Novel coolant compositions

Abstract

Novel coolant compositions for cooling systems based on renewable feedstocks are described.

Description

[0001] Description

[0002] The present invention describes a new coolant composition for cooling systems based on renewable raw materials.

[0003] The coolant for the cooling circuit of mobile or stationary combustion engines, however also for electric cars or vehicles with electric motors and combustion engines, is usually a liquid mixture of water, glycol components, corrosion inhibitors and other constituents.

[0004] The glycol component which lowers the freezing point is here usually monoethylene glycol and / or monopropylene glycol, predominantly monoethylene glycol.

[0005] In industry, monoethylene glycol is usually produced by ring-opening reaction of oxirane with water, wherein the oxirane is produced from ethylene, which in turn is obtained by cracking fossil naphtha in a steam cracker.

[0006] This production route has at least the following disadvantages:

[0007] - fossil raw materials are a limited resource

[0008] - the use of fossil raw materials increases the carbon footprint, resulting in a poorer ecological balance of the products obtained

[0009] - oxirane as a carcinogenic substance, due to its high toxicity and its safety-technical properties (flash point, ignition temperature, explosion limit), can only be produced and handled under strict safety measures

[0010] - the reaction of oxirane with water not only produces the desired monoethylene glycol, but also higher oligomers in different proportions, in particular diethylene glycol, triethylene glycol, etc.

[0011] These higher oligomers have to be separated from the monoethylene glycol in a complex manner, usually in a distillation manner, but are also retained in small amounts in the monoethylene glycol. The presence of higher oligomers leads on the one hand to inconsistent product boiling points and on the other hand, the higher alkylene glycols often act as emulsifiers or foaming agents, so that a high proportion of higher alkylene glycols causes foaming when mixed with water at the end user.

[0012] Since the boiling point of monoethylene glycol at normal pressure is about 197°C, the separation of the higher oligomers by distillation with heat supply and generation of a vacuum requires a large amount of energy, wherein the separation of the higher oligomers is incomplete.

[0013] In practice, monopropylene glycol (1,2-propylene glycol) is used in very rare cases instead of monoethylene glycol as a freezing point reducing glycol component. However, the problem is essentially the same, since 1,2-propylene glycol is likewise produced from propylene oxide, which in turn is produced from propylene, which is likewise obtained from naphtha.

[0014] It is an object of the present application to provide a coolant which reduces the above-mentioned disadvantages, in particular the high carbon footprint.

[0015] This object is achieved by a coolant comprising monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, as a freezing point reducing glycol component, which is at least partially obtained from a renewable raw material.

[0016] The production of glycols, in particular monoethylene glycol, from renewable raw materials is well known. As a C2 body, monoethylene glycol can be obtained, by way of example, by fundamentally different routes:

[0017] - from C1 compounds, by C2 building and C-C bonding

[0018] - from C2 compounds, usually by oxidation or reduction

[0019] - from compounds having at least 3 carbon atoms, by carbon skeleton degradation and / or decomposition

[0020] These production variants are briefly described as follows:

[0021] obtained from c1 compounds

[0022] The production of ethylene glycol from C1 compounds can preferably be carried out from a CO2- and / or CO-containing gas or gas mixture in the presence of a reducing equivalent (for example hydrogen), particularly preferably in a biological process.

[0023] A preferred method is described in WO 2019 / 126400 A1. Therein, a gas mixture comprising hydrogen (H2) and carbon dioxide (CO2) and / or carbon monoxide (CO) is converted by a genetically modified microorganism into monoethylene glycol or possible precursors of monoethylene glycol (see below for the explanation of C2 compounds).

[0024] Here, the genetic modification can refer to the formation of foreign heterologous enzymes for the conversion of oxaloacetate into citrate, glycine into glyoxylate, isocitrate into glyoxylate, glycolate into glycolaldehyde.

[0025] This can be the following enzymes:

[0026] For the conversion of oxaloacetate to citrate: citrate [Si] synthase [2.3.3.1], ATP citrate synthase [2.3.3.8]; or citrate (Re) synthase [2.3.3.3].

[0027] For the conversion of glycine to glyoxylate: alanine-glyoxylate transaminase [2.6.1.44], serine-glyoxylate transaminase [2.6.1.45], serine-pyruvate transaminase [2.6.1.51], glycine-oxaloacetate transaminase [2.6.1.35], glycine transaminase [2.6.1.4], glycine dehydrogenase [1.4.1.10], alanine dehydrogenase [1.4.1.1] or glycine dehydrogenase [1.4.2.1].

[0028] For the conversion of isocitrate to glyoxylate: isocitrate lyase [4.1.3.1].

[0029] For the conversion of glycolate to glyoxylate: glycolate dehydrogenase [1.2.1.21], lactaldehyde dehydrogenase [1.2.1.22], succinate semialdehyde dehydrogenase [1.2.1.24], 2,5-dioxopentanoate dehydrogenase [1.2.1.26], aldehyde dehydrogenase [1.2.1.3 / 4 / 5], betaine aldehyde dehydrogenase [1.2.1.8] or aldehyde ferredoxin oxidoreductase [1.2.7.5].

[0030] Such enzymes can be obtained from microorganisms selected from the group consisting of Bacillus, Clostridium, Escherichia, Gluconobacter, Hyphomicrobium, Lysinibacillus, Paenibacillus, Pseudomonas, Sedimenticola, Sporosarcina, Streptomyces, Thermithiobacillus, Thermotoga and Zea.

[0031] Microorganisms comprising enzymes selected from the group consisting of isocitrate dehydrogenase, glycolate dehydrogenase, glycolate dehydrogenase, glycolate dehydrogenase, aldehyde ferredoxin oxidoreductase and aldehyde dehydrogenase are also feasible.

[0032] In a preferred embodiment, the microorganism is selected from the group consisting of Acetobacterium, Alkalibaculum, Blautia, Butyribacterium, Clostridium, Eubacterium, Moorella, Oxobacter, Sporomusa and Thermoanaerobacter. Especially preferred, they are selected from the group consisting of Acetobacterium woodii, Alkalibaculum bacchii, Blautia producta, Butyribacterium methylotrophicum, Clostridium aceticum, Clostridium autoethanogenum, Clostridium carboxidivorans, Clostridium coskatii, Clostridium drakei, Clostridium formicoaceticum, Clostridium ljungdahlii, Clostridium magnum, Clostridium ragsdalei, Clostridium scatologenes, Eubacterium limosum, Moorella thermoautotrophica, Moorella thermoacetica, Oxobacter pfennigii, Sporomusa ovata, Sporomusa silvacetica, Sporomusa sphaeroides and Thermoanaerobacter kiuvi, in particular from the group consisting of Clostridium autoethanogenum, Clostridium ljungdahlii and Clostridium ragsdalei.

[0033] The above-mentioned enzymes or their coding nucleic acids are preferably expressed in microorganisms selected from the group consisting of Bacillus, Clostridium, Escherichia, Gluconobacter, Hyphomicrobium, Lysinibacillus, Paenibacillus, Pseudomonas, Sedimenticola, Sporosarcina, Streptomyces, Thermithiobacillus, Thermotoga, Zea, Klebsiella, Mycobacterium, Salmonella, Mycobacteroides, Staphylococcus, Burkholderia, Listeria, Acinetobacter, Shigella, Neisseria, Bordetella, Streptococcus, Enterobacter, Vibrio, Legionella, Xanthomonas, Serratia, Cronobacter, Cupriavidus, Helicobacter, Yersinia, Cutibacterium, Francisella, Pectobacterium, Arcobacter, Lactobacillus, Shewanella, Erwinia, Sulfurospirillum, Peptococcaceae, Thermococcus, Saccharomyces, Pyrococcus, Glycine, Homo, Ralstonia, Brevibacterium,Methylobacterium, Geobacillus, bos, gallus, Anaerococcus, Xenopus, Amblyrhynchus, rattus, mus, sus, Rhodococcus, Rhizobium, Afegasphaera, Mesorhizobium, Peptococcus, Agrobacterium, Campylobacter, Acetobacterium, Alkalibaculum, Blautia, Butyribacterium, Eubacterium, Moorella, Oxobacter, Sporomusa, Thermoanaerobacter, Schizosaccharomyces, Paenibacillus, Fictibacillus, Lysinibacillus, Ornithinibacillus, Halobacillus, Kurthia, Lentibacillus, Anoxybacillus, Solibacillus, Virgibacillus, Alicyclobacillus, Sporosarcina, Salimicrobium, Sporosarcina, Planococcus, Corynebacterium, Thermaerobacter, Sulfobacillus, and Symbiobacterium.

[0034] Preferably, microorganisms genetically engineered in at least one of the enzymes mentioned above are used, selected from the group consisting of Clostridium acetobutylicum, Clostridium beijerinckii, Escherichia coli, Saccharomyces cerevisiae, Acetobacterium woodii, Alkalibaculum bacchii, Blautia producta, Butyribacterium methylotrophicum, Clostridium aceticum, Clostridium autoethanogenum, Clostridium carboxidivorans, Clostridium coskatii, Clostridium drakei, Clostridium formicoaceticum, Clostridium ljungdahlii, Clostridium magnum, Clostridium ragsdalei, Clostridium scatologenes, Eubacterium limosum, Moorella thermautotrophica, Moorella thermoacetica, Oxobacter pfennigii, Sporomusa ovata, Sporomusa silvacetica, Sporomusa sphaeroides and Thermoanaerobacter kiuvi, particularly selected from the group consisting of Clostridium autoethanogenum, Clostridium ljungdahlii and Clostridium ragsdalei, particularly Clostridium autoethanogenum LZ1561, as described in WO 2012 / 015317.

