JP4021370B2 - Polyurethane decomposition method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a polyurethane decomposing method and a polyurethane decomposing agent applied when decomposing a polyurethane contained in various industrial products, etc., and a polyurethane-containing waste treatment applied when decomposing a polyurethane-containing waste. The present invention relates to a method and a polyurethane-containing waste treatment agent.
[0002]
[Prior art]
  Polyurethane is a general term for polymer substances having a urethane bond (—NHCOO—) in the main chain, and is synthesized by addition polymerization of a polyol and a polyisocyanate. Polyurethanes are roughly classified into ester-type polyurethanes and ether-type polyurethanes depending on the type of polyol.
[0003]
  Polyurethanes are widely used in industrial products such as seats for automobiles, clothing fibers, shoe cushions, adhesives and paints. The manufacturing process of industrial products containing polyurethane, or the industrial products themselves that are no longer necessary, must undergo some kind of treatment as polyurethane-containing waste. For example, polyurethane-containing waste is reduced in volume by incineration, chemical decomposition, biodegradation, or the like, and finally discarded. In particular, biodegradation treatment is attracting attention as a method for solving air pollution, which is a problem when performing incineration, and high-cost problems, which are problematic when performing chemical decomposition.
[0004]
  In general, the biodegradation treatment of polyurethane is performed using a predetermined bacterium for ester polyurethane because ester polyurethane can be easily decomposed compared to ether polyurethane. For example, Patent Literature 1 and Patent Literature 2 disclose a technique (microorganism, enzyme) in which an enzyme (esterase) produced by bacteria cleaves and degrades an ester bond of an ester-type polyurethane. Patent Document 3 discloses a method using an enzyme containing laccase as a simple method for measuring biodegradability of plastics.
[0005]
  The ether type polyurethane is known to be hardly decomposable because the molecule has bonds that do not exist in nature such as ether bonds and urethane bonds. The present situation is not particularly known as an effective method for biodegrading ether type polyurethane.
[0006]
[Patent Document 1]
            Japanese Unexamined Patent Publication No. 9-201192
[Patent Document 2]
            JP-A-9-224664
[Patent Document 3]
            JP 2002-58500 A
[0007]
[Problems to be solved by the invention]
  Then, in view of the actual situation as described above, an object of the present invention is to provide a polyurethane decomposing method and decomposing agent that can efficiently decompose polyurethane, and a polyurethane-containing waste processing method and treating agent.
[0008]
[Means for Solving the Problems]
  In order to achieve the above-mentioned object, the present inventor has intensively studied and as a result, the mediatorWith unsaturated fatty acidsIt has been found that the polyurethane by the enzyme is decomposed in the presence of water, and further that the decomposition proceeds efficiently by adding a fatty acid, and the present invention has been completed.
[0009]
  That is, the present invention includes the following.
  (1) with enzyme, 1- Hydroxybenzotriazole, violin, 2,2 ' - Azino - Screw (3- Ethylbenzothiazoline -6- Sulfonic acid ) Diammonium, 1- Nitroso -2- Naphthol -3,6- Sodium disulfonate and Four- At least one selected from the group consisting of hydroxybenzoic acidMediatorWith unsaturated fatty acidsA method for decomposing polyurethane, comprising decomposing polyurethane in the presence of
  (2) with enzyme, 1- Hydroxybenzotriazole, violin, 2,2 ' - Azino - Screw (3- Ethylbenzothiazoline -6- Sulfonic acid ) Diammonium, 1- Nitroso -2- Naphthol -3,6- Sodium disulfonate and Four- At least one selected from the group consisting of hydroxybenzoic acidWith mediatorWith unsaturated fatty acidsPolyurethane decomposing agent based on
[0010]
  Here, for example, laccase can be used as the enzyme. That is, polyurethane can be decomposed in the presence of laccase and 1-hydroxybenzotriazole. Moreover, the said method and decomposition agent show the decomposition efficiency outstanding with respect to the ether type polyurethane.
  Moreover, the degradation efficiency of polyurethane can be remarkably improved by making unsaturated fatty acid coexist in a reaction system.
