EP3681851A1

EP3681851A1 - Process for the production of humic substances from biomass such as wood, bark, cereal straw, leaves, herbaceous plants and also tree fungi, sewage sludge and other organic wastes

Info

Publication number: EP3681851A1
Application number: EP18749775.5A
Authority: EP
Inventors: Ernst Schaltegger; Nikolaus Foidl
Original assignee: Schaltegger Projektplanungen
Current assignee: Schaltegger Projektplanungen
Priority date: 2017-09-13
Filing date: 2018-07-31
Publication date: 2020-07-22
Also published as: BR112020002020A2; JP2020537623A; WO2019052738A1; US20210130503A1; CA3072258A1; AU2018331216A1

Abstract

The invention relates to a process for the chemical synthesis of humic substances from biomass, wherein the process comprises the following process steps. Initially a Maillard reaction is performed by heating the first biomass in particular for 1 to 30 minutes, especially for 10 to 15 minutes, and in particular to 150-250°C, especially to 160-220°C, particularly preferably to 170-190°C. The obtained soluble impurities are extracted from the obtained second biomass using water. The remaining first solid is subjected to torrefaction under a protective gas atmosphere at 180-300°C, in particular at 190-250°C, in particular for 0.2 to 4 hours, especially for 1.5 to 2.5 hours. An obtained torrefied second solid is heated with an excess of a solution of a strong inorganic acid to 120-180°C, in particular to 110-170°C, especially to 130-165°C, in particular for 0.5 to 3 hours, especially for 1.5 to 2.5 hours. The obtained first reaction mixture is filtered and washed with water.

Description

Process for the production of humic substances from biomass such as wood, bark, cereal straw, leaves, herbaceous plants, tree fungi, sewage sludge and other organic wastes

The invention relates to a method for the chemical synthesis of humic substances from biomass according to the preamble of independent claim 1. The invention further relates to an alternative method for the chemical synthesis of humic substances from biomass according to the preamble of independent claim 13. The invention further relates to a method for chemical Synthesis of chitosan from biomass according to the generic term of

independent claim 16.

Humic substances (HS) are natural, biogenic, heterogeneous, high molecular weight organic substances with a yellow to black color, the

Conversion or degradation rate in the ecosystem is relatively low. Due to these recalcitrant properties, humic substances have a high residence or environmental life. Humic substances are polyfunctional and ubiquitously distributed in soils, sediments and waters and make up the major part of the total organic reservoir of these compartments.

Humic substances are an important reservoir of organic carbon in aquatic and terrestrial environmental compartments; In surface waters about 50% of the dissolved organic carbon (DOC) is attributed to humic substances and, despite their polydisperse character, has typical physical and chemical properties which they identify as a group of substances. However, they do not fall into any discrete class of connections like Proteins, polysaccharides or polynucleotides, but are operationally defined and named after the term humus. The depot function, which is essential for life, leads to a fundamental interest in the structure and functionality of this substance class as well as in its importance for ecosystems.

The interest in the composition and structure of these chemically heterogeneous, polydisperse and polyelectrolytic substances with molecular weights of a few hundred to several hundred thousand daltons [Da] is particularly due to their property, due to the high number of donor sites

(mainly carbonyl, hydroxyl, carboxyl and phenyl groups) with many natural and anthropogenic chemicals compounds, such as in complexation reactions with metal ions. Humic substances therefore play in

Rivers and river systems as well as in soil an important role in the transport, but also the toxicity and bioavailability of metal ions, the mobility is dependent on their molecular weights. The interactions and equilibria that occur in nature that occur between

Metal ions in the dissolved phase and the colloidal phase of the humic substances are complex because they are steady state equilibria.

The characterization of humic substances in terms of their composition and structure is difficult because it is a polydisperse class of substances and since conformations and complexing properties depend on parameters such as pH, Eh and ionic strength.

Humic substances are produced via the path of decomposition of dead organisms and a subsequent humification process. In doing so, HSs become different via different chemical and biochemical pathways formed natural conditions, which is why no binding gene pathways and reaction mechanisms can be stated.

Soils are the primary source of education and activity for humic substances. However, humic substances have already been detected in leaves and parts of plants without soil contact which are in the process of aging (senescence). Partial microbial decomposition of dead plant parts and animal remains and excrements of terrestrial and ground animals, under the influence of enzymes from high-polymer compounds, produces aliphatic and aromatic individual building blocks which are the starting materials for humic substances. The conversion of the organic substance into humic substances is called humification. From the

aromatic fragments are formed via free-radical intermediates in the so-called radical phase, the humic acid precursors (HsV), in the implementation of other, present in the soil inorganic and organic compounds are incorporated into the Huminstoffsystem. This creates a system of uneven but stabilized natural products.

Each particle can react with each other, which is why, as a result of random events, neither a linear course of reaction nor a defined chemical constitution of the end products can be expected.

The composition, structures and properties of humic substances vary widely due to the variety of pathways and are dependent upon the conditions of the environment in which they are formed. Table 1 describes typical properties.

Humic substances consist of different building blocks, especially lignin,

Polysaccharides, proteins, OH-containing aromatic (poly) carboxylic acids, quinones, sugar fragments, oxygen- and nitrogen-containing heterocycles and various amino acids. The molecular units are by different bridges (-0-, = NH, = CH2, -N = = C = 0, -S-, even longer

Hydrocarbon chains) in different proportions linked together. Humic substances are typical despite their polydisperse character chemical and physical properties that they use as a group of substances

distinguished.

The properties of humic substances are closely related to the type and amount of functional groups contained. Some functional groups are with their main origin and effect on the properties of

Humic substances listed in Table 2.