[0035] The carbon dioxide (CO2) and / or carbon monoxide (CO) used can come from any source, for example from off-gases, combustion gases, fermentation gases, synthesis gases or from air capture (also known as carbon capture (CC) or carbon capture and utilization (CCU)).

[0036] The use of carbon dioxide (CO2) and / or carbon monoxide (CO) in the process is advantageous if it does not have a carbon footprint specifically for this process, i.e. if it is not produced exclusively for this process from fossil sources. Conversely, the use of carbon dioxide (CO2) and / or carbon monoxide (CO) from off-gases or combustion gases is advantageous, as they would otherwise be released into the atmosphere if they were not used in this process.

[0037] Preferably, the carbon dioxide (CO2) and / or carbon monoxide (CO) used in the process comes from a renewable raw material, for example from a combustion process or fermentation.

[0038] It is also advantageous to capture carbon dioxide (CO2) from the air and use it in the process (carbon capture and utilization (CCU)). In this case, the monoethylene glycol obtained from the process represents a carbon sink.

[0039] In addition to monoethylene glycol, the product mixture obtained from the process can also contain biosynthetic precursors thereof, such as glycolic acid, glyoxylic acid and / or glycolaldehyde. In order to convert these to the desired product monoethylene glycol, the reaction mixture can thus be subjected to a hydrogenation treatment, if appropriate.

[0040] The reaction mixture is usually present in the form of an aqueous solution, from which the monoethylene glycol can be separated, if appropriate, by distillation, rectification or stripping (hereinafter collectively referred to as distillation). Due to the relatively low boiling points of the reaction by-products, the energy consumption in the distillation is lower than in the separation of monoethylene glycol from higher oligomers in the reaction of ethylene oxide with water.

[0041] In addition, the separation of monoethylene glycol can also be carried out via non-distillation methods, such as membrane filtration or reverse osmosis. Combinations of distillation and non-distillation methods are also conceivable.

[0042] As an example of a process for preparing a precursor of monoethylene glycol starting from a non-CO or CO2 C1 source, mention is made of the preparation of oxalic acid or a salt thereof from formic acid or a salt thereof. This is usually carried out in the form of an alkali metal formate, such as sodium or potassium formate, by reaction with a strong base, such as a metal hydride or an alkali metal hydroxide, in particular sodium hydroxide. However, this method is less preferred.

[0043] It is also possible to prepare glycolaldehyde by the reaction of formaldehyde with carbon monoxide and hydrogen in a hydroformylation. The glycolaldehyde obtained in this way is then hydrogenated to monoethylene glycol, as described in US 4496781 B1.

[0044] In another embodiment, CO2 and / or CO can be hydrogenated to methanol, which is converted to ethylene in a methanol-to-olefins (MTO) process, the ethylene is oxidized to ethylene oxide, and the ethylene oxide is converted to monoethylene glycol with water.

[0045] The hydrogenation of carbon oxides, in particular carbon dioxide, to methanol is known:

[0046] Kristian Stangeland, Hailong Li, Zhixin Yu, Energy, Ecology and Environment, Vol. 5, pages 272-285 (2020) summarizes suitable catalyst systems. The process requires a multi-component catalyst system. The interaction between the components is crucial for the high activity and selectivity of the CO2-to-methanol catalyst. This has been verified in numerous catalyst systems consisting of various metals (e.g. Cu, Pd, Ni) and metal oxides (e.g. ZnO, ZrO2, In2O3). These complex systems can contain a mixture of metallic, alloyed and metal oxide phases. At present, the most promising catalyst systems for large-scale processes are Cu-based and In-based catalysts, as they have excellent catalytic properties.

[0047] The synthesis process of CO2 to methanol can be carried out, for example, using the method known from DE-A-42 20 865, in which methanol is produced under the action of a silent discharge.

[0048] Alternatively and preferably, the synthesis of methanol can also be carried out in a thermal reactor at pressure and high temperature and in the presence of a copper-based catalyst (DE 43 32 789 A1 ; DE 19739773 A1 ).

[0049] Typical catalysts are for example described in the paper “Catalytic properties of Cu-based catalysts containing Zr and / or V for methanol synthesis from a carbon dioxide and hydrogen mixture” by N. Kanoun et al. in Catalysis Letters 15 (1992) 231-235. Potential catalysts such as CuO / ZnO and Cu-ZnO-Al2O3 are also described in “Methanol Synthesis from CO2: A Review of the Latest Developments in Heterogeneous Catalysis” by R. M. Navarro et al. published in Materials (2019), 12, 3902 and in “Catalytic carbon dioxide hydrogenation to methanol: A review of recent studies” published in Chemical Engineering Research and Design 92 (2014) 2557-2567.

[0050] A highly selective catalyst In2O3 / ZrO2 for industrial relevant conditions has also been described recently. Typical ranges for industrial relevant conditions for the hydrogenation of CO2 to methanol are T = 200-300 °C, p = 10-50 MPa and a gas hourly space velocity (GHSV) of 16000-48000 h-1. -1 (Angew. Chem. Int. Ed. 2016, 55, 6261-6265).

[0051] This step can be performed in the presence of a copper zinc alumina catalyst. When using a copper zinc alumina catalyst, the temperature is preferably in the range of 150 °C to 300 °C, preferably 175 °C to 300 °C, and the pressure is preferably in the range of 10 bar to 150 bar (abs).

[0052] The conversion of methanol to ethylene oxide is for example described in US 2002 / 132864 A1 and the subsequent conversion of ethylene oxide to monoethylene glycol with water is an industry standard.

[0053] In a preferred embodiment, this hydrogenation treatment is carried out using hydrogen which is not obtained from fossil sources, but by electrolysis of water, wherein it is particularly preferred that the electricity used for the electrolysis comes from renewable energy sources. Hydrogen obtained by electrolysis of water is characterized in that it has a deuterium content which is lower than the natural proportion, preferably lower than 90 ppm. This low deuterium content is then also reflected in the corresponding subsequent products. A process for the production of methanol from CO2is described in WO 2023 / 213583, the production of monoethylene glycol is described in the unpublished European patent application with the application number 23206933.6, filed on October 31, 2023. According to the latter application, a particularly preferred monoethylene glycol has a deuterium content of not more than 117 ppm, preferably not more than 115 ppm, particularly preferably not more than 113 ppm, most preferably not more than 110 ppm.

[0054] obtained from c2 compounds

[0055] In this production variant, the existing C2carbon skeleton is usually modified by oxidation or reduction, wherein the C2body which is the basis for the reaction comes at least partially, preferably completely, from natural sources or is obtained from renewable raw materials.

[0056] For example, it is conceivable to produce monoethylene glycol by reducing glycolic acid (HO-CH2-COOH), glyoxylic acid (OHC-COOH), oxalic acid (HOOC-COOH), glyoxal (OHC-CHO) and / or glycolaldehyde (HO-CH2-CHO) or mixtures thereof from natural sources or obtained from renewable raw materials. Within the framework of this text, these compounds are referred to here as "precursors" of monoethylene glycol, either individually or in any mixture with one another.

[0057] The reduction can be carried out here either biologically or classically chemically by hydrogenation treatment. Electrochemical reduction is also conceivable for monoethylene glycol.

[0058] It is also conceivable to use ethanol, acetaldehyde or acetic acid or mixtures thereof from natural sources or obtained from renewable raw materials, first oxidizing it to one of the components mentioned above and then reducing it. The oxidation can be carried out here either biologically or classically chemically.

[0059] In a special embodiment, ethylene or propylene can be produced partially or completely from renewable raw materials. This can be carried out, for example, by partial or complete replacement or supplementation of naphtha in a steam cracker or other decomposition unit by renewable raw materials, and then converting the ethylene or propylene thus obtained in a well-known manner to ethylene oxide or propylene oxide and then to monoethylene glycol or monopropylene glycol.

[0060] In one embodiment, the renewable raw material is biogas, i.e. a gas mixture produced by fermentation of biomass, which mainly comprises methane as a hydrocarbon. Other components of biogas are usually carbon dioxide (CO2), often also nitrogen (N2), oxygen (O2), hydrogen sulfide (H2S), hydrogen (H2) and / or ammonia (NH3). Preferably, however, these other components are separated off before utilization.

[0061] As biomass for fermentation, for example, the following can be used:

[0062] fermentable residual substances containing biomass, such as sewage sludge, biowaste or food residues;

[0063] agricultural fertilizers (manure slurry, manure);

[0064] other non-utilized plants or plant parts (intercropped crops or plant residues);

[0065] energy crops specifically grown.

[0066] Examples here are silage of corn, grass, rye and sugar beet, fodder beet, biowaste, sugar cane and manure or manure slurry from chicken, pig and cattle breeding.

[0067] In another preferred embodiment, as renewable raw material, fats and oils are preferred in this case, particularly preferred are triglycerides containing stearic acid, palmitic acid, lauric acid, oleic acid, linoleic acid and / or linolenic acid.

[0068] Particularly particularly preferred are industrially customary fats and oils, such as, for example, tallow, coconut oil, fish oil, palm kernel oil, rapeseed oil, soybean oil, turnip rape oil, peanut oil, macauba oil and palm oil, which contain oleic acid and palmitic acid as main components.

