DE2244895C3 - Process for the catalytic oxidation of lupulones to hulupons - Google Patents

Description

resins, which fall however brewing technically recyclable 45 ^{do? n} . _{Invention it is} therefore that normally

are. Although they have the chemical structure of the humulo- J ^ J ^ SltS ^ especially those,

nen are very similar, they can be used in the convection η cht »JJ ^ P ^^ _{in the humulon-} free

Brewing methods are not exploited, as they are in beer ^ ^bel '« ^r f * °°". " _F simpler way in

are practically insoluble, do not taste bitter and have a »" «^, gggi ™ hnT bkter-tasting

also cannot be isomerized. They are therefore ₅ o «« SuL convict. The won

eliminated and discarded. = * on π g satisfactory purity and cheap

also called "base extract" or "Basex", contains isohumulone is possible

of

³ 4

To deliver a pH value of Π 'to 14, at 0 to 90 ⁰ C, by means of consumption of the reaction, the alkali

Oxygen or oxygen-containing gases in the presence of a concentration are not critical - as later

! “It is a catalyst that is characterized by the fact that it is carried out - but takes place at concentrations

^ Finely divided noble metals as a catalyst or alkali degradation normally occurs over 10 times. It will therefore

Transition metals of 1 and 7 Nb K

^ ₁₁₁ as y all or e

(fcyde of transition metals of the 1 and 7 minor 5 concentrations of 0.1 to 0.5 normal preferred, ^ ppe as well as bismuth or cobalt oxide or mixtures The alkalinity of the medium can also with organic safe oxides or their ions or mixtures thereof, bases The reaction, for example, takes place if applied to supports, used and quite well with triethylamine. It is therefore only essential that the lupulate anion is present and that the medium conducts it with an alkali concentration of at most 10n is sufficiently alkaline.

The reaction is exothermic, so that - starting from

Precious metals, and oxides of the first and seventh of a reaction mixture of normal room subgroup as well as bismuth and cobalt, said temperature-usually a reaction temperature! Lobaltoxyd, bismuth oxide, manganese oxide and copper receives from about 40 to 60 ⁰ C, depending on the concentration _m a and mixtures of these oxides, especially 15 and the amount of the batch, that is to say the ratio of the produced, are preferred. The catalysts can convert basic heat to dissipated heat. You can be used up to, Burz without a carrier, if they work at the boiling point of the reaction medium , and in a technically suitable form, z. B. even under pressure, but this is not preferred for practical ds sponge or sufficiently large-pored sintering reasons. Above 100 ⁰ C become material. All the usual catalyst supports are suitable, however, as many, for the most part, polymeric oxide supports, provided they are sufficiently alkali-resistant. products are formed that the yield drops sharply. Particularly suitable are kieselguhr, activated carbon, calcium, reaction ^{temperatures of 0 to 90 0} C are therefore phosphate, magnesium oxide or calcium carbonate, and as mentioned above - for practical reasons - dolomite and clay, while z B. silica gel and temperatures of in particular 40 to 60 ° C used, alkali-soluble aluminum oxide for practical reasons. Like stork acidic cation auros, alkali degradation does not yet begin, which at higher polystyrene-based exchangers could be very good as easy filtering temperatures, especially with higher alkaline carriers. In principle, all cation concentrations are suitable. One exchangers, but they are from the company colors Bayer 30 sufficiently high reaction speed is already AG in the last years Ren developed, highly abrasion-available at 0 ° C.

solid cation exchangers are particularly well suited, the reaction rate is directly dependent

as normal exchangers under the given reaction from the partial pressure of oxygen, so that a Drucktionsbedingungen suffer a significant amount of abrasion increase basically accelerates the reaction, can (see Bayer company pamphlet, No. 1 1412). 35 For practical reasons, one works appropriately

It is also possible in a completely homogeneous under normal pressure with oxygen (bomb oxygen). Solution to work, with the catalyst in the form of air, the process goes very well, but if a soluble, stable in the alkaline range occurs because of the larger amounts to be enforced, a complex salt must be present. As a soluble catalyst, undesirable foaming.
Sator for a homogeneous reaction is z. B. Cobalt- 40 When the known methods were checked, salcomine in methanol was suitable. found that the well-known auto-oxidation of

