WO2013076960A1 - Biomass powder derived from oil palm and production method therefor, and biomass-composite molded body and production method therefor - Google Patents

Abstract

Provided are a biomass powder derived from oil palm that is suitable as a homogeneous fibrous raw material for industrial use, and a composite molded body using said biomass powder that exhibits superior mechanical properties. On a differential curve representing thermal weight reduction, the biomass powder derived from oil palm does not have a peak in the temperature range of 180-320°C and does have a peak in the temperature range of 300-400°C. 50 mass% or more of the biomass powder has a major axis length in the range of 1-500 µm. The biomass-composite molded body is made by molding a composition containing the biomass powder and a prepolymer of a thermoplastic resin or a thermosetting resin at a mass ratio of 5:95-80:20.

Description

Oil palm derived biomass powder and method for producing the same, biomass composite molded body and method for producing the same

The present invention relates to a technology for utilizing biomass derived from oil palm that is abundant in tropical regions and insufficiently used.

Oil palm oil is collected from mesocarp and endocarp. Since the amount of fats and oils obtained per planted area is one of the best among plants, it is cultivated on a large scale by plantation farming methods in tropical regions, especially Malaysia and Indonesia. The mature palm oil consists of a single trunk (trunk) and reaches a height of 20m. The foliage is called Frond and has a feather shape of about 3 to 5 meters long. About 30 young trees grow and about 20 new trees grow 10 years or older per year. The fruit of oil palm is called a fresh fruit bunch (hereinafter abbreviated as FFB), and one FFB is a collection of about 200 eggs. The weight is about 40-50kg per cell.
Each fruit of FFB consists of a fleshy mesocarp with a lot of oil and a single fruit shell that is also rich in oil. The mesocarp portion after squeezing the oil from the berries is rich in cellulose fiber and is called mesocarp fiber (hereinafter abbreviated as MF). Moreover, the empty bunch after removing the berries is referred to as an empty fruit bunch (hereinafter abbreviated as EFB).

The biomass discharged from the plantation is enormous, and it is said that annual emissions of over 10 million tons of each of Frond, MF, and EFB. These biomass are reused in plantation and palm oil production processes. For example, front is spread on the base of oil palm and used as fertilizer, and MF is used as fuel for palm oil mills. Although frontal and MF are rich in high-quality cellulose fibers, the use of these enormous amounts of biomass is limited.

For example, as a method of using MF and front, a method of collecting pulp and organic acid-modified lignin by digesting MF and front in the presence of acid (see Patent Document 1), and thermosetting a fiber mat mainly composed of palm fiber After adhering with a functional resin, a heat insulating material for interiors obtained by compression molding (see Patent Document 2), a compression molded body such as a pallet or a tray (see Patent Document 3), and further MF is radiation and / or high-pressure steam. Only a method of using it as a feed after being sterilized in the presence (see Patent Document 4) is disclosed.
In addition, EFB derived from the same oil palm fruit is converted to biomass ethanol (see Patent Document 5), heat insulating wall structure (see Patent Document 6), molded board (Patent Document), in addition to the same method of use as MF and Frond. 7) and other industrial product materials.

There are several problems when using front, MF and EFB as industrial fiber materials. For example, it contains a large amount of water, the composition and shape are inhomogeneous, and the odor component volatilizes during heating.
By solving these problems, it is possible to effectively use these enormous amounts of biomass as industrial fiber materials with higher added value.

As a method for efficiently dehydrating and drying from biomass derived from oil palm, there is disclosed a method of treating in oil at 120 to 300 ° C. under a pressure higher than the saturated vapor pressure of the oil at that temperature (see Patent Document 8). ). However, this technique is a method for converting biomass into fuel, and it is not a suitable drying method because it requires a deoiling process to make it an industrial material.

In order to make the heterogeneous composition and shape more uniform, there are methods of chemically separating the components or finely pulverizing and mixing them to make them physically homogeneous.
As a chemical method, for example, in the case of EFB, cooking using caustic soda or the like is used (see Patent Document 9). When components are separated by chemical treatment, a waste liquid in which a lignin component called black liquor is dissolved is discharged, and the treatment is also a problem. As a physical homogenization method, a technique in which a soft component such as a leaflet in a foliage is mechanically pulverized and dried by a method such as freeze-drying is disclosed (Patent Document 10). reference). However, fibrous biomass such as EFB is not easily crushed and pulverized by a mechanical method because of its strong fiber structure.
By the way, it is about green composite development using bamboo fiber, but as a method of taking out bamboo fiber, scorpion bamboo is repeatedly pulverized many times to obtain long fiber, and then fibrillated with a mixer to obtain bamboo single fiber A method and a method of obtaining bamboo fiber by combining an alkali treatment with an explosion treatment are disclosed. And it is supposed that the strength improvement of the composite obtained can be aimed at by carrying out the hot press process of the preform of the bamboo fiber obtained by these methods (refer nonpatent literature 1).
However, since the structure of bamboo and the structure of oil palm are greatly different, it is unclear whether a desired effect can be obtained when this bamboo technique is applied to oil palm.

