybdenum oxide can be added as a slurry or as a solution of ammonium molybda te. 'Ihe cobalt oxide is most conveniently added as a salt such as cobalt nitrate or acetate, salts which are readily decomposed to cobalt oxide and volatile materials. The cobalt oxide and molybdenum oxide can be provided in equimolar amounts or a molecular excess of one over the other may be used. Suitable catalysts contain from about 5 to about 25 wt.

' percent of cobalt oxide and molybdenum oxide with the ratio of the former to the latter in the range of from about one to five to about five to one. Other catalysts which may be used include molybdenum oxide or sulfide Y on alumina containing about 5 to 15 wt. percent molybwith a suitable sulfiding agent such as hydrogen sulfide,

and then in a second stage at low temperatures for decolorization. It has been found that other hydrofining conditions being the same, color improvement decreases with increasing temperature and sulfur reduction and reduction in aromaticity increases with increasing tempera- Gravity, API 38.5 Flash, F 290 Color, Saybolt 14 Viscosity, SSU at 100 F 41 Sulfur, Weight percent 0.26 Aniline point, F 182 carbon disulfide, ethyl mercaptan, sour gas oil (1.0-3.0 wt. percent sulfur) or the like, preferably in the presence of hydrogen. The amount of sulfur added is preferably at least 25% of the stoichiometric quantity necessary to convert the catalytic metal oxides to the corresponding.

The hydrofining treatment is usually effected at pressures above about 200 p.s.i.g., preferably at about 600 p.s.i.g. Higher pressures of up to about 5000 p.s.i.g. can also be used but ordinarily the higher cost of equipment to Withstand such pressures and the higher cost of operation at higher pressures makes it uneconomic to use pressures above about 1000 p.s.i.g.

The temperature in the first hydrofining stage or pass is between about 450 and 650 F., preferably at about 500550 F. The temperature in the second hydrofining stage or pass is between about l50250 R, preferably about 225 F. The feed rate ineach of the hydrofining stages is about /2 to 4 v./v./hr., preferably about 2 v./v./hr. Hydrogen or hydrogen-rich treat gas .is supplied with the distillate oil feed at rates of from 50 to 2000 s .c.f. per barrel of liquid feed, but preferably at a minimum rate of 300 s.c.f. per barrel of liquid feed for operating control. The treat gas should preferably contain at least 70 vol. percent of hydrogen.

The following examples are illustrative of the present invention.

EXAMPLE 1 A non-phenol treated distillate oil produced by distween 150 and 250 F. and at essentially the same pressure as in the first reaction zone.

2. The method for upgrading light distillate petroleum oils which comprises treating said oils in admixture with tilling a 40 SSU/100 F. stream from North Louisiana 5 f g f eg g g fi f fg figg g if??? crude was treated with hydrogen in contact with 43" B 'ig g; i between 450 and 5 F catalyst pills containing 2.43 wt. percent C and 9.86 3; 3 f g 400 and 1,000 at feed wt. percent M00 dispersed on alumina. The catalyst t p f t Z d t l th was sulfided for 6 hours with a 1.4 wt. percent sulfur es 2 o an Tea 3 6 Ion contgnt Sour gas oil at F 600 psi g and 10 1o ture discharged from the first reaction zone 1n contact The treatment was effected at a pressure of with a cobalt ox1de-molybdenum oxide-alumina hydro- 600 at a feed rate of 2 VAL/hr. while charging fining catalyst at temperatures between 150 and 250 F. hydrogen treat gas at the rate of 720 s.c.f./b. of liquid and at essentially the Same Pressure as in the first reacfeed. The catalyst in the form of 8 to 20 mesh particles tiOIl (mean particle size=12 mesh) was arranged in two 3. The method as defined in claim 2 111 which the separate vessels each having an L/ D ratio of 90. temperature in the first reaction zone is about 500-550 The reaction conditions and the results of these runs F. and the temperature in the second reaction zone is are summarized in Table I. about 175-225 F;

Table 1 Run No Spec. Feed 263 264 275 266 A a B i Hydrofining conditions:

Pressure, p.s.i.g 600 600 600 600 600 600 600 600 600 Temperature, /F., #1 reactor- 375 425 475 500 500 525 575 Temperature, F., #2 reactor. 275 275 225 200 250 175 175 Feed rate, v.v./hr 2 2 2 2 2 2 Hi rate, s.c.t./b 7 720 720 720 720 720 720 720 72c L/D ratio 90 90 90 90 90 90 90 Inspections:

Gravity, API 38. 6 38. 39. 3 38. 6 38. 6 38. 5 38. 6 Flash, F- 280 280 280 280 280 280 Fire. F- 320 310 310 310 315 305 v. 100, ssU 41 41 41 41 41 41 Color, Saybolt"... +4 +9 +17 +18 29 +22 +22 Colorhold, Saybolt- 10 5 +16 +19 +19 Bromine number 1. 5 1. 8 1. 2 0. 4 1. 5 2.2 Aniline point, F 181.7 182.4 182.4 182. 8 197 182.4 182 8 Unsuliouated residue, percent- 3 90 90.0 90.0 89. 5 .0 90.0 91. 0 Corrosion, 3 hrs. at 212 F 4 J5 J-3 4 0. 15 0. 26 0. 20 0.19 0.18 0.15 0. 02 0.14 0.12 Clo d, F 36 26 28 30 2e 28 26 Alcoa stain test- D A A A Rating Fail Perfect Good Good Odor (0 1 This run was made with a catalyst of the same composition from a different manufacturer. 9 Runs designated A and B represent; correlated values for higher temperature first stage operations to bring sulfur content below 0.15 max.

8 Minimum. 4 Maximum. 5 Borderline. Satisfactory.

EXAMPLE 2 A light distillate oil (Menton 28) was hydrofined in a two-stage operation with cobalt molybdate-on-alumina catalyst. The reaction conditions, feed and product inspections are summarized in Table II below.

The foregoing specification contains a limited number of embodiments of the present invention. It will be understood however, that numerous variations are possible without departing from the scope of this invention.

What is claimed is:

1. The method for upgrading light distillate petroleum oils which comprises treating said oils in admixture with a hydrogen rich gas in a first reaction zone in contact with a hydrofining catalyst at temperatures between 450 and 650 F. and pressures of between 400 and 1000 p.s.i.g. at feed rates of /2 to 4 v./v./hr. and treating the reaction mixture discharged from the first reaction zone in contact with a hydrofining catalyst at temperatures be- 4. The method for upgrading petroleum oils having an initial boiling point of at least 425 F. and an end point of about 700 P. which comprises treating said oils in admixture with a hydrogen rich gas in a first reaction zone in contact with a hydrofining catalyst at temperatures between 450 and 650 F. and pressures of between 400 and 1000 p.s.i.g. at feed rates of /z to 4 v./v./hr. and treating the reaction mixture discharged from the first reaction zone in contact with a hydrofining catalyst at temperatures between and 250 F. and at essentially the same pressure as in the first reaction zone.

5. The method for upgrading petroleum oils having an initial boiling point of at least 425 F. and an end point of about 700 F. which comprises treating said oils in admixture with a hydrogen rich gas in a first reaction zone in contact with a cobalt oxide-molybdenum oxidealumina hydrofining catalyst at temperatures between 450 and 650 F. and pressures of between 400 and 1000 p.s.i.g. at feed rates of A2 to 4 v./v./hr. and treating the reaction mixture discharged from the first reaction zone in contact with a cobalt oxide-molybdenum oxidealumina hydrofining catalyst at temperatures between 150 and 250 F. and at essentially the same pressure as in the first reaction zone.

6. The method for upgrading light distillate petroleum oils boiling in the range of about 425 F. to about 700 E, which comprises treating said oils in admixture with a hydrogen-rich gas in a first reaction zone in contact with a cobalt oxide-molybdenum oxide hydrofining catalyst at temperatures between 500 and 550 F. and

References Cited in the file of this patent UNITED STATES PATENTS Dorrer May 3, 1938 Mason Feb. 14, 1950 Harper et a1 Apr. 12, 1955 Sweetser et a1. Nov. 6, 1956

Claims (1)

1. THE METHOD FOR UPGRADING LIGHT DISTILLATE PETROLEUM OILS WHICH COMPRISES TREATING SAID OILS IN ADMIXTURE WITH A HYDROGEN RICH GAS IN A FIRST REACTION ZONE IN CONTACT WITH A HYDROFINING CATALYST AT TEMPERATURES BETWEEN 450 AND 650*F. AND PRESSURES OF BETWEEN 400 AND 1000 P.S.I.G. AT FEED RATES OF 1/2 TO 4 V./V./HR. AND TREATING THE REACTION MIXTURE DISCHARGED FROM THE FIRST REACTION ZONE IN CONTACT WITH A HYDROFINING CATALYST AT TEMPERATURES BETWEEN 150 AND 250*F. AND AT ESSENTIALLY THE SAME PRESSURE AS IN THE FIRST REACTION ZONE.