EP3922707A1 - Reduction of foul odors in bioethanol - Google Patents

Abstract

The present invention relates to the use of an additive mixture comprising at least one alkaline additive and at least one oxidizing agent for reducing off-odors in bioethanol. The present invention further relates to a method for reducing off-odors in bioethanol comprising an additive mixture and also a product produced by the method for reducing off-odors in bioethanol.

Description

The present invention relates to a use of an additive mixture for reducing off-odors in bioethanol. The present invention further relates to a method for reducing off-odors in bioethanol comprising an additive mixture and a product produced by the method for reducing off-odors in bioethanol.

Bioethanol is produced exclusively from biological waste or biological matter, such as sugar beet, potatoes, corn, grain, wood and straw, through fermentation, also known as alcoholic fermentation, using enzymes and microorganisms. Bioethanol has been used for biofuels, such as E10 and E5, for use in Otto combustion engines to replace mineral fuels since 2004. Bioethanol burns without soot, since only water and carbon dioxide are produced as waste products. Bioethanol is also used in the cosmetics industry.

Compared to conventional mineral fuels such as gasoline, bioethanol has a higher octane number, is almost sulfur-free and biodegradable, which makes it an environmentally friendly and, above all, renewable alternative to conventional mineral fuels. Bioethanol is not only a renewable raw material, it also enables it to be produced independently of oil deposits. Because it is manufactured through fermentation using enzymes and microorganisms, the commercially available bioethanol for biofuels has an unpleasant odor of burnt rubber and stables, which becomes even more intense when it evaporates. In anaerobic fermentation, in addition to bioethanol, hydrogen sulfide, for example, is produced, which contributes to the unpleasant odor. Despite the usual purification of bioethanol by distillation, a certain proportion of the hydrogen sulfide and other compounds are still dissolved in the purified bioethanol. Bioethanol is primarily intended to be used as fuel, which means that an unpleasant odor can be neglected. When used as petrol, this off-smell is not a major problem, but it is in other bioethanol applications.

DE 10 2012 024 111 A1 discloses a method for odor treatment of organic substrates, in which an odor treatment substance formed on the basis of iron chlorides is introduced or introduced into a bio-substrate. CN 103160336 discloses a bio-alcohol oil based on edible oil waste oil esters comprising a deodorant, the deodorant being camphor or ammonia. EP 1 884 555 A2 discloses a mineral oil wherein the mineral oil odor is masked. Masking mineral oil odor is understood to mean the complete or partial covering of the mineral oil maldor by a fragrance or a mixture of odorous substances, so that the sensory maldor impression is reduced or covered.

It is thus known from the prior art to carry out an odor treatment of biological oils and mineral oils by adding odorous substances such as camphor, essential oils, or catalysts such as ferrocene and iron chloride. Repeated cleaning by distillation can also be used to remove off-smells. However, these are expensive, energy-consuming and time-consuming methods.

The object of the present invention is to provide a bioethanol which does not have any unpleasant offensive odor.

This object is achieved according to the invention by using an additive mixture comprising at least one alkaline additive and at least one oxidizing agent for reducing off-odors in bioethanol, more preferably using a bioethanol treated with an additive mixture comprising at least one alkaline additive and at least one oxidizing agent for reducing off-odors as Cleaning agents and disinfectants or in the cosmetics industry.

When the bioethanol is purified after its production, fractions of different purity are created. The purest fraction is called neutral ethanol and has a purity of at least 99%. Neutral ethanol is used in the manufacture of alcoholic beverages and medical applications. Bioethanol, which is to be used for biofuels, does not need such a high degree of purity. This means that the proportion of water, sulfur-containing or other compounds in these fractions is higher. In order to be able to use cheaper bioethanol as a basis, for example for cosmetics or for disinfectants of any kind, this must be treated to remove the odor-intensive compounds, in particular Hydrogen sulfide, to neutralize. Further purification by distillation would not lead to a complete purification, but in turn to more heavily contaminated fractions and purer fractions. Such a distillation is also energy-intensive and therefore cost-intensive. The bioethanol to be treated according to the invention preferably has a purity of about 98% and higher.

The additive mixture according to the invention reduces the unpleasant offensive odor of the bioethanol to be treated. The odor reduction is brought about by a preferably two-stage reaction in bioethanol in order to break down the odor-forming compounds, in particular hydrogen sulfide. To reduce the offensive odor, the additive mixture comprises several components, including according to the invention at least one alkaline additive and at least one oxidizing agent, more preferably at least one triol and / or at least one denaturing agent, which are described in more detail below.

