DE1545238A1 - Process for the complete or partial removal of straight-chain hydrocarbon compounds from hydrocarbon mixtures - Google Patents

Description

Dr. Expl.

PATENT LAWYERS

DR-ING. BY KREISLER DR.-ING. SCHÖNWALD 1545238 DR.-ING. TH. MEYER DR. FUES

KÖLNLDEICHMANNHAUS

Cologne, December 7th, 1965

Fu / Ax

The British Petroleum Company Limited, '

Britannic House, Finabury Circus, London, E. 0 * 2 (England).

Procedure for the total or partial removal of straight-chain hydrocarbon compounds from hydrocarbons st off mix

(Separation registration III)

(Removal from patent (patent application

B 7V851 IVa / 6a))

The invention relates to a method of manufacture of microorganisms, e.g. yeast, in particular to a process for the complete or partial removal of straight-chain Hydrocarbons from mixtures with other hydrocarbons.

Certain petroleum fractions, especially gas oils, are known to contain mainly straight-chain hydrocarbons Paraffins, which are waxes and have a detrimental effect on the * Affect the pour point of the fraction. In other words, if all or part of these hydrocarbons are removed, the pour point of the fraction is lowered. The wax is usually removed by precipitation with the aid of solvents. The wax originally present in the fraction is used as such, ie. without conversion into more valuable ones Products won »

The petroleum fractions that boil under gas oils, e.g. heavy naphthenes and kerosene, also contain straight-chain ones Hydrocarbons that are potentially valuable for conversion in other products, but so far the

90983 1/1280

The use of these hydrocarbons is made more difficult by the fact that they have to be separated from the petroleum fractions in which they are contained "before they can be converted into other products _{or the like}

In a process in which a microorganism is fully or partial removal of straight-chain hydrocarbons from hydrocarbon mixtures is used, it was found that in this process in general by-products, containing carbon, hydrogen and oxygen, e.g. esters, are formed. These by-products can remain in the hydrocarbon fraction separated from the microorganism and present impurities In particular, in cases where a waxy gas oil is used as the feedstock, the recovered gas oil have too high a cloud point as a result of the presence of these by-products.

According to the invention it has been found that these by-products are at least partially reduced by a hydrogenation process adverse products can be converted. The invention accordingly provides a method for complete or partial separation of straight-chain hydrocarbons from mixtures with other hydrocarbons, which thereby is characterized in that a microorganism in the presence of a hydrocarbon feed that consists of a Mixture of straight-chain hydrocarbons with other hydrocarbons consists in the presence of an aqueous one Nutrient medium and a gas containing free oxygen cultivates, then separates the microorganism from the remaining hydrocarbon and the remaining hydrocarbon subjected to hydrogenation. Petroleum fractions are preferably used as the filler material.

The method according to the invention is particularly valuable for the treatment of gas oil fractions from petroleum, the straight-chain Contain hydrocarbons in the form of waxes because

909831/1280

by the method according to the invention a gas oil with improved Pour point is obtained while the waxes are being converted into a valuable product.

The straight chain hydrocarbons are usually in the Inlay materials used according to the invention as paraffins available. They can, however, also be present as olefins. Furthermore, mixtures can be used, the straight-chain Contains paraffins and olefins.

It is an important feature of the invention that in the Cultivation of yeast in the presence of those described above Input materials under conditions which favor the yeast growth at the expense of the straight-chain hydrocarbons, the other hydrocarbons, e.g. isopsraffins, naphthenes and aromatics, are not broken down or you split share is very small at best · Furthermore In contrast to the usual chemical processes, which obey the law of mass action, the speed of removal of straight-chain hydrocarbons with a decreasing proportion of these hydrocarbons in the overall mixture of hydrocarbons is not significantly lower (except of course in the last phases of the removal). So can, if desired, the achieved percentage conversion of straight chain hydrocarbons is maintained at a value approaching 100 without a disproportionately large amount of contact time is required to low Achieve improvements. Furthermore, this high conversion can be achieved in a continuous process without the Use a long reaction path to help.

By using this procedure under conditions similar to the To limit splitting of the straight-chain hydrocarbons, it is possible; to work so that only a desired part this hydrocarbons is removed.

Suitable feedstocks for the process according to the invention are kerosene, gas oils and lubricating oils _or these

909831/128 0

Feedstocks can be unrefined or have undergone some refining treatment, however, they must contain straight chain hydrocarbons to be useful for the purposes of the invention. Suitably, the content of straight-chain hydrocarbons is petroleum fraction 3-45 wt _e - $.

