KR20180002125A - Production of biopolyol derived from lignin residue through solvothermal liquefaction using butanediol and synthesis of biopolyurethane - Google Patents

Abstract

The present invention relates to a process for synthesizing a lignin-derived polyol liquefied by liquefaction reaction of lignin and a first solvent under acid catalysis; And a second step of synthesizing a polyurethane from the liquefied lignin-derived polyol through a polymerization reaction with a second solvent, and a bio-polyurethane produced thereby. In the present invention, a bio-polyurethane can be prepared from lignin and a bio-polyol using the butanediol, which is a solvent derived from a bio-solvent in the thermal liquefaction reaction of a solvent, The use of raw materials derived from petroleum resources can be reduced.

Description

Production of BioPolyol Derived from Lignin By-Products by Thermal Liquefaction of Butanediol Solvent and Synthesis of BioPolyurethanes {Production of biopolyol derived from lignin residue through solvothermal liquefaction using butanediol and synthesis of biopolyurethane}

The present invention relates to the preparation of biopolyols derived from lignin byproducts through the thermal liquefaction reaction of butanediol solvents and the synthesis of bio-polyurethanes.

There is a growing interest in biomass due to the depletion of petroleum resources and environmental problems. Research is actively under way to utilize lignocellulose, a lignocellulose product, as biomass. Empty fruit bunch lignocellulose, especially utilized as biomass, is composed of 37.3 ~ 46.5% of cellulose, 25.3 ~ 33.8% of hemicellulose and 27.6 ~ 32.5% of lignin, and the crude palm oil production process As a by-product. The EFB lignocellulose may be biologically converted to produce a biosugar. The biosugar may be used as bioethanol, biofuel or L-lactic acid. However, a large amount of EFB lignin is produced as a by-product of the biological conversion process. Lignin is mostly burned or abandoned as low-cost fuel because of its intractable nature.

Lignin contains functional groups such as a hydroxyl group, a carbonyl group, a methoxyl group and the like, and particularly contains a large amount of hydroxyl groups in the molecule. As a result, lignin can be used to replace petroleum-derived polyols. Research into the conversion of lignin, a low-cost byproduct, into a biopolyol through solvothermal liquefaction is actively underway. For example, Yanqia et al. Liquefied lignin using polyethylene glycol 400 (PEG 400) and glycerol as a solvent under sulfuric acid (H ₂ SO ₄ ) catalyst conditions.

Biopolyol can be used as a raw material for bioplastics, and lignin has become a high-value-added raw material for replacing raw materials derived from petroleum resources and producing environmentally friendly plastics. Particularly, the polyurethane can be synthesized through a polymerization reaction between the hydroxyl group of the polyol and the isocyanate group. In this connection, Li et al. Proceeded a liquefaction reaction under similar conditions of alkali lignin, and synthesized bio-polyurethane through polymerization reaction of liquefied lignin-derived polyol with methylene diisocyanate. Polyurethanes are widely used as six synthetic polymers because of their excellent physical properties. Thus, when the polyol used in the polyurethane process is replaced with a bio-polyol derived from lignin, it is possible to reduce the dependency on petroleum resources, and it is possible to manufacture an environment-friendly bio-plastic.

However, the conventional technology has a problem of using a large amount of solvent derived from petroleum resources. That is, in the conventional technology, the solvent thermal liquefaction reaction mainly uses ethylene glycol (EG), polyethylene glycol (PEG), phenol, and glycol as a reaction solvent, and uses an acid or base catalyst at a reaction temperature of 100-200 ° C, And the like. However, when the bio-polyol thus produced is used as a raw material for plastics, it is difficult to classify it as "bio-plastic" because raw materials derived from petroleum resources account for more than 70% Reference).

Accordingly, the present inventors synthesized bio-polyols using butanediol, which is a solvent that can be produced by a bioprocess in the thermal liquefaction process of a solvent for EFB lignin, kraft lignin, and red pine lignocellulose, It was confirmed that bio-polyurethane could be synthesized as a plastic, and the present invention was completed.