According to the invention, the additive mixture comprises at least one oxidizing agent. The at least one oxidizing agent is preferably selected from a group comprising hydrogen peroxide, ethane peroxy acid, sodium percarbonate, urea peroxohydrate or a mixture of these. An at least 10%, preferably at least 75%, aqueous solution of the at least one oxidizing agent is preferably used. For example, a 30% hydrogen peroxide solution has 9.8 mol / l hydrogen peroxide. The at least one oxidizing agent reacts with the odorous compounds present in the bioethanol to be treated. For example, hydrogen sulfide H ₂ S reacts with hydrogen peroxide to form sulfuric acid. The sulfuric acid formed is further converted by the at least one alkaline additive. The at least one oxidizing agent is preferably in a range from about 1% by weight to about 80% by weight, more preferably in a range from about 1.6% by weight to about 75% by weight, based on the total amount the additive mixture, comprised of this.

According to the invention, the additive mixture comprises at least one alkaline additive. The at least one alkaline additive is preferably selected from a group comprising potassium hydroxide, sodium hydroxide, primary amines, secondary amines, tertiary amines, sodium carbonate, potassium carbonate or a mixture of these. One is preferred at least 10% to preferably 50% aqueous solution of the at least one alkaline additive, in particular of sodium hydroxide and potassium hydroxide, is used. For example, a 20% strength potassium hydroxide solution has 4.21 mol / l potassium hydroxide. For example, a 20% sodium hydroxide solution has 6.09 mol / l sodium hydroxide. The at least one alkaline additive reacts with the compounds generated by the at least one oxidizing agent in the bioethanol to be treated. If, for example, potassium hydroxide is used, the reaction with sulfuric acid formed from hydrogen sulfide produces potassium sulfate K ₂ SO ₄ . As a result of the reaction, which can preferably be carried out in two stages, the odor-forming compounds are converted into stable and soluble ions. If an excess of the at least one alkaline additive is used, the resulting salt can precipitate. According to the invention, the precipitation of the resulting salt is preferably prevented by adjusting the pH. The at least one alkaline additive is preferably in an amount in a range from about 1% by weight to about 50% by weight, particularly preferably in a range from about 1.6% by weight to about 45% by weight, based on the total amount of the additive mixture, comprised by this.

The additive mixture preferably comprises at least one triol. The at least one triol is more preferably selected from a group comprising glycerol. The at least one triol is preferably comprised in a range from about 5% by weight to about 25% by weight, more preferably in a range from about 8% by weight to about 24% by weight, based on the total amount of Additive mixture.

The additive mixture preferably comprises at least one denaturant. The at least one denaturant is more preferably selected from a group comprising butanone, diethyl phthalate, thymol, isopropanol, tertiary butanol, denatonium benzoate, methyl ethyl ketone, methyl isopropyl ketone, ethyl isoamyl ketone (5-methyl-3-heptanone) and / or pyridine bases. Since the at least one oxidizing agent can react with the denaturing agent already added to the bioethanol, at least one denaturing agent must be added again to the treated bioethanol after odors have been removed by the additive mixture. The denaturants which can be used according to the invention preferably have a boiling point similar to that of ethanol, in order to prevent separation of the same when a distillation may still be carried out. Another selection criterion of the at least one denaturing agent is an intense, unpleasant taste at a low concentration in order to prevent the use of bioethanol without taxation for alcoholic beverages. The at least one denaturant is preferably in a range from about 0.0005% by weight to about 30% by weight, more preferably in a range from about 0.001% by weight to about 25% by weight, based on the total amount the additive mixture, comprised of this.

If, within the scope of the invention, the term "approximately" is used in connection with values or value ranges, this is to be understood as a tolerance range which the person skilled in the art in this field considers normal, in particular a tolerance range of ± 20%, preferably ± 10%, more preferably ± 5%, even more preferably ± 3%, are provided. The lower limit values claimed in the present invention and the upper limit values of the various ranges, in particular the weight percentage ranges, but not limited thereto, can be combined with one another to define new ranges.

Insofar as the term percent by weight or% by weight is used in relation to the components consisting of the claimed method and the claimed use, the term percent by weight relates to the amount of one or more components in relation to the total amount of the components used, usually the Additive mixture or the solution obtained in the process according to the invention, unless expressly stated otherwise. The term "wt .-%" is used throughout the present invention as an abbreviation for percent by weight, unless otherwise specified.

1. a) Verdünnen von Bioethanol durch mindestens ein Verdünnungsmittel;
2. b) Hinzufügen von einer Additivmischung umfassend mindestens einen alkalischen Zusatzstoff und mindestens ein Oxidationsmittel;
3. c) Homogenisieren der erhaltenen Lösung.