[0069] Also conceivable as substrate are fatty acids, such as stearic acid, palmitic acid, lauric acid, oleic acid, linoleic acid and / or linolenic acid, which are obtained by saponification of fats and oils. Industrially customary fatty acid mixtures are preferably tallow fatty acids, coconut oil fatty acids, fish oil fatty acids, palm kernel oil fatty acids, soybean oil fatty acids, turnip rape oil fatty acids, peanut oil fatty acids or palm oil fatty acids, which contain oleic acid and palmitic acid as main components.

[0070] In the use of oils obtained from palm, in one particular embodiment, the oil is extracted from palm, preferably from the genus Acrocomia, particularly preferably from Macaúba-Palme, in particular Acrocomia aculeata, and the oil is extracted from the pulp and / or the kernel of the palm, wherein the plant is preferably Macaúba-Palme and the oil is extracted from the Macaúba kernel, and in particular, wherein the plant is Acrocomia aculeata and the oil is extracted from the Acrocomia aculeata kernel.

[0071] The term "macauba palm" as used herein refers to a species of palm tree. Exemplary species are "Macaíba" (also known as "Boicaiuva", "Macaúva", "Coco-de-Catarro", "Coco-Baboso" and "Coco-de-Espinho"), "Acrocomia hassleri" and "Acrocomia totei". Macauba palms can grow for example up to about 15 m in height. A macauba fruit consists of pulp and a core. The term "pulp" as used herein refers to the inner fruit flesh part. The term "core" as used herein is used interchangeably with "seed" or "kernel".

[0072] Macauba palms have a high oil yield (tons / hectare / year). The term "oil yield (tons / hectare / year)" as used herein refers to the oil obtained from the plant fruit, including the pulp and the core, for example by extraction. The term refers to the oil produced per hectare. It is understood that this value refers to the oil yield achieved in a single cultivation pattern, wherein the plants are cultivated under standard conditions, which are dependent on the respective plant and are well known to the person skilled in the art. If the plants are not planted in a single cultivation pattern (for example on a pasture), the respective value for this particular planting can be reduced. Typically, the oil yield (tons / hectare / year) of oil palm is about 3.8 tons / hectare / year, of rapeseed about 0.8 tons / hectare / year, of sunflower about 0.7 tons / hectare / year and of soybean about 0.6 tons / hectare / year.

[0073] The term "single cultivation pattern" as used herein refers to the practice of planting one plant (for example macauba palm) each on a field. In the case of macauba palm, for example, about 500 to 600 palm trees per hectare can be planted. It is preferred herein that the minimum distance between the trees is about 3.5 to 4.5 meters. This number varies for example depending on the soil.

[0074] While the disadvantages of the ethylene oxide and / or ethylene glycol treatment cannot be eliminated by this process, the carbon footprint is still effectively reduced by replacing the fossil raw material by a renewable raw material, either partially or completely. The advantage of this preparation variant is that the existing production plants for the preparation of ethylene oxide or ethylene glycol do not need to be substantially modified, so that in the case of availability of ethylene based on renewable raw materials, the established and optimized processes can continue to be used.

[0075] From C ≥3 obtained

[0076] In a preferred embodiment, monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, is obtained from organic compounds having at least three carbon atoms, suitably repeating, from renewable raw materials. Preferably, these compounds have from 3 to 20, preferably from 4 to 18, particularly preferably from 5 to 16, especially particularly preferably from 6 to 14, in particular 6 carbon atoms. These compounds can be present, for example, in monomeric form or can be present in the form of biopolymers.

[0077] These compounds can be of plant or animal origin, preferably of plant origin.

[0078] Preferred are carbohydrate substrates, particularly preferably sugars in monomeric form, and also biopolymers in the form of starch, cellulose, lignin, cellulose and hemicellulose. Sugars are preferably selected from the group consisting of arabinose, fructose, galactose, glucose, lactose, mannose, maltose, sucrose and xylose. The carbohydrates can preferably be biopolymers based on one or more of these sugars.

[0079] Also conceivable as substrates are fats and oils, although less preferred, for example triglycerides comprising stearic acid, palmitic acid, lauric acid, oleic acid, linoleic acid and / or linolenic acid.

[0080] Industrially customary fats and oils are tallow, coconut oil, fish oil, palm kernel oil, rapeseed oil, soybean oil, turnip rape oil, peanut oil and palm oil, which comprise oleic acid and palmitic acid as main components.

[0081] Also conceivable as substrates are fatty acids, for example stearic acid, palmitic acid, lauric acid, oleic acid, linoleic acid and / or linolenic acid, obtained by saponification of fats and oils. Industrially customary fatty acid mixtures are preferably tallow fatty acids, coconut oil fatty acids, fish oil fatty acids, palm kernel oil fatty acids, soybean oil fatty acids, turnip rape oil fatty acids, peanut oil fatty acids or palm oil fatty acids, which comprise oleic acid and palmitic acid as main components.

[0082] In a preferred embodiment, monoethylene glycol is obtained from a carbohydrate substrate. Here, the monoethylene glycol can be obtained as the main product of the conversion of the carbohydrate substrate, as a by-product or in the form of precursors from which the monoethylene glycol can subsequently be produced, preferably in the form of a hydrogenation treatment.

[0083] The conversion of the carbohydrate substrate can preferably be the following reactions:

[0084] - hydrolysis

[0085] - fermentation

[0086] - pyrolysis

[0087] - hydrogenolysis

[0088] hydrolysis

[0089] To this end, the carbohydrate substrate is reacted with water and, optionally additionally, with at least one acid and / or at least one enzyme in one or more stages (see below "fermentation").

[0090] Thus, biopolymers, such as cellulose, hemicellulose or lignin, are often decomposed at high temperatures with water and, optionally, at least one acid into oligomeric or monomeric sugars. These sugars are then decomposed with water and, optionally, at least one acid or at least one enzyme into monoethylene glycol and / or its precursors.

[0091] The precursors can be glycolic acid (HO-CH2-COOH), glyoxylic acid (OHC-COOH), oxalic acid (HOOC-COOH), glyoxal (OHC-CHO) and / or glycolaldehyde (HO-CH2-CHO) or mixtures thereof.

[0092] fermentation

[0093] In the fermentation process, the carbohydrate substrate is incubated in the presence of at least one microorganism or at least one enzyme and monoethylene glycol and / or its precursors are obtained (see above).

[0094] To this end, it can be necessary to previously pretreat the carbohydrate substrate, for example to acidically and / or basically decompose it or to hydrolyze it at high temperatures. This is particularly meaningful for polymeric carbohydrate substrates in order to decompose them into oligomeric or monomeric carbohydrates.

[0095] For acid decomposition, the carbohydrate substrate is treated with at least one acid, preferably hydrochloric acid, phosphoric acid, sulfuric acid, sulfurous acid, carbonic acid, formic acid, acetic acid, citric acid, tartaric acid, glucuronic acid, galacturonic acid or succinic acid. Their precursors, such as hydrogen chloride, phosphorus pentoxide, pyrosulfuric acid, sulfur dioxide, sulfur trioxide or carbon dioxide, are also conceivable.

[0096] The temperature of the acid treatment is from 100°C to 270°C, preferably from 120°C to 230°C, particularly preferably from 130°C to 200°C, and the duration is from 1 minute to 300 minutes, preferably from 30 minutes to 250 minutes, particularly preferably from 60 minutes to 150 minutes.

[0097] For basic decomposition, the carbohydrate substrate is treated with at least one base, preferably calcium hydroxide (Ca(OH)2), calcium oxide (CaO), aqueous ammonia, sodium hydroxide (NaOH), sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), potassium hydroxide (KOH), potassium carbonate (K2CO3), potassium bicarbonate (KHCO3) or mixtures thereof.

[0098] The temperature of the alkaline treatment is from 50°C to 150°C, preferably from 70°C to 120°C, particularly preferably from 80°C to 100°C, for a duration of from 1 minute to 300 minutes, preferably from 30 minutes to 250 minutes, particularly preferably from 60 minutes to 150 minutes.

[0099] Preferred are carbohydrate substrates, particularly preferably sugars in monomeric form, and biopolymers in the form of starch, cellulose, lignin, cellulose and hemicellulose. The sugars are here preferably selected from the group consisting of arabinose, fructose, galactose, glucose, lactose, mannose, maltose, sucrose and xylose. The carbohydrates can preferably be biopolymers based on one or more of these sugars, preferably starch, lignin, cellulose and hemicellulose.

[0100] The microorganism can be a bacterium, a fungus or a yeast which can be genetically modified.

[0101] As the bacteria are preferably bacteria of the genus Thermoanaerobacterium, Thermoanaerobacter, Clostridium, Geobacillus, Saccharococcus, Paenibacillus, Bacillus or Anoxybacillus;Particularly preferred are selected from the group consisting of Thermoanaerobacterium thermosulfurigenes, Thermoanaerobacterium aotearoense, Thermoanaerobacterium polysaccharolyticum, Thermoanaerobacterium zeae, Thermoanaerobacterium xylanolyticum, Thermoanaerobacterium saccharolyticum, Thermoanaerobium brockii, Thermoanaerobacterium thermosaccharolyticum, Thermoanaerobacter thermohydrosulfuricus, Thermoanaerobacter ethanolicus, Thermoanaerobacter brocki, Clostridium thermocellum, Geobacillus thermoglucosidasius, Geobacillus stearothermophilus, Saccharococcus caldoxylosilyticus, Saccharococcus thermophilus, Paenibacillus campinasensis, Bacillus flavothermus, Anoxybacillus kamchatkensis and Anoxybacillus gonensis.