An object of the present invention is to provide a method for producing a bio-polyurethane having a high proportion of a bio-material, and more particularly, a method for producing a bio-polyurethane conforming to a bio-plastic standard.

It is an object of the present invention to provide a bio-polyurethane that conforms to the bio-plastic standard.

A first aspect of the present invention is a process for producing a lignin-derived biopolyol which is liquefied by liquefaction reaction of lignin and a first solvent under acid catalysis; And a second step of synthesizing a polyurethane from the liquefied lignin-derived bio-polyol through a polymerization reaction with a second solvent.

In the present invention, the lignin is selected from the group consisting of Empty Fruit Bunches lignin, Kraft lignin, lignocellulose, lignosulfonate, Organosolv lignin, steam explosion lignin, lignin or weak acid lignin, preferably EFB lignin, kraft lignin or lignocellulose.

Lignin may be a structure in which lignin units having a benzene ring structure are bonded in an irregular form as shown in Formula 1 below

[Chemical Formula 1]

The amount of lignin used in the first step is preferably 5 to 35% by weight based on the total weight of the solvent. If the amount is less than 5% by weight, the proportion of the biomass in the polyol is low. If the amount is more than 35% by weight, the biomass conversion rate may be drastically reduced due to the lack of the active solvent.

The first solvent preferably comprises 1,4-butanediol, levo-2,3-butanediol, meso-2,3-butanediol or dextro-2,3-butanediol.

Butanediol has isomers of 1,4-butanediol (1,4-BD) and 2,3-butanediol (2,3-BD) 3-BD (hereinafter referred to as 2,3-BDL), meso-2,3-BD (hereinafter referred to as 2,3-BDM), and dextro- .

In the present invention, butanediol is preferably bio-butanediol (bio-BD) produced through a biological process using recombinant Escherichia coli. In the case of 1,4-bio-BD, 2,3-bio-BDL is converted to glucose, 2,3-bio-BDM is converted to crude glycerol in glucose, xylose or sucrose, .

More preferably, the first solvent comprises levo-2,3-butanediol. In one embodiment of the present invention, the highest biomass conversion was obtained when levo-2,3-butanediol was used as a solvent.

The first solvent may contain a cosolvent in an amount of 10 to 50 wt% relative to the total weight of the first solvent to increase the liquefaction efficiency. PEG 300 (poly ethylene glycol 300, MW: 285 to 315 g / mol), PEG 400 (poly ethylene glycol 400, MW: 380 To 420 g / mol).

The acid catalyst may be a sulfuric acid catalyst, a nitric acid catalyst, or the like, but is not limited thereto.

The first step is preferably carried out at 100-170 < 0 > C. When the temperature is lower than 100 ° C, the liquefaction of lignin is not accelerated. When the temperature exceeds 170 ° C, the polymerization reaction between the active groups of the lignin decomposed occurs and the biomass conversion rate may be drastically reduced. Especially, as the reaction temperature increased from 100 ℃ to 150 ℃, the biomass conversion rate increased from 49.3% to 63.3%. This is the result of accelerated liquefaction of lignin due to temperature increase.

Since the polyol is synthesized from the liquefaction reaction of butanediol, which is a solvent derived from lignin and bio, it may be a bio-polyol.

The present invention includes a second step of synthesizing a bio-polyurethane from the liquefied lignin-derived polyol through a polymerization reaction with a second solvent.

The present invention is characterized in that bio-polyurethane is synthesized using only bio-polyols derived from 100% bio-products. Accordingly, the bio-polyurethane may have a biomass content of 25% or more, and thus can satisfy the American Bio-Plastic Standard ASTM D 6366.