The microorganisms that are cultivated according to the invention are yeast, fungi or bacteria.

If you are using yeast, it will preferably be part of the family Cryptoooccaccae, especially to the subfamily Cryptoccooooidae. If necessary, however, asp / osporogene, for example Yeasts of the Saccharomyoeloidae subfamily can be used. The preferred genera of the subfamily Oryptoccocooidae are Torulopsis (also known as Torulä) and Candida. The preferred yeast strains are listed below. The strains whose deposit numbers are mentioned in the table below which are particularly preferred are those for Designation of strains that are available from the Centraal Bureau vor Schimmelculture, Baarn, Holland.

Candida lipolytica

Candida pulcherrima CBS 610

Candida. utilis

Candida utilis, Variati major CBS 841

Candida tropicalis CBS 2317

Torulopsis collisculosa CBS 133

Hansenula anomala CBS 110

Oidium lactis

Neurospora sitophila

Of the above-mentioned strains, Candida lipolytica is particularly preferred.

Bacteria can also be used as microorganisms «, expedient the order Psaudpmonales, Eubacteriales and Actinomycetales used. Preferably

9 0.9 831/1280

bacteria used are the families Bacillaceae and Pseudomonadaceae. Preferred species are Bacillus megatherium, Bacillus subtilis and Pseudomonas aeruginosa. Other suitable strains are:

Bacillus amylebacter.

Pseudomonas natriegens

Arthrobacter sp _e

Micorooceus sp.

Corynebacterium michiganense

Pseudomonas syringae

Xanthomonaa begoniae

Flavobacterium ap * devorans

Aeetobacter sp _c

Actinomyces sp.

Agrobacterium sp _e

Aplanobacter sp _o

Of the mushrooms come those of the Aspergillaceae family in question, a suitable genus is Penieillium. Preferably Penieillium expansum is used. As another usable Genus Aspergillus comes into coinage.

The cultivation is usually carried out in an aqueous nutrient medium carried out. If necessary, also know certain solid drilling media be used. In both cases, a gas containing free oxygen must be supplied. Penieillium expansum is suitable for cultivation in an aqueous growing medium, that contains hydrocarbons. Penieillium roq.ueforti, Penieillium notatum, Aspergillus fussigatus, Aspergillus Niger and Aspergillus versicolor can be on a solid Cultured medium containing hydrocarbons.

In addition to the input material, the growth of the microorganisms an aqueous nutrient medium and an oxygen source, preferably in the form of air. A typical nutrient for growing Nocardia has the following composition ί

9098 3 1 / 1.28 0

- 6 - Ammonium sulfate 1 g 1545238 Magnesium sulfate 0.20 g Bis (II) sulfate heptahydrate .0.005g Manganese sulfate monohydrate 0.002g Monopotassium phosphate 2 g Disodium phosphate 3 g Calcium chloride 0.1 g sodium 0.1 g Yeast extract 0.008g

Distilled water (to make up to 1000 ml).

For other bacteria, a growing medium of the following is suitable Composition:

Monopotassium phosphate 7 g

Magnesium sulfate heptahydrate 0.2 g

iSodium chloride 0.1 g

Ammonium chloride 2.5 g

Tap water (trace elements) 100 ml

Yeast extract 0.025 g

Distilled water (to make up to 1000 ml)

A suitable nutrient medium for yeast (and fungi) has the following Composition:.

Diammonium phosphate 2g

SLium chloride, 1.15. G

Magnesium sulfate heptahydrate 0.65 g

Zinc sulate 0.17 g

Manganese sulfate monohydrate 0.045 g

Bisen (H) -S ¹ UIfatheptahydrate 0.068 g

Tap water 200 g

Yeast extract 0.025 g

Distilled water (to make up to 1000 ml)

909831/1280

Microorganisms, especially yeast, sometimes have difficulty growing when first using Grown hydrocarbon fractions as feedstock will. Sometimes it is necessary to use a microorganism for inoculation which has previously been used to grow on the hydrocarbon fraction to be used has been adjusted is. It is also possible that the microorganisms in spite of the cultivation in the presence of an aqueous mineral Medium containing the appropriate nutrients grow with difficulty because the hydrocarbon fraction does not contain the growth factors found in carbohydrate feedstocks unless these growth factors are added.

The growth of the microorganisms used is favored, if you add a very small amount of a yeast extract to the culture medium (an industrial product rich in group B vitamins obtained by the hydrolysis of yeast) or in general to vitamins of group B and / or biotin. This amount is preferably on the order of 25 parts per million, based on the aqueous fermentation medium. It can be higher or lower depending on the incubation chosen conditions.