[0011]
  Furthermore, the polyurethane contained in the waste can be decomposed by applying the above (1) and (2). That is, the present invention relates to an enzyme and, 1- Hydroxybenzotriazole, violin, 2,2 ' - Azino - Screw (3- Ethylbenzothiazoline -6- Sulfonic acid ) Diammonium, 1- Nitroso -2- Naphthol -3,6- Sodium disulfonate and Four- At least one selected from the group consisting of hydroxybenzoic acidMediatorWith unsaturated fatty acidsA polyurethane-containing waste treatment method characterized by decomposing polyurethane in the presence of, 1- Hydroxybenzotriazole, violin, 2,2 ' - Azino - Screw (3- Ethylbenzothiazoline -6- Sulfonic acid ) Diammonium, 1- Nitroso -2- Naphthol -3,6- Sodium disulfonate and Four- At least one selected from the group consisting of hydroxybenzoic acidWith mediatorWith unsaturated fatty acidsA polyurethane-containing waste treatment agent containing as a main component is included.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described in detail.
  The polyurethane decomposing method according to the present invention (hereinafter simply referred to as a polyurethane decomposing method) is a method of treating an object containing polyurethane in the presence of an enzyme and a mediator.
[0013]
  In the polyurethane decomposing method, laccase can be used as an enzyme. As an enzyme other than laccase, for example, manganese peroxidase, horseradish peroxidase and lipoxygenase can be used.
[0014]
  The laccase is not limited to its origin and degree of purification as long as it has a function of catalyzing the reaction of decomposing benzenediol into 1,2-benzoquinone and water. That is, in the method for decomposing polyurethane, laccase derived from various microorganisms, laccase derived from fungi, laccase derived from urushi can be used.
[0015]
  In the method for decomposing polyurethane, when laccase is used, for example, the laccase concentration is 1 to 300 U / ml, preferably 1 to 150 U / ml, more preferably 1 to 20 U / ml.
[0016]
  In the polyurethane decomposition method, 1-hydroxybenzotriazole can be used as a mediator. As a mediator other than 1-hydroxybenzotriazole, 1-hydroxybenzotriazole can be used. Examples of mediators include biolin (Violuric acid: VA) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium (ABTS). ), Sodium 1-nitroso-2-naphthol-3,6-disulfonate (sometimes abbreviated as NNDS) and 4-hydroxybenzoic acid (sometimes abbreviated as 4HBA). These mediators may be used alone or in combination.
[0017]
  In the polyurethane decomposition method, when 1-hydroxybenzotriazole is used, the concentration of 1-hydroxybenzotriazole is preferably 1 to 10 mM, and more preferably 1 to 2 mM.
[0018]
  Furthermore, in the polyurethane decomposing method, an unsaturated fatty acid can be present in addition to the enzyme and the mediator, and the object to be decomposed containing polyurethane can be treated. By treating in the presence of an unsaturated fatty acid, it is possible to delay the polyurethane decomposition start time and improve the polyurethane decomposition efficiency.
[0019]
  Examples of unsaturated fatty acids include linoleic acid, linolenic acid and oleic acid. These unsaturated fatty acids may be used alone or in combination.
[0020]
  On the other hand, in the polyurethane decomposing method, any object containing polyurethane can be used as an object. Specific examples of the object include various industrial products manufactured using polyurethane or wastes thereof, or processed products obtained by pretreating the industrial products and wastes. Industrial products include, for example, automobile sheets, clothing fibers, shoe cushions, adhesives, paints, and the like. Specific examples of the pretreatment include a process of pulverizing an object such as an industrial product with a shredder or the like, a heat treatment, a heating / humidification treatment, a light irradiation treatment, a light irradiation / humidification treatment, and the like.
[0021]
  In the polyurethane decomposing method, the polyurethane contained in the object can be decomposed by bringing the object into contact with the reaction system containing the enzyme and the mediator described above. Here, in the polyurethane decomposing method, polyurethane having any monomer component can be decomposed as polyurethane, but particularly ether type polyurethane having an ether bond in the molecule can be efficiently decomposed.
[0022]
  The reaction system can be prepared by, for example, mixing an enzyme, a mediator, and other components such as an unsaturated fatty acid in a suitable buffer solution. When the target object is brought into contact with the prepared reaction system, the target object may be simply immersed in the reaction system, or may be stirred while the target object is immersed in the reaction system.
[0023]
  At this time, the temperature of the reaction system is preferably maintained in the range of 30 to 80 ° C, preferably 30 to 50 ° C, more preferably 30 to 35 ° C. The pH of the reaction system is preferably maintained in the range of 3.0 to 6.0, preferably 4.0 to 4.5. Furthermore, the ratio of the object contained in the reaction system is preferably maintained in the range of 5 to 50 g / L, preferably 5 to 10 g / L. In addition, the reaction time is preferably 72 to 120 hours, preferably about 72 hours, for example, addition of each component or transfer to a new reaction solution.