Due to their heterogeneous composition, humic substances can not be subdivided according to structural aspects. Instead, the substance class is based on an alkaline extraction into the fractions

Fulvic acid, humic acid and humins are classified. The humic substance fractions and their operational definitions are listed in Table 3. Fulvic acid, humic acid and humins are detectable after extraction from fossil parent substances such as Leonhardite or brown coal and can also be characterized with standards. In soil, some research groups believe that these substances are part of a soil continuum model (SCM) and not as such in a defined form. However, since the present invention produces humic acid and fulvic acid, and since these can be uniquely characterized with standards, these terms are used below. The fulvic acids differ from the humic acids of a sample essentially by their lower molecular weight, by the higher average oxygen, lower carbon and nitrogen content and by the usually higher content of functional groups. The proportion of polysaccharide building blocks can be up to 30% for fulvic acids, aromatic

Components are hardly available. Fulvic acids, as well as their salts, the fulvates, water-soluble and fortuitous metal ionic compounds, with metals which may have multiple oxidation states, are particularly preferably transition metals with several oxidation states such as iron (Fe (II) / Fe (III)), manganese (Mn (II) / Mn (IV), cobalt (Co (II) / Co (III)), chromium

(Cr (III) / Cr (VI) and vanadium (V (III) / V (V)), in particular manganese (IV) - and

Dissolve iron (III) oxides with reduction and bind metal ion complex. The humic acids have a higher molecular weight, contain more aromatic moieties and methylene groups, but fewer polysaccharide fragments than the fulvic acids. Humic acids are sparingly soluble in water and also form with polyvalent cations (calcium, magnesium, iron and

Aluminum) poorly soluble compounds, the so-called humates. The higher solubility in caustic soda or potassium hydroxide is due to the effect of

Sodium cations / potassium cations on the fact that dissociation of weakly acidic groups increases the pH-dependent charge of humic acids and thus facilitates the hydration. Furthermore, the pH increase increases existing bonds to other humates. The acid character of the humic acids and thus the ability to exchange cations based as in the case of the fulvic acids mainly on the presence of carboxyl and phenolic OH groups.

The large number of possible starting materials, the complex genesis and the lack of reaction-controlling mechanisms are the reason that humic substances do not have a uniform structural formula. It is believed that at least for high molecular weight humic substances in a sample, there are no two identical molecules. Even if it were possible to elucidate the structure of a humic substance particle, the result would not be of much use, since the other molecules present in a sample have different structures. The properties of humic substances observed from the outside are thus to be understood as the sum of many different individual properties; This is also evident in the characterization of humic substances. With different methods, wide mixed signals are obtained.

By fractionation of humic substances can generally the degree of Polydispersity can be reduced. The fact that humic substances consist of a complex and heterogeneous mixture of compounds is shown by the failed attempts to separate these materials into fractions of discrete compounds. With the most diverse separation methods, only fractionations could be achieved which were able to determine and reduce the degree of heterogeneity of the samples, but none could even approximately isolate a material that was pure humic matter ('pure' in the classical sense as 'pure chemical' or 'pure group of chemicals'). In this regard, humic substances represent a unique category of natural products, which is characterized by their heterogeneity.

Nevertheless, it is useful to describe and understand the characteristics of humic substances to know structural models when looking at theirs

Weaknesses, especially the fact that they are not the reality, is aware.

The most important for the soil and aquatic systems

Mineral retention function and plant-systemic, catalytic function of humic substances and the function of improving the soil structures and retention capacity of water and nutrients, but also the partial binding and neutralization of pollutants has led to increased humic matter by extraction from peat, Leonhardite, lignite but also synthesis humin-like substances from sugars and amino acids have been driven by low-temperature Maillard reactions.

The disadvantages of extractions and precipitations from leonhardite, lignite and also peat are the heavy metal concentrations of mercury, lead, cadmium and other metal ions which lead to very costly and complicated separation processes, as well as the low functionality of Maillard's. Reactions of synthetically produced karikines or butenolides.

Another serious drawback is the low extraction efficiency of leonhardite and lignite with high levels of unreacted

Raw material, which also harmful by the extraction method

Produced residue or waste streams, which are neutralized separately and in

Special waste landfills must be stored.

Frequently, fresh organic substances from the ongoing material cycles are used to improve the soil.

In order to improve the soil quality, it is easy to obtain manure, e.g. Stable manure, to be used. Farmyard manure acts to improve the soil and nutrients to the soil. It has been shown that stable manure has a positive influence on the water retention capacity of light sandy soils and the soil air balance. However, the duration of action of manure is relatively low. Humic acids are only present in cow dung up to 10%. Similarly, residues from the digestion of manure, green waste or organic waste can be used for soil improvement.

Also known is the use of compost, a decomposition product of vegetable and animal waste. Accordingly, the nutrient contents of the various compost species differ greatly. Compost has a high air capacity. Its water retention capacity is low. Biodegradation by soil-borne bacteria takes place within a few weeks. Based on the starting material, only 3 to 10% of the incorporated carbon is recovered as humic substances in the end product, the majority of the carbon is released into the air via CO 2 formation or is removed during composting by leaching into the sewage treatment plant.

As organic soil improvers, various bark products such as bark mulch, bark humus and bark substrates continue to be used proposed and used. Bark mulch is raw, unfermented (not composted) bark. Bark humus is composted bark.

Growth inhibiting substances are used here during the

Rebuilt composting process to short-chain humus substances.

Bark humus has both soil-improving and fertilizing effects.

Bark substrates are processed clay, peat or other aggregates prepared finished culture substrates or potting soil with 30% to 60% share of

Bark humus. From FR-PS 2 123 042, FR-PS 2 224 421, DE-PS 2 651 171 and DE 3 040 040 methods for composting and humification of shredded bark have become known, which will additionally add inorganic nutrients or peat composting process to to improve the product properties. However, all these products have a lower one

Water retention capability, i. more frequent glazing is required. Nutrient adsorption is also limited. The effect as a permanent humus is limited; The degradation by soil bacteria is also like in compost within a few weeks.