The second solvent is selected from the group consisting of toluene diisocyanate (TDI), methylene diphenyl diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, xylylene diisocyanate Xylylene diisocyanate, tetramethylene diisocyanate, cyclohexylene diisocyanate, dicyclohexylmethane 4,4'-diisocyanate, poly (hexamethylene diisocyanate, Poly (propylene glycol) tolylene 2,4-diisocyanate terminated, poly (hexamethylene diisocyanate), poly (propylene glycol) tolylene 2,4-diisocyanate terminated, telechelic isocyanate-terminated polybutadiene) Can be used.

The second aspect of the present invention can provide a bio-polyurethane produced according to the first aspect of the present invention and having a biomass content of 25% or more and satisfying the ASTM D6366 standard.

According to the present invention, a high proportion of bio-derived polyol can be produced by using butane diol, which can be produced through a biological process, as a solvent for thermal liquefaction reaction of lignin, and bioplastic synthesis is possible using the same. Conventionally, lignin, which is a type of biomass, has been largely discarded because it is difficult to handle. However, in the present invention, a bio-polyol is prepared from lignin by using a butano diol, which is a bio- The bio-polyurethane can be produced. Therefore, it is possible to reduce the use of raw materials derived from petroleum resources, which is conventionally a material of polyurethane.

: 산가)
도 3은 바이오 부탄다이올 이성질체에 따른 red pine 리그노셀룰로오스 용매열액화반응의 바이오매스 전환율과 수산가 및 산가를 나타낸 것이다:(a) 바이오매스 전환율, (b) 수산가 및 산가(■: 수산가,

: 산가)
도 4는 EFB 리그닌의 액화공정에 대한 바이오매스 로딩량의 영향을 나타낸 것이다.(바이오매스 전환율(■), 수산가(●) 및 산가(○)).
도 5는 EFB 리그닌의 액화공정에 대한 반응 온도의 영향을 나타낸 것이다.(바이오매스 전환율(■), 수산가(●) 및 산가(○)).
도 6은 EFB 리그닌의 액화공정에 대한 산 촉매 로딩량의 영향을 나타낸 것이다.(바이오매스 전환율(■), 수산가(●) 및 산가(○)).
도 7은 EFB 리그닌의 액화공정에 대한 반응 시간의 영향을 나타낸 것이다.(바이오매스 전환율(■), 수산가(●) 및 산가(○)).
도 8은 EFB 당화 잔사 리그닌의 액화공정에 대한 바이오용매의 형태와 PEG#400의 첨가의 영향을 나타낸 것이다:(a) 바이오매스 전환율, (b) 수산가, (c) 산가(■: Bio-BD 단일 용매,

: Bio-BD/PEG#400 혼합 용매).
도 9는 EFB 리그닌 부산물(a, L0), EFB 리그닌 유래 바이오폴리올(a), 바이오폴리올 유래 바이오폴리우레탄(b)의 FT-IR 분석 결과 그래프이다. (L1, PU1: 1,4-BD, L2, PU2: 2,3-BDL, L3, PU3: 2.3-BDM. (b)에서 회색선은 BD/PEG400# 혼합용매).Fig. 1 shows bioplastics standards and certification labels by country.
FIG. 2 shows the biomass conversion rate, the acid value and the acid value of the kraft lignin solvent thermal liquefaction reaction according to the biobutanediol isomer: (a) biomass conversion rate, (b)

: Acid value)
FIG. 3 shows the biomass conversion rate, the acid value and the acid value of the red pine lignocellulose solvent thermal liquefaction reaction according to the biobutanediol isomer: (a) biomass conversion rate, (b)

: Acid value)
Figure 4 shows the effect of biomass loading on the liquefaction process of EFB lignin. (Biomass conversion rate (?), Water acid value (?) And acid value (?)).
Figure 5 shows the effect of reaction temperature on the liquefaction process of EFB lignin. (Biomass conversion rate (?), Water acid value (?) And acid value (?)).
Figure 6 shows the effect of acid catalyst loading on the liquefaction process of EFB lignin. (Biomass conversion rate (?), Water acid value (?) And acid value (?)).
Figure 7 shows the effect of reaction time on the liquefaction process of EFB lignin. (Biomass conversion rate (?), Water acid value (?) And acid value (?)).
Figure 8 shows the effect of the addition of PEG # 400 and the form of the biosolvent on the liquefaction process of EFB saccharified residual lignin: (a) biomass conversion rate, (b) Single solvent,