[0024]
  According to the polyurethane decomposing method as described above, the polyurethane contained in the object can be efficiently decomposed. In particular, according to the polyurethane decomposing method, ether type polyurethane can be efficiently decomposed. Moreover, when linoleic acid is added to the reaction system, the polyurethane decomposition reaction contained in the object can be delayed and the decomposition efficiency can be improved.
[0025]
【Example】
  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, the technical scope of this invention is not limited to these Examples.
  [Experimental example1]
  First, a reaction solution having the following composition was prepared. The composition of the reaction solution is 10 mM sodium tartrate buffer (pH 4.5), 0.05% Tween 20, 1-hydroxybenzotriazole (hereinafter HBT), 1 mM HBT, and 9 mM linoleic acid when linoleic acid is added. When adding laccase, 10 U laccase was used.
[0026]
  Next, 10 ml of the reaction solution was filled in a 50 ml tube, and about 25 mg of a polyurethane sheet (5 cm × 2 cm) was added. Then, it was allowed to react by shaking for 5 days at 35 ° C. After completion of the reaction, the sheet was taken out, washed thoroughly, dried at 80 ° C. for 8 hours, and then weighed.
[0027]
  The results are shown in FIG. Note that “Lac” in FIG. 1 is the result of using a sample containing laccase in the reaction solution and not containing HBT and linoleic acid, and “Lac / HBT” contains laccase and HBT in the reaction solution and linoleic acid. The results using a sample that does not contain `` Lac / HBT / LA '' are the results using a sample containing laccase, HBT and linoleic acid in the reaction solution, and `` control '' contains laccase in the reaction solution It is the result using the sample containing HBT and linoleic acid. Moreover, the vertical axis | shaft in FIG. 1 has shown the weight decreasing rate of the polyurethane sheet.
[0028]
  As can be seen from FIG. 1, the degradation reaction does not proceed only by adding laccase, but the degradation rate was 6% when HBT was added. Further, when linoleic acid was further added, the decomposition reaction did not proceed.
[0029]
  [Experimental example2]
  Experimental example2, except that about 50mg of polyurethane test piece (1cm square) was used instead of polyurethane sheet (5cm x 2cm)Experimental exampleThe decomposition reaction was carried out in the same manner as in 1.
  The results are shown in FIG. Note that “Lac (10U) / HBT” in FIG. 2 is the result of using a sample containing laccase and HBT but not linoleic acid in the reaction solution, and “Lac (10U) / HBT / LA” is the reaction solution. This is a result of using a sample containing laccase, HBT and linoleic acid in the inside, and “control” is a result of using a sample containing HBT and linoleic acid without containing laccase in the reaction solution. Moreover, the vertical axis | shaft in FIG. 2 has shown the weight decreasing rate of the polyurethane test piece.
[0030]
  As can be seen from FIG. 2, even when a polyurethane test piece was used as an object, the decomposition reaction did not proceed only by adding laccase, and when HBT was added, the decomposition rate was 3.5%. Further, when linoleic acid was further added, the decomposition reaction did not proceed.
[0031]
  [Experimental example3]
  Experimental example3 examined the optimal concentration of laccase and the type of mediator.
  First, 10 mM sodium tartrate buffer (pH 4.5), 0.05% Tween20, 1 mM mediator to be evaluated, and when adding linoleic acid, prepare various reaction solutions by mixing 9 mM linoleic acid and laccase of the specified concentration. did. HBT, 4-hydroxybenzoic acid (hereinafter referred to as HBA), veratryl alcohol (hereinafter referred to as VA), phenol (hereinafter referred to as PHE), methionine (hereinafter referred to as MET), and cysteine (hereinafter referred to as CYC) are used as mediators to be evaluated. It was. The concentration of laccase was 0.5%, 5% or 50%.