To improve soils, wood waste substrates are also used. These specially treated wood waste products, like bark humus, have a low water retention capacity. Wood fibers that are not fertilized, in addition to bark humus additionally lower

Nutrient contents. Untreated wood waste, such as sawdust or wood chippings, will trap nitrogen in the soil, i. when applying such substances, sufficient nitrogen must be added in addition. When using sawdust, it must be mixed very intensively with the soil, as sawdust nests prevent the penetration of water into the soil. The use of pure

Wood products for soil improvement is thus rather disadvantageous. Therefore, wood pulp is often fertilized or as culture substrates in addition

Mixture with peat or clay used. In DE 101 23 903 it is proposed xylitol, the designation for the remaining wood components in lignite, in digested form, during the digestion process in mills or extruders with nutrients, substances for adjusting pH or clay materials mixed to the mixture as To use soil conditioner. The proposed digestion process is very time-consuming and limits the available humus constituents, which are used as a food source for microorganisms and for the desired

Plant growth are available. Also known is the sole use of peat products, which are characterized by its good water holding ability at the same time high air content. As a result, peat is considered

Raw material for the production of humic acid soil improvers used in large quantities. Since it contains hardly any nutrients and has a low pH, targeted fertilization and limescale is necessary for different plant species. While the peat supply is associated with the destruction of valuable wetlands for rare animals and plants, lignite is cheap and in large quantities without appreciable additional environmental impact than

Humic acid source available. The humic acid selection from this and their use as soil improvers instead of peat can help to ensure that the habitats of the marshes are not irretrievably lost. In DE 101 20 433 a process for the production of Dauerhumusstoffen from soft lignite is described. Thereafter, soft lignite should be mixed with clays or clays and subjected to wet pulping or other intimate mixing. This substance is to be introduced into soils. Since the product produced does not contain any short- and medium-term available humus constituents despite the high cost, the resulting products are not very suitable to contribute to soil improvement.

Another source of humic acids are coconut-processing materials, in particular the short and dusty wastes of fiber processing otherwise difficult to use. The classical method for the extraction of humic acids is the extraction of peat or lignite with dilute aqueous sodium or potassium hydroxide solution. The humates dissolve in the extraction solution and are filtered off,

Decanting or centrifuging the undissolved peat or

Coal ingredients isolated. After acidification of the extract with excess mineral acid, water-insoluble humic acids are formed, which can be separated. For use as a soil conditioner, predominantly lignites are extracted with aqueous ammonia, as set forth in US Patent 3,770,441. The resulting extract is then neutralized with phosphoric acid and enriched with micronutrients. In the US Patents 31 1 1404, 3264084 and 3544295 consuming and expensive methods for the production of dry ammonium fertilizer fertilizer by treatment of lignite with phosphoric acid and then with ammonia as

Extractant described. All of these methods have some disadvantages. Thus, only a small proportion of the humic acids is extracted with the weakly basic NH3 and the oversized humic acid fraction is lost with the coal residue after its separation. In addition, a considerable technical effort is required to separate the alkaline humate-carbon suspension, since the fine coal particles are difficult to settle or easy to

Lead to blockage of filters.

The resulting extraction solutions are highly diluted and usually need to be further used as soil conditioners for further use

Energy consumption to be concentrated.

In US Pat. No. 4,319,041 it is described that humic acid-containing coal is mixed with water and extracted with aqueous solutions of sodium hydroxide solution, potassium hydroxide solution or ammonia with stirring so that the pH remains in the range of 6.5-8. The process is finished after 40 hours. It will receive a highly diluted humate solution, which also consuming the coal residue must be separated and then concentrated. In US Patent 3,076,291 lignite is extracted with dilute aqueous NH 3, KOH or NaOH solutions. The separated from the coal residue, then concentrated and neutralized humate solutions are used as a means of improving the germination of the seed. Laid-open publication DE 19859068 A1 describes that lignite is suspended in an aqueous-ammoniacal medium having a pH of greater than 9 and in the process is partially dissolved and oxidized in the aqueous-ammoniacal medium. The organic fertilizer is recovered after thickening or drying as a dispersion. The

Starting brown coal can be added to this process with additions of lignin or cellulosic products from industry and forestry. An addition of macro and micronutrients is possible.

The process avoids the elaborate separation of humate solution and coal residue, but requires additional energy to thicken or dry the product and opens due to the low basicity of NH3 against alkali only a small proportion of the coal contained

Humic acids. In order to increase the soluble amount of humic acid available to the plants, an additional oxidation step is instead incorporated, which means an increased technical complexity and only slightly increases the amount of available humic acids.

In patent WO2007125492A2, the oxidation of pure substances of the group of the saccharides, sucrose, glucose and fructose is carried out with the aid of increased pressure and temperature while blowing in air or oxygen. However, this is done with relatively expensive raw materials, and these raw materials must be refined to a heavy metals-free level, making the resulting humic substances relatively expensive. Since in this application, in addition, the molecular size is limited by dialysis to 600 to 1000 daltons, this is the type of

Production very inefficient and therefore not suitable for agricultural purposes. The resulting / produced low molecular weight compounds are used only for pharmaceutical purposes such as the disinfection of Oral mucosa and decomposition of biofilms in the oral cavity.

Of course, with the present invention, the complex sugars of hemicellulose, cellulose, lignin and chitin can also be oxidized by blowing in atmospheric oxygen or pure oxygen in a pressurized vessel with pressure increase and temperature increase after biomass firing, but then the oxidation is slower but more controlled expires. The resulting, as in the pressureless acid oxidation, resulting

Humic substances are used entirely as fulvic acid or humic acid, and therefore this process is much more efficient than W02007125492A2. By virtue of the titration, the rate of reaction of the subsequent oxidation is slowed down so much that a run-away of the oxidation reaction is prevented, which can easily be the case when using pure, refined sugars.