The substrate of oxidation is the lupulate anion. Lupulones in organic solvents are therefore suitable for the reaction, temperature increase can be accelerated, in which lupulas are soluble, especially water, but the yield of Hulupon does not increase above 15% methanol and other lower alcohols, but can also be 45. In the non-polar solvent there is glycol, acetone, acetonitrile or sulfolane and presumably a destabilization of the polar supermixtures thereof. In principle, all transition states taking place with many side reactions are suitable, polar solvents. It has been shown that the organic non-polar solvents are therefore not usable, the better, the greater the di-
is the constant of electricity. 50 The oxidation of lupulone without a catalyst

Of the solvents, water produced in one's own work in alkaline, polar ones is naturally preferred. In order to obtain higher concentrations, although atm solutions by increasing the pressure to 60 and imReaktionsmediumwirdhäufigeinWasser-methanol increase in temperature uses a Wesent mixture to about 100 ⁰ C, since there the solubility of the Liehe acceleration of the oxidation, but is better due to the starting materials. One works in the uncontrolled reaction only a yield of solution, this term, however, suspensions about 20% Hulupon. In the course of this work includes. The lupulone to be converted actually shows a surprising acceleration of the - if the concentration is too high for the full solubility reaction rate and a substantial amount - is gradually converted into solution and is thus converted into an increase in yield through the addition of black metal, while impurities remain undissolved 60 catalysts on diatomite or activated carbon as and therefore relatively easy to separate carriers,
be able. Show noble metals on carriers as catalysts

The reaction under alkaline conditions besides its long life, insensitivity expediently at a pH value of at least 10, against poisons and easy removability from the better 11 to 14, in particular 13 to 14, carried out. 65 reaction medium has the main advantage that it The alkali concentration is between below 0.1 do not contaminate the reaction product in any way, normal to 10 normal. As long as the solution is sufficient.

is alkaline to lupulate anions and the alkali that also oxide catalysts and mixed catalysts

Under the aforementioned conditions, this must be dissolved in beer. D.e improved loosening

Process for a continuous process management thus enables the combination with iso-

particularly suitable. A great advantage is that you can use humulone supplements. Therefore it is used

work in purely aqueous, methanol-free media i. of potassium salts versus sodium salts in the

can. Production of humulone is particularly preferred. Through

Preferred catalysts are black metal- addition of a solubilizer such as 1,2-propylene-

catalysts, e.g. B. platinum, palladium or rhodium glycol, the solubility is improved.

on activated carbon or kieselguhr. The following examples illustrate the invention.

suitable are the metal oxides of manganese, copper, 15

Bismuth and cobalt and mixtures thereof on bis ο ie 1 1
Carrier materials.

Both the reaction speed and the. <- ",» "· _, ...

Yield strongly depend on the type of catalyst 8 g of lupulone were dissolved in 50 ml of methanol, with

away. For example, cobalt oxide 10% on kieselguhr 20 shows 3 ml of 10 n sodium hydroxide added and stored in a laboratory

and platinum on activated carbon the highest reaction autoclave of 120 ml content was then filtered

speeds, while bismuth oxide 10% on 100 mg 10% platinum on activated carbon (Engelhardt-

Diatomaceous earth leads to the purest products. As the catalysts) were added, the autoclave was closed

Differences in purity are usually not very great, and a pressure of 40 atmospheres oxygen is pressed out. the

the fastest reacting catalyst in the general autoclave was placed in a water bath and turned on

mine preferred. 50 ° C heated. Then the dysentery was employed

The dependence on the amount of catalyst and the oxygen uptake on the basis of the pressure is below the saturation limit linear. Loss is being prosecuted about it. After 30 minutes the reaction was over the rate of response regardless of before ended. The autoclave was cooled down, depressurized amount. This point is again of the type of 30 loads and the catalyst is filtered off. The solution Catalyst dependent and is z. B. with 10% silver was then mixed with the same amount of water, on activated charcoal at less than 10 mole percent, acidified and extra-related twice with 100 ml of η-hexane each time on lupulate, while at 10% hate. The combined hexane solutions were over Cobalt oxide dried on kieselguhr and, in the case of platinum, on active sodium sulphate and evaporated. It's chalking up the saturation limit is much higher. 6.4 g of brownish oil with a Hulupon content remained

In detail one proceeds as follows: One of 44%.

dissolves lupulone with a desired amount of alkali. For comparison, the same approach was carried out without a catalyst

(e.g. potassium hydroxide solution or sodium hydroxide solution) carried out in the desired generator. The theoretical amount of oxygen

Solvent or extracted the lupulone-containing was not yet after a reaction time of 12 hours

organic solution with alkali, heated to a 4 ° reached. The Hulupon yield was 14.2%.
selected temperature, adds the catalyst and
oxidizes by mixing in oxygen or air.

