JP7817617B2 - Method for regenerating organic solvent, method for producing chemical treatment agent composition, and method for producing modified wood material - Google Patents

Description

The present invention relates to a chemical treatment agent composition for modifying wood materials, a method for producing modified wood materials using the same, a method for regenerating organic solvents, and a method for producing a chemical treatment agent composition.

Methylene chloride has traditionally been used as an organic solvent in chemical treatment agents for modifying wood materials, such as preservatives, insect repellents, mildew inhibitors, and flame retardants. This is due to the good solubility of active ingredients in methylene chloride, the fact that methylene chloride is not classified as a hazardous material under Japan's Fire Service Act, and its low unit price.

In recent years, legal restrictions such as the Air Pollution Control Act and the Industrial Safety and Health Act have made it difficult for the modified wood industry to use chlorinated solvents. For this reason, attempts have been made to use expensive fluorinated solvents as organic solvents in place of methylene chloride while recycling them. For example, Patent Document 1 describes a chemical treatment agent composition for modifying wood materials that contains a modifying active ingredient, an organic solvent that dissolves the active ingredient, and an organic salt compound, and has a water content of 5% by mass or less. It also describes the use of fluorocarbon solvents such as CFC-11 and HCFC-225, as well as alternative fluorocarbon solvents such as hydrofluorocarbons (HFCs) and hydrofluoroethers (HFEs), in addition to methylene chloride.

However, among fluorinated solvents, HFCs, HFEs, and other fluorocarbon alternatives have a high global warming potential (GWP), raising concerns about their impact on the global environment.

Patent No. 4723408

One of the objects of the present invention is to provide a chemical treatment agent composition for modifying wood materials that has minimal impact on the global environment. Another object is to provide a method for manufacturing modified wood materials using the chemical treatment agent composition. Another object is to provide a method for regenerating organic solvents used in chemical treatment agent compositions. Another object is to provide a method for manufacturing chemical treatment agent compositions.

According to one embodiment of the present invention, a chemical treatment agent composition is provided, which comprises an active ingredient for modifying wood materials and an organic solvent containing hydrofluoroolefins that dissolves the active ingredient.

The hydrofluoroolefins may be hydrofluoroolefins having 3 to 5 carbon atoms or hydrochlorofluoroolefins having 3 to 5 carbon atoms.

The hydrofluoroolefin may be at least one selected from 1-chloro-3,3,3-trifluoropropene, 1,2-dichloro-3,3,3-trifluoropropene, 1,1-dichloro-3,3,3-trifluoropropene, and 1-chloro-2,3,3-trifluoro-1-propene.

The chemical treatment agent composition may further contain an organic solvent other than hydrofluoroolefins.

The organic solvent other than hydrofluoroolefins may be methylene chloride.

According to one embodiment of the present invention, there is provided a method for producing modified wood material, which includes applying, impregnating, or injecting any of the above chemical treatment compositions onto a wood material, and volatilizing the organic solvent in the wood material.

According to one embodiment of the present invention, there is provided a method for regenerating an organic solvent, which includes applying, impregnating, or injecting any of the above chemical treatment agent compositions onto a wood material, volatilizing the organic solvent in the wood material, and recovering the volatilized organic solvent.

This method may further include adjusting the composition ratio of hydrofluoroolefins to organic solvents other than hydrofluoroolefins in the recovered organic solvent.

According to one embodiment of the present invention, there is provided a method for producing a chemical treatment agent composition, which includes adding an active ingredient to an organic solvent regenerated by a method for regenerating an organic solvent.

One embodiment of the present invention provides a chemical treatment agent composition for modifying wood materials that has minimal impact on the global environment. Another embodiment of the present invention provides a method for producing modified wood materials using the chemical treatment agent composition. Another embodiment of the present invention provides a method for regenerating organic solvents used in the chemical treatment agent composition. Another embodiment of the present invention provides a method for producing a chemical treatment agent composition.