In US Patent 5876479 a soil conditioner based on

Humic acids are described, for the production of which an aqueous solution of humates is added successively with sodium bicarbonate to lower the pH, a protein source such as animal meal or blood, citric acid, yucca extract, lime and Tang. This suspension is then fermented for 10 days. The solution obtained after separation of insoluble components is used as a soil conditioner.

Furthermore, it is known from US Patent 2317991 that a fermented

Mixture of protein materials and humates can be used as a plant growth stimulator.

These processes have the disadvantages of producing highly diluted solutions which require high expenditures for transportation to the field, Humate expensive to buy and the soil conditioner in one

time-consuming and odor-disturbing production process is produced.

Finally, DE 101 23 283 describes a process by which fine-grained lignites are digested in alkaline solution and, after addition of inorganic supplementation and / or neutralization substances without further treatment steps, a stable humate-humic acid-continuous humus nutrient suspension is produced. This product has been proven in practice, but the effect is limited in extremely nutrient-poor soils.

DE 20 2009 007 252 U1 describes the structure of humic acid-containing organic compounds (humic complexes) based on bitumen emulsions for small-scale use.

The published patent application DE 43 25 692 A 1 describes the structure of a hydrophobic layer in the soil to contain the evaporation, ie the evaporation of water from the soil. The approach used in the present patent is to curb transpiration, that is, consumption over the plant itself.

A similar approach to contain the evaporation describes the process in the published patent application DE 33 18 171 A 1. Here, however, instead of a hydrophobic layer, a film is incorporated in the soil, the

Restrict evaporation of water or even prevent it.

As early as 1971, Mitscherl et al., In the published patent application DE 22 65 298, describe the structure of a water-storing layer in the subsoil that makes water available to plants. Basis for such a layer are gas concrete and expanded clay aggregates of a certain size. However, such a method is extensively applicable over a large area. The patent EP 13 58 299 B1 also describes a process for the production of soils or

Separating layers to contain the evaporation. To increase the water storage capacity, a number of inorganic and organic substances are used. The use of artificial inorganic and organic soil improvers in the form of polymers and hydrogels capable of reversibly storing water is also increasing. In most cases, these substances are only partially usable for use in desert soils, as these substances are not heat tolerant, only limited UV resistance and are no longer functional at high salt levels in the soil. In addition, artificial soil conditioners still have a number of unanswered questions regarding the metabolites that may be produced by natural degradation or chemical conversion in the soil. The use of rock flours and clay minerals is intensified, but their effect is limited; In some cases, they still have antagonistic effects in the soil with regard to the availability of potassium and magnesium

especially in the two-layered and three-layered clay minerals potassium and magnesium are stored, which is no longer plant available under dry soil condition.

Humic acid may have a cation exchange capacity of between 200 to 700 meq / 100 grams depending on the distribution of the various components, while fulvic acids may reach between 500 to 1400 meq / 100 grams. Humic substances are also very interesting due to their

electrochemical redox properties, which are promising for the production of redox flow batteries.

The object of the invention is therefore to produce humic substances in closed processes from biomass and agricultural and wood-based waste, while avoiding waste with (almost) 100 percent

Reaction of the raw materials in the desired target products, wherein the known from the prior art disadvantages should be avoided. The object is achieved by a method for the chemical synthesis of

Biomass humic substances having the features of independent claim 1, by an alternative method for the chemical synthesis of humic substances from biomass having the features of independent claim 13 and by a method for the chemical synthesis of chitosan from biomass having the features of independent claim 16.

As biomass, in particular as the first biomass applies in the following

General: agricultural and forestry waste, wood, bark, grain straw, leaves, krautigen plants, tree fungi, sewage sludge and other organic waste, as well as many other types of plant biomass. In the following, a solution of KOH and / or NaOH in water, in particular a 0.1 to 2.0 molar solution of KOH and / or NaOH in water, in particular a 1.0 molar solution of KOH and / or NaOH in water, will generally be considered as alkaline earth hydroxide solution , As a solution of strong inorganic acids, the following generally applies a solution of sulfuric acid and / or

Phosphoric acid and / or nitric acid, in particular a 0 to 40% solution of sulfuric acid and / or phosphoric acid and / or nitric acid,

preferably a 15 to 35% solution of sulfuric acid and / or

Phosphoric acid and / or nitric acid, more preferably a 15 to 25% solution of sulfuric acid and / or phosphoric acid and / or nitric acid. In the following, a mother liquor is generally the liquid extract which is obtained after filtration and / or washing of a reaction mixture and / or solid. Hereinafter, heating generally refers to heating and holding at a certain temperature range. In particular, titration may also be heating. In a pressure vessel, in the following, generally in a container which is suitable for carrying out a reaction under pressure and / or for carrying out a reaction under pressure. Under pressure, this means a pressure greater than that

Atmospheric pressure. Oxygen in the following is generally pure oxygen or a gas mixture with oxygen. According to the invention, a process for the chemical synthesis of

Humic substances from biomass, in particular from a first biomass proposed, wherein the method comprises the following method steps. It is carried out with the first biomass of a Maillard reaction by heating the first biomass, in particular for 1 to 30 minutes, in particular for 10 to 15 minutes and in particular to 150-250 ° C, in particular to 160-220 ° C. , more preferably 170-190 ° C, is heated.

A Maillard reaction is a non-enzymatic browning reaction, which can also be observed, for example, when frying and frying foods. In this case, amine compounds (such as amino acids, peptides and proteins) are converted to new compounds with reducing compounds under the action of heat. A Maillard reaction according to the invention is preferably carried out in a temperature range between 160 and 200 degrees Celsius, and the residence time in this temperature range is generally between 0 and 60 minutes, and preferably between 15 and 30 minutes. In addition, depending on the nature of the first biomass after a residence time of about 1 to 60 minutes, preferably 15 to 40 minutes, more preferably 25 to 30 minutes, at a temperature level of 100 to 220 degrees Celsius, preferably 160 to 200 degrees Celsius, more preferably 175 to 185 degrees Celsius the Maillard reaction take place.

