Method for producing a molded part from a molding compound

Abstract

The invention relates to a method for producing a molded part comprising a method for producing a molding compound and the method for producing a molded part further comprising shaping the molding compound obtained in the method for producing a molding compound into a molded part. The molded parts according to the invention are suitable, for example, as workpieces, shaping components in a piece of furniture or furnishing, composite materials, cladding parts for buildings or building components, fillers, coatings, insulating materials or building materials, in particular acoustic insulation materials, building material panels and thermal insulation materials.

Description

Field of the invention

[0001] The present invention relates to a process for producing a molded part from a molding compound.

[0002] The molded parts according to the invention are suitable, for example, as workpieces, molding components in a piece of furniture or furnishing, composite materials, cladding parts for buildings or building components, fillers, coatings, insulating materials or building materials, in particular acoustic insulation material, building panels and thermal insulation material. State of the art

[0003] Molded parts are used in a wide variety of industrial sectors, including the automotive industry, buses, rail vehicles, and aircraft for trim parts and other interior components. In buildings, molding compounds are used as construction materials, insulation materials, or furniture, for example.

[0004] Depending on the application, the materials must be as lightweight as possible while maintaining their shape. Many of the composites currently used, especially those in the mobile industry, have a complex structure and are extremely complex and expensive to produce. To reduce weight and maintain acoustic properties, up to ten individual layers of a wide variety of materials are sometimes used to create the desired molded parts or the products produced from them.

[0005] In addition to the complex manufacturing process, questions about recycling and the health risks posed by individual materials also play a role. Many of the materials used can only be recycled using complex processes or disposed of after use, posing significant environmental problems. In addition, there are hidden product properties that pose concerns both during and after use, including, for example, fire retardants, flame retardants, solvents, and plasticizers.

[0006] Another significant factor is the long-term and sustainable availability of raw materials for the production of molded parts. Fossil raw materials will only be available in limited quantities in the medium to long term and are increasingly criticized due to their contribution to global warming and limited recyclability. It is foreseeable that products made from increasingly scarce fossil resources will become more expensive as the prices of dwindling raw materials rise. Furthermore, resource scarcity also contributes to the limited functionality of supply chains. For these reasons, efforts are warranted to replace molded parts made from petroleum-based and increasingly scarce raw materials and to manufacture them from ecologically usable, renewable raw materials that are permanently available in nature.

[0007] The processes known to date, such as those described in DE 31 05 596 C2, DE 23 19 759 A, DE 10 2004 012 458 B4, EP 2 193 899 A1 or US 5,076,986, represent initial approaches, but are unsatisfactory for a variety of reasons. Firstly, aggregates that are environmentally questionable are still being used, and secondly, a number of desired product properties are not being met. Although some materials of natural origin are used here, these still have to be processed using energy- and labor-intensive processes. Nor do they close the sustainable, ecological material and product cycle in the sense of a circular economy. Background of the invention

[0008] Typically, soundproofing and thermal insulation materials are made from melamine resin foam or EPS, plastics that must be disposed of in landfills at the end of their life cycle. Eco-friendly alternatives to plastics already exist, for example, from wood fibers.

[0009] However, compared to the cultivation of wood, for example, which requires additional land and water, hop by-products do not require any additional resources because they utilize waste that would otherwise go unused. The Hallertau region is world-famous for its extensive hop fields. With an annual yield of over 41,000 tons of hop cones on around 17,000 hectares, the Hallertau occupies a leading position: it represents the largest contiguous hop-growing region in the world, accounting for about a third of global hop production. Not to be neglected is the fact that hop processing generates around 250,000 tons of biomass, which is currently only used to a limited extent. This hop waste, consisting of stems, leaves, the training wire, and unwanted cones, accounts for about 85% of the total plant mass. Common practice is for this waste to be spread out on separate fields and fermented there.This process can be problematic because the leachate from the plant mass can seep into the groundwater, and the Hallertau region already struggles with elevated nitrate levels in the groundwater. Furthermore, chemical reactions during the fermentation process repeatedly lead to fires, as well as high greenhouse gas emissions. Approximately 20% of the waste generated in the Hallertau region is sold for thermal recycling to the Wolnzach biogas plant, which is already operating at full capacity. Farmers are then required to take back the resulting fermentation residues and spread them back on their fields, a step many hop growers find burdensome.