[0102] As fungi, preferred are selected from the group consisting of Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, Zygomycota, Glomeromycota, Ascomycota, Basidiomycota and Trichoderma reesei Rut 30.

[0103] As yeasts, preferred are selected from the group consisting of Ascomycota, Basidiomycota and Saccharomycetales.

[0104] As enzymes for hydrolyzing a carbohydrate substrate, preferably a carbohydrate substrate which has been previously decomposed by acid and / or base, cellulolytic enzymes or cellulases are preferred, in particular endoglucanases, cellobiohydrolases or beta-glucosidases, polypeptides having enhancing effect on cellulolytic enzymes, in particular GH61 polypeptides, hemicellulolytic enzymes or hemicellulases, xylanases, beta-xylosidases, acetyl xylan esterases, ferulic acid esterases, alpha-glucuronidases or alpha-L-arabinofuranosidases are particularly preferred. These enzymes and fermentation conditions are known, for example, from WO 2012 / 075963 or WO 2015 / 17869.

[0105] The fermentation is preferably carried out at a temperature of from 20°C to 60°C, particularly preferably from 25°C to 50°C, especially particularly preferably from 32°C to 50°C. The pH value during the fermentation is preferably from 3 to 7, particularly preferably from 4 to 6, especially particularly preferably from 4 to 5.

[0106] Monoethylene glycol and / or precursors thereof are often obtained as by-products, for example when ethanol is prepared from a carbohydrate substrate by fermentation, and they can be separated therefrom by distillation or non-distillation methods.

[0107] In the conventional process, glucose is fermented to ethanol, from which ethylene can be obtained by dehydration, which can be used as bio-based ethylene in the conventional preparation process for preparing monoethylene glycol via ethylene oxide. The disadvantage of this is that, when glucose is fermented to ethanol, 2 moles of CO2 are produced per mole of glucose, resulting in an atomic economy of only 67% for this method.

[0108] pyrolysis

[0109] In the pyrolysis process, a sugar, preferably a monosaccharide or disaccharide, particularly preferably a monosaccharide, particularly preferably a monomeric hexose, is heated to high temperatures and thermally decomposed. The reaction mixture obtained from the pyrolysis consists mainly of precursors of monoethylene glycol and, as by-products, C1 bodies and C3 bodies and / or C4 bodies.

[0110] Preferred monomeric hexoses are arabinose, fructose, galactose, glucose, lactose, mannose, maltose, sucrose and xylose, particularly preferred is glucose.

[0111] The sugar can be pyrolyzed in aqueous solution or alcoholic solution, preferably aqueous alcoholic solution, particularly preferably aqueous solution. As alcohols, methanol, ethanol, ethylene glycol or propylene glycol or mixtures thereof can be used.

[0112] One pyrolysis method is described, for example, in WO 2002 / 40436 A1. In this method, an aqueous solution of a sugar (preferably glucose) is pyrolyzed in a fine atom at 500°C to 600°C, preferably 520°C to 560°C, for a residence time of 0.1 seconds to 5 seconds, preferably 0.5 seconds to 2 seconds. The resulting reaction mixture is condensed to obtain ethanolaldehyde as the main product. The C1, C2, C3, and / or C4 bodies formed as byproducts are primarily so-called oxygen-containing compounds, i.e., C1, C2, C3, and / or C4 bodies with different oxidation states at the corresponding carbon atoms. These C1, C2, C3, and / or C4 bodies typically have hydroxyl, aldehyde, ketone, and / or carboxylic acid groups. Common byproducts include formaldehyde, glyoxal, hydroxyacetone (Acetol), and acetonealdehyde.

[0113] For reasons of stability of ethanolaldehyde, it is meaningful to first oxidize ethanolaldehyde to glycolic acid in the presence of oxygen and metal, preferably a noble metal, particularly palladium or platinum, and then hydrogenate the resulting reaction mixture.

[0114] The resulting reaction mixture was then hydrogenated to obtain a product mixture containing monoethylene glycol, which was then purified by distillation and / or non-distillation methods.

[0115] In the presence of hydrogen, hydrogenation can be carried out at a hydrogen pressure of 30 bar to 150 bar, preferably 40 bar to 140 bar, particularly preferably 50 bar to 120 bar, and at a temperature of 40°C to 160°C, preferably 50°C to 150°C, particularly preferably 60°C to 130°C, especially preferably 80°C to 120°C.

[0116] Supported copper, cobalt, ruthenium, palladium, platinum, or nickel are commonly used as hydrogenation catalysts. Suitable supports include carbon, alumina, silicates, titanium dioxide, zinc oxide, zirconium, or mixtures thereof, with activated carbon being the preferred support. Copper, cobalt, and nickel can also be used in the form of Raney copper, Raney cobalt, or Raney nickel.

[0117] Hydrogenation can be carried out in the gas phase or the liquid phase, preferably in the liquid phase.

[0118] Although not the preferred method, it is feasible to first purify the pyrolysis reaction mixture and then add hydrogen.

[0119] hydrogenolysis

[0120] In one embodiment of the hydrogenolysis, glucose is reduced to sorbitol, which is then converted to ethylene glycol by hydrogenolysis. Exemplary processes are described in US 6297409 B1 or US 2008 / 0228014 A1. In this case, propylene glycol and butylene glycol are usually formed as by-products, which are acceptable within certain limits, since they likewise have a lowering effect on the freezing point (see below), although they are present in the monoethylene glycol used as coolant.

[0121] In another embodiment, the carbohydrate substrate is reacted in the reactor under hydrogen with a tungsten compound and a metal having hydrogenolysis ability in group 8, 9 or 10 of the periodic table. Such a process is preferably carried out as described in WO 2016 / 114661 A1.

[0122] Possible carbohydrate substrates are also polysaccharides, oligosaccharides, disaccharides and / or monosaccharides of arabinose, fructose, galactose, glucose, lactose, mannose, maltose, sucrose and / or xylose. Use can be considered as a source, for example, of starch, fibre, lignin, cellulose, hemicellulose and sugar.

[0123] The tungsten compound preferably has an oxidation state of at least +2, particularly preferably an oxidation state of +5 or +6. The tungsten compound is then selected in an appropriate manner from the group consisting of tungstic acid (H2WO4), ammonium tungstate, ammonium metatungstate, ammonium paratungstate, a tungstate compound comprising at least one element from group 1 or 2, a metatungstate compound comprising at least one element from group 1 or 2, a paratungstate compound comprising at least one element from group 1 or 2, tungsten trioxide (WO3), a heteropoly compound of tungsten and combinations thereof.

[0124] The metal having hydrogenolysis ability in group 8, 9 or 10 of the periodic table is preferably selected from the group consisting of Cu, Fe, Ni, Co, Pt, Pd, Ru, Rh, Ir, Os and combinations thereof.

[0125] Preferably, the hydrogenolysis metal is selected from the group consisting of the noble metals Pd, Pt, Ru, Rh, Ir and combinations thereof. These metals have been found to have good yields. The metal can be present in its metallic form or as its hydride or oxide as appropriate. It is assumed that the metal oxide is reduced in the course of the reaction in the presence of hydrogen.

[0126] The metal is usually supported on a carrier, as carrier carbon, aluminium oxide, silicates, titanium dioxide, zinc oxide, zirconium or mixtures thereof are preferred.

[0127] The reaction is carried out, for example, at temperatures of from 120 to 280°C, preferably from 140 to 270°C, more preferably from 150 to 250°C, particularly preferably from 160 to 200°C, and at hydrogen pressures of from 1 to 16 MPa, preferably from 2 to 12 MPa, more preferably from 3 to 10 MPa. The residence time is generally from 5 minutes to 6 hours, preferably from 5 minutes to 2 hours.

[0128] bio-based monoethylene glycol

[0129] The monoethylene glycol obtained from renewable raw materials, preferably obtainable according to one of the above-described processes, can be characterized by determining the 14 C / 12 Cisotope ratio, preferably according to ASTM D 6866 ("Determination of the biobased content of natural range materials using radiocarbon and isotope ratio mass spectrometric analysis").

[0130] According to this test method, the 14 C / 12 Cisotope ratio of the sample is measured and compared to the 14 C / 12 Cisotope ratio in a standardized 100% biobased material. As a result, the content of the biobased fraction in the sample is obtained.

[0131] The application of ASTM-D6866 to derive the "biobased content" is based on the same theory as radiocarbon dating, but without the need to use dating equations. The analysis is performed by determining the ratio of the amount of radiocarbon ( 14 C) in the unknown sample to a modern reference standard. This index is given as a percentage in units of "pMC" (percent modern carbon). If the material to be analyzed is a mixture of modern radiocarbon and fossil carbon (containing very small amounts of radiocarbon), the obtained pMC value is directly linked to the amount of biomass material present in the sample.

[0132] A "biobased material" is an organic material whose carbon comes from CO2 that was fixed from the atmosphere by solar energy (photosynthesis) in recent times (measured on the human time scale). On land, this CO2 is taken up or fixed by plants (for example, agricultural crops or forestry plantations). In the oceans, this CO2 is bound or fixed by photosynthesis of bacteria or phytoplankton. Biobased materials therefore have a 14 C / 12 Cisotope ratio of greater than 0. In contrast, fossil materials have a 14 C / 12 Cisotope ratio of approximately 0.