The generated Maillard reaction of the first biomass is thus between sugars, starches and amino acids, peptides, proteins under heating.

For this purpose, the first biomass may in particular be finely ground in order to favor the Maillard reaction by increasing the surface area.

From the obtained second biomass, ie the solid which is obtained from the Maillard reaction of the first biomass, soluble impurities are extracted by means of water.

In particular, the water-soluble reaction products can also be extracted with hot water after the Maillard reaction from the resulting second biomass and then thickened. The remaining from the extraction of the second biomass first solid is torrifiziert under a protective gas atmosphere at 180-300 ° C, especially at 190-250 ° C, especially for 0.2 to 4 hours, torrifiziert especially for 1.5 to 2.5 hours. The first solid should therefore last several hours until

Achieve the desired degree of drying / decomposition torrifiziert. Torrification is the thermal treatment of biomass without access of air, which can lead to pyrolytic decomposition and / or drying. In the present biomasses of all processes according to the invention, aromatic structures are produced in the biomass by the torrification, which later react further in the oxidation step.

The resulting torrified second solid is heated with a solution of a strong inorganic acid in excess, preferably heated to 120-180 ° C, in particular 110-170 ° C, in particular 130-165 ° C, in particular for 0.5 to 3 hours, specially heated for 1.5 to 2.5 hours

(Säurekochung). In this case, an oxidation takes place with formation of fulvic acid. Alternatively, the oxidation can also be done by the torrifiziert second

Solid is oxidized with another oxidizing agent, such as by the torrifizierte second solid is suspended with water and oxidized with the supply of oxygen, in particular in a pressure vessel, as described in more detail in the alternative method of the invention. Oxidizing agents such as hydrogen peroxide, in particular hydrogen peroxide in a low concentration, are also suitable for the oxidation of the biomass.

At the same time, the resulting wood acetic acid fractions can be condensed separately during the first solidification of the first solid.

In the case of the first solid, the resulting Maillard products and carbohydrates as well as hydrolactones and

Strigolactone be mitgebildet.

The first reaction mixture obtained after boiling the torrified second solid with a solution of a strong inorganic acid is filtered and washed with water. The fulvic acid formed by oxidation can therefore be dissolved by washing the remaining solid until the wash water is pH-neutral. The oxidation step converts the aromatic structures generated during the titration into aliphatic compounds,

or to aliphatic compounds having an aromatic "backbone", that is to say aromatic part structures The advantages of the process according to the invention include:

- (almost) complete implementation without waste

High yields

- efficient and cost-effective

Easily automatable As further additional process steps for a process according to the invention, the following steps can optionally be carried out.

The third solid obtained from the first reaction mixture can be boiled at 120 to 160 ° C, especially at 130-150 ° C with alkaline earth hydroxide solution and dissolved. In this case, for example, refluxing with 1 molar KOH.

The obtained after boiling the third solid with alkaline earth metal hydroxide solution second reaction mixture can be neutralized by means of sulfuric acid and / or nitric acid and precipitating solids can be separated. By further lowering the pH to a range of pH 0 to pH 2.5, in particular of pH 2, humic acid can be precipitated from the first mother liquor obtained after neutralization of the second reaction mixture. From a obtained after precipitation of the first mother liquor second

Mother liquor can be precipitated and / or separated at pH 0 to pH 1, in particular at pH 0, calcium sulfate and / or magnesium sulfate and / or potassium sulfate, and / or the resulting second mother liquor can be concentrated and neutralized.

In order to obtain a high yield of karrikines in the Maillard reaction, the ratio of sugars to amino acids in the first biomass should be between 1: 1 to 1: 3, and preferably 1: 2.

Is in a novel process in the first biomass too little sugar or amino acid (in relation to the amino acids or

respectively sugar), the Maillard reaction can not be complete. By infiltrating sugar or amino acid into the first biomass, the level of sugar or amino acids can be increased. The proportion of the missing substance is therefore increased in the raw material.

In a special embodiment, in which a high proportion of

Carotenoids present in the raw material (in the first biomass) are formed during the process according to the invention as a further reaction product Strigolactone and Hydrolactone, in particular high levels of Strigolactonen and Hydrolactonen formed.

The first solidification may be carried out in a temperature range of 180 to 300 degrees Celsius, preferably 190 to 250 degrees Celsius, more preferably 235 to 250 degrees Celsius. In this case, the first solid can also be pyrolyzed. The temperature of the titration may be maintained at a constant temperature for between 1 and 4 hours, preferably for 2 to 3 hours. In this case, the titration can be carried out under an inert protective gas such as carbon dioxide, argon, nitrogen or other known protective gases or under vacuum. In a method according to the invention, the respective proportions of humic or fulvic acids in the end product can be controlled via the process temperature. At higher pyrolysis / titration temperatures, higher levels of fulvic acids are present as the formation of fulvic acids increases

Temperatures is favored. At low pyrolysis / titration temperature, higher levels of humic acid are produced, as formation of

Humic acid is favored at lower temperatures.

The obtained torrified second solid may be cooled under inert gas and / or refluxed with acid, the

Acid boiling temperature between 1 10 to 180 degrees Celsius, preferably below 130 to 165 degrees Celsius.

The acids used in acid cooking may be one or more acids, preferably one of the acids or a mixture of one or more of the acids sulfuric acid, nitric acid, phosphoric acid or concentrated acetic acid or citric acid. The acid concentrations in the acid cooking can be from 1% by mass to 40% by mass, preferably 15% by mass to 35% by mass, and more preferably 25% by mass

Mass percent to 30 percent by mass of the solid used. The material obtained from the acidification (first reaction mixture) can be filtered first and then the filter cake obtained can be washed with distilled water to pH neutral, the wash water is added to the filtrate of the first reaction mixture and then the filtrate plus wash water is concentrated.