FIG. 1 is a flow chart illustrating a method for producing modified wood material. FIG. 1 is a flow diagram illustrating a method for regenerating an organic solvent. FIG. 1 is a flow diagram illustrating a method for producing a chemical treatment agent composition.

The chemical treatment agent composition of the present invention, the method for producing modified wood materials using the same, the method for regenerating organic solvents, and the method for producing chemical treatment agent compositions are described in detail below. However, the chemical treatment agent composition of the present invention, the method for producing modified wood materials using the same, the method for regenerating organic solvents, and the method for producing chemical treatment agent compositions should not be interpreted as being limited to the description of the embodiments and examples shown below.

After extensive research, the inventors have found that even when hydrofluoroolefins (HFOs), particularly hydrochlorofluoroolefins (HCFOs), which have a low GWP and minimal impact on the global environment, are used as organic solvents for chemical treatment agents to modify wood materials, they are able to dissolve the chemical treatment agents and act as carriers for incorporating the chemical treatment agents into the wood materials.

In one embodiment, the chemical treatment agent composition contains an active ingredient that modifies wood materials and an organic solvent containing hydrofluoroolefins that dissolves the active ingredient. Examples of active ingredients that modify wood materials include compounds that function as preservatives, insect repellents, fungicides, antioxidants, dimensional stabilizers, antibacterial agents, anti-termite agents, or flame retardants.

Specifically, the active ingredients include anionic surfactants such as sodium alkylbenzene sulfonate, polyoxyethylene sulfate sodium salt, dialkyl succinate sulfonate sodium salt, and polyoxyethylene polycyclic phenyl ether sulfate salt; cationic surfactants such as alkyl ammonium halides (e.g., didecyl dimethyl ammonium chloride, trioctyl methyl ammonium chloride), and dihydrogenated beef tallow alkyl ethyl methyl ammonium ethosulfate; alkyl ammonium halides (e.g., tetrabutyl ammonium iodide, tetrabutyl ammonium bromide, tetrabutyl ammonium chloride, hexadecyl trimethyl ammonium bromide), and alkyl ammonium Examples of suitable ammonium salts include, but are not limited to, quaternary ammonium salt compounds such as ammonium phosphates (e.g., tetrabutylammonium hexafluorophosphate, didecyldimethylammonium hexafluorophosphate), alkylammonium borates (e.g., tetrabutylammonium tetrafluoroborate), alkylammonium sulfonates (e.g., tetraethylammonium p-toluenesulfonate, tetraethylammonium trifluoromethanesulfonate), and polyoxyethylene sulfate ammonium salts (e.g., polyoxyethylene sulfate tetrabutylammonium salts); and organometallic compounds such as aluminum alkoxides and aluminum chelates.

The hydrofluoroolefins can be one or more hydrofluoroolefins that function as organic solvents to dissolve the active ingredients. Furthermore, since the hydrofluoroolefins are removed by volatilization after the active ingredients have been impregnated into the wood material, hydrofluoroolefins that evaporate from the wood material at temperatures between 20°C and 100°C, preferably between 20°C and 80°C, and particularly preferably between 30°C and 80°C, are preferred.

In one embodiment, the hydrofluoroolefin is at least one hydrofluoroolefin selected from hydrofluoroolefins having 3 to 5 carbon atoms or hydrochlorofluoroolefins having 3 to 5 carbon atoms. Specifically, the hydrofluoroolefin is at least one hydrofluoroolefin selected from 1-chloro-3,3,3-trifluoropropene, 1,2-dichloro-3,3,3-trifluoropropene, 1,1-dichloro-3,3,3-trifluoropropene, and 1-chloro-2,3,3-trifluoro-1-propene, but is not limited to these. In one embodiment, the hydrofluoroolefin may be at least one hydrofluoroolefin selected from hydrofluoroolefins having 3 to 6 carbon atoms or hydrochlorofluoroolefins having 3 to 6 carbon atoms, preferably at least one selected from hydrofluoroolefins having 3 to 5 carbon atoms or hydrochlorofluoroolefins having 3 to 5 carbon atoms, and particularly preferably at least one selected from hydrofluoroolefins having 3 carbon atoms or hydrochlorofluoroolefins having 3 carbon atoms.