The reaction is calculated after the inclusion of Example 2
Amount of oxygen or a given or

experimentally determined excess canceled, 45 20 g Basex extract with a lupulone content of 7 g

by introducing gas or stopping stirring. were dissolved in 150 ml of hexane and filtered. the

The catalyst is then filtered off, the clear solution was with a mixture of 50 ml

The filtrate is acidified to a pH value of 1 and methanol, 25 ml of water and 4 ml of 10 N sodium hydroxide solution

extracted completely with hexane. Shaken out of the hexane. The aqueous methanol phase was

solution can be added to the laboratory autoclave by extraction with aqueous 50, with 100 mg catalyst

Potash lye, possibly with the addition of propylene glycol with 10% platinum on activated carbon (Engelhardt)

up to a pH value of 5 to 8 potassium hulupat and treated as in example 1. The reaction was

Obtain solutions of high purity that end in water after 60 minutes. The titrimetric Hulupon

or beer are completely soluble. True, as with the yield was 47%.

all beer bitter substances are also soluble at Hulupon
speed in beer is completely sufficient, since only 10 to 50 ppm

needed for bitterness. For the practical example 3
Handling when adding to beer are however higher

concentrated solutions required, which were a good 4 g of lupulone in 100 ml of 0.5 N sodium hydroxide solution Enable distribution and rapid dissolution. Ge 60 dissolved with stirring, in a 250 ml three-necked flask suitable for this are the salts, which (analogous to isohumu with gas inlet pipe, reflux condenser and inner ion) a thermometer nitrated in water or in propylene glycol / water and treated with 1 g of catalyst (see Table essential have higher solubility. There are belle) irritated. After purging with oxygen, the significant differences in solubility between apparatus heated to the given temperature. K and Na salts, as potassium hulupat z. B. up to 65 Then, while stirring vigorously with a 100 g / l is soluble in water, while sodium hulupat magnetic stirrer and passing oxygen through the is only soluble to less than 40 g / l. Hulupon itself is oxidized lupulate solution. After the reaction has ended, only about 1.1 to 1.6 g / l soluble. The potassium salt of the can be identified by the clear decrease in oxygen uptake.

or after 250 ml of oxygen had been consumed, the stirrer was switched off. The solution was allowed to cool, the catalyst was filtered off over a frit, the solution was acidified with 2 nH _a SO ₄ to a pH of 1 and extracted twice with 50 ml of n-hexane each time. The combined hexane solutions were dried over sodium sulfate and evaporated. The Hulupon was obtained in the form of a bright yellow to brownish yellow oil. The yields can be seen from the table.

Example 3a

The same batch with 200 mg of cobalt chloride unsupported was ended after 20 minutes. yield 38% Hulupon. With 200 mg of copper nitrate, a yield of 37.2% was obtained in 35 minutes.

The same approach with 1 g of pure carrier material (MgO) in place of catalyst exhibited only an oxygen uptake of 49 mL at 5O ⁰ C after 170 minutes.

catalyst

carrier

Temperature reaction time yield ⁰ C min.%

Kieselguhr

100 mg platinum 10%

100 mg palladium 5%

100 mg rhodium 5% (Engelhardt)

100 mg gold 5%

100 mg silver 10%

100 mg platinum 5%

Manganese oxide 10% Copper oxide 10% Cobalt oxide 10%

Bismuth 10%

Copper oxide 0.5% + manganese oxide 9.5% Manganese oxide 5% + copper oxide 3%

+ Cobalt oxide 1.5% + silver oxide 0.5%

Cobalt oxide 10% + bismuth oxide 1% Cobalt oxide 10% + bismuth oxide 1% Cobalt oxide 10% + bismuth oxide 1% Cobalt oxide 10% + bismuth oxide 1% Cobalt oxide 10% + bismuth oxide 1% Cobalt oxide 10% Cobalt oxide 10% Cobalt oxide 10%