[0032]
  Using various prepared reaction solutionsExperimental exampleThe decomposition reaction was performed in the same manner as in Example 2, and the weight change of the polyurethane test piece was measured. The result is shown in FIG. In FIG. 3, “Lac” shows the result of using a sample containing laccase in the reaction solution and not containing mediator and linoleic acid, and “Lac” is a sample containing laccase in the reaction solution and not containing mediator and linoleic acid. `` Lac / HBT '' is a result of using a sample containing laccase and HBT in the reaction solution and not containing linoleic acid, `` Lac / LA / HBT '' is a result of using laccase in the reaction solution, It is the result using the sample containing HBT and linoleic acid. Samples using HBA, VA, PHE, MET or CYC instead of HBT are `` Lac / LA / HBA '', `` Lac / LA / VA '', `` Lac / LA / PHE '', `` Lac / These are shown in FIG. 3 as “LA / MET” and “Lac / LA / CYC”. Moreover, the vertical axis | shaft in FIG. 3 has shown the weight change rate of the polyurethane test piece.
[0033]
  As can be seen from FIG. 3, when HBT was added as a mediator, a weight reduction was observed, but when HBA, VA, PHE, MET, or CYC was added as a mediator, no weight reduction was observed. On the other hand, as can be seen from FIG. 3, when HBT was added as a mediator and laccase was added at 0.5% or 5%, weight loss was 4.9% and 5.2%, respectively. In contrast, when HBT was added as a mediator and laccase was added 50%, almost no degradation was observed. Further, when linoleic acid was further added, the decomposition reaction did not proceed in any case. From the above results, it was revealed that it is preferable to treat with less than 50% laccase in the presence of HBT for the degradation of polyurethane.
[0034]
  [Example 1]
  Example 1Then, it verified that the decomposition efficiency of a polyurethane decomposition | disassembly reaction could be improved by adding linoleic acid.
  First, mix 10 mM sodium tartrate buffer (pH 4.5), 0.05% Tween20, 1 mM HBT when adding HBT, and 9 mM linoleic acid and 0.5% laccase when adding linoleic acid. A liquid was prepared.
[0035]
  Next, we prepared 36 (weighing times (12 times) x3) x3) polyurethane test pieces that weighed in advance, and put one polyurethane test piece in the reaction tube containing the prepared various reaction solutions. It put in, and it was made to react, stirring at 30 degreeC. At this time, the polyurethane test piece was taken out every 5 days, and was allowed to react with a new reaction solution while continuing to stir at 30 ° C. without washing.
[0036]
  The reaction was carried out for 36 days, and on days 1, 4, 6, 8, 11, 14, 18, 22, 26, 29, 32, and 36, three polyurethane test pieces in the reaction solution were taken out three by three and washed thoroughly. After drying at 0 ° C. for 8 hours, its weight was measured.
[0037]
  FIG. 4 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 4, “Lac” shows the result of using a sample containing laccase in the reaction solution and not containing mediator and linoleic acid, and “Lac / HBT” contains laccase and HBT in the reaction solution, and linoleic acid. "Lac / LA / HBT" is the result using a sample containing laccase, HBT and linoleic acid in the reaction solution. In FIG. 4, the vertical axis indicates the rate of change in weight.
[0038]
  As can be seen from FIG. 4, the decomposition reaction does not proceed only by adding laccase, but when HBT is added, a weight reduction was observed immediately after the start of the reaction. Specifically, when HBT was added, a 4% weight loss was observed in 4 days from the start of the reaction, and a 10% weight loss was observed up to 14 days thereafter. On the other hand, when HBT and linoleic acid were added, no weight loss was observed for 6 days from the start of the reaction, but after that, decomposition was accelerated and showed a 13% weight loss over 14 days. Furthermore, when HBT and linoleic acid were added, a significant weight reduction was observed as compared with the case where only HBT was added. Specifically, on day 36, when only HBT was added, the weight decreased by 18%, whereas when HBT and linoleic acid were added, the weight decreased by 80%.
[0039]
  From these results, it became clear that according to the reaction solution containing laccase, HBT and linoleic acid, the polyurethane decomposition reaction can be delayed and the polyurethane decomposition efficiency can be improved.
[0040]
[Example 2]
  Example 2Then, we verified that the degradation efficiency of polyurethane can be improved by adding laccase, linoleic acid, and HBT to the reaction solution.
  First, add 10 mM sodium tartrate buffer (pH 4.5), 0.05% Tween20, 1 mM HBT when adding HBT, 50 mg laccase when adding 9 mM linoleic acid and laccase when adding linoleic acid. Various reaction solutions were prepared by mixing.