[0133] A small amount of the carbon atoms in atmospheric carbon dioxide is the radioactive isotope 14C is produced when neutrons from cosmic rays collide with nitrogen atoms in the atmosphere, causing the nitrogen atom to lose a proton and thus forming carbon with an atomic mass of 14. 14 (C), the carbon atom is then oxidized to carbon dioxide. The small but measurable proportion of atmospheric carbon is... 14 Atmospheric carbon dioxide exists in the form of CO2. Atmospheric carbon dioxide is assimilated by green plants in a process called photosynthesis to produce organic molecules. Almost all life forms on Earth rely on these organic molecules produced by green plants to generate chemical energy, which enables growth and reproduction. Therefore, carbon dioxide forms in the atmosphere... 14 C ultimately becomes part of all life forms and their biological products, which are enriched in biomass and those containing... 14 C is found in organisms that consume biomass. In contrast, carbon from fossil sources (especially fuels) does not possess the characteristic renewable organic molecules derived from atmospheric carbon dioxide. 14 C: 12 C ratio.

[0134] The monoethylene glycol used in the coolant of this invention has a bio-based content, in accordance with ASTM-D6866. 14 C: 12 The C ratio is measured in the form of greater than 0%, preferably at least 1%, particularly preferably at least 5%, especially preferably at least 10%, particularly at least 20%, and especially at least 25%.

[0135] Advantageously, the bio-based content can be at least 30%, preferably at least 40%, particularly preferably at least 50%, especially preferably at least 66%, particularly at least 75%, and especially at least 85%.

[0136] When the proportion is at least 90%, preferably at least 95%, particularly preferably at least 98%, or even 100%, it can be called a monoethylene glycol with significant advantages or completely bio-based.

[0137] The C-14 content of a material can be determined by measuring the decay rate of C-14 in the material using a liquid scintillation method. Such raw materials with a C-14 content indicating a radioactive decay rate of not less than 1.5 dpm / gC (decay rate per gram of carbon per minute), preferably 2 dpm / gC, more preferably 2.5 dpm / gC, and even more preferably 5 dpm / gC, are preferably considered to be obtained from renewable raw materials.

[0138] The monoethylene glycol used in the coolant can be obtained entirely from renewable raw materials, or it can consist of a mixture of monoethylene glycol from renewable and fossil sources.

[0139] It should be emphasized that, especially when monoethylene glycol is constructed from a C1 source (as described above), the amount of...14 C: 12 C than from C1 sources (i.e. CO and / or CO2, in particular CO2) alone. 14 C: 12 C than from C1 sources (i.e. CO and / or CO2, in particular CO2) alone.

[0140] by-product range

[0141] The advantage of the monoethylene glycol or monopropylene glycol obtained from renewable raw materials is that it has a lower content of higher oligomers than the product obtained from the hydrolysis of ethylene oxide or propylene oxide.

[0142] In general, the proportion of higher oligomers, i.e. preferably diethylene glycol, triethylene glycol, tetraethylene glycol and / or dipropylene glycol, tripropylene glycol, tetrapropylene glycol (total) in the monoethylene glycol or monopropylene glycol thus obtained is less than 5% by weight, preferably less than 3% by weight, particularly preferably less than 2% by weight, very particularly preferably less than 1% by weight, in particular less than 0.5% by weight.

[0143] Preferably, the proportion of the higher oligomers, in particular diethylene glycol, is not more than 0.4% by weight, particularly preferably not more than 0.2% by weight, very particularly preferably not more than 0.15% by weight, in particular not more than 0.1% by weight, and in particular not more than 0.05% by weight.

[0144] Since these oligomers have a surfactant effect, as described above, the monoethylene glycol or monopropylene glycol from renewable raw materials exhibits a lower tendency to foam.

[0145] Depending on the process shown for the preparation of the monoethylene glycol or monopropylene glycol from renewable raw materials, the monoethylene glycol or monopropylene glycol thus obtained can have other by-products.

[0146] In this way, the monoethylene glycol thus obtained can for example comprise at least one of the components mentioned:

[0147] - diethylene glycol in an amount of 0.01 to 0.25% by weight, preferably 0.02 to 0.2% by weight, particularly preferably 0.03 to 0.15% by weight, and especially particularly preferably 0.03 to 0.1% by weight,

[0148] - 1,2-propanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0149] - 1,3-propanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0150] - 1,2-butanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0151] - 2,3-butanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight.

[0152] A low content of diethylene glycol results in a lower foaming of the coolant.

[0153] Thus, the monopropylene glycol thus obtained can for example comprise at least one of the specified components:

[0154] - 1,2-ethanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0155] - 1,3-propanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0156] - 1,2-butanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight,

[0157] - 2,3-butanediol in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight, and especially particularly preferably 0.25 to 1% by weight.

[0158] These diol compounds, which can be obtained as by-products, also act as components for lowering the freezing point themselves, and thus can be retained in the monoethylene glycol or monopropylene glycol in the specified amounts without significantly impairing the effect of lowering the freezing point. In some cases, these diol compounds even have a higher heat load capacity, heat capacity or thermal conductivity than monoethylene glycol or monopropylene glycol, so that they show advantages under the conditions in the cooling circuit.

[0159] Furthermore, the diol compounds with secondary hydroxyl groups, i.e. 1,2-propanediol, 1,2-butanediol and 2,3-butanediol, have a greater oxidative stability than 1,2-ethanediol. From 1,2-ethanediol, glycolic acid is formed by oxidation, which is corrosive in cooling systems. The formation of similar acids is more difficult in the case of 1,2-propanediol and 1,2-butanediol under the conditions in the cooling circuit and does not occur significantly in the case of 2,3-butanediol.

[0160] In addition, they can also contain ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol and / or isobutanol, each in an amount of not more than 1% by weight, preferably not more than 0.75% by weight, particularly preferably not more than 0.5% by weight, especially particularly preferably not more than 0.25% by weight, in particular not more than 0.15% by weight.

[0161] In addition, they can also contain oxidation products, i.e. glycolic acid (HO-CH2-COOH), glyoxylic acid (OHC-COOH), oxalic acid (HOOC-COOH), glyoxal (OHC-CHO) and / or ethanol aldehyde (HO-CH2-CHO) in the case of monoethylene glycol or similar products in the case of monopropylene glycol, each in an amount of not more than 2% by weight, preferably not more than 1.5% by weight, particularly preferably not more than 1% by weight, especially particularly preferably not more than 0.75% by weight, in particular not more than 0.5% by weight.

[0162] The process described above for the preparation from renewable raw materials has the advantage that the boiling points of the mentioned by-products are lower than those of the oligomers, which leads to lower energy requirements for the preparation process.

[0163] coolants

[0164] The subject matter of the application is therefore a coolant which comprises monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, as a freezing point lowering diol component, which is obtained from renewable raw materials.

[0165] This is in particular a coolant which comprises

[0166] - at least 40% by weight of water (A)

[0167] - at least 30 % by weight of alkylene glycols, alkylene glycol monoalkyl ethers and glycerol (B),

[0168] as inhibitors (C)

[0169] - (C1 ) optionally at least one inorganic compound selected from the group consisting of silicates, borates, nitrates, molybdates and phosphates

[0170] - (C2a) optionally benzoic acid as aromatic monocarboxylic acid

[0171] - (C2b) optionally at least one aliphatic monocarboxylic acid,

[0172] - (C3) optionally at least one organic dicarboxylic acid having 4 to 20 carbon atoms

[0173] - (C4) at least one azole compound, preferably at least one triazole compound

[0174] - (D) optionally at least one inorganic base

[0175] - (E) at least one further constituent selected from the group consisting of hard water stabilizers, antifoams, dyes and bitter substances

[0176] characterized in that

[0177] Component (B) comprises at least in part monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, which is at least in part obtained from renewable raw materials.

[0178] components

[0179] (a) water

[0180] The water used within the framework of the present application should be neutral, having a pH value of around 7, here it can be deionized or distilled water, but this is not mandatorily necessary. In order to also make it possible to use hard water, the composition of the present application usually comprises at least one hard water stabilizer (see below).

[0181] (b) alkylene glycols, alkylene glycol monoalkyl ethers and glycerol

[0182] Component (B) causes the main freezing point depression in the coolant.

[0183] According to the present application, component (B) comprises at least in part monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, which is at least in part obtained from renewable raw materials.

[0184] In addition to such monoethylene glycol and / or monopropylene glycol obtained from renewable raw materials, component (B) can also comprise other alkylene glycols, alkylene glycol monoalkyl ethers or glycerol which are not monoethylene glycol and / or monopropylene glycol obtained from renewable raw materials.

[0185] In a preferred embodiment of the application, however, component (B) consists exclusively of monoethylene glycol and / or monopropylene glycol, preferably of monoethylene glycol.

[0186] In a particularly preferred embodiment, at least 10 %, preferably at least 20 %, particularly preferably at least 30 %, especially particularly preferably at least 40 %, in particular at least 50 %, especially at least 66 % of the monoethylene glycol and / or monopropylene glycol, preferably of the monoethylene glycol, used is obtained from renewable raw materials.

[0187] Advantageously, this proportion can be at least 75 %, preferably at least 85 %, particularly preferably at least 90 %, especially particularly preferably at least 95 %, in particular at least 98 %, and especially even 100 %.