After the acidification step, mineral salts precipitating upon concentration can be separated by further filtration and as

Fertilizer fraction can be removed from the process, this can predominantly Nitrates, phosphates, acetates, citrates and sulfates, depending on the type of acids used. Of course, these mineral salts can continue to precipitate in later steps of the concentration and then filtered off.

The remaining after filtering the first reaction mixture third solid can be added to the cooking with alkaline earth metal hydroxide solution with 0.1 normal to 2 normal KOH, preferably with 0.5 normal to 1 normal KOH and under reflux at a temperature range of 130 to 160 degrees Celsius over 1 to Be cooked for 3 hours.

All solids which go into solution during the performance of the process according to the invention (and which are not filtered off or the like) form the humic acid fraction, the solids usually being boiled until all have gone into solution.

The humic acid of the second reaction mixture can be neutralized by adjusting it to a pH of 8 to 9, preferably a pH of 8.5, and after concentration, the resulting salts (e.g., potassium salts) can be separated by filtration. Among potassium salts are to be understood inter alia salts of potassium and other alkali metals as well as sodium and lithium.

The obtained humic acid can be successively oxidized to fulvic acid by adjusting a pH of about 14. This step can be carried out in particular after the neutralization of the second reaction mixture.

The humic acid and fulvic acid can be enriched after neutralization with mineral ions or concentrated, and then further processed with a spray dryer in a powdered concentrate. Another alternative process according to the invention for the chemical synthesis of humic substances from biomass, in particular from a first biomass, comprises the following process steps

A Maillard reaction is carried out by heating the first biomass, in particular for 1 to 30 minutes, in particular for 10 to 15 minutes and in particular at 150-250 ° C, in particular at 160-220 ° C, particularly preferably 170-190 ° C, heated.

Soluble impurities are extracted by means of water from a second biomass obtained from the Maillard reaction.

The first solid obtained after the extraction of the second biomass is torrifiziert under a protective gas atmosphere at 180-300 ° C, especially at 190-250 ° C, especially for 0.2 to 4 hours, torrifiziert especially for 1.5 to 2.5 hours.

The torrified second solid is oxidized with an oxidizing agent, in particular suspended with water and oxidized with the introduction of oxygen. This step can be carried out in particular in a pressure vessel.

The third reaction mixture obtained after the oxidation is filtered and washed with water.

Potential oxidizing agents include oxygen, ozone,

Peroxides such as hydrogen peroxide, hypochlorites, perchlorates, percarbonates and iodine are used

Thus, it can be seen that the first alternative method of

previously described method differs only by the oxidation step. All further additional process steps described for the process according to the invention can thus also be carried out for this process.

The oxidation step may be performed by blowing air or oxygen into the 150 to 170 degree hot water-titrated material mixture using a stirred pressure vessel. From the fourth mother liquor obtained after the filtration of the third reaction mixture, calcium sulfate and / or magnesium sulfate and / or potassium sulfate can be precipitated and / or separated at pH 0 to pH 1, in particular at pH 0, and / or the resulting fourth mother liquor can be concentrated and neutralized.

According to the invention, a process for the chemical synthesis of chitosan from biomass, in particular from a third biomass, is furthermore disclosed

proposed, the method comprising the following method steps. A Maillard reaction is carried out by adding the third biomass for 1 to 30 minutes; in particular for 10 to 15 minutes and at 150-200 ° C, in particular at 160-180 ° C, is heated. Soluble impurities are extracted by means of water from a fourth biomass obtained by the Maillard reaction of the third biomass. A obtained after the extraction of the fourth biomass fifth solid is cooked at 140 to 180 ° C, especially at 150-170 ° C with alkaline earth hydroxide solution.

A solid obtained after boiling the fifth solid with alkaline earth metal hydroxide solution can be further processed as a second solid whose processing has already been described in the above-described inventive method for the chemical synthesis of humic acid from biomass and the additional additional process steps, which are also described above. In a method according to the invention, in particular the following steps can be carried out, which can be carried out successively. However, of course, further intermediate steps can be carried out, or, depending on the type of biomass, the chronology of the steps can be adapted. The following explanations are a very precise description of a possible procedure, which has already been described more broadly, with further optional and variable ones

Process procedures. The following method steps also contain more detailed statements on the usefulness of the above already described Process steps, which are thus also to be transferred to the procedural guides described above.

(Step 1) Since many of the biomass types mentioned at the beginning have high sugars and protein contents, the sugar or starch present in the case of woody or straw-like biomass with appreciable contents of hemicellulose with the addition of amino acids is first of all given a humin-like substance group via a Maillard reaction. namely produced butenolides or Karrikine by heating to 160 to 220 degrees Celsius, preferably 170 to 190 degrees Celsius. After several minutes, between 0 to 30 minutes

preferably 10 to 15 minutes, the Maillard reaction is completed so far that the resulting products can be separated via hot water extract from the remaining solid. The products of the Maillard reaction

determine the proportion of nitrogen and the proportion of plant dormancy-breaking karrikines in the final product. (Step 2) The remaining solids after separation of the water-soluble products of the Maillard reaction are now torrifiziert in a temperature range between 200 to 280 degrees Celsius, with residence times at T = Constant of 0.2 to 4 hours, preferably 1.5 to 2.5 hours are sought. The titration takes place under protective gas (CO 2, argon, nitrogen, etc.), with nitrogen being the preferred protective gas. The resulting

Wood acetic acid fraction is condensed out via a condenser and fed into fertilizer or pesticide production.

