DE1470636A1 - Process for reducing the sulfur content of a sulfur-containing heavy hydrocarbon oil - Google Patents

Description

■ '' ^: "

DR. ELISABETH JUNQ, DR. VOLKER VOSSIUS. DIPL.-ING. GERHARD COLDEWEY

" ^TENTANWÄUe 1470636

t MÖNCHEN 23 · 8 1E O ES 8 T RA88E J ». TELEPHONE 34I0B7. TEl EQ a AM M-ADUE88 £ i INVENT / MONCHEN

* 5452 JA 2 O. J [III11953 · *

P 1 * 1 70 636.6 (S 7 & 836 IVo / 23b)

SHELL RESBAHOH LIMITED,

I: '

London / England

ⁿ . Process for reducing the sulfur content of a heavy hydrocarbon oil containing venison oil

Priority:

April 6, 1961 (Prov, Spec ·) υηά 26 · Pebruary 1962 (Compl-Speo *)

The Erfindtinß relates to a method for Harabsetztxng dee Schwofelgehalts a sulfur-containing heavy carbon ~ wasaerBtoff œLa, of which at least 50 VoI.5 ^ 250 ⁰ C bieden.

The process is characterized by the fact that the oil is in in a known manner with an oxidizing agent Formation of products is dealt with, both of which are sour substance as well as sulfur, and that these products, in particular in the form of sulphones by means of a thermal aftertreatment at least «um Some of them are decomposed with the formation of hydrocarbons and volatile sulfur compounds «

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«MeCHECKKONTO« MÖNCHEN IMTt. BANK ACCOUNTS DEUTSCHE BANK AO MÖNCHEN, IKOPOLOST «. Tl ₁ KTO. NB. «Λ67Μ

809811/0967 BATH ORIGINAL

Eo is believed to be the sulfur-carbon bonds The sulfur-containing molecules are carefully washed through the formation of the oxidation products and then through the subsequent treatment at such temperatures that the aura of degradation of the hydrocarbons present in the oil is not sufficient.

An advantage of the process of the invention over the methods which provide a treatment of hydrocarbon oil fractions with oxidizing agents of various types and subsequent removal of the oxidation products duroh acidic heat, solvent extraction, fractional distillation, extractive distillation, adsorption or a combination of such methods is that in the erfindungogemänsan desulfurization no grösaeren losses ^v of valuable öllcomponenten occur "It's verifiable dowel particular the hydrocarbon components of the sulfur-bearing molecules" the present invention 1st therefore particularly favorable for use Suer treatment of hydrocarbon oils, in which many molecules Sohwefelatom _i contain " Another advantage of the present invention is that it can be applied to sulfur-containing heavy hydrocarbon oils, for which catalytic hydroenteohulfur-brown products are either very costly or for that. especially. Sohwefolverbindungen contained therein unsuitable Bind »'; . ,

8 0 9 8 11/0967

BATH ORIGINAL

Preferably, the oxidizing treatment should only up to Lead formation of sulphones without further oxidation to derivatives of sulphonic acid taking place. The presence Such acid derivatives can namely in the thermal aftertreatment due to the formation of sulfuric acid and the associated sludge and coke formation have an unfavorable effect. Disulfide formation must also be avoided will,,

The new proceeded is especially suitable for sulfur-containing heavy hydrocarbons, of which at least 90 by volume "# boil above 300 ⁰ C, for example, split gas oils, residual fuel oils, topped or reduced crude oils, crude petroleum, its lighter fractions have been removed, vacuum residues, residues from cleavage processes , oils from tar sands and oil shale. Above all, according to the invention it is possible to treat those starting substances which cannot be exposed to a strong flash effect without sulfur compounds being entrained to a large extent at the same time «

Examples of oxidizing agents which are suitable in the context of the present invention are the organic peracids, s.B. Performic or peracetic acid, or mixtures of hydrogen peroxide with formic or acetic acid, Other suitable oxidants are organic hydroperoxides,

80981 1/0967

inorganic peracids and salts thereof, aqueous hypochlorite solutions, nitrogen peroxide or air,

However, mixtures of hydrogen peroxide and formic acid are particularly suitable, since such mixtures appear to be particularly selective with regard to sulphone formation. The thermal aftertreatment of oils that have been oxidized in this way enables a significant reduction in the total sulfur content of the heavy oils _o Conditions in the oxidation stage are particularly favorable when the molar ratio of formic acid to hydrogen peroxide is lower than 4: 1 and higher than 1 : 10 and preferably has a value between 1: 1 and 1: 5 * At the higher ratios of acid to ferric oxide there is a tendency to form by-products during the thermal aftertreatment; on the other hand, at the lower ratios, the degree of desulfurization achieved is less satisfactory

The molar ratio of hydrogen peroxide used to the sulfur present is preferably selected to be greater than 1: 1, but values above 8 t 1 do not offer any increased advantages.

Mixtures of acetic acid and hydrogen peroxide are also very two-dimensional oxidizing agents

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It is often desirable to dissolve a high-viscosity, heavy hydrocarbon oil in a low-boiling organic solvent before treatment, 2, B. in benzene or carbon tetrachloride result, the viscosity wirö reduced and a more thorough oxidation scored _s so that the total amount dee remote sulfur is increased.

The thermal aftertreatment can be carried out in any manner known in the art, the temperature being selected so that the degree of thermal degradation of the hydrocarbons contained in the oil and formed by the desulfurization reaction is kept as low as possible, but is sufficient to reduce the temperature Schwefe1 break-Kohlenatoff bonds of the sulfur-containing molecules, "Ia general, temperatures above 350 ⁰ C for this 3weck sufficient, and temperatures of about ⁰ 4C0 O are particularly suitable. The thermal treatment can take place in the presence of alkaline substances such as dolomite or lime «

The sequence of the treatment stages is expedient repeated, increasing the sulfur content of the heavy oil can be further reduced "

example 1

A top residue with a sulfur content of 4.05

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1A70636

the boiled over 3 ⁷ 1 ⁰ C, and the residual fraction at dor atmospheric distillation of a Kuwait crude oil was incurred, was treated in the following manner%

75 g of the Toprückstandes were dissolved in benzene, and "" stirred at 50 ⁰ C then 28.6 cc of a 90 wt »# - formic acid and 88 cc of a 29 ijewo ^ strength Wasseretoffperoxyda exposing" The stirring was for 7 1/2 continued for 50 hours at ⁰ C and the solvent and excess reactants were removed by distillation under reduced pressure * samples of 15 g of the reaction product, each vmrden 1 1/2 hours at 30.0 ⁰ O 350 ⁰ C and 400 ⁰ O heated wherein Residue oils with a sulfur content of 3.4% by weight or 2.3% by weight, 1.9% by weight were obtained. No coke formation was observed.

This example shows that a satisfactory desulfurization eehr is achieved by using a molar ratio of acid / peroxide / sulfur such as 8-ι 8: 1 and using a temperature of 350 ⁰ C or 400 ⁰ C in the thermal after-treatment The thermal ,,! Treatment at 300 ⁰ C - although also effective to a certain extent, on the other hand, did not result in any significant reduction in the sulfur content

Example 2 In this example - the same relationships were used -

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LiOH the reaction components and the other workers' conditions as used in Example 1 ₀ B but were 200 g of the Kuwait-To priickstandes used and 113 g dee oxidized product at 400 ⁰ C thermally treated "This treatment resulted in 90 # yield to a Rücketandsöl with a sulfur content of 1.9 grains and only 0.3 Gewoji coke were formed

Example 3

100 g of the same heavy oil as used in the preceding examples, was dissolved in benzene and 6 hours com in the presence of 176 of a 29 wt _o # ~ strength by weight hydrogen peroxide and 76 g of a 90 # strength formic acid gerührto Naoh remove excess Reaction components and solvent, samples of the oxidized oil were heated ^{to 350 °} C. and 400 ^{° C. for 1 1/2 hours.} Was obtained residue sole with a Sohwefelgeha.lt of 2.74 wt "ji bewe 1.71 wt _o # · The product of the thermal post-treatment at 350 ⁰ C was npohmals one using the same quantity of hydrogen peroxide as in the first oxidation and formic acid / peroxide mole ratio of 2.0 treated After removal of the solvent, the reaction product was heated for 1 1/2 hours at 350 ⁰ C "a residue oil was obtained with a Sohwefelgehalt of 1.79 · Gew.jt Dieaee oil was again during 1 1/2 hour heated at 400 ⁰ O and so resulted in a residual oil with a 3ohulfelhalt of only 1.45

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yie ispie -l 4

In a Reihu ron Versvchen in which a hydrogen peroxide-formic acid-G-emiach ale Oxidant ₉ was used and which were carried out to determine the effect to explain the alternating peroxide ZSchwefel molar ratio, samples were the same raw material as in the previous examples had been used, heated for 6 hours in the presence of benzene with formic acid and hydrogen peroxide at an acid / peroxide molar ratio of 1 and with changing peroxide / sulfur molar ratios to 50 ° 0. ^{The products were then post-treated thermally at 400 0} C for 1 1/2 hours. The results obtained are compiled in Table I »

Table I.