[0188] The other individual which is not monoethylene glycol and / or monopropylene glycol obtained from renewable raw materials as component (B) is 1,2-ethanediol, 1,2-propanediol or more rarely 1,3-propanediol, preferably 1,2-ethanediol or 1,2-propanediol, particularly preferably 1,2-ethanediol, especially particularly preferably 1,2-ethanediol, in monomeric to tetrameric form, and mixtures thereof.

[0189] The alkylene glycol monoalkyl ether is a mono Ci-C4-alkyl ether of the above-mentioned alkylene glycols, preferably a monomethyl ether, monoethyl ether or n-butyl ether, particularly preferably a monomethyl ether or n-butyl ether, especially particularly preferably a monomethyl ether.

[0190] Furthermore, glycerol or glycerol oligomers are possible components (B).

[0191] Preferred alkylene glycol components or derivatives are in particular monoethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol and mixtures thereof; furthermore, however, also monopropylene glycol, dipropylene glycol and mixtures thereof, individually or in mixtures; polyethylene glycol; glycol ethers, such as, for example, monoethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetraethylene glycol monomethyl ether, monoethylene glycol monoethyl ether, diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monoethyl ether, monoethylene glycol monon-butyl ether, diethylene glycol monon-butyl ether, triethylene glycol monon-butyl ether, tetraethylene glycol monon-butyl ether, or glycerol.

[0192] It is particularly preferred to use monoethylene glycol alone or as a main component in a mixture with other alkylene glycols or alkylene glycol derivatives, the main component meaning that the content of the mixture is greater than 50% by weight, in particular greater than 80% by weight, especially greater than 95% by weight.

[0193] inhibitors (c)

[0194] The inhibitors (C) act as corrosion inhibitors for metals, for example ferrous materials, aluminum, non-ferrous metals or solders.

[0195] The composition according to the application comprises

[0196] (C1 ) optionally at least one inorganic compound selected from the group consisting of silicates, borates, nitrates, molybdates and phosphates and organic silicates

[0197] (C2a) optionally benzoic acid as an aromatic monocarboxylic acid

[0198] (C2b) optionally at least one aliphatic monocarboxylic acid

[0199] (C3) optionally at least one organic dicarboxylic acid having 4 to 20 carbon atoms

[0200] (C4) at least one azole, preferably at least one triazole compound.

[0201] inorganic inhibitors (c1)

[0202] The inorganic inhibitors (C1 ) are silicates, borates, nitrates, molybdates or phosphates, or mixtures thereof in the form of their free acids or salts, in particular alkali metal salts, particularly preferably sodium or potassium salts. Which form (protonated or salt) they are present in the composition, superconcentrate, concentrate or coolant depends on the respective pK value of the compound and the composition as well as the pH value of the respective environment, which is determined by the amount of base (D). s

[0203] The inorganic silicates act primarily as inhibitors for aluminum corrosion, usually in the form of alkali metal salts or, more rarely, magnesium, calcium or aluminum salts, preferably in the form of sodium or potassium salts.

[0204] The silicates are preferably selected from the group consisting of orthosilicates (SiO4 4- ), metasilicates (SiO3 2- ) and disilicates (Si2O7 6- ), particularly preferably metasilicates (SiO3 2- ​) and especially particularly preferably sodium metasilicate (Na2SiO3) or potassium metasilicate (K2SiO3), in particular sodium metasilicate (Na2SiO3).

[0205] If the solid composition of the present application comprises at least one inorganic silicate or one organic silicate ester, in a preferred embodiment at least one silicophosphonate is additionally added besides the silicate, as described for the silicate ester in EP 4015596 or WO 2022 / 043303.

[0206] Preferably, the silicophosphonate is a compound of the following general formula:

[0207]

[0208] wherein

[0209] R 5 is a divalent organic radical, preferably a 1,w-alkylene radical having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, particularly preferably methylene, 1,2-ethylene, 1,2- propylene, 1,3-propylene or 1,4-butylene, especially particularly preferably 1,2-ethylene or 1,3- propylene, in particular 1,2-ethylene,

[0210] R 6 are each independently hydrogen, Ci to C4-alkyl or hydroxy-C2-C4-alkyl, preferably hydrogen, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl or t-butyl, 2-hydroxyethyl or 2-hydroxypropyl, particularly preferably hydrogen, methyl, ethyl or propyl,

[0211] and R 7 is Ci to C4-alkyl, preferably methyl, ethyl, n-propyl or n-butyl, particularly preferably methyl, ethyl or n-butyl, especially particularly preferably methyl or ethyl, in particular methyl.

[0212] The silicophosphonate can be used in the form of the free acid or an alkali metal salt, preferably in the form of the sodium or potassium salt, particularly preferably in the form of the sodium salt.

[0213] The borate is preferably used in the form of sodium tetraborate (borax) or potassium tetraborate, particularly preferably in the form of sodium tetraborate.

[0214] The nitrate is used in the form of an alkali metal or alkaline earth metal nitrate, preferably in the form of sodium nitrate, potassium nitrate or magnesium nitrate, preferably in the form of sodium nitrate or potassium nitrate, particularly preferably in the form of sodium nitrate.

[0215] The phosphate is used in the form of the free acid (H3PO4), hydrogen phosphate, dihydrogen phosphate or phosphate, preferably in the form of the sodium or potassium salt.

[0216] It is also conceivable to use corresponding di- or tri- or oligophosphates, but preferably monomeric phosphates are used.

[0217] Preferably, the phosphoric acid is used in the form of the free acid (H3PO4), disodium hydrogen phosphate or trisodium phosphate.

[0218] Orthosilicates are compounds of the following formula

[0219] Si(OR 1 )4

[0220] wherein

[0221] R 1 is an organic substituent having 1 to 6 carbon atoms, such as straight-chain or branched, preferably straight-chain alkyl substituents having 1 to 6 carbon atoms or aromatic substituents having 6 carbon atoms, particularly preferably alkyl substituents having 1 to 4 carbon atoms, very particularly preferably alkyl substituents having 1 or 2 carbon atoms.

[0222] Alkoxyalkylsilanes are less preferred, the alkoxy substituents and the alkyl groups both include straight-chain or branched, preferably straight-chain alkyl substituents having 1 to 6 carbon atoms, particularly preferably alkyl substituents having 1 to 4 carbon atoms, very particularly preferably alkyl substituents having 1 or 2 carbon atoms.

[0223] Typical examples of compounds (D) are tetraalkoxysilanes, preferably tetramethoxysilane and tetraethoxysilane, and alkoxyalkylsilanes, preferably triethoxymethylsilane, diethoxydimethylsilane, ethoxytrimethylsilane, trimethoxymethylsilane, dimethoxydimethylsilane and methoxytrimethylsilane. Tetraalkoxysilanes are preferred, particularly preferably tetramethoxysilane and tetraethoxysilane, very particularly preferably tetraethoxysilane.

[0224] Preferably, component (C1) is at least one compound selected from the group consisting of silicates, borates, nitrates or phosphates, particularly preferably at least one compound selected from the group consisting of silicates, nitrates or phosphates.

[0225] (c2a) aromatic monocarboxylic acids

[0226] The optional aromatic monocarboxylic acid is preferably benzoic acid, which can be used in the form of the free acid or particularly preferably in the form of an alkali metal salt thereof, very particularly preferably in the form of sodium benzoate.

[0227] In a preferred embodiment of the application, no aromatic monocarboxylic acid is present.

[0228] (c2b) aliphatic monocarboxylic acids

[0229] Aliphatic monocarboxylic acids are organic aliphatic alkane or alkene carboxylic acids. They are used as corrosion inhibitors for ferrous materials in coolants (provided they are sufficiently water-soluble). Preferably, such aliphatic monocarboxylic acids have 5 to 12 carbon atoms, particularly preferably 6 to 10 carbon atoms, and very particularly preferably 8, 9 or 10 carbon atoms.

[0230] Typical such monocarboxylic acids are valeric acid, 2,2-dimethylpropionic acid, caproic acid, 2,2-dimethylbutyric acid, caprylic acid, 2-ethylhexanoic acid, n- nonanoic acid, iso-nonoanoic acid, capric acid, undecanoic acid and lauric acid, and isomer mixtures thereof, particularly 2-ethylhexanoic acid, n-nonanoic acid and iso- nonanoic acid isomer mixtures.

[0231] However, this represents a possible embodiment in which the aliphatic monocarboxylic acid is used in the form of an alkali metal salt thereof, preferably in the form of a lithium, sodium or potassium salt thereof, particularly preferably in the form of a sodium or potassium salt thereof, instead of the free acid.

[0232] (c3) organic dicarboxylic acids having 4 to 20 carbon atoms

[0233] Organic dicarboxylic acids having 4 to 20 carbon atoms are linear or branched alkanedicarboxylic acids, preferably linear alkanedicarboxylic acids or alkenedicarboxylic acids, particularly preferably linear alkanedicarboxylic acids, particularly preferably having 5 to 14 carbon atoms, and very particularly preferably having 6 to 12 carbon atoms.

[0234] Preferably, the dicarboxylic acid (C3) is selected from the group consisting of succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, pimelic acid (heptane diacid), azelaic acid (nonane diacid), sebacic acid (decane diacid), undecanedioic acid, dodecanedioic acid, and alkyl and alkenyl succinic and glutaric acids such as 2-methylbutanedioic acid, 2-ethyl-3-methylbutanedioic acid, 2-ethylglutaric acid, 2-dodecylbutanedioic acid, 2-dodecenylbutanedioic acid, 2-phenylbutanedioic acid, 2-(p-methylphenyl)butanedioic acid, 2,2-dimethylbutanedioic acid, 2,3,4-trimethylglutaric acid, 2,2,3-trimethylglutaric acid, pentenedioic acid (2-pentenedioic acid), itaconic acid, 2-hexenedioic acid, 3-hexenedioic acid, 5-methyl-2-hexenedioic acid and 2,3-dimethyl-2-pentenedioic acid.