In the case of use of chitin-containing tree fungi or other chitin-containing fungi or fungal mycelia or other chitin-containing raw materials after heating to 160 to 180 degrees Celsius and water extraction of the resulting Karrikine the residue with the help of KOH at 150 to 170 degrees Celsius boiled under reflux and won the resulting chitosan. When using biomass with a high content of carotenoids, in addition to the already mentioned substances such as fulvic acid, humic acid, carmine, etc., also hydrolactones and strigolactones are produced.

Temperature and residence time control the compositional ratio of fulvic and humic acids in the final product. At low temperature and shorter residence time, a higher proportion of humic acids, and higher

Temperature and extended residence time a higher proportion of fulvic acids. In addition, the residence time is also used to control the ratio of the carboxyl-carbonyl hydroxyl groups (step 3). The torrified solid is then mixed with a mixture of several acids, preferably sulfuric acid, phosphoric acid and nitric acid, at a concentration of 0 to 40%, preferably 15 to 35 %, more preferably 25-30%, boiled under reflux and oxidized. Cooking times at temperatures of between 1 10 to 170 degrees Celsius, preferably 130 to 150 degrees Celsius are between 0.5 to 3 hours, preferably 1.5 to 2.5 hours. The acid addition is about 20% more than that

Acid consumption, so that after oxidation with the residual acid, further required mineral substances are released from the residual acid and the resulting

Fulvic acid can be attached as a mineral fulvate. This allows tailor-made fulvic acid partitions to be precisely defined

Generate mineral composition.

Alternatively, a mixture of water and torrified material can also be oxidized in a pressure vessel with the injection of air or pure oxygen, wherein there is no as much pH drop as when using acids for oxidation.

The resulting fulvic acid is in high depending on the concentration at pH 0

Dilution pale yellow and deep red in high concentration, and upon neutralization with KOH to pH 6.5 to 7 dark brown to black. This resulting fulvic acid is water-soluble in any pH range from 0 to 14 without filter residue. When fulvic acid is concentrated at pH 0, the precipitating gypsum (calcium sulfate, possibly also magnesium sulfate) can be fractionally separated by filtration if necessary and a separate tailor-made fertilizer mixture can be produced. After concentration, the residual acid is neutralized with KOH and the precipitating salt either left or separated by filtration or centrifugation and used as a separate fertilizer fraction. Subsequently, the concentration of the liquid with fulvic acid can be adjusted by further concentration to the desired value, or be converted by spray drying in a powdery solid. The rest-kalimengen in the

Depending on the course of the process, fulvic acid amounts to between 1 and 15%, preferably less than 10%.

(Step 4) The solid remaining after the oxidation and separation of the fulvic acid is washed with distilled water until the water is pH neutral. Subsequently, this washing water fraction, which is still a relatively high

Contains fraction of fulvic acid and residual acids, concentrated and neutralized and added to the main fraction of fulvic acid.

The remaining solid consists of pure humic acid with adhering minerals from the acid treatment such as phosphorus, sulfur and

Minerals from the raw material that have not entered the fulvic acid fraction. There are also small amounts of nitrogen as NO2 or NO3 deposits detectable. If a liquid humic acid fraction is desired, then this solid is refluxed in 1 molar KOH until completely dissolved. Cooking times of 0.2 to 4 hours, preferably 1.5 to 3 hours, in particular 2 to 2.5 hours at temperatures between 120 to 150 degrees Celsius, preferably 140 to 150 degrees Celsius are applied. These too Liquid can then be adjusted by concentration to the desired potassium content.

Upon neutralization with either H 2 SO 4 or HNO 3, potassium sulfate or potassium nitrate may be crystallized out, separated by filtration, and

crystallized material of the separate fertilizer fraction are added in the appropriate mixing ratio or find use as a sole agent.

The liquid humic acid precipitates when lowering the pH to pH 2 in its entirety as a crystalline humate. Usually, the liquid humic acid but only with the addition of acids, preferably one of the major acids sulfuric acid, phosphoric acid or nitric acid, more preferably sulfuric acid, with the formation of crystallizing potassium sulfate to the desired pH range of 8 to 9, preferably 8.5 lowered. The resulting potassium sulfate or potassium nitrate or potassium phosphate is removed by filtration or centrifugation and fed to the fertilizer production.

Throughout the process will be no waste or polluting

Process waters generated. The C02 also produced by the formation of carbonate is formed by carbonate formation as calcium carbonate, potassium carbonate or

Magnesium carbonate fixed. The raw material used or the carbon fraction are converted to 70% to 100% in humic substances and fertilizer. A tailor-made composition of humic substances and fertilizers is possible in every variation.

The resulting humic and fulvic acids are characterized by high

Cation exchange capacities (CAC), which are generally well over 200 meq / 100 g. CAC is an important parameter of soil fertility.

The process control and the chemicals allow a reduction in costs compared to humic substances from peat, Leonhardite, lignite or Synthes by an order of magnitude. Most used biomasses generate additionally a contribution to expenses in the form of disposal fees and thereby additionally reduce the overall process costs.

In the following the invention and the prior art will be explained in more detail by means of embodiments with reference to the drawings.

1 shows an exemplary FTIR analysis using a sigma

Humic acid standards

Figure 1 shows an exemplary FTIR analysis using a sigma humic acid standard 53680-10g lot no. NrBCBN171 1V; CAS NR1415-93-6 in comparison with a FTIR analysis of the product of a

process according to the invention. The FTIR analyzes of the various

Humic acid samples yield almost congruent transmission curves in almost all wavelengths. Consequently, from a process according to the invention, valuable humic acid combinations which largely match the humic acid combinations from the soil result.