[0041]
  Next, a polyurethane test piece whose weight was measured in advance was prepared, and each polyurethane test piece was put into a reaction tube containing various prepared reaction solutions, and reacted while being stirred at 30 ° C. In this example, laccase, linoleic acid, and HBT were added individually or in appropriate combinations every 5 days, and the reaction was allowed to proceed for 45 days. During this time, the polyurethane test piece in the reaction solution was taken out as appropriate, washed thoroughly and dried at 80 ° C. for 8 hours, and then its weight was measured.
[0042]
  FIG. 5 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 5, “Lac” shows the result using a sample in which laccase was added to the reaction solution, “LA” shows the result using a sample in which linoleic acid was added to the reaction solution, and “HBT”. Shows the results of using a sample with additional HBT added to the reaction solution. In FIG. 5, “Lac / HBT / LA” shows the results of using a sample with laccase, HBT and linoleic acid added to the reaction solution, and “Lac / HBT” shows the laccase and HBT added to the reaction solution. "Lac / LA" shows the result using a sample with laccase and linoleic acid added to the reaction solution, and "HBT / LA" shows HBT and linoleic acid in the reaction solution. The result using the added sample is shown. In FIG. 5, the vertical axis represents the rate of change in weight.
[0043]
  As can be seen from FIG. 5, in the samples to which linoleic acid was additionally added, the decomposition reaction proceeded well and the decomposition efficiency was improved. In particular, in the sample to which linoleic acid and HBT except laccase were added, the most significant weight loss (40% weight loss / 40 days) was observed. From this, it was revealed that by adding linoleic acid and HBT, the decomposition reaction of polyurethane can be maintained over a long period of time, and excellent polyurethane decomposition efficiency can be achieved.
[0044]
[Example 3]
  Example 3Then, we verified the aeration decomposition test using a mini jar fermenter.
  First, when adding 10 mM sodium tartrate buffer (pH 4.5), 0.05% Tween20, HBT to a 1 L jar fermenter, when adding 1 mM HBT, linoleic acid When adding 9 mM linoleic acid and laccase, various reaction solutions were prepared by mixing 5 mg / ml laccase.
[0045]
  Next, the polyurethane test piece whose weight was measured in advance was put into the reaction solution in the jar fermenter, and reacted at 30 ° C. while aeration was performed at an aeration rate of 0.5 v / v / min. At this time, laccase, linoleic acid and HBT were added every 5 days, or only linoleic acid was added every 5 days. During this time, the polyurethane test piece in the reaction solution was taken out as appropriate, washed thoroughly and dried at 80 ° C. for 8 hours, and then its weight was measured.
[0046]
  FIG. 6 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 6, “Lac / HBT / LA” shows the results using a sample with laccase, HBT and linoleic acid added to the reaction solution, and “LA” uses a sample with laccase added to the reaction solution. Shows the results. In FIG. 6, the vertical axis represents the rate of change in weight.
[0047]
  As can be seen from FIG. 6, the polyurethane decomposition reaction proceeded in the same manner both in the case where only linoleic acid was added and in the case where laccase, linoleic acid and HBT were additionally added. In particular, as shown in FIG. 5, the maximum weight loss was 35% / 14 days. this isExample 2Compared with the results, it means that the decomposition rate is increased by 2.5 times, and the effect of aeration is shown.
[0048]
[Example 4]
  Example 4Then, the continuous aeration stirring decomposition test using the mini jar fermenter was verified.
  In this example, the reaction solution in the 1 L jar fermenter was stirred at 400 rpm, and the decomposition reaction was performed, except that laccase and HBT were additionally added instead of adding linoleic acid alone.Example 3In the same manner as above, the polyurethane test piece was subjected to a decomposition reaction and its weight was measured.
[0049]
  FIG. 7 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 7, “Lac / HBT / LA” shows the results using a sample in which laccase, HBT and linoleic acid were added to the reaction solution, and “LA” used the sample in which laccase was added to the reaction solution. Shows the results. In FIG. 7, the vertical axis represents the rate of change in weight.
[0050]
  As can be seen from FIG. 7, in the sample to which laccase, HBT, and linoleic acid were additionally added, the prototype of the polyurethane test piece collapsed on the 14th day, resulting in complete decomposition. this is,Example 3This means that the decomposition rate is increased by a factor of 3 compared to the above results, and shows the effect of stirring.
[0051]
[Example 5]
  Example 5Then, various mediators were added to the reaction solution, and the reaction efficiency in the polyurethane decomposition reaction was verified.