[0235] Among these, dicarboxylic acids having 6 to 12 carbon atoms are preferred, wherein particularly preferably alkanedicarboxylic acids having 6 to 12 carbon atoms are preferred, and very particularly preferably linear alkanedicarboxylic acids having 6 to 12 carbon atoms are preferred.

[0236] In particular, as dicarboxylic acid (D3), adipic acid, sebacic acid, azelaic acid and dodecanedioic acid are preferred.

[0237] (c4) azole compounds

[0238] Within the framework of the present document, azole derivatives (C4) are five-membered heterocyclic compounds having 2 or 3 heteroatoms selected from the group of nitrogen and sulfur, which can be free of sulfur atoms in the ring structure or contain at most one embedded sulfur atom, and optionally carry an aromatic or saturated six-membered fused ring.

[0239] These five-membered heterocyclic compounds (azole derivatives) generally contain two nitrogen atoms and no sulfur atom; three nitrogen atoms and no sulfur atom; or one nitrogen atom and one sulfur atom as heteroatoms.

[0240] Preferred groups of the above-mentioned azole derivatives are fused imidazoles and fused 1,2,3-triazole compounds of the following general formula:

[0241] (III)

[0242] or (IV)

[0243] wherein the variables

[0244] R means hydrogen or Ci to C 10 alkyl, in particular methyl or ethyl, and

[0245] The variable X denotes a nitrogen atom or a C-H group.

[0246] Typical and preferred examples of azole derivatives of the general formula (III) are benzimidazole (X = C-H, R = H), benzotriazole (X = N, R = H) and methylbenzotriazole (Tolyltriazol) (X = N, R = CH3). A typical example of azole derivatives of the general formula (IV) is hydrogenated 1,2,3-methylbenzotriazole (Tolyltriazol) (X = N, R = CH3).

[0247] Another preferred group of the mentioned azole derivatives are benzothiazole compounds of the general formula (V)

[0248]

[0249] wherein

[0250] The variable R has the above-mentioned meaning, and

[0251] The variable R' denotes hydrogen, Ci to C 10 alkyl, in particular methyl or ethyl, or in particular a mercapto group (-SH). It is conceivable, although less preferred, that R' can also be a carboxyalkyl group of the general formula -(C m H 2m )-COOR'' with m being an integer from 1 to 4 and R'' representing hydrogen, Ci-C 10 alkyl, in particular methyl or ethyl, or C6-C12 Examples for this are (2-benzothiazylthio)acetic acid, (2-benzothiazylthio)acetate, 3-(2-benzothiazylthio)propionic acid, or 3-(2-benzothiazylthio)propionate. If these compounds are used as acids, they do not belong to the excluded carboxylic acids of the present application. A typical example of an azole derivative of the general formula (V) is 2-mercaptobenzothiazole.

[0252] Furthermore non-fused azole derivatives of the general formula (VI) are

[0253] (VI)

[0254] wherein the variables

[0255] X and Y together designate two nitrogen atoms or

[0256] one nitrogen atom and one C-H group,

[0257] for example 1 H-1,2,4-triazole (X=Y=N) or preferably imidazole (X=N, Y=C-H).

[0258] Particularly preferred as azole derivatives for the present application are benzimidazole, benzotriazole, methylbenzotriazole, hydrogenated methylbenzotriazole or mixtures thereof, in particular benzotriazole or methylbenzotriazole, especially methylbenzotriazole.

[0259] The azole derivatives mentioned above are commercially available or can be prepared by conventional methods. Hydrogenated benzotriazoles such as hydrogenated methylbenzotriazole are likewise obtainable according to DE-A 1 948 794 and are also commercially available.

[0260] Preferably, the azole is selected from the group consisting of benzotriazole, methylbenzotriazole, (2-benzothiazylthio)acetic acid, 3-(2-benzothiazylthio)propionic acid and 2-mercaptobenzothiazole.

[0261] (d) inorganic bases

[0262] The pH value of the antifreeze at the end user is usually in the range from 4 to 11.5, preferably from 5 to 10, in particular from 6 to 9.

[0263] To set the pH value, at least one inorganic base is added at any stage in the process of preparing the coolant from the concentrated precursor (D). Here, the at least one inorganic base can be contained in the composition of the application, in the superconcentrate or in the concentrate, or added when the superconcentrate is prepared by mixing the composition of the application with components (A) and / or (B), or added when the concentrate is prepared by mixing the superconcentrate with components (A) and / or (B), or added when the coolant is prepared by mixing the concentrate with components (A) and / or (B).

[0264] The composition of the application thus optionally contains an amount of inorganic base which, upon corresponding dilution, sets the desired pH value in the coolant. The composition according to the application for this purpose preferably contains an alkali metal hydroxide, particularly preferably lithium, sodium or potassium hydroxide in solid form, if appropriate also in the form of an aqueous solution of lithium, sodium or potassium hydroxide.

[0265] Less preferred are carbonates or bicarbonates of lithium, sodium or potassium.

[0266] The preferred alkali metals are sodium and potassium.

[0267] In a preferred embodiment, at least part of the inorganic base, preferably all of the required inorganic base, is already contained in the composition of the application. This has the advantage on the one hand that no further addition of base is necessary at any subsequent preparation stage, thus eliminating the risk of mis-dosing, and on the other hand that the acid added thereby exists in the form of its usually more readily crystallizable alkali metal salt, which facilitates the formulation of the solid composition of the application as a solid.

[0268] (e) further constituents selected from the group consisting of water hardness stabilizers, antifoams, dyes and bitter substances

[0269] As further customary auxiliary means, the composition of the application can also contain a usually small amount of antifoam (typically in an amount of 0.003 to 0.008% by weight in the finished dilution coolant), and, for hygiene and safety reasons in the event of ingestion, a bitter substance (e.g. of the denatonium benzoate type) and a dye.

[0270] Furthermore, the composition can contain one or more water hardness stabilizers based on polyacrylic acid, polymaleic acid, acrylic acid-maleic acid copolymer, polyvinylpyrrolidone, polyvinylimidazole, vinylpyrrolidone-vinylimidazole copolymer and / or copolymers of an unsaturated carboxylic acid and an olefin. The proportion in the composition is so chosen that, upon corresponding dilution, the amount in the finished dilution coolant is at most 1% by weight.

[0271] concentrates, super concentrates

[0272] To reduce the transport volume, high water content coolants are usually not delivered, but concentrates are sold, in which the water is removed or greatly reduced. The end user prepares the concentrates to coolants by adding water.

[0273] To further reduce the transport volume, so-called super concentrates are often prepared centrally, in which not only the water, but also the glycol component is additionally removed or greatly reduced. From these super concentrates, the concentrates are then prepared by the formulator at the regional level by mixing glycols.

[0274] The core of the present application is that the glycols used for mixing meet the requirements of the present application, i.e. are at least partially obtained from renewable raw materials.

[0275] A further subject of the present application is a coolant concentrate, comprising:

[0276] - not more than 15% by weight, preferably not more than 10% by weight, particularly preferably not more than 5% by weight of water (A)

[0277] - at least one alkylene glycol, alkylene glycol monoalkyl ether or glycerol (B)

[0278] as an inhibitor (C)

[0279] - (C1 ) optionally at least one inorganic compound selected from the group consisting of silicates, borates, nitrates, molybdates and phosphates

[0280] - (C2a) optionally benzoic acid as an aromatic monocarboxylic acid

[0281] - (C2b) optionally at least one aliphatic monocarboxylic acid,

[0282] - (C3) optionally at least one organic dicarboxylic acid having 4 to 20 carbon atoms

[0283] - (C4) at least one azole compound, preferably at least one triazole compound

[0284] - (D) optionally at least one inorganic base

[0285] - (E) at least one further constituent selected from the group consisting of a hard water stabilizer, an antifoam, a dye and a bitter substance

[0286] wherein

[0287] Component (B) comprises at least partially monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, which is at least partially obtained from renewable raw materials.

[0288] A further subject of the present application is a coolant super concentrate, comprising:

[0289] - not more than 15 % by weight, preferably not more than 10 % by weight, particularly preferably not more than 5 % by weight of water (A)

[0290] - at least one alkylene glycol, alkylene glycol monoalkyl ether or glycerol (B)

[0291] as an inhibitor (C)

[0292] - (C1 ) optionally at least one inorganic compound selected from the group consisting of silicates, borates, nitrates, molybdates and phosphates

[0293] - (C2a) optionally benzoic acid as an aromatic monocarboxylic acid

[0294] - (C2b) optionally at least one aliphatic monocarboxylic acid,

[0295] - (C3) optionally at least one organic dicarboxylic acid having 4 to 20 carbon atoms

[0296] - (C4) at least one azole, preferably at least one triazole compound

[0297] - (D) optionally at least one inorganic base

[0298] - (E) at least one further constituent selected from the group consisting of a water hardness stabilizer, an antifoam, a dye and a bitter substance

[0299] wherein

[0300] Component (B) comprises at least in part monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, which is at least in part obtained from renewable raw materials.