Furthermore, the present invention relates to a method for odor reduction in bioethanol comprising the steps:

1. a) dilution of bioethanol with at least one diluent;
2. b) adding an additive mixture comprising at least one alkaline additive and at least one oxidizing agent;
3. c) homogenizing the solution obtained.

According to the invention, bioethanol is treated with an offensive odor. That to be treated Bioethanol is in an amount in the range from about 20% by weight to about 97% by weight, even more preferably in an amount in a range from about 50% by weight to about 85% by weight, based on the total amount the solution obtained. The solution obtained comprises the bioethanol to be treated, the at least one diluent and the above-described additive mixture according to the invention.

According to the invention, a diluent is added to the bioethanol to be treated in process step a). The at least one diluent is preferably water. The at least one diluent is more preferably tap water or deionized water. Deionized water is water without the salts found in spring and tap water, which are dissolved as anions and cations, and is used in chemistry and biology as a solvent and sometimes also as a cleaning agent. Process step a) diluting the bioethanol to be treated is preferably carried out before process step b) adding an additive mixture. The at least one diluent is preferably in a range from about 3% by weight to about 80% by weight and more preferably in a range from about 5% by weight to about 50% by weight, based on the total amount of the solution obtained , covered by this.

The ratio between the amount of water and the amount of bioethanol is preferably in a range from about 0.2 to about 0.9, and even more preferably in a range from about 0.5 to about 0.8. The ratio between the amount of water and the amount of bioethanol is tailored to the use of the solution obtained.

According to the invention, the previously described additive mixture according to the invention is added to the bioethanol to be treated in process step b). According to the invention, the additive mixture is added sequentially. In the sequential addition of the additive mixture, the at least one oxidizing agent is preferably added to the bioethanol to be treated first, and then the at least one alkaline additive; alternatively, the oxidizing agent and the alkaline additive can also be added in reverse order or at the same time, depending on the compounds used . The at least one oxidizing agent is preferably in an amount in a range from about 0.01% by weight to about 8% by weight, particularly preferably in a range from about 0.02% by weight to about 7% by weight, based on the total amount of the solution obtained . In a preferred embodiment, after the addition of the at least one oxidizing agent, the at least one alkaline additive is added.

The pH of the solution obtained is preferably set in a range from about 7 to about 13 by means of the alkaline additive. To measure the pH, a sample of the solution obtained is separated off and diluted to such an extent that a water content of at least 50% by weight is reached. The pH value is then measured using a WTW 3310 pH meter with the SenTix 81 pH electrode manufactured by WTW at a temperature of 20 ° C. The at least one alkaline additive is preferably in an amount in a range from about 0.01% by weight to about 5% by weight, particularly preferably in a range from about 0.02% by weight to about 3% by weight. %, based on the total amount of the solution obtained, comprised of this.

The at least one denaturing agent is preferably added after the at least one oxidizing agent. The one denaturing agent is preferably added to the mixture obtained after a possible excess of the at least one oxidizing agent has been broken down. The at least one denaturant is preferably in an amount in a range from about 0.0001% by weight to about 5% by weight, particularly preferably in a range from about 0.0002% by weight to about 4% by weight , based on the total amount of the solution obtained, comprised by this.

The addition of at least one triol is preferably included in a further step. The at least one triol is preferably in an amount in a range from about 0.01% by weight to about 5% by weight, particularly preferably in a range from about 0.1% by weight to about 4% by weight , based on the total amount of the solution obtained from this.

In a further step, the addition of at least one reducing agent is preferred. The at least one reducing agent is more preferably selected from a group comprising ascorbic acid, sodium ascorbate, sulfites, thiosulfates, catalase or a mixture this. An excess of the at least one oxidizing agent is preferably neutralized by adding at least one reducing agent. By neutralizing the excess oxidizing agent, the solution obtained, also called treated bioethanol, is stable in storage. The at least one reducing agent is added dropwise to the resulting solution until there is no longer any excess oxidizing agent. The content of the at least one oxidizing agent is determined by a commercially available peroxide test, such as peroxide test sticks MQUANT ^® from Merck KGaA Germany. This determination of the content is repeated during the addition of the at least one reducing agent until the peroxide test no longer detects any oxidizing agent.

The sequential addition has the advantage of preventing the individual components of the additive mixture from reacting with one another. The additive mixture is preferably in an amount in a range from about 0.001% by weight to about 20% by weight, more preferably in a range from about 0.005% by weight to about 17.5% by weight, based on the Total amount of the solution obtained, added to this.