The unique odor that is generated when oil-derived biomass is heated is based on pyrolyzed and vaporized components. Biomass is usually composed of cellulose, hemicellulose, and lignin. Among these main components, hemicellulose is easily decomposed at the lowest temperature (see Non-Patent Document 2), and generates volatile substances such as acetic acid and formic acid. This decomposition of hemicellulose has a peak in the temperature range of 180 to 320 ° C., and overlaps with the melt molding temperature of general thermoplastics. Therefore, when the biomass and the thermoplastic are blended and heated to around 200 ° C., the hemicellulose component is decomposed and a specific odor is emitted.

In addition, as a method of utilizing oil palm-derived biomass as a fiberboard having good moisture permeability and high strength without particularly homogenizing, flexibility of EFB fiber component of 100 to 600 μm in diameter and 5 to 30 cm in length A method is disclosed in which a highly rigid material is defibrated, a thermosetting resin is added as an adhesive component, and compression molding is performed in a temperature range of 100 to 200 ° C. (see Patent Document 11). However, with this method, it is difficult to efficiently obtain a molded body having a complicated shape.

JP 2006-112004 A Japanese Patent Laid-Open No. 10-138210 Special table 2008-502517 JP 09-168367 A JP 2009-125050 A Japanese Patent Laid-Open No. 10-183797 Japanese Patent Laid-Open No. 06-285819 Special Table 2004-209462 Special table 2010-090487 JP 2005-218425 A JP 2000-006116 A

The first problem to be solved is that conventional oil palm-derived biomass has a high moisture content, has a heterogeneous composition and shape, and is difficult to use as it is as an industrial fiber material. is there.

In addition, the second problem to be solved is that it is difficult to make fine powder when the oil palm-derived biomass and the resin are combined, and the characteristics of the thermoplastic resin are reduced due to the generation of odor components accompanying thermal decomposition. It is difficult to make use of melt injection molding and extrusion molding.

The biomass powder derived from oil palm according to the present invention does not have a peak in the temperature range of 180 to 320 ° C. in the differential curve of thermogravimetry, has a peak in the temperature range of 300 to 400 ° C., and is 50% by mass or more. The major axis is in the range of 1 to 500 μm.

The oil palm-derived biomass powder according to the present invention is preferably characterized in that the raw material is a fibrous residue (MF) after squeezing oil from the mesocarp of oil palm.

Also, the oil palm-derived biomass powder according to the present invention is preferably characterized in that the raw material is a fiber residue (front fiber) after squeezing the sugar component from the oil palm stems and leaves.

Also, the oil palm-derived biomass powder according to the present invention is preferably characterized in that the raw material is an empty bunch after removing the fruit from the oil palm fruit.

The method for producing biomass powder according to the present invention is the method for producing biomass powder described above, characterized in that the raw material is treated with steam at 170 to 250 ° C. for 10 minutes to 6 hours and then pulverized. To do.

The biomass composite molded body according to the present invention is formed by molding a composition containing the biomass powder and a thermoplastic resin or a prepolymer of a thermosetting resin in a mass ratio of 5:95 to 80:20. .

Also, the method for producing a biomass composite molded body according to the present invention is characterized in that a biomass composite molded body is obtained by melt molding.

Further, the method for producing a biomass composite molded body according to the present invention is characterized by molding by an injection molding method or an extrusion molding method.

Since the biomass powder according to the present invention has 50% by mass or more in the range of the major axis of 1 to 500 μm, it can be used as a physically homogeneous industrial fiber material. Moreover, the mixture with a thermoplastic resin can be applied to a molding method capable of obtaining a complicated molded body such as injection molding or extrusion molding. At this time, since the biomass powder does not have a peak in the temperature range of 180 to 320 ° C. and has a peak in the temperature range of 300 to 400 ° C. in the differential curve of thermogravimetry, It is possible to reduce the amount of the odor component generated by the decomposition of the hemicellulose component.
Moreover, the biomass powder manufacturing method according to the present invention can suitably obtain the biomass powder according to the present invention.
In addition, the biomass composite molded body according to the present invention is obtained by molding a composition containing a fibrous biomass powder and a thermoplastic resin in a mass ratio of 5:95 to 80:20. An excellent composite molded body can be suitably obtained.
In addition, the method for producing a biomass composite molded body according to the present invention can suitably obtain the biomass composite molded body according to the present invention.

FIG. 1 is an optical micrograph of the mesocarp fiber powder produced in biomass powder production Example 2. FIG. 2 is a long diameter size distribution diagram of the mesocarp fiber powder produced in biomass powder production Example 2. FIG. 3 a is a thermogravimetric reduction curve (TG) of the mesocarp fiber powder produced in biomass powder production Examples 1 and 2 and Comparative Example 1. FIG. 3 b is a thermogravimetric decrease derivative curve (DTG) of the mesocarp fiber powder produced in biomass powder production Examples 1 and 2 and Comparative Example 1. FIG. 4 is an optical micrograph of the foliage fiber powder produced in biomass powder production Example 3. FIG. 5 is a major axis size distribution diagram of the foliage fiber powder produced in biomass powder production Example 3. FIG. 6 a is a thermogravimetric reduction curve (TG) of the foliage fiber powder produced in biomass powder production Example 3 and Comparative Example 2. FIG. 6 b is a thermogravimetric decrease derivative curve (DTG) of the foliage fiber powder produced in biomass powder production Example 3 and Comparative Example 2.