The growth of the microorganism takes place at the expense of the input fraction with intermediate formation of bodies - mainly Fatty acids - with an acid function, so that the p "value of the aqueous mineral medium decreases progressively. Without correction, growth comes to a standstill, fairly, quickly, and the concentration of the microorganism in the medium or the cell density no longer increases, so that a so-called stationary Phase is reached.

The aqueous medium is therefore preferably kept at the desired p ^ value by gradually or continuously adding an aqueous medium with a high p n value. Usually, the p _H value of ~ Rährmediums with the use of fungi, or is

909831/1280

Yeasts, particularly when using Candida lipolytica, in the range of 3-6, preferably 4-5, held (bacteria require a higher _H p ~ value of usually 6.5-8.) Suitable alkaline materials for the addition to the wort are Sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate and ammonia in free form or in aqueous solution.

The optimum temperature of the culture medium differs according to the A _r t of yeast used, and is usually in the range of 25-35 ⁰ C. When using Candida lipolytica, a temperature range of 28-32 ⁰ C preferred.

The uptake of oxygen is essential for yeast to grow. The oxygen is usually supplied as' air. In order to keep the growth rate high, the air supplying the oxygen must be stirred into fine bubbles be divided. The air can be introduced through a pritte, but what is known as "vortex aeration" can also be used Ventilation system should be applied.

It has been found that using yeast of the strain Candida lipolytica in a method according to the invention in which the aeration is carried out by "vortex aeration" high growth rate is achieved, the generation time in the range of 2-5 hours «, and the cell concentrations * · tration is increased by a factor of up to 12 in 2 days.

In batch operation, the microorganisms initially grow with them slow increase in cell density. (This growth period is hereinafter referred to as the "inertia phase".) Thereafter the growth rate increases to a higher value. The period with the higher growth rate is called "Exponential phase" means »Then the cell density constant again (the "stationary phase"). A certain amount of the microorganism for the start of the next batch is preferably taken before the exponential phase ends. Incubation is usually done before stationary • Phase canceled. In this phase the microorganism becomes

9 0 9 8 3 1/12 8 0

usually, from the bulk of the aqueous milling medium and separated from the main mass of the unused input fractions

Optionally, the microorganism can before the other Cleaning of the product can be subjected to autolysis.

After one of the work-up methods for the product, the greater part of the closed aqueous phase is first separated off. This is preferably done by centrifuging or decanting. The separated aqueous phase usually contains a higher one Concentration of ions that are not nutrients than can be tolerated in the circulatory stream. If this is the pail only part of the recovered aqueous phase can be recycled. For example, it is common possible, about 96% by weight of the aqueous present in the product Phase to be separated, of which (on the same basis) about 20 wt .- # are discarded Amounts of the necessary nutrients fed to what it is returned to the fermenter. Optionally, the supplementary nutrients can be fed to the fermenter as a separate stream are fed.

When applied to the cultivation of yeast, the method can comprise the following product separation steps. In certain In addition to yeast, other microorganisms can also be separated in this way.

By centrifuging the product from the fermenter, three fractions are obtained, in increasing order Density;

I) an oil phase containing yeast cells,

II) an aqueous phase containing traces of oil and yeast, and ΠΙ) a "yeast cream" made from yeast, on whose cells a certain amount of Amount of oil is bound, together with the aqueous phase, consists"

9 0983 1/12 8 nights

After fraction II is won, fraction III or a mixture of fractions I and III mixed with an aqueous solution of a surfactant. This treatment -has the purpose of removing the oil, which is apparently retained on the cells by adsorption, from the yeast cells to separate.

It may be advantageous to use an edible surfactant, e.g. a sugar ester, which enables the effort for the subsequent washing, which is necessary to remove an inedible surface-active from the yeast To remove funds, to decrease.

The emulsion thus formed is broken by centrifugation to obtain three fractions: -

IV) an oil phase,

V) an aqueous phase containing the surfactant, which is used for treating fractions I) and III) in the Cycle is performed, and

VI) a "yeast cream" which consists of yeast that is still with oil is contaminated along with an aqueous phase of the surfactant.

TJm the consumption of surface-active agent possible low To keep, the aqueous washing solution containing the agent is circulated.

Fraction VI can be washed alternately with surfactants Means and centrifugation are further worked up until the oil content of the yeast is a desired low Has reached value. The yeast cream, now consisting of yeast and aqueous surfactant, can do well with Water washed and centrifuged again. If necessary, this yeast cream can be washed twice or more will. If desired, one or more of these can be washed with? / Water (but preferably not for the last) salt water (e.g. sea water) can be used. The final wash is preferably done with soft water.

939831 / 128Ü

To meet the need for soft water that is required for the process is to be kept as low as possible, all the water from the last wash is used; A part serves as make-up water for the nutrient medium in which fermentation takes place, part - if necessary - as make-up water for the solution of the surface-active agent, and the remainder is added to the salt water used for washing in order to reduce its salt concentration «, Finally the yeast can be dried under conditions that for later use as driving and animal feed suitable.

The hydrocarbon obtained, which has not been split, is subjected to hydrogenation with or without an inserted refining stage. Suitable catalysts for the hydrogenation are compounds of cobalt and molybdenum with or without iron, winding, Mckel / tungsten sulfide or any other conventional hydrogenation or desulfurization catalysts. The hydrogenation is preferably carried out under the following conditions! Depending on the catalyst, the temperature can be in the range from 100 to 500 ⁰ G, the pressure between 10 and 70 kg / cm, the space flow rate between 1-10 V / V / hour. and the hydrogen / hydrocarbon ratio is in the range from 0.1: 1 to 5: 1 »The hydrogenation can be carried out in the liquid phase, gas phase or mixed phase. ■

Actions that can be taken to keep a purified one Microorganism or a product derived therefrom or the process with regard to the manufacture of the not to improve the split hydrocarbon fraction are in the patents and patent applications listed below described. These measures can be used within the scope of the invention with the method described here will")

BAD OBtGJNAL

909831/128 0

Preferred methods used in the cultivation of the microorganisms and in the production of the product are described in the following patents or patent applications: British Patent 91 ² I-567

German patents (patent application B 74851 IVa /

6a), (patent application B 79321 IVa / 6b) and

....... (patent application B 79322 IVa / 6b).

Baltic patent applications

44606/62 49069/62 45005/63

46906/62 1168/63 45006/63

49051/62 2234/63 45007/63

49053/62 21253/63. 45008/63

49054/62 21668/63 45010/63

49058/62 25210/63 45011/63

49059/62 44998/63 45012/63

49060/62 45001/63 45013/63

49063/63 45002/63 45014/63

49068/62 45003/63

In the following examples the cell weight is expressed as dry weight of yeast per liter of culture medium.

example 1

40 l of an aqueous mineral Uährmediums of the following composition are filled into a. Fermenter made of stainless steel, which has a capacity of 60. TJM to maintain the temperature in the fermenter constant at 3O ⁰ O 'water was circulated in a Eingraum, which was formed by the Haum between two concentric cylinders of which represented the smaller the fermenter itself. The aqueous nutrient medium had the following composition

Diammonium phosphate 2g

Potassium hydrogenate 1.15 g

Magnesium sulfate heptahydrate O ₉ 65 g

909831/128 0

- 13 - Zinc sulfate 0.17 G 1545238 Manganese sulfate monohydrate 0.045 G Iron (II) sulfate heptahydrate 0.068 ■ g Yeast extract 0.025 G tap water 200 Distilled water (to fill up to 1000 ml)

20 l of an inoculum from a 24-hour culture of Candida lipolytiea on a mixture of Oq-O ^ g-KooBUfal paraffins were then added so that the cell density was about 1 g / l heavy gas oil (15 g / 1 of the fermenter) introduced. This amount was sufficient to bring the cell density to 2 g / l. The culture temperature was maintained at 30 + 1 ⁰ G, the p _H value at the fourth Aeration and agitation were made to deliver 3 millimoles of oxygen / L medium / ton.

Using an automatic Pg control system, aqueous 1On ammonia introduced. After the addition of ammonia reached 20 ml, the intermittent addition of Gas oil started in an amount determined by the theoretical needs of the culture, assuming a yield of

mn γ dry weight of the yeast formed _ _{in <J} / ^{ιυυ x} required gas oil "* ^IU > *

and a cell division time of 3 hours was determined. These The addition took place every hour until the total amount of gas oil added 250 g / l, i.e. a total of 17 l.