  In this example, instead of HBT, 4-hydroxybenzoic acid (4HBA), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium (ABTS), violin (Violuric acid) : VA), except using 1-nitroso-2-naphthol-3,6-sodium disulfonate (NNDS)Example 1In the same manner as above, the polyurethane test piece was subjected to a decomposition reaction and its weight was measured.
[0052]
  FIG. 8 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 8, the type of added mediator is abbreviated. In FIG. 8, the vertical axis indicates the weight change rate.
[0053]
  As can be seen from FIG. 8, it was clarified that when any mediator was used, the polyurethane decomposition reaction proceeded when added together with linoleic acid. In HBT, the polyurethane decomposition reaction proceeds even when linoleic acid is not added alone, but the polyurethane decomposition reaction proceeds more effectively when added together with linoleic acid. In particular, when both HBT and linoleic acid were added, the weight decreased by 80% on the 36th day.
[0054]
[Example 6]
  Example 6Then, various unsaturated fatty acids were added to the reaction solution, and the reaction efficiency in the polyurethane decomposition reaction was verified.
  In this example, in addition to linoleic acid, linolenic acid, oleic acid, and arachidonic acid were used as unsaturated fatty acids, and azelaic acid and n-caproic acid were used as saturated fatty acids. These unsaturated fatty acids and saturated fatty acids were added so as to be 9 mM.
[0055]
  In this example, first, to include any of these unsaturated fatty acids and saturated fatty acids.Example 1A reaction solution was prepared in the same manner as described above. Next, polyurethane test pieces were put one by one in reaction tubes containing various reaction solutions, and reacted while being stirred at 30 ° C. At this time, laccase, HBT and unsaturated fatty acid or saturated fatty acid were additionally added on the fifth and ninth days. In addition, the polyurethane test piece was taken out over time, washed well, dried at 80 ° C. for 8 hours, and the weight was measured.
[0056]
  FIG. 9 shows the time course of the weight change rate calculated from the weight measurement results. In FIG. 9, the type of added unsaturated fatty acid and saturated fatty acid is abbreviated. In FIG. 9, the vertical axis indicates the rate of weight change.
[0057]
  As can be seen from FIG. 9, when unsaturated fatty acids, particularly linoleic acid, linolenic acid and oleic acid were added, the effect of improving the polyurethane decomposition reaction could be achieved. In particular, when oleic acid and linoleic acid were added, the weight decreased by 17% on the 26th day.
[0058]
[Example 7]
  Example 7Then, the decomposition reaction at the time of using ester type polyurethane was verified. In this example, ester type polyurethane was used and the reaction solution was changed every 3 or 4 days.Example 1The polyurethane test piece was decomposed in the same manner as described above, and its weight was measured.
[0059]
  FIG. 10 shows the time course of the weight change rate calculated from the results of the weight measurement. In FIG. 10, “Lac (50 mg)” shows the result of using a sample containing laccase in the reaction solution and no mediator and linoleic acid, and “Lac (50 mg) / HBT” shows the result of using laccase and mediator in the reaction solution The results using a sample containing no linoleic acid are shown, and “Lac (50 mg) / HBT / LA” is the result using a sample containing laccase, HBT and linoleic acid in the reaction solution. In FIG. 10, the vertical axis indicates the rate of change in weight.
[0060]
  As can be seen from FIG. 10, when only laccase is added to the ester type polyurethane, the decomposition reaction hardly proceeds, but when laccase and HBT are added and when laccase, HBT and linoleic acid are added. Was markedly degraded. In particular, when laccase, HBT, and linoleic acid were added, the ester-type polyurethane was degraded until a weight loss of 51% at 37 days.
[0061]
【The invention's effect】
  As described above in detail, according to the polyurethane decomposing method and the decomposing agent according to the present invention, polyurethane can be efficiently decomposed. Moreover, according to the polyurethane containing waste processing method and processing agent which concern on this invention, the waste containing a polyurethane can be processed efficiently.
[Brief description of the drawings]
FIG. 1 is a characteristic diagram showing a relationship between a reaction solution composition and weight loss when a decomposition reaction is performed using a polyurethane sheet.
FIG. 2 is a characteristic diagram showing the relationship between the reaction solution composition and weight loss when a decomposition reaction is performed using a polyurethane test piece.
FIG. 3 is a characteristic diagram showing the relationship between the reaction solution composition and the rate of weight change when a decomposition reaction is performed using various mediators and various concentrations of laccase.