An embodiment of the present invention (hereinafter referred to as the present embodiment) will be described below.
Oil palm (Elaeis) is a collective term for plants classified into the genus Acapulaceae, 2 of Guinea oil palm (Elaeis guineensis) native to West Africa and America oil palm (Elaeis oleifera) native to the tropical region of Central and South America. The seed is known. In the embodiment of the present invention, the type of oil palm to be used is not limited.
Further, in the embodiment of the present invention, the oil palm means a total consisting of a trunk (trunk), foliage (Frond), fruit (FFB), mesocarp (mesocarp), fruit shell (shell), In particular, MF, which is a component rich in cellulose fiber after squeezing oil from mesocarp, and fiber front fiber after squeezing sugar component, and empty bunch after removing fruit from fruit (EFB) ) Is suitable as a raw material for the biomass powder of the present embodiment.

Oil palm-derived biomass consists of cellulose, hemicellulose, and lignin as its main components.
Hemicellulose plays the role of an adhesive that binds cellulose and lignin or cellulose. For example, when the biomass powder is blended with a resin and molded at a high temperature, the hemicellulose not only degrades the physical properties of the blend but also causes deterioration of the working environment.
The biomass powder of the present embodiment is chemically a mixture of cellulose, lignin and hemicellulose as main components, and further includes a mixture of silica fine particles as other trace components.

The biomass powder of the present embodiment does not have a peak in the temperature range of 180 to 320 ° C. and has a peak in the temperature range of 300 to 400 ° C. in the differential curve of thermogravimetry. The differential curve of thermogravimetry is measured by mechanically differentiating the thermogravimetric curve measured at 10 ° C / min in nitrogen using a differential thermal gravimetric analyzer (Differential Thermal Gravimetrical Analyzer). Can do.
In the differential curve of thermogravimetry, the peak in the temperature range of 180 to 320 ° C. is based on the decomposition of hemicellulose, and the biomass powder of the present embodiment has substantially no peak in this temperature range. Means that the biomass powder does not contain hemicellulose or that the hemicellulose content is below the detection limit of the differential thermogravimetry apparatus. The peak in the temperature range of 300 to 400 ° C. is based on the decomposition of cellulose, and the fact that the biomass powder has a peak in this temperature range indicates that the biomass powder contains cellulose.
That is, the biomass powder of the present embodiment is rich in the cellulose component, and the hemicellulose component is not detected by the measurement method.

The biomass powder of the present embodiment has a short fiber shape.
In the biomass powder of the present embodiment, 50% by mass or more is in the range of the major axis of 1 to 500 μm. Here, the major axis means the major axis diameter of the short fibrous particles. The mass ratio of the particles having a major axis in the range of 1 to 500 μm is assumed to be the same as the mass ratio by assuming that the shape of the short fiber biomass powder particles is an ellipsoid and the specific gravity is constant. From the measurement of the major axis diameter a and the minor axis diameter b by microscopic observation, it can be obtained by measuring the major axis and mass of the measurement particles according to the following formula. Here, π is the circumference ratio.
Volume V = 4πab ^2/3
The approximate value of the mass ratio of particles having a major axis in the range of 1 to 500 μm can also be easily obtained by a sieving method.
The biomass powder is preferably 80% by mass or more, and more preferably 90% by mass or more, in the above-mentioned major axis range. The biomass powder preferably has a major axis of the above-mentioned content of powder in the range of 10 to 250 μm, more preferably in the range of 50 μm to 150 μm.
When the biomass powder contains particles having a major axis exceeding 500 μm, when used as a raw material for a composite material with a thermoplastic resin, the melt fluidity may be hindered during melt molding of the thermoplastic resin. At this time, if the content of the biomass powder in the range of 1 μm to 500 μm is less than 50% by mass, the fluidity of the mixture is inhibited when the biomass powder is mixed with a resin and heated and melt-molded. May get stuck inside the screw. On the other hand, when the biomass powder contains particles having a major axis of less than 1 μm and the number of extremely small powders increases, handling becomes difficult. In particular, in the injection molding that requires fluidity of the molten resin composite, the content of biomass powder in the range from 1 μm sieve to 500 μm sieve is 90% by mass or more, more preferably 95% by mass or more. Is desirable.