1-chloro-3,3,3-trifluoropropene (HFO-1233zd) has a boiling point of 19°C as trans-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(E)), and a boiling point of 39°C as cis-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(Z)). 1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd) has a boiling point of 60°C as trans-1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd(E)). Furthermore, the boiling point of 53°C as cis-1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd(Z)). The boiling point of 1,1-dichloro-3,3,3-trifluoropropene (HCFO-1223za) is about 54°C. 1-Chloro-2,3,3-trifluoro-1-propene (HCFO-1233yd) is a derivative of trans-1-chloro-2,3,3-trifluoro-1-propene (HCFO-1233yd(E)), which has a boiling point of 48°C. Also, cis-1-chloro-2,3,3-trifluoro-1-propene (HCFO-
The boiling point of 1233 yd(Z) is 54° C. These hydrofluoroolefins have a very low GWP (less than 10) and have a small environmental impact.

In one embodiment, the hydrofluoroolefins are Opteon (registered trademark) SF01, Opteon (registered trademark) SF05, Opteon (registered trademark) SF10, Opteon (registered trademark) SF33, Opteon (registered trademark) SF79, and DR CFX70 (manufactured by Mitsui-Chemours Fluoroproducts Co., Ltd.). The boiling point of Opteon (registered trademark) SF01 is 32°C, the boiling point of Opteon (registered trademark) SF05 is 39°C, the boiling point of Opteon (registered trademark) SF10 is 110°C, the boiling point of Opteon (registered trademark) SF33 is 33°C, the boiling point of Opteon (registered trademark) SF79 is 48°C, and the boiling point of DR CFX70 is 71°C. These hydrofluoroolefins have very low GWP and are environmentally friendly.

In one embodiment, the chemical treatment agent composition may further contain an organic solvent other than hydrofluoroolefins. The organic solvent other than hydrofluoroolefins can be selected from one or more known organic solvents used in chemical treatment agent compositions for modifying wood materials. Examples include, but are not limited to, aliphatic hydrocarbons such as n-hexane, n-heptane, and kerosene; aromatic hydrocarbons such as benzene, toluene, and xylene; chlorinated hydrocarbons such as methylene chloride and trichloroethylene; fluorocarbon solvents such as CFC-11 and HCFC-225; alternative fluorocarbon solvents such as HFCs and HFEs; nitrohydrocarbons such as nitromethane and nitroethane; nitriles such as acetonitrile; ketones such as acetone and methyl ethyl ketone; esters such as methyl formate and ethyl formate; glycol ether derivatives such as tetrahydrofuran, propylene glycol monopropyl ether, and dipropylene glycol monomethyl ether acetate; and nitrogen-containing cyclic compounds such as n-methylpyrrolidone and 1,3-dimethyl-2-imidazolidinone. In one embodiment, the chemical treatment agent composition may contain methylene chloride as an organic solvent other than hydrofluoroolefins. From the perspective of reducing impact on the global environment, it is preferable that the amount of organic solvents other than hydrofluoroolefins is significantly less than the amount of hydrofluoroolefins contained in the chemical treatment agent composition. For example, relative to 100% by weight of the organic solvents contained in the chemical treatment agent composition, the content of organic solvents other than hydrofluoroolefins is 50% by weight or less, and preferably 20% by weight or less.

In one embodiment, the active ingredient is contained in an amount of 0.01% to 5% by weight, and preferably 0.1% to 2% by weight, based on 100% by weight of hydrofluoroolefins. By adjusting the content of the active ingredient within this range, good penetration of the active ingredient into wood is achieved, the chemical treatment agent composition is sufficiently effective, and the recovery of hydrofluoroolefins, which are organic solvents, is promoted.