FIG. 4 is a characteristic diagram showing the relationship between the number of reaction days and the rate of change in weight, as a result of examining the influence of linoleic acid on the decomposition efficiency.
FIG. 5 is a characteristic diagram showing the relationship between the number of reaction days and the rate of change in weight, as a result of verifying the effect of additional addition on the decomposition efficiency.
FIG. 6 is a characteristic diagram showing the relationship between the number of reaction days and the rate of weight change, as a result of examining the influence of aeration on decomposition efficiency.
FIG. 7 is a characteristic diagram showing the relationship between the number of days of reaction and the rate of change in weight, as a result of verifying the influence of stirring on the decomposition efficiency.
FIG. 8 is a characteristic diagram showing the relationship between the number of reaction days and the rate of weight change, as a result of examining the influence of the type of mediator on the decomposition efficiency.
FIG. 9 is a characteristic diagram showing the relationship between the number of reaction days and the rate of change in weight, as a result of verifying the effect of the type of unsaturated fatty acid on the decomposition efficiency.
FIG. 10 is a characteristic diagram showing the relationship between the number of reaction days and the rate of change in weight, as a result of verifying the decomposition efficiency for ester-type polyurethane.

Claims (14)

An enzyme, 1-hydroxybenzotriazole, Biorurin, 2,2 '- azino - bis (3-ethyl benzo thiazoline-6-sulfonic acid) diammonium, 1-nitroso-2-naphthol-3,6-sodium disulfonate and A method for decomposing a polyurethane, comprising decomposing a polyurethane in the presence of at least one mediator selected from the group consisting of 4 -hydroxybenzoic acid and an unsaturated fatty acid .   The method for decomposing a polyurethane according to claim 1, wherein the enzyme is laccase. The unsaturated fatty acids linoleic acid, according to claim 1 polyurethane decomposition method, wherein the at least one unsaturated fatty acid selected from the group consisting of linolenic acid and oleic acid.   2. The polyurethane decomposing method according to claim 1, wherein the polyurethane to be decomposed mainly comprises ether type polyurethane. An enzyme, 1-hydroxybenzotriazole, Biorurin, 2,2 '- azino - bis (3-ethyl benzo thiazoline-6-sulfonic acid) diammonium, 1-nitroso-2-naphthol-3,6-sodium disulfonate and A polyurethane decomposing agent mainly comprising at least one mediator selected from the group consisting of 4 -hydroxybenzoic acid and an unsaturated fatty acid . The polyurethane decomposing agent according to claim 5 , wherein the enzyme is laccase. 6. The polyurethane decomposing agent according to claim 5 , wherein the unsaturated fatty acid is at least one unsaturated fatty acid selected from the group consisting of linoleic acid, linolenic acid and oleic acid. An enzyme, 1-hydroxybenzotriazole, Biorurin, 2,2 '- azino - bis (3-ethyl benzo thiazoline-6-sulfonic acid) diammonium, 1-nitroso-2-naphthol-3,6-sodium disulfonate and A method for treating polyurethane-containing waste, comprising treating in the presence of at least one mediator selected from the group consisting of 4 -hydroxybenzoic acid and an unsaturated fatty acid . The polyurethane-containing waste treatment method according to claim 8 , wherein the enzyme is laccase. The polyurethane-containing waste treatment method according to claim 8 , wherein the unsaturated fatty acid is at least one unsaturated fatty acid selected from the group consisting of linoleic acid, linolenic acid and oleic acid. 9. The method for treating polyurethane-containing waste according to claim 8 , wherein the polyurethane-containing waste to be decomposed comprises ether type polyurethane. An enzyme, 1-hydroxybenzotriazole, Biorurin, 2,2 '- azino - bis (3-ethyl benzo thiazoline-6-sulfonic acid) diammonium, 1-nitroso-2-naphthol-3,6-sodium disulfonate and A polyurethane-containing waste treatment agent comprising at least one mediator selected from the group consisting of 4 -hydroxybenzoic acid and an unsaturated fatty acid as main components. The polyurethane-containing waste treatment agent according to claim 12 , wherein the enzyme is laccase. The polyurethane-containing waste treatment agent according to claim 12 , wherein the unsaturated fatty acid is at least one unsaturated fatty acid selected from the group consisting of linoleic acid, linolenic acid, and oleic acid.

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