Starting from a cell density of 2 g / l it was after 25 hours (at the end of the exponential growth phase) a cell density of 18 g / l reached «

Key figures of the heavy gas oil used

Density 15 ° 0/4 ° 0 0.876

Flash point, Afnor above 12O ⁰ O

90983 1 / 128U

Cloud point + 2O ⁰ C

Pour point + 18 ° C

Normal paraffins 10

Saybolt distillation

Initial boiling point 221 ⁰ C

228 ⁰ C 363 ⁰ C 402 ° C end of boiling above 405 ⁰ C

Backlog 1 VoI ₀ - ^

Loss O VoI "- $

After 25 hours, part of the culture was removed from the fermenter. For this part of 300 ml of non-delaminated gas oil were obtained by centrifugation at +5 ^0C. The remaining gas oil had the following key figures:

Density 15 ° C / 4 ° C 0.890

Flash point genuAfnor over 120 (J Cloud point + 5 ° C

Pour point -13 ⁰ C

η-paraffins' 2.1 wt .- ^

Saybolt distillation

Initial boiling point 248 ⁰ C

$ 5 300 ⁰ C

50 ^ 368 ⁰ C

$ 10 381 ⁰ C

395 ° C 402 ⁰ C end of boiling '" above 405 ⁰ C

Backlog 1 VoI - #

Loss 0

The gas oil obtained was washed with water and with phosphorus pentoxide dried. It was then in a lot of

90 9 831/1280

400 ml / hour at 39O ⁰ C and a pressure of 70 kg with hydrogen in an amount of 100 ml / hour passed over 100 ml of a customary Oo / ko hydrogenation catalyst. After this treatment, the gas oil showed a cloud point of -TO C.

Example 2

The culture was continuously fed in an amount of 300 ml / hour. with a medium containing 10 wt _e -? i contained heavy gas oil, a mineral medium of the composition described in Example 1 was emulsified in 90 S, introduced into a fermenter 1-5, contained the 3 1 culture?. The gas oil used had the following key figures

Density at 15 ° A ° ^G ° » ⁸ 't5

Pour point + 17 ° 0

Cloud point + 20 ⁰ O sulfur 1 »6 wt» -? I

n-paraffins 12 wt .- ^

Flash point according to Afnor 135 ⁰ C

Saybolt distillation: ⁰ O.

Start of boiling. 139

$ 5 304

362 398

End of boiling over 400

Backlog T ToI. -fi

Loss ■ 0 vol.-ji

The p n value was kept at 4 1 0.1 by the automatic addition of 10N ammonia using a suitable apparatus. The temperature was kept at 30 ⁰ O. The agitation and aeration were made to deliver 3 millimoles of oxygen / L of medium / lain.

The cell density became after a few days with a value of 10 + 1g dry matter / l constant «Then it became such

90S831 / 1280

Amount of culture withdrawn that by centrifugation at 5 ° C ml of non-split gas oil were obtained The remaining gas oil had the following key figures:

Density 15 ⁰ A ⁰ C 0.888

Flow point -5 ⁰ O

Cloud point +21 ⁰ C

Tal sulfur 1.95 percent by _# - i

n-paraffins 2.1 wt. -i "

Flash point according to Afnor 150 ⁰ C

Saybolt distillation: ⁰ ° C

Beginning of boiling 265

55 * 310

50? $ 365

95 # 398

End of boiling over 400

Residue 1 vol - ^

Loss 0 vol-ji

This non-split gas oil was based on that in Example 1

Hydrogenated manner described «The cloud point was lowered ^{from +21 to 0 G.}

909831/1 2 8 (J.

Claims (1)

15Α5 "23 ~ δ Claims. Process for removing low-chain hydrocarbons from their mixtures with other hydrocarbon compounds by cultivating macro-. Organisms in the presence of an aqueous culture medium on the mixture of hydrocarbon compounds in the presence of a gas containing free oxygen, characterized in that, following the growth stage and after separation of the remaining. Hydrocarbon fraction these subjected to a hydrogenation treatment ". '■' ■■ "2, method according to claim 1, characterized in that a waxy gas sol is subjected to the process and the treated gas oil then becomes a product is hydrogenated with a reduced cloud point. 3 · A process according to claims 1 and 2, characterized - in that the hydrogenation in the presence of cobalt and KcIytdUn containing catalysts .vorzugsweise in the temperature range of 100 to ⁰ 5 CO CjUnU pressures ranging from 10 to 70 kg / cm ^{2 is} carried out. ² K The method of claims 1 to '3, characterized in that is carried out in the hydrogenation with hydrogen / carbon nwa.s se rstcffverhältnissen in Eereich of 0.1 / 1 to 5 / I, wherein space velocities in the range of 1 to 10- V / V / hour are preferred. '.. 5- Process according to claims 1 to K ₃ -Jad-urch characterized ,, that microorganisms yeast or bacterial strains are used ORIGINAL BATH 909831/12 80