In one embodiment, it is preferable that the chemical treatment agent composition contains substantially no water. When a water-containing chemical treatment agent composition is injected into a wood material, the moisture content of the wood material increases significantly, causing dimensional changes in the wood material. For this reason, if the chemical treatment agent composition contains water, it is preferable that the content be such that it does not cause dimensional changes in the wood material. For 100% by weight of the chemical treatment agent composition, the water content is 5% by weight or less, and preferably 3% by weight or less.

The chemical treatment agent composition according to one embodiment of the present invention, having the above-described configuration, can modify wood materials while reducing its impact on the global environment.

[Method for producing modified wood material]
Modified wood materials can be produced using the chemical treatment agent composition described above. Figure 1 is a flow diagram illustrating a method for producing modified wood materials. The method for producing modified wood materials includes, for example, a step of drying the wood material under reduced pressure (S101), a step of applying, impregnating, or injecting the wood material with the chemical treatment agent composition (S103), and a step of volatilizing the organic solvent in the wood material (S105).

Step S101 is a step in which the wood material is dried in a reduced pressure environment of -0.001 MPaG to -0.101 MPaG in gauge pressure, which is the pressure relative to atmospheric pressure. Step S101 reduces the moisture content of the wood material, making it easier for the chemical treatment composition to penetrate, and suppressing dimensional fluctuations in the wood material after production due to moisture content in the wood material. The wood material can be dried at a temperature of 10°C to 50°C, preferably 10°C to 40°C. Note that if sufficiently dried wood is used, Step S101 is an optional step.

Step S103 is a step of contacting the wood material with the chemical treatment composition, and is carried out by coating, impregnation, or injection. The wood material can be contacted with the chemical treatment composition at atmospheric pressure. The temperature at which the chemical treatment composition is contacted with the wood material is 10°C to 100°C, preferably 20°C to 50°C. In one embodiment, the chemical treatment composition is preferably contacted with the wood material under pressure. For example, the wood material to which the chemical treatment composition has been applied may be pressurized, or the wood material may be impregnated with the chemical treatment composition under pressure. The wood material is preferably pressurized at 0.1 MPaG to 1.0 MPaG. The pressurization time is not particularly limited as long as the wood material contains the predetermined amount of chemical treatment composition, and can be set as appropriate.

Step S105 is a step in which the organic solvent in the wood material is volatilized to deposit or immobilize the active ingredient in the wood material. Step S105 is a step in which at least a portion of the organic solvent in the wood material is removed. While it is not intended to remove all of the organic solvent from the wood material, it is preferable that all of the organic solvent be removed. For example, it is preferable to remove 90% or more by weight of the organic solvent from the wood material, more preferably 95% or more by weight, and particularly preferably 99% or more by weight. The method for removing the organic solvent is not particularly limited, and examples include, but are not limited to, drying by heating, hot air drying, drying under reduced pressure, and drying in the air. The temperature for removing the organic solvent is 20°C to 100°C, preferably 30°C to 80°C. The time for removing the organic solvent is not particularly limited as long as the desired amount of organic solvent is removed from the wood material, and can be set appropriately.

By using the chemical treatment agent composition of the present invention, modified wood materials can be produced with reduced impact on the global environment.

[Method for regenerating organic solvents]
In the above-described method for producing a modified wood material, the organic solvent removed from the wood material contains hydrofluoroolefins, and is therefore preferably recovered and reused. Fig. 2 is a flow diagram illustrating a method for regenerating an organic solvent. The method for regenerating an organic solvent includes, for example, a step of recovering the evaporated organic solvent (S201), a step of filtering the recovered organic solvent (S203), a step of purifying the filtered organic solvent (S205), and a step of adjusting the composition of the purified organic solvent (S207).

Step S201 is a step of recovering the evaporated organic solvent, which involves recovering a gas containing the organic solvent, or condensing the gas containing the organic solvent and recovering the liquefied organic solvent. For example, in step S201, the gas containing the organic solvent may be stored in a tank, or the gas containing the organic solvent may be supplied to the purification step without being stored. Alternatively, the gas containing the organic solvent may be liquefied in a condenser and stored in a tank, and the liquefied organic solvent may be supplied to the purification step. By liquefying and recovering the organic solvent, it can be transported to a regeneration facility outside the modified wood material production plant, thereby reducing transportation costs.