Cobalt oxide 10% Cobalt oxide 10%

Example 5

20 g of Basex (lupulone content 7 g) were dissolved in 150 ml of hexane and extracted with 150 ml of 0.5 η sodium hydroxide solution. The aqueous phase was heated ^{to 80 ° C. in a reaction flask filled with 10% platinum on activated carbon (Engelhardt)} and gassed with oxygen. The reaction was over after 48 minutes. The catalyst was filtered off and, after acidification, the aqueous phase was extracted twice with 100 ml of hexane each time. After drying over sodium sulfate and evaporation of the hexane, 8.2 g of brown oil remained. The Hulupon yield was 44.5%.

Example 6

4 kg of Basex (lupulone content 35.2%) are used in 401 Dissolved hexane. After filtering off a little insoluble precipitate, this solution is transferred to an extractor extracted with 601 0.4 η sodium hydroxide solution

Activated carbon 88 24 42 Activated carbon 50 90 34 Activated carbon 50 122 40 Kieselguhr 50 90 34 Activated carbon 50 70 27 Kieselguhr 50 15th 51 Kieselguhr 88 46 42 Kieselguhr 88 20th 41 Kieselguhr 88 12th 41 Kieselguhr 88 47 50

89

48

Kieselguhr 80 Kieselguhr 88 Kieselguhr 75 Kieselguhr 65 Kieselguhr 40 Kieselguhr 0 Magnesia 50 Calcium phosphate 50 Cation exchanger 50 based on polystyrene volume 50 pure silica gel without 50 additions

25th 43 6th 46 ₅ so 48 4th 48 12 * ° 47 19th 47 12th 49 10 39 65 39 11th 47 6th 47

a clear reddish-brown aqueous phase as the lower phase and a brown, dark hexane phase

so green precipitate as the upper phase. The upper phase is evaporated to recover the hexane The lower phase is mixed with 400 g of catalyst (10% cobalt oxide - 1% bismuth oxide on kieselguhr) and placed in a 120-1 stirred tank with aeration turbine filled. The vessel is closed, evacuated and a pressure of 2 atmospheres oxygen is injected. It is ^{then preheated to 30 °} C. from the outside. The turbine is then switched on. The temperature rises very quickly from 30 to over 40 ° C, the pressure drops rapidly to 0.5 atm. The reaction has ended after 5 minutes

The excess gas is left centrifuged off the catalyst in a clarifying centrifuge. The aqueous phase becomes more technical with about 31 Hydrochloric acid acidified (pH 1) and complete with hexane extracted After drying and evaporation, a raw hulupon (1.4 kg) with a hulnpon content is obtained

⁴⁹ ' ^5% · «0964 * 2 * 9

For further processing, the raw hulupon is dissolved in 101 hexane and mixed with aqueous propylene glycol Potassium hydroxide solution (150 g KOH in 9 1 water + 11 propylene glycol) extracted to a pH of 6.5. The aqueous phase is finally evaporated to a Hulupon concentration of ~ 20%.

This gives a product that is up to a concentration of 1% in water and up to > l% o is clearly soluble in beer and shows no tendency to "gushing".

Example 7

In a continuous apparatus consisting of a mixer, a hose pump, a thermostated reaction vessel with a gas mixing turbine and gas inlet with pressure equalization, as well as a suction filter, 1.74% lupulone solution in 0.3 η sodium hydroxide solution is added from a storage vessel. Finely powdered catalyst (10% cobalt oxide, 1% bismuth oxide on kieselguhr) is added to the mixer in such a way that the catalyst concentration is about 1%. This suspension is pumped by peristaltic pump into the reaction vessel and there atm by mixing gas with oxygen of an overpressure of about 0.1 to reaction at 50 ⁰ C. The mean residence time is about 10 minutes. The solution is then freed from the catalyst on the suction filter. This returns to the reaction process.

The aqueous alkaline solution no longer contains any unreacted lupulone. The hulupon yield based on lupulone is greater than 50%.