: Bio-BD / PEG # 400 mixed solvent).
9 is a graph of FT-IR analysis results of EFB lignin byproduct (a, L0), EFB lignin-derived biopolyol (a) and bio polyol derived bio polyurethane (b). (Gray line in BD / PEG400 # mixed solvent) in 2.3-BDM (2.3-BDM) (L1, PU1: 1,4-BD, L2, PU2: 2,3-BDL, L3 and PU3.

In the present invention, EFB lignin as a by-product of the saccharification process is liquefied under a sulfuric acid catalyst, 1,4-BD as a biosolvent is used to increase the proportion of raw materials derived from bio, and PEG # 400 is mixed as a cosolvent, Respectively. The reaction conditions were optimized by analyzing the effect of 1,4-BD and PEG # 400 ratio, biomass addition amount, acid catalyst addition amount, reaction temperature and reaction time. In addition, the use of three of the isomers of butanediol, 1,4-BD, 2,3-BDL and 2,3-BDM as a single solvent, or a solvent in which PEG # 400 was mixed in each butane diol After the heat liquefaction reaction was carried out, these were compared and analyzed. In addition, kraft lignin and red pine lignocellulose with different types of biomass were subjected to solvent thermal liquefaction reaction using 1,4-BD, 2,3-BDL and 2,3-BDM as a single solvent. And the applicability of the present invention was examined.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided to further understand the present invention, and the present invention is not limited by the examples.

Example  One: EFB  Lignin Solvent heat  Liquefaction reaction

EFB lignin was liquefied using a 100 mL three-necked reactor and a temperature-controllable heating mantle with stirring at 200 RPM under mild temperature (100-170 DEG C) and atmospheric conditions. 30 g of a reaction solvent was added to the reactor, and EFB lignin was added under the condition of adding 5 to 35% by weight of biomass to the weight of the solvent. For the reaction solvent, 1,4-BD, 2,3-BDL and 2,3-BDM were used as main solvents and PEG # 400 was used as a solvent in a ratio of 10% by weight. The reaction solution in the reactor was preliminarily heated for 1 hour, and then 98% sulfuric acid catalyst was added slowly under the condition of 0-5 wt% of the acid catalyst to the weight of the reaction solvent. The reaction was then allowed to proceed for a reaction time of 5 to 180 minutes. After completion of the reaction, the reaction solution was cooled to room temperature using cold water to obtain a lignin-derived bio-polyol.

Experimental Example  One : Biomass  Conversion rate analysis

The lignin biopolyol sample was weighed at a weight of about 10% by weight based on the weight of the solvent used in the reaction solution in which the reaction was terminated according to Example 1. The weighed samples were washed with 50 mL of 95% ethanol and then centrifuged at 10,000 RPM for 15 minutes to separate the solid layer. The separated solid layer was washed once more with ethanol in the same manner and then further washed with deionized water. After pre-drying in a 105 ° C drying oven, the washed specimens were filtered using weighed filter paper and the filter paper with the remaining solid residue was dried in a 105 ° C drying oven for 24 hours. The weight of the dried filter paper was measured and the biomass conversion rate was calculated using the following equation (1). After two experiments in the same way for the correct conversion rate analysis, the average was calculated as the biomass conversion rate.