Step S203 is a step in which the recovered organic solvent is filtered to remove solid components such as dirt and dust contained in the organic solvent. For example, the organic solvent can be filtered using a mesh or filter. Note that step S203 is an optional step and does not need to be performed if it does not interfere with supplying the organic solvent to the purification step.

Step S205 is a process for removing components and moisture derived from the wood material that have become mixed into the organic solvent during the production of the modified wood material, and includes, for example, a distillation process and a dehydration process. Therefore, it is not necessary to completely separate the hydrofluoroolefins contained in the organic solvent from the organic solvent other than hydrofluoroolefins. Furthermore, even when the organic solvent contains two or more types of hydrofluoroolefins or two or more types of organic solvents other than hydrofluoroolefins, it is not necessary to isolate each component. If necessary, the components contained in the organic solvent may be isolated and recovered. Furthermore, the purified organic solvent may be brought into contact with a porous material such as zeolite or activated carbon for dehydration.

Step S207 is a step of adjusting the composition of the organic solvent in order to reuse it. For example, missing components may be added so that the purified organic solvent has a predetermined composition ratio, or the components of the isolated and recovered organic solvent may be blended to achieve the predetermined composition ratio. Note that step S207 is an optional step and is not performed when the organic solvent consists of one type of hydrofluoroolefin. Furthermore, the recycled organic solvent may have the same or a different composition as the organic solvent contained in the chemical treatment agent composition used to produce the modified wood material. An organic solvent recycled with a different composition may be used as a solvent for a different chemical treatment agent composition.

By using the organic solvent recycling method of the present invention, it is possible to reduce the impact on the global environment and continue to produce modified wood materials.

[Method of manufacturing chemical treatment agent composition]
A chemical treatment agent composition can be produced using the recycled organic solvent. Figure 3 is a flow diagram illustrating a method for producing a chemical treatment agent composition. The method for producing a chemical treatment agent composition includes a step (S301) of adding an active ingredient to the recycled organic solvent. The produced chemical treatment agent composition may have the same composition as the chemical treatment agent composition used in the method for producing the modified wood material described above, or a different chemical treatment agent composition may be produced by adding a different active ingredient.

By using the organic solvent recycling method of the present invention, it is possible to reduce the impact on the global environment and continue to produce modified wood materials.

Specific examples of the chemical treatment agent composition for modifying wood materials according to the present invention and examples of producing modified wood materials will be presented and explained in detail below.

[Example]
<Preparation of Chemical Treatment Agent Composition>
The chemical treatment agent compositions of the examples were prepared by mixing and dissolving the active ingredients in the organic solvents listed in Table 1. The active ingredients were dissolved in the organic solvent to form a uniform solution, which was marked as "Good." TBAB stands for tetrabutylammonium bromide. HCFO-2
546mzxzz represents 3-chloro-1,1,1,6,6,6-hexafluoro-2,4-hexadiene.

<Production of modified wood materials>
50 g of the chemical treatment agent composition prepared above was placed in a glass sample bottle (50 cc, outer diameter 40 mm). 0.8 g of cedar wood pieces, 5 mm thick, were placed in a pressure-resistant sealed container and dried under reduced pressure at 1 kPa for 4 hours. After releasing the wood pieces to atmospheric pressure, they were immersed in the chemical treatment agent composition at 25°C for 1 hour. After immersion, the wood pieces were removed from the chemical treatment agent composition and allowed to dry at 25°C and atmospheric pressure, and the weight change (%) of the wood pieces over time was measured. After 64 hours of standing, the wood pieces were placed in a pressure-resistant sealed container and dried under reduced pressure at 1 kPa for 2 hours to prepare modified wood materials of the examples. The weight change of the modified wood materials of each example is shown in Table 2.