The biomass powder of the present embodiment described above can be used as a physically homogeneous industrial fiber material. Moreover, the mixture with a thermoplastic resin can be applied to a molding method capable of obtaining a complicated molded body such as injection molding or extrusion molding. At this time, since the biomass powder does not have a peak in the temperature range of 180 to 320 ° C. and has a peak in the temperature range of 300 to 400 ° C. in the differential curve of thermogravimetry, It is possible to reduce the amount of the odor component generated by the decomposition of the hemicellulose component.

Below, the manufacturing method of the biomass powder of this Embodiment which can obtain the biomass powder of this Embodiment suitably is demonstrated.
In the method for producing biomass powder according to the present embodiment, a raw material derived from oil palm is treated with steam at 170 to 250 ° C. for 10 minutes to 6 hours, and then pulverized to a desired size. Here, the raw material derived from oil palm is itself a biomass, but is referred to as a raw material in order to distinguish it from the obtained biomass powder of the present embodiment.

Treatment means bringing steam heated to 170 to 250 ° C. into contact with biomass. When the temperature is less than 170 ° C., the steam treatment effect, that is, the degree of decomposition of the low-temperature decomposition component mainly composed of hemicellulose in the raw material is small, and the treatment takes a long time. Furthermore, as will be described later, 170 ° C. is a reverse transition temperature, and therefore, a drying treatment can be simultaneously performed above that temperature. On the other hand, when the temperature exceeds 250 ° C., decomposition of the raw material tends to proceed more than necessary and carbonization tends to occur, which is not preferable. The heating steam treatment temperature is more preferably in the range of 190 to 240 ° C., further preferably 200 to 230 ° C.

Here, the water vapor at 170 to 250 ° C. is water vapor in the temperature range of 170 to 250 ° C. in the pressure range from the saturation pressure to the normal pressure. Such steam includes atmospheric superheated steam and pressurized saturated steam. Normal pressure superheated steam is different from pressurized saturated steam obtained by heating in a constant volume state, and is obtained by further heating 100 ° C steam in a state where it can expand, Say.

The advantage of pressurized saturated steam is that it is pressurized, so (1) the water molecule concentration in the steam is high, the reaction is fast and can be processed in a short time, and (2) the steam is in the pressure vessel during the reaction. Since it is held and not released, the utilization efficiency of water vapor is high. On the other hand, the merit of normal pressure superheated steam is that the pressure is normal pressure, (1) when using a reaction vessel, for example, the pressure resistance of the vessel is unnecessary, and (2) scale-up is easy. Further, (3) the component decomposed and removed by the atmospheric superheated steam is discharged on the steam flow, and therefore, for example, when using a reaction vessel, the decomposition vaporized product is not liquefied and retained in the reaction vessel. Furthermore, (4) at a temperature higher than the reverse transition temperature of water at 170 ° C., the drying rate of the processed product is faster than that of dry air, so that a drying step for the product after processing is unnecessary.
Both pressurized saturated steam and atmospheric superheated steam have different merits as described above. Therefore, according to other conditions (processing amount, processing time, discharge conditions of decomposition products, etc.) It can be selected between pressurized saturation and normal pressure overheating. In the case of treating a large amount of biomass, a normal pressure superheated steam treatment and a steam treatment under slightly pressurized conditions using a pressure damper are more preferable treatment methods. Furthermore, when carrying out drying of biomass at the same time, a normal pressure superheated steam treatment at a reverse transition temperature (170 ° C.) or higher is a more preferable treatment method.

Heated steam treatment can be performed by placing a raw material derived from oil palm in a reaction vessel and introducing water vapor into the reaction vessel. In this case, the raw material is cut into dimensions that can be accommodated in the reaction vessel. If a large-sized normal pressure reaction vessel is used, the cutting of the raw material is substantially unnecessary. Further, the heating steam treatment may adopt a method in which biomass is placed on a continuous conveyor and moved and sprayed with atmospheric superheated steam. In this case, cutting of the raw material is substantially unnecessary, and continuous Processing efficiency is high by processing. Furthermore, the method in which the heated steam treatment is performed by spraying heated steam in a rotary kiln, in which case the contact between the raw material and the steam becomes more uniform, and further, the raw material is crushed and crushed simultaneously in the apparatus. Since it can also be performed, processing efficiency is high.

The heating steam treatment time varies depending on whether pressurized saturated steam or normal pressure steam is used, and at what temperature the treatment temperature is used. In the case of using pressurized saturated steam, it is preferably selected in the range of 30 minutes to 4 hours including the pressurization temperature raising and pressure reduction temperature lowering processes. On the other hand, when normal pressure superheated steam is used, the reaction progress is slower than that of pressurized saturated steam, but since a pressure increasing / decreasing process is unnecessary, it is preferably selected in the range of 30 minutes to 7 hours. Among these, the net steam treatment time is 10 minutes to 3 hours when using pressurized saturated steam, 30 minutes to 6 hours when using atmospheric superheated steam, and more preferably 1 to 3 hours. .