According to the invention, the solution obtained is homogenized in process step c). The homogenization can preferably be carried out during and after process steps a) and b). The homogenization according to the invention comprises, for example, stirring and / or shaking the solution obtained.

All process steps are preferably carried out at room temperature. Room temperature is the average room air temperature. The room temperature is preferably in a range from about 18 ° C to about 25 ° C, more preferably in a range from about 20 ° C to about 23 ° C.

The odor determination of the solution obtained within the meaning of the present invention is preferably carried out by at least two people who determine the odor independently of one another. The odor determination is carried out in a well-ventilated room. The samples are stored in tightly closed vessels, which must be odorless when closed. The samples are assessed at room temperature. With a pipette, 3 to 4 drops are placed on a surface heated to 30 ° C and passed into a thin film. The olfactory assessment of the evaporating sample film is assessed olfactorily by gently fanning the odor. The vessel is tightly closed again after each sample. As a comparison, this process is carried out immediately before the sample or after the sample, once with untreated bioethanol and once with pure ethanol. These steps can be repeated. An evaluation scheme for the off-odor of the bioethanol to be treated was developed. The evaluation scheme is divided into odor categories with key figures, as shown in Table 1 below. The sample to be assessed is divided by the individual into one of the odor categories and the decrease in the unpleasant odor is quantified with the code number 10 until it disappears completely and a transition to a neutral ethanol odor with a slightly fruity ester note is quantified with the code number 1. <b> Table 1 </b>: Presentation of the odor categories and the corresponding key figures Odor categories Is equivalent to identification number unpleasant, burnt rubber, stable odor and becomes even more intense as it evaporates untreated bioethanol 10 pungent, sulphurous odor 6th unpleasant isobutyric acid odor with a sulphurous sub-note 5 Odor similar to isobutyric acid and acetic acid 4th slightly acidic like vinegar 3 only a slight smell of vinegar is present 2 fruity ester note and neutral after evaporation pure ethanol ≥ 99% 1

The odor determination is carried out at several points in time. It is preferred to determine the odor at the time 0 hours, directly after the addition of the alkaline additive and / or oxidizing agent, and after the components have reacted the additive mixture according to the invention carried out with the bioethanol to be treated. The odor determination is carried out after the completion of method step c) of the aforementioned method according to the invention, which corresponds to the time 0 hours. The reaction of the components of the additive mixture is usually complete after 24 hours at the latest. A final odor determination is therefore preferably carried out 24 hours after the end of process step c).

The present invention further relates to a product produced by the aforementioned method according to the invention. The product according to the invention is the solution obtained, which in the present invention is also referred to as odorless treated bioethanol. The odor-free treated bioethanol is preferably used as a basis for cleaning agents and disinfectants or in the cosmetics industry.

The advantages achieved with the invention are that inexpensive, odor-intensive bioethanol can be treated quickly and inexpensively in order to reduce its off-odor, so that it can be used for new applications.

An exemplary use according to the invention of an additive mixture preferably comprises at least one alkaline additive in an amount in a range from about 1% by weight to about 50% by weight and at least one oxidizing agent in a range from about 1% by weight to about 80% by weight .-%, based on the total amount of the additive mixture, to reduce bad odors in bioethanol.

An exemplary use according to the invention of an additive mixture comprises even more preferably at least one alkaline additive in an amount in a range from about 1% by weight to about 50% by weight and at least one oxidizing agent in a range from about 1% by weight to about 80% by weight, based on the total amount of the additive mixture, to reduce bad odors in bioethanol, the at least one oxidizing agent being selected from a group comprising hydrogen peroxide, ethane peroxy acid, sodium percarbonate, urea peroxohydrate or a mixture of these.

An exemplary use according to the invention of an additive mixture encompasses even more preferably at least one alkaline additive in an amount in a range from about 1% by weight to about 50% by weight and at least one oxidizing agent in a range from about 1% by weight to about 80% by weight, based on the Total amount of the additive mixture to reduce off-odors in bioethanol, the at least one alkaline additive being selected from a group comprising potassium hydroxide, sodium hydroxide, primary amines, secondary amines, tertiary amines, sodium carbonate, potassium carbonate or a mixture of these.

An exemplary use according to the invention of an additive mixture comprises even more preferably at least one alkaline additive in an amount in a range from about 1% by weight to about 50% by weight and at least one oxidizing agent in a range from about 1% by weight to about 80% by weight, based on the total amount of the additive mixture, for reducing off-odors in bioethanol, the additive mixture comprising at least one triol, the at least one triol preferably being selected from a group comprising glycerol and the at least one triol preferably being in a range from about 5% by weight to about 25% by weight, based on the total amount of the additive mixture.

An exemplary use according to the invention of an additive mixture comprises even more preferably at least one alkaline additive in an amount in a range from about 1% by weight to about 50% by weight and at least one oxidizing agent in a range from about 1% by weight to about 80% by weight, based on the total amount of the additive mixture, for reducing off-odors in bioethanol, the additive mixture further preferably comprising at least one denaturing agent, the at least one denaturing agent being selected from a group comprising butanone, diethyl phthalate, thymol, isopropanol, and tertiary butanol , Denatonium benzoate, methyl ethyl ketone, methyl isopropyl ketone, ethyl isoamyl ketone (5-methyl-3-heptanone) and / or pyridine bases, and wherein the at least one denaturant is preferably comprised in a range from about 0.0005% by weight to about 30% by weight , based on the total amount of the additive mixture.

An exemplary use according to the invention of an additive mixture preferably comprises at least one alkaline additive in an amount in a range of about 1% by weight up to about 45% by weight and at least one oxidizing agent in a range from about 1% by weight to about 75% by weight, based on the total amount of the additive mixture, to reduce bad odors in bioethanol.

An exemplary use according to the invention of an additive mixture preferably comprises at least one alkaline additive in an amount in a range from about 1.6% by weight to about 45% by weight and at least one oxidizing agent in a range from about 1.6% by weight up to about 75% by weight, based on the total amount of the additive mixture, to reduce off-smells in bioethanol.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%-Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei sich die Gew.-%- Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, soweit nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the weight percentages of the at least one alkaline additive and of the at least one oxidizing agent being based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

where the percentages by weight in each case relate to the total amount of the solution obtained, unless stated otherwise.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%- Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei das mindestens eine Verdünnungsmittel bevorzugt Wasser ist, weiter bevorzugt ist das mindestens eine Verdünnungsmittel Leitungswasser oder deionisiertes Wasser, wobei sich die Gew.-%- Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, falls nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the% by weight of the at least one alkaline additive and the at least one oxidizing agent are based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

where the at least one diluent is preferably water, more preferably the at least one diluent is tap water or deionized water, the percentages by weight each referring to the total amount of the solution obtained, unless otherwise stated.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%- Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei der mindestens eine alkalische Zusatzstoff ausgewählt ist aus einer Gruppe umfassend Kaliumhydroxid, Natriumhydroxid, primäre Amine, sekundäre Amine, tertiäre Amine, Natriumcarbonat, Kaliumcarbonat oder einer Mischung dieser, wobei sich die Gew.-%- Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, falls nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the weight percentages of the at least one alkaline additive and of the at least one oxidizing agent being based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

the at least one alkaline additive being selected from a group comprising potassium hydroxide, sodium hydroxide, primary amines, secondary amines, tertiary amines, sodium carbonate, potassium carbonate or a mixture of these, the weight percentages each referring to the total amount of the solution obtained unless otherwise stated.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%- Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei das mindestens eine Oxidationsmittel ausgewählt ist aus einer Gruppe umfassend Wasserstoffperoxid, Ethanperoxosäure, Natriumpercarbonat, Harnstoffperoxohydrat oder einer Mischung dieser, wobei sich die Gew.-%- Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, falls nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the weight percentages of the at least one alkaline additive and of the at least one oxidizing agent being based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

the at least one oxidizing agent being selected from a group comprising hydrogen peroxide, ethane peroxy acid, sodium percarbonate, urea peroxohydrate or a mixture of these, the weight percentages relating in each case to the total amount of the solution obtained, unless otherwise stated.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%- Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei die Additivmischung mindestens ein Triol umfasst, wobei weiter bevorzugt das mindestens eine Triol ausgewählt ist aus einer Gruppe umfassend Glycerin und wobei das zumindest eine Triol bevorzugt in einem Bereich von etwa 0,01 Gew.-% bis etwa 5 Gew.-% umfasst ist, wobei sich die Gew.-%- Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, falls nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the weight percentages of the at least one alkaline additive and of the at least one oxidizing agent being based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

wherein the additive mixture comprises at least one triol, wherein the at least one triol is more preferably selected from a group comprising glycerol and wherein the at least one triol is preferably comprised in a range from about 0.01% by weight to about 5% by weight , the percentages by weight in each case being based on the total amount of the solution obtained, unless stated otherwise.

1. a) Verdünnen von etwa 20 Gew.-% bis etwa 97 Gew.-% Bioethanol durch etwa 3 Gew.-% bis etwa 80 Gew.-% mindestens eines Verdünnungsmittels;
2. b) Hinzufügen von etwa 0,001 Gew.- % bis etwa 20 Gew.-% einer Additivmischung umfassend etwa 0,01 Gew.-% bis etwa 50 Gew.-% mindestens eines alkalischen Zusatzstoffes und etwa 0,01 Gew.-% bis etwa 80 Gew.-% mindestens eines Oxidationsmittels, wobei die Gew-%- Angaben des mindestens einen alkalischen Zusatzstoffes und des mindestens einen Oxidationsmittels bezogen sind auf die Gesamtmenge der Additivmischung;
3. c) Homogenisieren der erhaltenen Lösung,

wobei die Additivmischung weiter bevorzugt mindestens ein Vergällungsmittel umfasst, wobei das mindestens eine Vergällungsmittel ausgewählt ist aus einer Gruppe umfassend Butanon, Phthalsäurediethylester, Thymol, Isopropanol, Tertiärbutanol, Denatoniumbenzoat, Methylethylketon, Methylisopropylketon, Ethylisoamylketon (5-Methyl-3-heptanon) und/oder Pyridinbasen, und wobei das mindestens eine Vergällungsmittel bevorzugt in einem Bereich von etwa 0,0001 Gew.-% bis etwa 5 Gew.-% umfasst ist, wobei sich die Gew.-%-Angaben jeweils auf die Gesamtmenge der erhaltenen Lösung bezieht, falls nicht anders angegeben.An exemplary method according to the invention for odor reduction in bioethanol preferably comprising the steps:

1. a) diluting from about 20% by weight to about 97% by weight of bioethanol with about 3% by weight to about 80% by weight of at least one diluent;
2. b) adding about 0.001% by weight to about 20% by weight of an additive mixture comprising about 0.01% by weight to about 50% by weight of at least one alkaline additive and about 0.01% by weight to about 80% by weight of at least one oxidizing agent, the% by weight data of the at least one alkaline additive and of the at least one oxidizing agent being based on the total amount of the additive mixture;
3. c) homogenizing the solution obtained,

wherein the additive mixture further preferably comprises at least one denaturant, the at least one denaturant being selected from a group comprising butanone, diethyl phthalate, thymol, isopropanol, tertiary butanol, denatonium benzoate, methyl ethyl ketone, methyl isopropyl ketone, ethyl isoamyl ketone (5-methyl-3-heptanone) and / or Pyridine bases, and wherein the at least one denaturing agent is preferably comprised in a range from about 0.0001% by weight to about 5% by weight, the% by weight information relating in each case to the total amount of the solution obtained, if not stated otherwise.

The above preferred embodiments of the use according to the invention of an additive mixture, the method according to the invention and the product produced by the method according to the invention are non-limiting preferred examples. A combination of the named areas and components of each example with one or more other examples is also possible. The present invention is described in more detail below with reference to the non-limiting exemplary embodiments.

• Methode 1: Die Probe wurde 1:1 in deionisiertem Wasser verdünnt. Anschließend wurde der pH-Wert gemessen mittels eines pH-Meters WTW 3310 mit einer pH Elektrode SenTix 81, hergestellt von WTW Xylem Analytics Germany Sales GmbH & Co. KG Deutschland, für einen Messbereich von 0 pH bis 14 pH und verwendbar in einem Temperaturbereich von 0°C bis 100°C, wobei die pH-Wert Messung bei 20°C durchgeführt wurde. Das pH-Meter wurde mittels der Pufferlösungen WTW-Pufferlösung pH 9.180, WTW-Pufferlösung pH 6.865, WTW-Pufferlösung pH 4.006 und WTW-Pufferlösung pH 1.679 durch Titration mit einer 3 mol/l Kaliumchlorid-Lösung kalibriert.
• Methode 2: Bei einer unverdünnten Probe wurde der pH-Wert zusätzlich mittels pH-Indikatorstäbchen gemessen, wobei das pH-Indikatorstäbchen ein nicht blutender Universal Indikator für den pH-Wert Bereich von pH 0 bis pH 14 vorgesehen ist und von Merck KGaA stammt. Die pH-Wert Messung wurde bei Raumtemperatur durchgeführt.

The pH value measurement was carried out using two methods. to verify the pH:

• Method 1: The sample was diluted 1: 1 in deionized water. The pH was then measured using a WTW 3310 pH meter with a SenTix 81 pH electrode, manufactured by WTW Xylem Analytics Germany Sales GmbH & Co. KG Germany, for a measuring range from 0 pH to 14 pH and usable in a temperature range of 0 ° C to 100 ° C, with the pH value measurement being carried out at 20 ° C. The pH meter was measured using the buffer solutions WTW buffer solution pH 9.180, WTW buffer solution pH 6.865, WTW buffer solution pH 4.006 and WTW buffer solution pH 1.679 by titration with a 3 mol / l potassium chloride solution calibrated.
• Method 2: The pH value of an undiluted sample was also measured using a pH indicator stick, the pH indicator stick being a non-bleeding universal indicator for the pH value range from pH 0 to pH 14 and coming from Merck KGaA. The pH value measurement was carried out at room temperature.

The same values were determined with both pH measurements.

The following compounds were used in working examples A1 to A7 according to the invention and comparative example A8 in Table 2.

Bioethanol with a purity of 98.7% by volume was used. Deionized water was used as a diluent. Glycerin with a purity of 86.5% was also used. Aqueous sodium hydroxide solution was used as an alkaline additive in a concentration of 6.09 mol / l, which corresponds to a 20% solution. Aqueous potassium hydroxide solution was used as an alkaline additive with a concentration of 4.21 mol / l, which corresponds to a 20% solution. A hydrogen peroxide solution with a concentration of 9.80 mol / l, which corresponds to a 30% solution, and with a pH value of 3.5 pH at 20 ° C. and a density of 1.11 g was used as the oxidizing agent / ml used at 20 ° C. White, powdery sodium percarbonate with a purity of 99% was used as the oxidizing agent. Ethanolamine as an alkaline additive was used with a density of 1.02 g / ml, a kinematic viscosity of 20 mm ² / s at 23 ° C. and a purity of 99%. Solutions according to Table 2 below and the description of the experiment below were prepared from the aforementioned components.

Bioethanol was placed in a sealable reaction vessel at room temperature. Deionized water was added to the submitted bioethanol. After the bioethanol-water solution was homogenized, hydrogen peroxide was added. After all of the hydrogen peroxide had been added, the alkaline additive and, if necessary, further components, such as glycerine, were added. The resulting solution was homogenized by stirring. The first odor determination according to the aforementioned method and a pH value measurement by a pH meter WTW 3310 with the pH electrode SenTix 81 at 20 ° C was carried out at the time 0 hours. After 24 hours, a second odor determination and pH value measurement were carried out.

The composition of the solutions of working examples A1 to A7 according to the invention and a comparative example A8 are shown in Table 2 below, the amounts being given in% by weight, based on the total amount of the composition. Table 2: Composition of the solutions of working examples A1 to A7 according to the invention and comparative example A8. A1 A2 A3 A4 A5 A6 A7 A8 Bioethanol 75.51 75.51 75.51 75.51 75.51 75.51 75.51 75.51 deionized water 17.86 20.22 15.84 22.27 16.41 17.33 15.4 17.84 Glycerin 0 2.02 2.02 2.02 2.02 2.02 2.02 2.02 Potash lye [20% solution] 2.00 2.00 2.00 0.1 0 0 2.00 0 Caustic soda [20% solution] 0 0 0 0 1.43 0 0 0 Hydrogen peroxide [30% solution] 4.63 0.25 4.63 0.1 4.63 4.63 0 4.63 Sodium percarbonate 0 0 0 0 0 0 7.07 0 Ethanolamine 0 0 0 0 0 0.51 0 0

The odor determination of working examples A1 to A7 according to the invention and of comparative example A8 was carried out after carrying out the above-mentioned method at time 0 h and a further odor determination was carried out after 24 h. The experimental results of the odor determination of working examples A1 to A7 according to the invention and comparative example A8 are listed in Table 3 below. <b> Table 3: </b> Evaluation of the odor determination of the inventive working examples A1 to A7 and the comparative example A8. A1 A2 A3 A4 A5 A6 A7 A8 pH value at 0h 11.5 12.5 11.5 9.5 10 10 10 3 Odor index at 0h 10 10 10 10 10 10 10 10 pH value after 24h 11.5 12.5 11.5 8th 10 10 10 3 Odor index after 24 hours 1 1 1 1 1 3 1 6th

The embodiment example A1 with 20% potassium hydroxide solution and 30% hydrogen peroxide shows a complete odor reduction after 24 hours. The exemplary embodiments A2 and A3 with potassium hydroxide solution, glycerine and hydrogen peroxide, like A1, have a complete odor reduction with a hydrogen peroxide content of 0.1% by weight and 4.63% by weight. The off-odor can thus be completely reduced by adding hydrogen peroxide in a range from 0.1% by weight to 5% by weight of the 30% strength hydrogen peroxide solution used. The off-odor in exemplary embodiment A4 is reduced to 1 after 24 hours. A low hydrogen peroxide content and a low potassium hydroxide content according to A4 indicate a constant reduction in odor, even at a slightly lower pH value. A5 has no off-odor after 24 hours, which suggests that caustic soda can be used as an alternative to caustic potash. Exemplary embodiment A6 with ethanolamine as the alkaline additive still had a slight off-odor "slightly acidic like vinegar" corresponding to the odor index 3 after 24 hours. Obviously, ethanolamine, as an alkaline additive, is somewhat inferior to potassium hydroxide and sodium hydroxide solution with the same hydrogen peroxide content, but nevertheless delivers good results. The exemplary embodiment A7 with sodium percarbonate as the oxidizing agent shows comparable results to the exemplary embodiment A3 with hydrogen peroxide. Comparative example A8 with an odor index of 6 after 24 hours does not show a complete reduction in the off-odor. The pH of Comparative Example A8 is 3 pH, which is likely to explain the insufficient reduction in the off-odor of the bioethanol and the lack of the alkaline additive.

The examples of the use according to the invention of an additive composition in the process according to the invention comprising in particular sodium hydroxide solution and / or potassium hydroxide solution as an alkaline additive and hydrogen peroxide as an oxidizing agent clearly show that these combinations in particular can completely reduce an off-smell of bioethanol and thus provide an inexpensive, simple option, bioethanol can also be used for other commercial purposes, especially in the field of disinfectants and cosmetics.

Claims (19)

Use of an additive mixture comprising at least one alkaline additive and at least one oxidizing agent to reduce bad odors in bioethanol. Use according to claim 1, characterized in that the at least one alkaline additive is selected from a group comprising potassium hydroxide, sodium hydroxide, primary amines, secondary amines, tertiary amines, sodium carbonate, potassium carbonate or a mixture of these. Use according to one or more of the preceding claims, characterized in that the at least one alkaline additive is included in an amount in a range from about 1% by weight to about 50% by weight, based on the total amount of the additive mixture . Use according to one or more of the preceding claims, characterized in that the at least one oxidizing agent is selected from a group comprising hydrogen peroxide, ethane peroxy acid, sodium percarbonate, urea peroxohydrate or a mixture of these. Use according to one or more of the preceding claims, characterized in that the at least one oxidizing agent is included in a range from about 1% by weight to about 80% by weight, based on the total amount of the additive mixture. Use according to one or more of the preceding claims, characterized in that the additive mixture comprises at least one triol. Use according to one or more of the preceding claims, characterized in that the at least one triol is selected from a group comprising glycerol. Use according to one or more of the preceding claims, characterized in that the at least one triol is comprised in a range from about 5% by weight to about 25% by weight, based on the total amount of the additive mixture. Use according to one or more of the preceding claims, characterized in that the additive mixture comprises at least one denaturant. Use according to one or more of the preceding claims, characterized in that the at least one denaturant is selected from a group comprising butanone, diethyl phthalate, thymol, isopropanol, tertiary butanol, denatonium benzoate, methyl ethyl ketone, methyl isopropyl ketone, ethyl isoamyl ketone (5-methyl-3-heptanone) and / or pyridine bases. Use according to one or more of the preceding claims, characterized in that the at least one denaturing agent is included in a range from about 0.0005% by weight to about 30% by weight, based on the total amount of the additive mixture. Process for odor reduction in bioethanol comprising the steps: a) dilution of bioethanol with at least one diluent; b) adding an additive mixture comprising at least one alkaline additive and at least one oxidizing agent; c) homogenizing the solution obtained. Process according to claim 12, characterized in that the at least one diluent is water. Process according to one or more of Claims 12 and 13, characterized in that the at least one diluent is comprised of this in a range from about 3% by weight to about 80% by weight, based on the total amount of the solution obtained. Process according to one or more of Claims 12 to 14, characterized in that the additive mixture is added in an amount in a range from about 0.001% by weight to about 20% by weight, based on the total amount of the solution obtained. Process according to one or more of Claims 12 to 15, characterized in that it comprises the further step of adding at least one triol. Method according to one or more of Claims 12 to 16, characterized in that a pH value of the resulting solution in a range from about 7 to about 13 is set by means of the alkaline additive. Process according to one or more of Claims 12 to 17, characterized in that all process steps are carried out at room temperature. Product produced by a method according to one or more of claims 12 to 18.