[0301] A further subject matter of the present application is a process for preparing the above-mentioned coolant concentrate from the above-mentioned coolant superconcentrate, in which one mixes the coolant superconcentrate with a corresponding amount of at least one alkylene glycol, alkylene glycol monoalkyl ether or glycerol (B), with the proviso that one uses at least in part monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, as component (B), which is at least in part obtained from renewable raw materials.

[0302] sustainability indicators

[0303] A further subject of the present application is a method for reducing emissions, such as nitrogen oxide and sulfur oxide emissions, in particular carbon dioxide emissions, preferably as determined in terms of carbon footprint, ecological balance or according to DIN EN ISO 14021, DIN EN ISO 14067, here in particular the 2019-02 version, DIN EN ISO 14044, here in particular the 2006+A1 :2018 version and / or DIN EN ISO 14040, here in particular the 2009-11 version, in the production of an alkylene glycol-containing coolant, wherein at least partly monoethylene glycol and / or monopropylene glycol, preferably monoethylene glycol, is used in the production of the coolant, which is at least partly obtained from renewable raw materials.

[0304] For determining the ecological balance, here preferably DIN EN ISO 14040, here in particular the 2009-11 version, and / or DIN EN ISO 14044, here in particular the 2006+A1 :2018 version, are used as a basis.

[0305] For determining the carbon footprint, here preferably DIN EN ISO 14067, here in particular the 2019-02 version, is used as a basis.

[0306] By producing monoethylene glycol and / or monopropylene glycol from renewable raw materials, the aforementioned disadvantages are avoided, so that the monoethylene glycol and / or monopropylene glycol thus obtained has a more favorable ecological balance and / or a lower carbon footprint.

[0307] Even if the CO2 used comes entirely from fossil materials, but is captured and used for producing monoethylene glycol, i.e. from a carbon capture and utilization (CCU) process, the proportion of fossil carbon can be 100% and the proportion of biobased carbon can be 0%. Nevertheless, the monoethylene glycol obtained in this way still falls within the scope of the present application, since it binds CO2 and reduces the carbon footprint of the monoethylene glycol, due to the fact that the product acts as a carbon sink, in particular in that it takes up or prevents the emission of CO2 in fossil form from the atmosphere and instead utilizes it.

[0308] In the above case, in which the monoethylene glycol is produced entirely or partly from ethylene oxide or ethylene from renewable raw materials, for example from the dehydration of ethanol produced from glucose, the advantage of the method according to the application is not in avoiding the handling of ethylene oxide, but in that at least partly renewable raw materials are used in the production of the monoethylene glycol in this method, so that the production still has a more favorable ecological balance and / or a lower carbon footprint compared to the production from fossil raw materials.

Claims

1. A coolant comprising - At least 40% by weight water (A) - At least 30% by weight of alkylene glycols, alkylene glycol monoalkyl ethers and glycerol (B). As an inhibitor (C) - (C1) Optionally selected from at least one inorganic compound consisting of silicates, borates, nitrates, molybdates and phosphates. -(C2a) benzoic acid, optionally an aromatic monocarboxylic acid -(C2b) optionally at least one aliphatic monocarboxylic acid, - (C3) Optionally at least one organic dicarboxylic acid having 4 to 20 carbon atoms - (C4) At least one azole compound, preferably at least one triazole compound - (D) Optionally at least one inorganic base - (E) At least one other component, selected from the group consisting of hard water stabilizers, defoamers, dyes, and bitter substances. Its features are, Component (B) comprises at least partially monoethylene glycol and / or 1,2-propanediol, preferably monoethylene glycol, wherein the monoethylene glycol and / or 1,2-propanediol is at least partially derived from renewable feedstocks, wherein the bio-based content of the monoethylene glycol and / or 1,2-propanediol, preferably monoethylene glycol, used is determined according to ASTM-D 6866. 14 C / 12 The C isotope ratio is measured in the form of greater than 0%, preferably at least 1%, particularly preferably at least 5%, especially preferably at least 10%, particularly at least 20%, and especially at least 25%.

2. The coolant according to claim 1, characterized in that, The component comprises (B) monoethylene glycol and / or 1,2-propanediol, preferably monoethylene glycol, which is obtained at least in part by conversion of carbon dioxide (CO2) and carbon monoxide (CO) by genetically modified microorganisms and / or enzymes.

3. The coolant according to claim 1, characterized in that, The component (B) used contains monoethylene glycol, which is obtained at least in part by reducing glycolic acid (HO-CH2-COOH), glyoxylic acid (OHC-COOH), oxalic acid (HOOC-COOH), glyoxal (OHC-CHO) and / or glycolaldehyde (HO-CH2-CHO) or mixtures thereof derived from natural or renewable raw materials.

4. The coolant according to claim 1, characterized in that, The component (B) comprises ethylene glycol and / or 1,2-propanediol, preferably ethylene glycol, which is at least partially obtained from ethylene or propylene, which is produced from the decomposition of renewable feedstocks, subsequently converted into ethylene oxide or propylene oxide, and subsequently converted into ethylene glycol or 1,2-propanediol.

5. The coolant according to claim 1, characterized in that, The component (B) used comprises monoethylene glycol and / or 1,2-propanediol, preferably monoethylene glycol, which is obtained by decomposing organic compounds having at least three carbon atoms, and repeating where appropriate, from renewable feedstock.

6. The coolant according to claim 5, characterized in that, The organic compounds of renewable raw materials are selected from the group consisting of sugars, starch, fiber, lignin, cellulose and hemicellulose.

7. The coolant according to claim 5, characterized in that, The organic compounds of renewable raw materials are monomers or biopolymers based on arabinose, fructose, galactose, glucose, lactose, mannose, maltose, sucrose and / or xylose.

8. The coolant according to claim 5, characterized in that, Carbohydrate substrates are converted into monoethylene glycol and / or its precursors via hydrolysis, fermentation, pyrolysis or hydrogenolysis, selected from the group consisting of glycolic acid (HO-CH2-COOH), glyoxylic acid (OHC-COOH), oxalic acid (HOOC-COOH), glyoxal (OHC-CHO) and / or glycolaldehyde (HO-CH2-CHO) or mixtures thereof, and any precursors present are converted into monoethylene glycol via reduction.

9. The coolant according to any one of the preceding claims, characterized in that, The bio-based content of the monoethylene glycol and / or 1,2-propanediol used, preferably monoethylene glycol, shall be determined according to ASTM D 6866. 14 C / 12 The C isotope ratio, as measured in the form of a carbon isotope ratio, is at least 30%, preferably at least 40%, particularly preferably at least 50%, especially preferably at least 66%, particularly at least 75%, and especially at least 85%.

10. The coolant according to any one of the preceding claims, characterized in that, Component (B) obtained from renewable feedstock is monoethylene glycol, which contains at least one of the specified components: - The amount of diethylene glycol is 0.01% to 0.25% by weight, preferably 0.02% to 0.2% by weight, particularly preferably 0.03% to 0.15% by weight, and especially particularly preferably 0.03% to 0.1% by weight. - The amount of 1,2-propanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 1,3-propanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 1,2-butanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 2,3-butanediol is 0.05% to 5% by weight, preferably 0.1% to 3% by weight, particularly preferably 0.2% to 2% by weight, and especially preferably 0.25% to 1% by weight.

11. The coolant according to any one of claims 1 to 9, characterized in that, Component (B) obtained from renewable feedstock is 1,2-propanediol, which contains at least one of the specified components: - The amount of 1,2-ethylene glycol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially particularly preferably from 0.25% to 1% by weight. - The amount of 1,3-propanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 1,2-butanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 2,3-butanediol is 0.05% to 5% by weight, preferably 0.1% to 3% by weight, particularly preferably 0.2% to 2% by weight, and especially preferably 0.25% to 1% by weight.

12. Use of monoethylene glycol and / or 1,2-propanediol, preferably monoethylene glycol, in a coolant, wherein the monoethylene glycol and / or 1,2-propanediol are at least partially obtained from renewable feedstocks.

13. The use of monoethylene glycol in a coolant according to claim 12, wherein the monoethylene glycol has a diethylene glycol content of 0.01% to 0.25% by weight to reduce foaming.

14. The use of monoethylene glycol in a coolant according to claim 12, wherein the monoethylene glycol has the following content: - The amount of diethylene glycol is 0.01% to 0.25% by weight, preferably 0.02% to 0.2% by weight, particularly preferably 0.03% to 0.15% by weight, and especially particularly preferably 0.03% to 0.1% by weight. - The amount of 1,2-propanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 1,3-propanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 1,2-butanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. - The amount of 2,3-butanediol is from 0.05% to 5% by weight, preferably from 0.1% to 3% by weight, particularly preferably from 0.2% to 2% by weight, and especially preferably from 0.25% to 1% by weight. To improve the heat load capacity, heat capacity, thermal conductivity and / or oxidative stability of components that lower the freezing point.

15. A method for reducing emissions, such as nitrogen oxides and sulfur oxides, particularly carbon dioxide emissions, during the preparation of a coolant containing alkylene glycols, preferably as a measure of carbon footprint, ecological balance, or as determined according to DIN EN ISO 14021, DIN EN ISO 14067, specifically version 2019-02, DIN EN ISO 14044, specifically version 2006+A1:2018, and / or DIN EN ISO 14040, specifically version 2009-11, wherein at least partially ethylene glycol and / or 1,2-propanediol, preferably ethylene glycol, are used in the preparation of the coolant, wherein the ethylene glycol and / or 1,2-propanediol are at least partially obtained from renewable feedstocks.

Images