The raw material derived from the oil palm after the heat treatment can be easily pulverized because the easily degradable hemicellulose is preferentially decomposed and a part thereof is removed as a volatile component. The crushing and pulverization performed as necessary before pulverization can be performed using an appropriate apparatus. At this time, a two-stage process in which fine pulverization is performed after coarse pulverization may be performed. As an apparatus used for pulverization, a generally known crushing and pulverizing apparatus can be used. Examples of suitably used crushing apparatuses include, for example, hammer mill, cutter mill, pin mill, crusher mill, ball mill, rod mill, bar mill, disk mill, blade mill, vibration mill, and a combination of these individual methods. Is the method.

The biomass powder immediately after pulverization can be used as it is as the biomass powder of the present embodiment, but it is preferable to control the particle size distribution by classification operation in order to develop more advanced characteristics. As a method used for the classification operation, a generally known classification method can be used without any limitation. Examples of suitable classification methods include sieve classification, airflow classification, vortex centrifugal classification, electrostatic separation classification, and the like, and various loads such as ultrasonic waves, longitudinal and transverse vibrations, and the like. There are combined classification methods. Specifically, a vibration classifier, a cyclone, an air classifier, a rotary drum type electrostatic separator, and the like are suitable classifiers. The biomass powder of this Embodiment can be suitably obtained using these apparatuses.

The method for producing biomass powder according to the present embodiment described above is substantially safe and simple without any chemical treatment operation using alkaline or acidic substances and without post-treatment of the used chemical substances. By this method, the biomass powder of the present embodiment can be suitably obtained.

Next, the biomass composite molded body of the present embodiment will be described.
The biomass composite molded body of the present embodiment is formed by mixing (1) biomass powder of the present embodiment and (2) a prepolymer of a thermoplastic resin or a thermosetting resin and melt-molding it. The mass ratio of the biomass powder and the prepolymer of thermoplastic resin or thermosetting resin is biomass powder: prepolymer of thermoplastic resin or thermosetting resin = 5: 95 to 80:20, preferably 10:90. 60:40, more preferably 20:80 to 55:45. When the ratio of the biomass powder is less than 5, the effect of adding the biomass powder is not clearly expressed. Moreover, in the ratio exceeding 80, it is easy to cause the fall of the mechanical strength of a biomass composite molded object.

The thermoplastic resin can be used without any limitation as long as it can be combined with biomass powder. Examples of suitable thermoplastic resins include polyolefins such as polyethylene and polypropylene; polystyrene, acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene (AS) resin, methyl methacrylate-butadiene-styrene (MBS) resin Styrenic resins such as: Aromatic polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polylactic acid, polycaprolactone, poly (3-hydroxybutyric acid), polytetramethylglycolide, polyglycolic acid, etc. Examples include aliphatic polyesters. Among these thermoplastic resins, polyolefins are particularly preferable from the viewpoint of ease of molding. These thermoplastic resins may be used alone or in combination of two or more.

In addition to the thermoplastic resin, a thermoplastic prepolymer of a thermosetting resin can be used. Typical prepolymers of thermosetting resins include prepolymers such as epoxy resins, unsaturated polyester resins, silane-crosslinked polyethylene, alkyd resins, melamine resins, polyurethane, and crosslinked rubber. Among these prepolymers of thermosetting resins, prepolymers such as epoxy resins, polyurethanes, and unsaturated polyester resins are preferable because they can be easily combined with the biomass powder according to the present invention.

A known method can be used without any limitation as long as the biomass powder and the thermoplastic resin are mixed and melt-molded as long as the biomass powder can be uniformly dispersed in the thermoplastic resin.
For example, a melt kneading method in which a thermoplastic resin is melted by heat and kneaded while applying shear stress to the biomass powder, a solution in which the thermoplastic resin is dissolved in a solvent, and the biomass powder is added and dispersed, and then the solvent is vaporized and removed. There are a mixing method, a calender molding method in which a thermoplastic resin is softened on a heated roll, a biomass powder is added thereon, and kneaded while being pressed by a hot roll. Among these compounding methods, the melt-kneading method is most preferable in terms of efficiency and versatility.

Specific examples of the melt-kneading method include an injection molding method using an injection molding machine, an extrusion molding method using an extrusion molding machine, and a blow molding method using a blow molding machine. Using the formed sheet-shaped body, a vacuum molding method using a vacuum molding machine, a compression molding method using a compression molding machine, or the like is preferably used. Among these molding methods, the injection molding method and the extrusion molding method are more preferably used from the viewpoints of versatility and expandability.

Injection molding is a method of obtaining a molded product by injecting and injecting a heat-melted material into a mold cavity, and cooling and solidifying the material. Through the parts called sprue and runner, The mold cavity is filled with a molten biomass-containing resin melt. Here, since the biomass powder does not melt, a thermoplastic resin excellent in fluidity is selected when performing injection molding that requires melt fluidity.

Extrusion molding is a molding method in which a material melted and mixed by shear stress and heat generated by the rotation of a screw in a heated cylinder is cooled and solidified while being extruded from a die extrusion port at a constant speed. Since high fluidity like injection molding is not required, a high-molecular weight thermoplastic resin having a high viscosity so as not to be deformed after being extruded from the extrusion port is selected. Furthermore, in extrusion molding, kneading with a screw is effectively performed. There are various screw shapes and directions of rotation, which can be selected according to the purpose of use. In the production of the biomass composite molded body of the present invention, in order to further increase the kneading degree, kneading with a biaxial co-rotating screw is a more preferable method.

In the method for producing a biomass composite molded body according to the present embodiment, for example, when a biomass composite molded body is molded using an injection molding machine, high melt fluidity is required, and before filling into a mold, a screen is used. Insoluble substances having a large size are collected through the filter, so that it is more effective that the biomass powder is distributed more in the relatively small particle size. On the other hand, when a biomass composite molded body is molded using extrusion molding, a biomass powder containing a long fibrous component is oriented and flows in a molten thermoplastic resin. Therefore, as a result, a composite molded body containing an oriented fibrous biomass powder is obtained, which is an embodiment of a suitable production method in which an improvement in mechanical properties due to fiber reinforcement is easily expressed.

In addition, since the biomass powder according to the present embodiment is obtained by reducing in advance the hemicellulose component that is easily decomposed by steam treatment, it is effective to generate odor accompanying decomposition during melt molding with the thermoplastic resin. Has been reduced. Further, in order to eliminate odor, it is possible to selectively exclude volatile products from a vent installed in a cylinder of a melt molding machine during melt molding, which is one of preferred embodiments.

In the case of using a thermosetting resin prepolymer instead of the thermoplastic resin, the above-described production method can be used. At this time, the biomass powder and the thermosetting resin prepolymer, and if necessary, a curing agent are used. A biomass composite molded article having excellent mechanical strength can be obtained by melt-molding the mixed composition under conditions where the curing reaction does not proceed, and then curing the mixture by stimulation such as heating, water vapor, or light irradiation.

The biomass composite molded body excellent in melt moldability and mechanical properties can be efficiently obtained by the method for producing a biomass composite molded body of the present embodiment described above. The biomass composite molded body obtained by the method for manufacturing a biomass composite molded body according to the present embodiment is used as a synthetic wood material for various housing and building materials, and for various melting of home appliance / IT equipment parts and automobile interior parts. It can use suitably for the use of a molding.

Hereinafter, the present invention will be specifically described by way of examples. However, these examples do not limit the scope of the present invention.

(Examples 1 and 2 for producing biomass powder derived from oil palm, Comparative Example 1)
[Production method and size of biomass powder obtained]
300g of mesocarp fiber (fiber residue after oil is squeezed from oil palm mesocarp) is put into a superheated steam treatment device manufactured by Naomoto Kogyo Co., Ltd. with the following specifications, and atmospheric pressure superheated steam under the conditions shown in Table 1 below Processed. The treated mesocarp fiber was taken out and pulverized at 7000 rpm using the following pulverizer. The pulverization time was the time when the pulverization of the input sample was completed, and was about 10 minutes in Example 1 and about 5 minutes in Example 2.
The crushed sample was measured for particle size distribution (size distribution) by microscopic observation. Further, the water content was confirmed by a moisture measuring device. The results are also shown in Table 1. As Comparative Example 1, a pulverization test was attempted using the same apparatus for mesocarp fiber powder (biomass powder) that was not subjected to atmospheric pressure superheated steam treatment.
Specifications of thermal steam processing equipment:
Steam generating part: Heater capacity 6.3 kW
Equivalent evaporation 9.45 kg / h
Maximum working pressure 0.11 MPa
Treatment tank: Heater capacity 8 kW
Inside dimensions W 590 x D 385
x H 555 mm
Crusher specifications: Nara Machinery Seisakusho M-2 type moisture analyzer specifications: Shimadzu moisture meter (MOC-120H)

 

From the results of Table 1, it can be seen that the mesocarp fibers of Examples 1 and 2 are easily pulverized by subjecting the mesocarp fibers to superheated steam treatment. Further, it was found that the pulverization time was shorter in Example 2 having a higher steam treatment temperature than in Example 1 having a lower steam treatment temperature. From the results in Table 1, the size of the mesocarp fiber powder measured by microscopic observation in Example 1 tends to be smaller than that in Example 2, which is a result of pulverization time being twice as long. In all cases, the major axis of the particles was 100% within 1 to 500 μm. In addition, the moisture content was 5 to 7%, and it was possible to produce a composite molded body described below without any drying process. On the other hand, with respect to the mesocarp fiber powder of Comparative Example 1 that was not subjected to atmospheric pressure superheated steam treatment, the strength of the mesocarp fiber was so large that it was impossible to pulverize all even if pulverization was continued for 20 minutes.
FIG. 1 shows an optical micrograph of the crushed mesocarp fiber powder of Example 2. It can be seen that short fibers of various lengths are widely distributed. In addition, FIG. 2 shows a long diameter size distribution diagram of the mesocarp fiber powder obtained in Example 2, as an example of a histogram in which the long diameter size range is divided more finely than that in Table 1.