Annex I: Tables

Table 1: Typical properties of humic substances

Table 2: Functional groups of humic substances: origin and effect

Table 3: Operational Definitions of Humic Acid Fractions

Table 4: Summary of the general properties of the humic substance fractions in the form of general tendencies -32-

Claims

claims

1. Process for the chemical synthesis of humic substances from biomass, in particular from a first biomass

characterized in that

Method comprising the following method steps:

a) Performing a Maillard reaction by heating the first biomass, in particular for 1 to 30 minutes, in particular for 10 to 15 minutes and in particular at 150-250 ° C, in particular at 160-220 ° C, more preferably 170-190 ° C, heated b) soluble impurities are extracted by means of water from a second biomass obtained from step a)

c) a first solid remaining from step b) is torrified under an inert gas atmosphere, in particular at 180-300 ° C., preferably torrified at 190-250 ° C., in particular for 0.2 to 4 hours, in particular torrified for 1.5 to 2.5 hours d) a torrified second solid obtained from step c) is heated in excess with a solution of a strong inorganic acid, preferably heated to 120-180 ° C, in particular 110-170 ° C, in particular 130-165 ° C, in particular for 0.5 heated to 3 hours, in particular for 1.5 to 2.5 hours e) a first reaction mixture obtained from step d) is filtered and washed with water.

2. The method of claim 1 wherein

f) from e) obtained third solid at 120 to 160 ° C, in particular at 130-150 ° C with alkaline earth hydroxide solution is boiled and dissolved

g) a second reaction mixture obtained from step f) is neutralized by means of sulfuric acid and / or nitric acid and precipitating solids are separated off and / or a humic acid is precipitated by lowering and adjusting pH 0 to pH 2.5, in particular of pH 2, of the first mother liquor obtained from step g).

Process according to claim 1 or 2, wherein from the second mother liquor obtained in step e) at pH 0 to pH 1, in particular at pH 0

Calcium sulphate and / or magnesium sulphate and / or potassium sulphate is precipitated and / or separated off and / or the second mother liquor obtained in step e) is concentrated and neutralized.

A method according to claims 1 to 3, characterized in that the ratio of sugars to amino acids in the first biomass is between 1: 1 to 1: 3, and preferably 1: 2, so that a high yield of karrikines is obtained as a result of the Maillard reaction ,

5. The method according to claim 1 to 4, characterized in that at

Lack of sugar or amino acids in the first biomass is increased by infiltration of the content of sugar or amino acids.

6. The method according to claim 1 to 5, characterized in that after in step a) Maillard reaction, the reaction products in step b) are extracted with hot water from the biomass and then thickened.

7. The method according to claim 1 to 6, characterized in that the

Torrification under step c) under an inert protective gas such as

Carbon dioxide, argon, nitrogen or other known shielding gases is performed.

8. The method according to claim 1 to 7, characterized in that the torrified solids fraction obtained from step c) in step d) is cooled under inert gas and / or an acid reflux is fed, wherein the acid boiling temperature between 1 10 to 180 degrees Celsius, preferably below 130 to 165 degrees Celsius.

9. The method according to claim 1 to 8, characterized in that the acids used in step d) are an acid or a mixture of several acids, preferred one of the acids

or a mixture of one or more of the acids

Sulfuric acid, nitric acid, phosphoric acid or concentrated acetic acid, respectively. Citric acid is used.

10. The method according to claim 1 to 9, characterized in that the humic acid obtained in step g) is neutralized by adjustment of a pH of 8 to 9, preferably a pH of 8.5 and after concentration, the resulting salts (potash salts) by filtration be separated.

1 1. The method of claim 2 to 10, characterized in that the humic acid obtained in step g) is successively oxidized by adjusting a pH of about 14 to fulvic acid.

12. The method according to claim 10, characterized in that humic acid and fulvic acid enriched with mineral ions used after neutralization or are concentrated to be subsequently processed with a spray dryer in a powdered concentrate.

13. Process for the chemical synthesis of humic substances

Biomass, in particular from a first biomass

characterized in that

Method comprising the following method steps: h) carrying out a Maillard reaction by heating the first biomass, in particular for 1 to 30 minutes, in particular for 10 to 15 minutes and in particular at 150-250 ° C, especially at 160-220 ° C, more preferably 170-190 ° C, heated i) soluble impurities are made by means of water from a

Step h) extracted second biomass extracted

j) a first solid remaining from step i) is torrified under an inert gas atmosphere, in particular at 180-300 ° C., preferably torrified at 190-250 ° C., in particular for 0.2 to 4 hours, in particular torrified for 1.5 to 2.5 hours k) a torrifizierter second solid obtained from step j) is oxidized with an oxidizing agent, in particular suspended with water and oxidized with the supply of oxygen, in particular oxidized in a pressure vessel with the supply of oxygen or under supply of an oxidizing agent in the

Pressure vessel oxidized

I) a third reaction mixture obtained from step k) is filtered and washed with water.

14. The method of claim 13 wherein

m) a fourth solid obtained from I) at 120 to 160 ° C,

especially at 130-150 ° C with alkaline earth hydroxide solution is boiled and dissolved

n) a fourth reaction mixture obtained from step m), neutralized by means of sulfuric acid and / or nitric acid and precipitated solids are separated off and / or a humic acid by lowering and adjusting pH 0 to pH 2.5, in particular of pH 2, from step n) obtained third mother liquor is precipitated.

15. The method of claim 13 or 14 wherein from the obtained in step I) fourth mother liquor at pH 0 to pH 1, in particular at pH 0 calcium sulfate and / or magnesium sulfate and or potassium sulfate is precipitated and / or separated and / or in step I) fourth mother liquor and neutralized.

16. Process for the chemical synthesis of chitosan from biomass, in particular from a third biomass,

characterized in that

Method comprising the following method steps:

o) a Maillard reaction is carried out by the third

Biomass for 1 to 30 minutes; especially for 10 to 15 minutes and at 150-200 ° C, in particular to 160-180 ° C, is heated p) soluble impurities by means of water from a

Step o) extracted fourth biomass extracted

q) a fifth solid obtained from p) at 140 to 180 ° C,

especially at 150-170 ° C with alkaline earth hydroxide solution is cooked.