For further processing, sulfuric acid is added to pH <1 acidified and extracted with hexane. The hexane Hulupon solution is then by extraction with propylene glycolic potassium hydroxide solution (100 g KOH on 9 liters of water and 11 liters of propylene glycol) Purified up to pH 6.5 and concentrated by concentration to about 20% in an application-technically favorable one

ίο brought shape.

In technical implementation, a Basex hexane solution is normally the starting material. With Alkali is extracted from lupulone, which is an aqueous alkaline or aqueous methanolic lupulate solution results. This is mixed with the catalyst and gassed with oxygen. The catalyst is after a given reaction time filtered off, the filtrate acidified (to pH 1), then with hexane extracted, resulting in a Hulupon hexane solution as a crude product.

For purification, a targeted extraction with preferably KOH (possibly with propylene glycol added), which results in a potassium hulupat solution that can be used in concentrated or Diluted form is added to the beer or is blended with isohumulone or potassium isohumulate. One can also use the hexane solutions from the isohumulone extraction let it run in and then clean it together. The process can be very easily continuous

borrowed to perform.

Claims (4)

Claims: value of hops in spite of a decrease in the -acids, only Sr slowly sinks. A part of these transformation patent products are an oxidative degradation product of the. P, .a cöuren) referred to as Hulupone 1. Process for the catalytic oxidation of lupulones U «λ _{by solubility and} lupulones or lupulone-containing material to become 5. You zecnn Hulupones in a liquid polar, alkaline ^at S ^ ^m * "^. _The Hulupone as a bitter substance medium, expedient at pH 11 to 14, this inu ^ _{research ba} i _d ^ _{0n their} lupulones employed at 0 to 90 ⁰ C by means of oxygen or oxygen-J ^ SunTmit drr possibility of targeted halogenised gases in the presence of a Katelysators, J ^ Jg "" in Hulupone, characterized in that xo ™ ^; ^ ° _{abe the first} n is working as a catalyst finely dispersed noble metals or NachdenAnga _Natriumsu ifit in alcoholic OxydevonÜbergangsmetaUenderl and ?. side m_Gege nwart ^^ _(D lupulone. Wright, group as well as bismuth or cobalt oxide or solution m « b ^ ^ ₁ ^ _{D. W} right, mixtures of such oxides or their ions, or rroc. v. "<=. [19631). The yields were Mixtures thereof, optionally on carriers 15 J. ^ * ^ ^m _by 30%) and the reaction times applied long used and productive in an alkali Jfji "<™" ^m _Ebe nso _We nig the Einkonzentration was not exceeding 1-one works. U? » β / ^ _trium peroxy disulfate on lupulone in 2. The method according to claim 1, characterized by wainumpc ^ _{B urto n>} r. _ste . draws that a soluble complex of Ainanoi _v . ^ _{im) with yields of} noble metal or a transition metal as catalyst ao ^v ' ^{: n} ^ _a J; _ma , _28% Use sator _{in a further process (Γ} . _ΤΛς η 00 485? is material containing lupulon 3. The method according to claim 1 or 2 characterized by DT-AS "JJJ _{mi 0 treated} lt. The reaction is characterized by the fact that the carrier material is silica '" TncWorathylen ^^^ _{dje yields of} gur, activated carbon, calcium phosphate, magnesium ze ^en ^ ^he ^ indicated _r ⁿ _8ahnlichene materials with 39%, oxide, dolomite, clays or cation-, 5 g ^ "^^^ _rei nem lupulone showed that exchanger verwendeL Jj ¹ * _t" t _{<. 5r} hi; _c hen Hulugon yields 16% hardly 4. The method according to claim 1 to 3, characterized in that j £ «££ ™ ^ R _est L is composed of a mixture characterized that in a R ^ ons- "^ Ξ ^ · ^ unpleasant tasting sub-medium with an alkali concentration of 0.1 to 1 undefined, th u _B normal work ³ ° ^8t ^ _m ^ ^l ' _essence improvement of the implementation of Lupulons to Hulupons brought the photosensitized oxidation with O _t with exposure in the presence of a suitable.! Dye according to the elderly 35 Suggestion of DT-OS 22 17 134. If sufficient Oxygen supply is the conversion rate proportional to air irradiated light energy and can therefore be controlled as required by the strength of the light source. The Hulupon yields are around 50%. The invention relates to a process for producing ₄ o about 50%. Disadvantageous aj; ^ sem drive s.nd d, e