[Analysis of thermogravimetric changes with a thermogravimetric analyzer]
In order to confirm the composition change of the mesocarp fiber powder subjected to the atmospheric pressure superheated steam treatment, a biomass powder sample was taken in an aluminum pan, and 10 ° C under a nitrogen stream of 50 mL / min using a TG / DTA6200 manufactured by Seiko Instruments Inc. Thermogravimetric analysis was performed at a rate of temperature increase of 1 minute.
The thermogravimetric decrease curves (TG) of the samples obtained in the biomass powder production Examples 1 and 2 are shown in FIG. 3a, and their differential curves (DTG) FIG. 3b, respectively. The samples after the steam treatment in Examples 1 and 2 did not have a peak due to the decomposition of hemicellulose in the temperature range of 180 to 320 ° C., and showed a peak due to the decomposition of cellulose in the temperature range of 300 to 400 ° C. On the other hand, the untreated mesocarp fiber of Biomass powder production comparative example 1 has a thermogravimetric decrease curve (TG) (shown together in FIG. 3a) and its differential curve (DTG) (shown together in FIG. 3b) as 180 to Both a peak based on the decomposition of hemicellulose in the temperature range of 320 ° C. and a peak based on the decomposition of cellulose in the temperature range of 300 to 400 ° C. were shown.
These results indicate that the hemicellulose component in the mesocarp fiber tissue was preferentially decomposed and removed by the superheated steam treatment.

(Examples 1 to 4 for producing composite molded bodies using oil palm-derived biomass powder, Comparative Example 1)
Biomass powder production The mesocarp fiber powder produced in Examples 1 and 2 was sieved using a 100-mesh (mesh size 150 μm) sieve using a mini sieve shaker MVSI manufactured by AS ONE Corporation. The obtained mesodermal fiber powder and polypropylene (PP: Novatec PP FY-6 manufactured by Nippon Polypropylene Co., Ltd.) having a major axis of 10 to 150 μm were respectively obtained as shown in Table 2 below. And 50:50 (weight ratio), and this is a biaxial kneading extruder 160B with a vent manufactured by Imoto Seisakusho (same direction rotating twin screw, screw diameter: 20 mm, L / D: 25, number of vents: 1) Was melt-kneaded to produce a strand-shaped composite molded body. The melt-kneading conditions for compounding with polypropylene were as follows: hopper lower temperature 65 ° C., barrel temperature 190 ° C., die temperature 190 ° C., screw rotation speed 14 rpm. As Comparative Example 1, a molded body was similarly produced using polypropylene alone.
In any of composite molded body production examples 1 to 4 and comparative example 1, the melt-kneaded product of mesocarp fiber powder and polypropylene charged from the hopper was extruded as a strand from the die in about 3 minutes. The molding condition was good and no clogging occurred.

The obtained strand-like composite molded body was pelletized, and a test piece for bending test was produced at 210 ° C. using an IMC-18D1 type simple injection molding machine manufactured by Imoto Seisakusho. The size of the produced test piece is 30 mm in length, 5.1 mm in width, and 2.1 mm in thickness. The bending test was performed at a head speed of 10 mm / min according to JIS K 7171. From the obtained results, the bending strength and the flexural modulus were obtained and listed in Table 2.

 

From the results in Table 2, it was revealed that the flexural strength and flexural modulus of the composite molded body containing mesodermal fiber powder as the oil palm-derived biomass powder were higher than those of polypropylene alone.

(Example 3 for producing biomass powder derived from oil palm, Comparative Example 2)
[Production method and size of biomass powder obtained]
Table 3 below shows 50 g of foliage fiber (fiber residue after squeezing sugar components from oil palm foliage) using a superheated steam treatment apparatus in the same manner as the mesocarp fiber of biomass powder production Example 1. Under normal conditions, atmospheric pressure superheated steam treatment was performed. The treated foliage fiber was taken out and finely pulverized at 7000 rpm using a pulverizer manufactured by Nara Machinery Co., Ltd. The pulverization time was the time when the pulverization of the input sample was completed, and was about 7 minutes in the biomass powder production example 3. The crushed sample was confirmed for particle size distribution by microscopic observation and water content by a moisture measuring device. The results are also shown in Table 3. In FIG. 4, the optical microscope photograph of the foliage fiber powder produced in biomass powder production Example 3 is shown. In addition, as a biomass powder production comparative example 2, a pulverization test was attempted using the same apparatus and conditions for the foliage fibers that were not subjected to atmospheric pressure superheated steam treatment.

 

From the results of Table 3, the foliage fiber of biomass powder production example 3 was easily pulverized by subjecting the foliage fiber to superheated steam treatment, and the particle size was 100% within 1 to 500 μm. On the other hand, for the foliage fiber of Comparative Example 2 for producing biomass powder that was not subjected to atmospheric pressure superheated steam treatment, the strength of the foliage fiber was so large that it was impossible to crush all even after crushing for 20 minutes. The biomass powder size distribution data obtained by microscopic observation in Comparative Example 2 was omitted.
FIG. 4 shows an optical micrograph of the pulverized foliage fiber powder of Example 3. It can be seen that short fibers of various lengths are widely distributed. FIG. 5 shows a histogram of the major axis size distribution of the foliage fiber powder obtained in Example 3.

[Analysis of thermogravimetric changes with a thermogravimetric analyzer]
In order to confirm the composition change in the foliage fiber subjected to the atmospheric pressure superheated steam treatment, the foliage fiber sample is taken in an aluminum pan, using a TG / DTA6200 manufactured by Seiko Instruments Inc. under a nitrogen stream of 50 mL / min at 10 ° C. / Thermogravimetric analysis was conducted at a rate of temperature increase of minutes.
The thermogravimetric decrease curve (TG) of the sample obtained in biomass powder production Example 3 is shown in FIG. 6a, and its differential curve (DTG) FIG. 6b, respectively. The sample after the steam treatment of Example 2 did not have a decomposition peak in the temperature range of 180 to 320 ° C., and showed a peak based on the decomposition of cellulose in the temperature range of 300 to 400 ° C. On the other hand, the untreated foliage fibers of Biomass Powder Production Comparative Example 2 have a thermogravimetric decrease curve (TG) (shown together in FIG. 6a) and its differential curve (DTG) (shown together in FIG. 6b). Both a peak based on the decomposition of the low temperature decomposable lignin component and the hemicellulose component and a peak based on the decomposition of cellulose in the temperature range of 300 to 400 ° C were shown in the temperature range of ° C. These results indicate that the hemicellulose component and the low-temperature degradable lignin component in the foliage fiber tissue were preferentially decomposed and removed by the superheated steam treatment.

(Examples 5 and 6 for producing composite molded bodies using oil palm-derived biomass powder, Comparative Example 2)
The stalk and leaf fiber powder produced in biomass powder production Example 3 was sieved using a 100-mesh (mesh size 150 μm) sieve using a mini sieve shaker MVSI manufactured by AS ONE Corporation. As shown in Table 4, the obtained foliage fiber powder having a major axis of 10 to 150 μm and polypropylene (Novatech PP FY-6 manufactured by Nippon Polypropylene Co., Ltd.) were respectively obtained as foliage fiber powder: polypropylene = 20: 80 and 50:50 ( (By weight ratio), and this is melt-kneaded using a vented twin-screw kneading extruder 160B type (same direction rotating twin screw, screw diameter: 20 mm, L / D: 25, vent number: 1) Thus, a strand-shaped composite molded body was produced. The melt-kneading conditions for compounding with polypropylene were as follows: hopper lower temperature 65 ° C., barrel temperature 190 ° C., die temperature 190 ° C., screw rotation speed 14 rpm. As Comparative Example 2, a molded article was similarly produced using polypropylene alone. In any of composite molded body production examples 3 and 4 and comparative example 2, the melt-kneaded material of the foliage fiber powder and polypropylene charged from the hopper was extruded as a strand from the die in about 3 minutes. The molding condition was good and no clogging occurred.

The obtained strand-shaped composite molded body was pelletized, and a test piece for a bending test was created at 210 ° C. using an IMC-18D1 type simple injection molding machine manufactured by Imoto Seisakusho. The size of the prepared test piece is 30 mm long, 5.1 mm wide, and 2.1 mm thick. The bending test was performed at a head speed of 10 mm / min according to JIS K 7171. From the obtained results, the bending strength and the flexural modulus were obtained and listed in Table 4.

 

From the results of Table 4, it became clear that the flexural strength and flexural modulus of the composite molded body containing the foliage powder as the oil-derived biomass were higher than those of polypropylene alone.

Claims (8)

1. In the differential curve of thermogravimetry, there is no peak in the temperature range of 180-320 ° C, it has a peak in the temperature range of 300-400 ° C, and 50 mass% or more is derived from oil palm with a major axis in the range of 1-500 μm Biomass powder.
2. 2. The biomass powder according to claim 1, wherein the raw material is a fibrous residue after squeezing oil from the mesocarp of oil palm.
3. 2. The biomass powder according to claim 1, wherein the raw material is a fibrous residue after squeezing the sugar component from oil palm stalks and leaves.
4. 2. The biomass powder according to claim 1, wherein the raw material is an empty bunch after removing the berries from the oil palm fruit.
5. The method for producing biomass powder according to any one of claims 1 to 4, wherein the raw material is pulverized after being treated with steam at 170 to 250 ° C for 10 minutes to 6 hours.
6. A biomass formed by molding a composition containing the biomass powder according to any one of claims 1 to 4 and a prepolymer of a thermoplastic resin or a thermosetting resin in a mass ratio of 5:95 to 80:20. Composite molded body.
7. 7. The method for producing a biomass composite molded body according to claim 6, wherein the molded body is melt-molded.
8. 8. The method for producing a biomass composite molded article according to claim 7, wherein the molding is performed by an injection molding method or an extrusion molding method.

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