[0010] Currently, 25-30% of the world's industrial hemp is cultivated in the EU. With the partial legalization of cannabis by the German government on April 1, 2024, an increase in cannabis plantations in Germany is expected.

[0011] A large portion, approximately 20-30%, of the hemp plant, especially the stems and leaves, often has only limited use. They are often considered byproducts and, in some cases, even disposed of or used as animal feed, mulch, or for energy production. The focus is usually on the valuable hemp seeds or hemp fiber, while the remaining parts have so far been used less extensively, despite growing interest in the sustainable, holistic utilization of the entire plant. Object of the invention

[0012] Against this background, it is the object of the present invention to provide a process which is dedicated to the use of lignocellulose-containing plants, in particular the use of plants of the hemp family (Cannabaceae), preferably hops and / or other plants of the hemp family (Cannabaceae) such as hemp, and in this case in particular previously unused hop waste and / or waste of other plants of the hemp family (Cannabaceae), in order to produce high-quality and sustainable materials.

[0013] Above all, the object of the present invention is to produce high-quality and recyclable molded parts from hops, preferably hop vines, and / or by-products of the hop harvest or waste thereof; and / or from other plants of the hemp family (Cannabaceae), preferably hemp, and / or by-products of the harvest of the hemp family (Cannabaceae).

[0014] This problem is solved by means of the independent claim. The dependent claims further develop the core idea of ​​the invention.

[0015] The development and production of inventive molded parts from inventive molding compounds is based on a comprehensive approach that combines ecological sustainability, circularity, and technical performance. Description of the invention

[0016] In a first aspect, the invention provides a method for producing a molded part, comprising I) a process for producing a molding compound, wherein the process for producing the molding compound comprises the following process steps: Step a) Providing lignocellulosic plants and / or lignocellulosic plant fibres; Step b) comminuting the lignocellulosic plants and / or lignocellulosic plant fibres; Optionally, step c) involves the extraction of lignocellulosic plant fibres from the shredded lignocellulosic plants by separating the lignocellulosic plant fibres from the remaining components of the lignocellulosic plants; Step d1) Carrying out a partial delignification and hemicellulose hydrolysis, wherein the partial delignification and hemicellulose hydrolysis in step d1) comprises the following steps: - cooking the comminuted lignocellulosic plants and / or the comminuted lignocellulosic plant fibers in an agent selected from a group comprising sodium hydroxide, hydrogen peroxide, calcium hydroxide, either individually or any combination thereof; - treating the comminuted and cooked lignocellulosic plants and / or the comminuted and cooked lignocellulosic plant fibers with an agent selected from a group comprising carboxylic acid, mineral acid, either individually or a combination thereof; and further the process for producing a molded part comprises the following process step II): e) shaping the molding compound obtained in d1) into a molded part.

[0017] An alternative method according to the invention for producing a molded part comprises a method for producing a molding compound comprising I) a process for producing the molding compound, which comprises the following process steps: Step a) Providing lignocellulosic plants and / or lignocellulosic plant fibres; Step b) comminuting the lignocellulosic plants and / or lignocellulosic plant fibres; optionally, step c) involves obtaining lignocellulosic plant fibres from the comminuted lignocellulosic plants by separating the lignocellulosic plant fibres from the remaining components of the lignocellulosic plants; d2) mixing the shredded lignocellulosic plants and / or the shredded lignocellulosic plant fibres with a binder; and further the process for producing a molded part comprises the following process step II): e) shaping the molding compound obtained in d2) into a molded part.

[0018] Thus, the process for producing a molding compound, which is part of the process according to the invention for producing a molded part, comprises either as step d1) carrying out a partial delignification and hemicellulose hydrolysis or a step d2) which provides for a mixture with a binder.