[Reference example]
Modified wood materials were prepared in the same manner as in the Examples, except that only organic solvents were used instead of the wood treatment solutions prepared in the Examples. In preparing the modified wood materials, the weight change (%) of the wood pieces over time was measured based on the weight of the wood pieces before immersion. After 40 hours of standing, the wood pieces were placed in a pressure-resistant sealed container and dried under reduced pressure at 1 kPa for 2 hours. The weight changes in the modified wood materials of each Reference Example are shown in Table 3.

The results of the Examples and Reference Examples revealed that the organic solvent volatilized from the wood pieces, while the active ingredients remained inside the wood pieces. Furthermore, when HCFO-1233yd, HCFO-1233zd, or HCFO-1223xd was used as the organic solvent, it volatilized in a shorter time than HCFO-2546mzxzz. Furthermore, in both the Examples and Reference Examples, there was no change in the dimensions of the wood pieces after drying, and no discoloration occurred.

Claims (12)

A chemical treatment agent composition containing an active ingredient for modifying wood materials and an organic solvent containing hydrofluoroolefins that dissolves the active ingredient is applied to, impregnated into, or injected into the wood materials;
volatilizing the organic solvent in the wood material;
recovering the evaporated organic solvent;
adjusting the composition ratio of the hydrofluoroolefins to the organic solvent other than hydrofluoroolefins in the recovered organic solvent;
Including,
The method for regenerating an organic solvent, wherein the active ingredient for modifying the wood material is selected from an anionic surfactant, a cationic surfactant, a quaternary ammonium salt compound, and an organometallic compound . The active ingredient that modifies the wood material is
an anionic surfactant selected from sodium alkylbenzenesulfonate, polyoxyethylene sulfate sodium salt, dialkylsuccinate sulfonate sodium salt, and polyoxyethylene polycyclic phenyl ether sulfate salt;
cationic surfactants selected from didecyldimethylammonium chloride, trioctylmethylammonium chloride, and dihydrogenated tallow alkylethylmethylammonium ethosulfate;
2. The method for regenerating an organic solvent according to claim 1, wherein the organic solvent is selected from the group consisting of a quaternary ammonium salt compound selected from alkylammonium halides, alkylammonium phosphates, alkylammonium borates, alkylammonium sulfonates, and polyoxyethylene sulfate ester ammonium salts; and an organometallic compound selected from aluminum alkoxides and aluminum chelates . The method for regenerating an organic solvent according to claim 1, wherein the hydrofluoroolefin is a hydrofluoroolefin having 3 to 5 carbon atoms or a hydrochlorofluoroolefin having 3 to 5 carbon atoms. The method for regenerating an organic solvent according to claim 1, wherein the hydrofluoroolefin is at least one selected from 1-chloro-3,3,3-trifluoropropene, 1,2-dichloro-3,3,3-trifluoropropene, 1,1-dichloro-3,3,3-trifluoropropene, and 1-chloro-2,3,3-trifluoro-1-propene. The method for regenerating an organic solvent according to claim 1, further comprising an organic solvent other than hydrofluoroolefins. 6. The method for regenerating an organic solvent according to claim 5 , wherein the organic solvent other than hydrofluoroolefins is methylene chloride. The method for regenerating an organic solvent according to claim 1, wherein the water content is 5% by weight or less based on 100% by weight of the chemical treatment agent composition. The method for regenerating an organic solvent according to claim 1, further comprising volatilizing at least 90% by weight of the organic solvent in the wood material. The method for regenerating an organic solvent according to claim 1, further comprising a step of filtering the recovered organic solvent. The method for regenerating an organic solvent according to claim 1, further comprising a step of purifying the recovered organic solvent. adding the active ingredient to the organic solvent regenerated by the method for regenerating an organic solvent according to any one of claims 1 to 10 ;
A method for producing a chemical treatment agent composition, comprising: applying, impregnating, or injecting a wood material with a chemical treatment agent composition produced by the method for producing a chemical treatment agent composition according to claim 11 ; and volatilizing the organic solvent in the wood material.
A method for producing a modified wood material, comprising: