DE1130544B - Process for the desulfurization of hydrocarbons - Google Patents

Description

GERMAN

PATENT OFFICE

D 31856 IVc / 23 b

REGISTRATION DATE: NOVEMBER 10, 1959

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: MAY 30, 1962

It is known that sulfur compounds when treated with metallic sodium or with Sodium alloys can undergo changes and also lose their sulfur. Particularly Finely dispersed sodium, which is preferred for the desulphurisation of petroleum products, is reactive has been proposed.

It is also known to use an adduct of an alkali metal for the desulfurization of petroleum products and an aromatic hydrocarbon.

For the desulfurization of hydrocarbons, one method is most advantageous, which is only removes the sulfur, but not the hydrocarbon residues of the sulfur compound. This means at the use of sodium means that the sulfur is present as sodium sulfide after the treatment should, while the hydrocarbon radicals originally bound to the sulfur in chemically modified Remain form in the main amount of the desulphurized hydrocarbon mixture. Contrary to this requirement - with the exception of hydrogenation - remove most of the today In the mineral oil technology usual desulphurization process the organic sulfur compounds as Whole, including the organic residues bound to sulfur.

The sulfur compounds found in mineral oils differ from sodium Responsiveness. Mercaptans react easily with sodium to form mercaptides. the The resulting sodium mercaptides are sparingly soluble in hydrocarbons, so that the precipitating Reaction products can be filtered off or centrifuged off. This way of working according to the German Patent specification 956 439 does not lead to a complete desulfurization, so it is the sodium treatment a sulfuric acid treatment downstream. The one remaining in the petroleum product Sulfur comes from small amounts of dissolved mercaptids. The removal of the sodium mercaptide by washing with water is not possible, since this results in a hydrolysis equilibrium Formation of sodium hydroxide and regression of mercaptan cease. The further implementation of Sodium with sodium mercaptide or the thermal treatment of the mercaptide does not lead to conversion of sulfur in sodium sulfide.

As tests have shown, mixtures of hydrocarbons and sodium mercaptides remain unchanged when heated to 260 ° C. for ten hours, even in the presence of excess sodium.

Desulfurization process of hydrocarbons

Applicant:

German gold and silver refinery

formerly Roessler, Frankfurt / M., Weißfrauenstr. 9

Dr. Georg Richard Schultze, Dr. Friedrich Boberg and Dipl.-Chem. Dr. Gerhard Menzel, Hanover, have been named as inventors

^ -

Surprisingly, it has now been found that the formation of sodium sulfide from sodium mercaptides is easily possible in the presence of organic sodium compounds. The procedure here can be to add the organosodium compound or to generate it in the reaction mixture. The easiest way to prepare the organosodium compounds in the reaction mixture is to react organic halogen compounds with sodium; aliphatic, cycloaliphatic, aromatic or mixed aliphatic-aromatic halogen compounds can be used.
The subject of a proposal that was not previously published is to use a-sodium-sodium acetate of the formula NaCH2 · COONa to remove sulfur compounds from hydrocarbons. The application of this compound is not the subject of the present invention.

The conversion of the organically bound sulfur into sodium sulfide is also with many others Sulfur compounds are not possible with sodium alone. For example, it has been found that Tetraphenylthiophene, dibenzothiophene, aliphatic disulfides, aliphatic polysulfides and aliphatic Sulphides do not or their sulfur when treated with sodium at temperatures up to 250 ° C release only incompletely as sodium sulphide. In the presence of organic sodium compounds

5.1, on the other hand, was implemented in all cases in the desired sense - d. H. Conversion of sulfur into sodium sulfide - achieved.

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This is touched up in the process according to the invention. The reaction product is worked up,

Falling sodium sulfide can be removed by centrifuging as described under a).

fuging, filtering or even - in contrast to the it will in all cases be a hundred percent

previously common technology - achieved by washing with desulfurization, while with the under a)

Remove water. After washing with water 5 and b) mentioned compounds without the addition of a

all sulfur is found as a sodium sulfide halogen compound even with longer reaction times

in the aqueous phase. times (up to 10 hours) only part of the sulfur

The process can be converted to sodium sulphide for desulphurisation of crude sulphide (in the case of

oils, of mineral oil products, coke oven products up to 20%, for those listed under b)

and synthetic hydrocarbons uses 10 substances in the best case [in the case of

will. In combination with other desulphides] up to 60%).

It is suitable for the removal of c) solutions of tetraphenylthiophene and remaining traces of sulfur. benzothiophene remain with the sole treatment. with sodium completely unchanged. When using examples _of bromobenzene or butyl bromide according to b), complete desulfurization is achieved in a heatable unit. Four-necked flask with stirrer, dropping funnel (with pressure d) In 250 ecm white spirit the following balance to the reaction flask), thermometer and sulfur compounds are dissolved in various proportions reflux condenser (closed by a drying tube), so that in all cases a. 2 ° total sulfur content of 2.7% results in: hexane

thiol, tetrahydro-thiopyran, benzyl mercaptan, hep-

1. Desulfurization using tyl disulfide, phenylethyl sulfide, tetraphenylthiophene,

organic halogen compounds thionaphthene, dibenzothiophene, thiophenol.

\ τ- * ι. ί · ι τ »ν TT 4. * ι_- ι The solution is implemented according to b). The Ver-

a) desulfurization of solutions with heptanethiol ^ ^, ^ _yon ⁸ _{Schwefd m to} kalogenverbindung

unüüexantmol. Sodium is chosen so that to 1 gram atom To 250 ecm of a solution of the mercaptan in sulfur, 1 mole of halogen compound and 3 gram of hydrocarbons (Heavy gasoline, boiling limit atoms sodium are used. 150 to 195 ° C; white oil, boiling limit 250 to 315 ° C) It is a hundred percent desulfurization with a sulfur content of 1.07% is reached at 30. The desulfurization is demonstrably not Room temperature with stirring to complete the formation when the addition of halogen compound of sodium mercaptide, there is no sufficient amount of Na-.

trium dispersion in heavy fuel or white oil. In 2. desulfurization using a

the stirred mercaptide suspension becomes so much organic sodium compound Halogen compound dropped that the molar ver 35

ratio of sulfur compound to halogenated _a ) desulfurization with phenyl sodium:

bond is 1: 1. The reaction mixture will

heated to 50 to 60 ° C and further with sodium to a 0.1 molar solution of phenyl sodium

dispersion until the molar ratio of in xylene is added while stirring 250 ecm

Halogen compound to sodium is 1: 2.2. 4 ° 0.1 molar suspension of sodium heptyl mercaptide

The mixture is then heated to 120 ° C. in xylene while stirring. The mixture changes color when heated

and maintains this temperature for another 30 minutes. At 120 ° C deep brown after 10 minutes. One stirs

Typical discolouration occurs after the reaction is down to 30 minutes at 120 ° C and continues to work

black blue on. After cooling, 1, a) is given up. The hydrocarbon phase is sulfur

for the decomposition of unreacted sodium 45 free.

Methanol to; then the mixtures are washed, V ₁ -,., π m., -. 1 ± λ- 1

with water, whereby the discoloration disappears. ^b > Desulfurization with cyclopentadienyl natnum:

The gasoline layer is after this treatment to a solution of 3.7 g of cyclopentadiene in

sulfur free. The sulfur is found in the aqueous 250 ecm heavy gasoline which is added dropwise with stirring

Phase as sodium sulfide again and can iodo- 50 room temperature containing 1.4 g of sodium

can be determined metrically. Dispersion in heavy fuel; the sodium organism

The reaction was carried out with chlorobenzene, the benzyl compound precipitates out flaky. Then 6.6 g

chloride, butyl chloride, bromobenzene, butyl bromide, hexyl mercaptan and then a further 1.4 g

and cyclohexyl bromide checked. Sodium added in disperse distribution. the

,. ",., _T. ,, 55 The mixture is heated to 120 ° C. while stirring

b) Desulfurization of solutions with n-heptyl sulfide, _{and maintains this} temperature for 30 minutes, whereby

λ ι, n-heptyl disulfide _{, the} contents of the flask turn black-brown. To

Amyl polysulfide and dimethylthiophene: _{the usual} work-up is the organic phase

To 250 ecm of a solution of the named sulfur-sulfur-free.

w ^r ^ ⁿ -n ^Ung ? ⁿ *? ^Kol Jenwasserstofifea (heavy petrol 60 3 desulphurisation of technical diesel fuel:

White oil) with a sulfur content of 1.07% ^b

one at room temperature with stirring first The diesel fuel used had the following

Bromobenzene and then the sodium dispersion. The analytical data: d _l5 0.829; Boiling curve 150 to

Ratio of sulfur compound to bromobenzene 378 ° C, S content 1.03%.

to sodium is chosen so that on 1 gram atom 05 250 ecm of diesel fuel are 2.84 g in Sulfur 1 mole of bromobenzene and 3 gram atoms of sodium dispersed in this diesel fuel Sodium come. The mixture is stirred at 120 ° C. at 120 ° C. for 30 minutes. According to the usual heated and worked up at this temperature for 30 minutes, the sulfur content is 0.79%

sunk; even with prolonged heating, the sulfur content does not decrease any further.

But if you add 4 g of bromobenzene, the diesel fuel is after the same treatment sulfur free.

Claims (3)

PATENT CLAIMS: 1. A method for the desulfurization of hydrocarbons, characterized in that sulfur-containing hydrocarbons with an organosodium (ie containing the C-Na bond) compound, the a-sodium sodium acetate (NaCH ₂ · COONa) is excluded, or an organosodium compound and Sodium treated. 2. The method according to claim 1, characterized in that the organic sodium to be used Compound in the reaction mixture of organic halogen compound and sodium is formed. 3. The method according to claim 1, characterized in that the organic sodium to be used Compound in the reaction mixture of a substance with active hydrogen and Sodium is formed. Considered publications:
U.S. Patent No. 2,048,169. Legacy Patents Considered:
German Patent No. 1 071 260. © 20 »607/329 · 5.62