MoI-
behaved-
nis
H ₂ 0 ₂ / S Thermal treatment at 400 ^° C y> Destil
lat £ Rttok-
standing oil * S
in the
Residue
oil 1
2
4th
6th
8th
12th f> coke
education 10.4
12.5
2.3
15.8
13.6
15.4 13th
69.5
76.7
65.8
66.9
65.4 3.88
3.09
2.25
1.96
1.67
1.71 2.6
2.3
3.8
5.8
5.3
5.1

BATH ORIGINAL

8098 1 1/0967

Mti to _t These results show that with a formic acid-hydrogen peroxide ι Oxydationasystem the JSolverhältnie of peroxide ssu sulfur great be less than 1 ι 1 daee no increases in action by using a molar ratio About θ: 1 are obtained,

Example 5

A series of experiments were carried out using the same starting material as in the previous examples and using a formic acid / hydrogen peroxide oxidation system in order to study the effect of varying the ratio of formic acid to peroxide in the oxidation stage on desulphurisation. All experiments were carried out using a Feroxyd / Sohwefel-Molverhältnisees of 4: 1 and carried out the oxidation itself was duroh treatment carried out the oil with the oxidizing agent for 6 hours at 50 ⁰ C in the presence of benzene the results are compiled in Table II

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Table II

1
Mole
relationship
HCOOH /
H ₂ O ₂ / S Thermal
while Treatment at 400 ^° C
111/2 hours # Back
st and s ul * s
in the
Leftovers
81 16: 4 * 1 # Koksbil
manure i> Destil
lat 70.3 2.66 8: 4: 1 2.3 18.0 70.3 2.52 4: 4: 1 4.6 13.8 76.7 2.25 2: 4: 1 3.8 2.3 74.0 2.26 1.6: 4: 1 3.8 13.7 70.8 2.20 0.8: 4: 1 2.5 14.3 88.0 1.98 0.4: 4: 1 0.4 2.5 86.3 3.84 without 5.4

The higher molar ratios of acid to peroxide favor the formation of by-products during the thermal aftertreatment, while on the other hand the ratio below 1: 5 results in unsatisfactory desulphurisation ₉

Example 6

In this example, a sample of the same Kuwait top residue as in the previous examples was used Oxidation with a formic acid / fibrous peroxide oxygenation system using a molar ratio of acid / peroxide / sulfur of 8: 4. 1 for 6 hours

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at 50 ⁰ O In the presence of benzenes 13.2 g of the reaction product were thermally treated in the presence of 2.7 g of lime for 1 1/2 hours at 400 ⁰ C * A sample of the oxidation product was treated under the same conditions with the modification, that no lime was present o The following table explains the beneficial effect that is achieved when the subsequent treatment is carried out durably in the presence of lime «,

table III

Ji Coke
education £ Destil
lat 1 » Back
stood a ul i » S im
Rttokstands-
oil With lime
Without lime ear"
4.6 1.5
13.8 94.7
70.3 2.52
2.03

Claims t

809811/0967

Claims (1)

- ¹² * U70636 Claims Process for reducing the sulfur content of a sulfur-containing heavy hydrocarbon oil, of which at least 50 VolIo ^ ^{boil over 250 0} C, characterized in that the oil is treated in a manner known per se with an oxidizing agent to form products that contain both oxygen and sulfur contain, and that these products, in particular in the form of sulphones, are at least partially decomposed by means of a thermal aftertreatment with the formation of hydrocarbons and volatile sulfur compounds _o 2ο Method according to claim 1, characterized in that at least 90 vol. # Of the treated sulfur-containing heavy hydrocarbon oil boil ^{over 300 0 C.} 5ο method according to claim 1 or 2, characterized in that that an Oemisoh of hydrogen peroxide with formic acid is used as an oxidizing agent 4ο method according to claim 3, characterized in that that the molar ratio of formic acid to hydrogen peroxide is between 1 and 4 ζ 1 and preferably between 1 and 1: 5 (ArtZHAbe, 2Nt1Saü3d§eÄnderungsees.v.4.9. 809811/0967 Process according to Claim 3 and A _9, characterized in that the molar ratio of hydrogen peroxide to the sulfur to be removed is between 1: 1 and 8 s 1 « 6ο method according to claims 1 and 2, characterized in that that a mixture of hydrogen peroxide with acetic acid is used as the oxidizing agent » ο Method according to claim 1 Ms 6, characterized in that the sulfur-containing heavy hydrocarbon oil is dissolved in a low-boiling organic solvent before the treatment » 8ο Method according to claim 1 to 7 t daduroh characterized in that the thermal treatment is carried out at temperatures above 350 ⁰ C, preferably at about 400 ⁰ C ₉ » O O (J 80S8 1 1/0967