[0019] Step c) of the process claimed in claim 1 is optional. If step c) is carried out, the subsequent steps involve lignocellulose-containing plant fibers alone or lignocellulose-containing plant fibers in combination with lignocellulose-containing plants.

[0020] In a preferred embodiment of the invention, the hop fibers are extracted in step c) by separating the hop fibers from the shives. This is achieved by separating the various components (fiber and shives) of the crushed hop vine material after step b) using a sieve and / or a vibrator, preferably a drum sieve.

[0021] If step c) is not carried out in the process according to the invention, there is no deliberate extraction of lignocellulose-containing plant fibers, but the lignocellulose-containing plants are subjected to the further process steps - without, for example, separating the hop vines from the hop fibers and shives.

[0022] In the process according to the invention, lignocellulose-containing plants and / or lignocellulose-containing plant fibers are provided, wherein these are preferably provided in step a) of the process according to the invention as dried lignocellulose-containing plants and / or dried lignocellulose-containing plant fibers.

[0023] The term "molding compound," as used herein, preferably encompasses a compound that, when pressed into a shape, produces a molded part, e.g., a plate or panel. Furthermore, the molding compound according to the invention can be used as a molded part in any desired shape and in various layer thicknesses.

[0024] The comminution of the hop fibers in step b) is preferably carried out using cutting mills, choppers, green waste chopper mills and / or rollers, preferably using a hammer mill.

[0025] For the sake of completeness, it should be noted that before step a) - the provision of the hop fibers - a first pre-crushing step usually takes place during the traditional hop harvest by the processing farms.

[0026] The approximately 7-meter-long vines are torn down and chopped into smaller pieces in the farmer's picking machine as part of the hop cone harvest.

[0027] The length of the vines can vary greatly, but due to their biological properties, the fibers are usually no longer than 1 meter, even if the vines are longer.

[0028] In a further embodiment of the invention, the lignocellulose-containing plants are plants of the Cannabaceae family. Preferably, the plants of the Cannabaceae family are hops, preferably hop vines, and / or other plants of the Cannabaceae family, preferably hemp.

[0029] The lignocellulose-containing plants are particularly preferably lignocellulose-containing plant fibres, with hop fibres being used preferably.

[0030] Hop fiber is a waste product in hop production. Hop fiber therefore offers a significant price advantage over other natural fibers.

[0031] In the traditional building materials sector, the production and use of materials such as concrete, steel, and even plastics generate significant CO2 emissions. Furthermore, many of these building materials are not recyclable at the end of their lifespan. The idea behind this invention is to use hop waste or byproducts of the hop harvest as a raw material for recyclable building materials instead of conventional building materials, thereby significantly reducing the emission of climate-damaging greenhouse gases.

[0032] Although planting and harvesting hops also requires a considerable amount of energy and water, hops are not cultivated for the production of molding compounds and molded parts, but rather for the further processing of the hop cones in the beer industry. Consequently, by using previously unused or neglected byproducts of the hop harvest as raw materials, the present description processes biomass that is already produced and does not consume additional resources in the form of energy, water, or land.

[0033] Securing the byproducts of hop harvesting is crucial, as it represents the beginning of the value chain. The logistical challenges of harvesting involve considering various criteria, such as the large amount of hop biomass generated, avoiding premature fermentation, drying the hop bines, shredding the remaining bines, separating the metal, and handling the bine chaff.

[0034] After harvest, the hop bine chaff begins to ferment rapidly due to its high moisture content. This poses the risk of releasing methane and CO2 emissions into the atmosphere, contributing to global warming.

[0035] In addition to CO2 emissions, the fermentation processes also negatively impact the quality of the hop fibers, as they are partially decomposed. Besides fermentation, mold growth also poses a problem for further processing.

[0036] According to common practice, a portion of the harvest is transported from hop growers to biogas plant operators. There, a portion is processed in biogas plants. However, these plants cannot process all of the unused biomass. Surplus is either spread on agricultural fields specifically designated for this purpose or distributed among the original hop fields. For cost reasons, the metal training wire is not separated from the hop vine. The simultaneous application of metal wire and vine chaff places unnecessary strain on the soil. In biogas plants, however, the metal wire is removed using a technical process before fermentation.

[0037] For example, to prevent fermentation and ensure safe storage of the vine chips, immediately after harvest the vine chips can be dried in drying containers using waste heat from the local biogas plant and then transported to a safe storage location.

[0038] In a particularly preferred embodiment, the method comprises method step d1) instead of d2).

[0039] The partial delignification of hop fibers, for example, serves to create a matrix bound by the lignin contained in the fibers. This process, described in d1), is based on the targeted chemical treatment of the hop fibers to partially dissolve the lignin and improve its binding properties without completely dissolving it.

[0040] Preferably, in step d1), the comminuted lignocellulose-containing plants and / or the comminuted lignocellulose-containing plant fibers are boiled with a combination of sodium hydroxide solution and hydrogen peroxide, or alternatively with a combination of sodium hydroxide solution and calcium hydroxide, with water preferably being added in both cases. Subsequently, the pH is preferably lowered to 4 to 5 by adding carboxylic acids and / or mineral acids, preferably acetic acid, nitric acid, and / or hydrochloric acid.

[0041] In a particularly preferred embodiment, the treatment in step d1) is carried out according to the following procedure: 1. The hop raw material (10 parts by weight) is treated with a combination of caustic soda (0.5-2 parts, preferably 1-1.5 parts) and hydrogen peroxide (1-5 parts, preferably 2 parts) or, alternatively, with a combination of caustic soda and calcium hydroxide (0.1-1 parts, preferably 0.2-0.4 parts), and in both cases with water (50-200 parts, preferably 100 parts) at a temperature of 70-120 °C, preferably 80 °C, for a period of up to 3 hours, preferably 1-1.5 hours. This alkaline step promotes partial delignification and prepares the fiber structure for subsequent binding. 2. The pH is then lowered to 4-5 by adding carboxylic and / or mineral acids, preferably acetic acid (1-5 parts, preferably 2-3 parts) and / or nitric or hydrochloric acid. This treatment is carried out at 70-120 °C, preferably 80 °C, for up to 90 minutes, preferably 30-45 minutes, to stabilize the lignin fragments and further condition the fiber structure. 3. The material can then be filtered through a sieve and / or filter bag and washed in water by immersing it in the water and turning it over. This ensures the removal of unwanted reaction byproducts.

[0042] Through partial delignification, the lignin contained in the fibers is chemically modified so that it continues to function as a natural binder, while the fibers retain their structural integrity. This enables the formation of a coherent matrix that can be processed into stable molded parts without the need for external binders.

[0043] Process d1) therefore utilizes the oxidative effect of hydrogen peroxide under alkaline conditions to cleave ether and carbon-carbon bonds in lignin. The subsequent pH reduction stabilizes the remaining lignin and optimizes it for fiber matrix formation. The use of preferably sodium hydroxide and optionally calcium hydroxide further contributes to fiber swelling, which further strengthens the mechanical bonding in the matrix.

[0044] To increase the efficiency of the separation, the entire process or individual steps can be repeated if necessary.

[0045] Hop fibers and water do not require the addition of binders, since a binder-free material is created after the molding compound has dried.

[0046] A noteworthy aspect is that when applying process step d1), no adhesive or binder needs to be added to the molding compound at any time. The adhesive in the molding compound is a compound derived from the hop vine's own lignin content.

[0047] Alternatively to step d1), the process may comprise a step d2) in which the plant components, preferably hop components, are mixed with a binder.

[0048] The above-mentioned process steps according to the invention may also comprise further intermediate steps, preliminary and / or subsequent steps.

[0049] The combination of the above-mentioned various parameters such as fiber length, chemical partial delignification, hemicellulose hydrolysis or, alternatively, the addition of one or more binders, enables the production of a wide range of products with a broad spectrum of properties such as hardness, extensibility, thermal and sound insulation, which finds its basis in the molding compound according to the invention.

[0050] The molding compound is shaped to produce a molded part. The molding compound is shaped in step e) preferably by injection molding or die-casting, and in a preferred embodiment, by a compression molding process, so that a molded part is obtained after the compression molding process.

[0051] The molding compound is preferably pressed and dried. The result is a board or panel that is very light, very porous, but also very stable, bonded by the lignin. This panel, after completing step d1), is characterized by its binder-free nature.

[0052] When combining hop fiber and lime, the hops are preferably pressed and dried with lime. The resulting board is robust and versatile. In a further embodiment of the invention, in step d2) an agent is used as binder which is selected from a group comprising lime, water glass, epoxy resin, clay, lignin, starch, casein and latex compounds, plastics such as preferably polylactides, mineral binders, either individually or any combination thereof.

[0053] In a further embodiment of the invention, the mixing ratio between the comminuted lignocellulose-containing plants and / or the comminuted lignocellulose-containing plant fibers and the binder is 20:1 to 1:1.

[0054] If the lignocellulose-containing plants are hops, preferably hop vines, the said mixing ratio of the shredded lignocellulose-containing hop vines and / or the lignocellulose-containing hop fibers to the binder is from 20:1 to 1:1. Preferably, the mixing ratio of the shredded lignocellulose-containing hop fibers to the binder is from 20:1 to 1:1.

[0055] In a further embodiment of the invention, at least the most extensive removal of impurities takes place before step a), in step a), or after step b). The impurities can be, for example, metal wires used in hop cultivation. The removal of the impurities is preferably carried out by magnetic separation and / or sedimentation.

[0056] In a further embodiment of the invention, the comminution of the lignocellulose-containing plants in step b) is carried out to a fiber length between 0.5 mm and 100 cm, preferably to a fiber length between 0.5 mm and 25 cm, particularly preferably between 0.5 cm and 15 cm.

[0057] In a further embodiment of the invention, the molding compound is shaped into the molded part by placing the molding compound into a mold frame and pressing the molding compound contained in the mold frame. The pressing is carried out with a pressure preferably between 1 and 20 tons.

[0058] In a further embodiment of the invention, the partial delignification and hemicellulose hydrolysis in step d1) further comprises a filtration and / or washing step. This filtration and / or washing step is preferably carried out using a sieve or a filter bag.

[0059] In a further embodiment of the invention, the mineral acid used in step d1) is acetic acid.

[0060] In a further embodiment of the invention, the molded part is a cladding part, a furnishing for a building or building component, a filler, a coating, an insulating material or a building material. The building material is preferably an acoustic insulation material, a building board or a thermal insulation material.

[0061] Particularly noteworthy are the good sound absorption values ​​of the molded parts according to the invention.

[0062] When testing panels made of hops according to the invention, an absorption value of 0.55 Aw was achieved. This puts the panel according to the invention at the average level for commercially available and unsustainable synthetic absorbers, such as Basotect from BASF.

[0063] The Aw value represents the weighted sound absorption coefficient, which is determined according to ISO 11654. Aw = 0 means no absorption occurs—all incident sound is reflected. At Aw = 1, all incident sound is absorbed; no reflection occurs.

[0064] Initial flammability tests have already been conducted with hop vine chips at the PÜZ Fire Protection Testing Center at the Technical University of Munich. The preliminary tests resulted in building material class B2 according to DIN 4102-1, indicating normal flammability. Hops, as a natural plant without any additional additives, thus already achieve the required building material class for comparable products on the market in the areas of acoustics and thermal insulation. In terms of thermal conductivity, the hop vine chips achieved a value of 0.053-0.058 W / (mK) after initial preliminary tests at the IFT Rosenheim, making them comparable to wood fiber and straw insulation and providing better insulation than reed or wood wool insulation.

[0065] The sound absorption value of the hop panel according to the invention is therefore already at the level of commercially available synthetic absorbers.

[0066] The components according to the invention also meet the required standards with regard to flammability, thermal conductivity and fire protection class. ExamplesExample 1: Hops + inventive process

[0067] In a first step (a), the harvested hop material was prepared and dried in a kiln drying system. In a first step (b), the prepared hop material was shredded with a green waste chopper. Subsequently, the dust and impurities were removed using a drum sieve and a magnetic separator and filled into big bags.

[0068] 500 g of the obtained material was then boiled with 50 g NaOH, 10 g Ca(OH)2, and 5 liters of water at 80 °C for 1.5 hours. The pH was reduced to 4 by adding and boiling with 150 ml of acetic acid at 80 °C for 45 minutes. The material was placed in a filter net and then washed in three cycles in 5 liters of water for 5 minutes each.

[0069] The matrix was then filled into a negative mold, pressed into a plate under 5 tons of pressure and dried in air until dry. Example 2: Hops + inventive process

[0070] In a first step (a), the harvested hop material was prepared and dried in a kiln dryer. In a first step (b), the prepared and dried hop material was shredded with a green waste chopper. Subsequently, the dust and impurities were removed using a drum sieve and a magnetic separator and filled into big bags.

[0071] 500 g of the obtained material was boiled with 75 g NaOH, 200 g H2O2, and 5 liters of water at 80 °C for 1 hour. The pH was reduced to 5 by adding 100 ml of acetic acid and boiling at 80 °C for 45 minutes. The material was placed in a filter mesh and then washed in three cycles in 5 liters of water for 5 minutes each. The matrix was then filled into a negative mold, pressed into a plate under 5 tons of pressure, and air-dried until dry. Table 1: Comparison of the panels according to the invention compared to commercially available panels Comparison criteria Category Acoustic panels made from agricultural hop waste products according to the invention Whisper wool - acoustic panels made from sheep's wool, wool felt and binding agents Hemp - acoustic panels made of hemp and binding agent DeVorm - Acoustic panels made from partially recycled PET and binder WoodU p - Akusti kpan eele made of felt and recycled m PET, glued Stramen T ec - Drywall elements made of straw Basotec t (BASF) - Acoustic element made of melamine resin foam with fabric covering Sound insulation class / αW value according to DIN EN ISO 11654 Effectiveness C / 0.55 (at 40mm thickness) D / 0.35 (at 12mm thickness) D / 0.55 (at 20mm thickness) D / 0.25 (at 10mm thickness) D / 0.3 (at 22mm thickness) No sound absorber (sound insulation 42DB+) C / 0.6 (at 40mm thickness) Fire protection class for building materials Effectiveness B2 normal entflam mb ar F easily flammable B1 severely flammable unknown unknown Fire protection wall F90 B1 severely flammable Completely biodegradable Sustainability Yes, according to procedure step c) Conditional No No No Yes No Bio-based binding agents Sustainability Yes, plants tend to use lignin No No No No Yes Yes Variety free Sustainability Yes No No Yes No Yes Conditional Separation possible since Recyclin g: Cradleto Cradle without Downcyclin 9 Sustainability Yes Yes No No No Yes No No additional resource consumption Sustainability Yes Yes No No No No No CO2-negative v Sustainability Conditional No Conditional No No Conditional No

[0072] Panels according to the invention guarantee industry-standard performance with regard to all structural material properties such as sound absorption or fire protection class.

[0073] The use of bio-based and water-soluble binders ensures the reuse of raw materials after the product's lifetime.

[0074] Building materials can thus be returned to a new life cycle after their useful life without any loss of quality or resources by being incorporated as starting material directly after prior comminution in step c) (optional) or in step d1) or d2) of the process.

[0075] The molding compounds and molded parts according to the invention are made from a renewable raw material. They extract carbon dioxide from the atmosphere and store it permanently, while also avoiding CO2 emissions by preventing the hop waste from fermenting in open fields. Example 3: Hops + binding agent (steps a) + d)) Table 2: Material samples and their recipes Material sample hop binder Water A ratio 200 g hops 2 2 100 g latex milk 1 - B ratio 400 g hops 3 1 1,200 g lime 3 1.800 g 4,5 C ratio 400 g hops 1 1 1,200 g lime 3 1.200 g 3 D ratio 250 g hops 2 1 750 g lime 3 750 g 3 E ratio 300 g hops 1 1 900 g clay 3 600 g 2 F ratio 300 g hops 2 1 1,200 g clay 4 600 g 2

[0076] After step b), the crushed hop bines were mixed with binders and water as step d2). Step d1) according to claim 1 was therefore not performed. The mixing ratios can be found in the table.

[0077] The material was mixed by hand and then mechanically pressed with 5 tons of pressure and then dried at room temperature for several days. Character list Fig. Figure 1 shows a photo of panels obtained using the process according to the invention. Fig. Figure 2 shows a schematic representation of the mixture of hops with a binder. Fig. Figure 3 shows a photograph of material samples according to the invention with clay, lime and natural latex, whereby the ratio of hops, binder and water of the panels A to F can be seen from Table 2. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 31 05 596 C2

[0007] DE 23 19 759 A

[0007] DE 10 2004 012 458 B4

[0007] EP 2 193 899 A1

[0007] US 5,076,986

[0007]

Claims

[1] A process for producing a molded part comprising a process for producing a molding compound, the process for producing the molding compound comprising: (a) providing lignocellulosic plants and / or lignocellulosic plant fibres; b) comminuting the lignocellulosic plants and / or lignocellulosic plant fibres; optionally c) obtaining lignocellulosic plant fibres from the comminuted lignocellulosic plants by separating the lignocellulosic plant fibres from the remaining components of the lignocellulosic plants; d1) carrying out a partial delignification and hemicellulose hydrolysis, wherein the partial delignification and hemicellulose hydrolysis in step d1) comprises the following steps: - cooking the comminuted lignocellulosic plants and / or the comminuted lignocellulosic plant fibers in an agent selected from a group comprising sodium hydroxide, hydrogen peroxide, calcium hydroxide, either individually or any combination thereof; - treating the comminuted and cooked lignocellulosic plants and / or the comminuted and cooked lignocellulosic plant fibers with an agent selected from a group comprising carboxylic acid, mineral acid, either individually or a combination thereof; or d2) mixing the shredded lignocellulosic plants and / or the shredded lignocellulosic plant fibres with a binder; and further the method for producing a molded part comprises: e) shaping the molding compound obtained in d1) or d2) into a molded part. [2] A method for producing a molded part according to claim 1, wherein the molded part is a cladding part, a furnishing article for a building or building component, a filler, a coating, an insulating material or a building material, wherein the building material is preferably an acoustic insulation material, a building material panel or a thermal insulation material. [3] A process for producing a molded part according to claim 1 or claim 2, wherein the lignocellulose-containing plants are plants of the Cannabaceae family, preferably hops and / or hemp. [4] A process for producing a molded part according to any one of claims 1 to 3, wherein in step d2) the binder is an agent selected from a group comprising lime, water glass, epoxy resin, clay, lignin, starch, casein and latex compounds, plastics such as preferably polylactides, mineral binders, either individually or any combination thereof. [5] The method according to claim 4, wherein the mixing ratio between the comminuted lignocellulose-containing plants and / or the comminuted lignocellulose-containing plant fibers and the binder is 20:1 to 1:

1. [6] Method according to one of claims 1 to 5, wherein in step a) or after step b) interfering components are removed at least to the greatest extent possible, wherein the removal of the interfering components is preferably carried out by means of magnetic separation and / or sedimentation. [7] Process according to one of claims 1 to 6, wherein the comminution of the lignocellulose-containing plants in step b) is carried out to a fiber length between 0.5 mm and 25 cm. [8] Method according to one of claims 1 to 7, wherein the shaping is carried out by placing the molding compound into a mold frame and pressing the molding compound contained in the mold frame with a pressure of preferably between 1 and 20 tons. [9] Process according to one of claims 1 to 8, wherein the partial delignification and hemicellulose hydrolysis in step d1) further comprises a filtration and / or washing step, said filtration and / or washing step preferably being carried out by means of a sieve or a filter bag. [10] Process according to one of claims 1 to 9, wherein the mineral acid in step d1) is an acetic acid.

Images