[Formula 1]

Biomass  Conversion rate % ) = 100 - (((W _One -W ₂ ) / W ₃ ) * W ₄ / W ₅ * 100)

W ₁ : Total weight of dried solid residue and filter paper

W ₂ : Weight of dried filter paper

W ₁ -W ₂ : Weight of dried solid residue

W ₃ : Weight of weighed lignin bio polyol sample

W ₄ : Total weight of lignin bio-polyol obtained through liquefaction process

(W ₁ -W ₂ ) / W ₃ ) * W ₄ : Total weight of solid residue in the whole lignin biopolyol

W ₅ : Weight of biomass used in liquefaction process

Experimental Example  2: fish price and Acid value  analysis

The hydroxyl value of the EFB lignin bio-polyol prepared in Example 1 according to ASTM D4274-05D standard was analyzed. 25 g of the esterifying agent was added to 2 g of the EFB lignin biopolyol sample, and the mixture was stirred at 100 캜 for 15 minutes to conduct the esterification reaction. After cooling to room temperature, the solution was titrated to pH 8.0 with 0.5 N aqueous sodium hydroxide solution.

For acid value analysis, 1 g of EFB lignin bio-polyol sample was analyzed according to ASTM D4662-08 standard.

Each sample was dissolved in 50 mL of ethanol and titrated to pH 8.0 with 0.1 N aqueous sodium hydroxide solution. For accurate measurement, all samples were measured twice, and the average was calculated as the fisheries value and the mountain range.

Example  2: Bio Butanediol  Kraft lignin according to isomer Solvent heat liquefaction reaction

Kraft lignin from Sigma-Aldrich was used as the biomass. As a reaction solvent, isomers of butanediol 1,4-butanediol (1,4-BD), 2,3-butanediol levo type (2,3-BDL), 2,3-butanediol messo type ) Was used as a single solvent, and the reaction was carried out under the conditions of a feed amount of 25 wt% of biomass, a reaction temperature of 100 ° C, an amount of acid catalyst of 3 wt%, and a reaction time of 120 minutes. The acid value was evaluated and the results are shown in Fig.

Biomass conversion was obtained with 70.38% using 1,4-BD, 76.40% using 2,3-BDL, and 72.85% using 2,3-BDM. In conclusion, 2,3-BDL showed the highest biomass conversion rate. From this, it can be seen that when kraft lignin is used as biomass, 100% bio-derived polyol having a biomass conversion higher than 70% can be produced.

There was no significant difference in the hydroxyl number between 898.54 mg KOH / g and 887.64 mg KOH / g when 2,3-BDL and 2,3-BDM were used, but when 1,4-BD was used, 813.98 mg KOH / g and slightly different from 2,3-BD. The results showed that the characteristics of the bio - polyol were different depending on the kind of isomers of butanediol.

In the case of acid number, 14.56 mg KOH / g was used for 1,4-BD, 16.37 mg KOH / g was used for 2,3-BDL and 15.29 mg KOH / g was used for 2,3-BDM. The higher the biomass conversion rate, the higher the acid value, which is the result of the acid compound being produced by the decomposition of lignin.

Example  3: Bio Butanediol  Red pine according to the isomer Lignocellulose Solvent heat liquefaction reaction

P. densiflora derived from red pine wood as biomass Lignocellulose was used. A reaction mixture containing 15% by weight of biomass, reaction temperature of 130 ° C, and 3% by weight of 1,4-BD, 2,3-BDL and 2,3-BDM, which are isomers of butanediol, And the reaction temperature was 60 minutes, the conversion of biomass, the acid value and the acid value of the biomass were evaluated, and the results are shown in FIG.

The biomass conversion was obtained as 29.98% for 1,4-BD, 53.57% for 2,3-BDL and 53.52% for 2,3-BDM. There was no significant difference between 2,3-BD and 1,4-BD, which showed a low biomass conversion rate of about 30%. It can be seen from the results that the red pine lignocellulose has a large influence on the biomass conversion rate of the isomer of butanediol. Red pine wood, P. densiflora When lignocellulose was used as a biomass and subjected to solvent heat liquefaction reaction with biobutanediol, a biomass conversion rate of 50% or more was obtained.

The highest acid value (23.44 mg KOH / g) and the lowest acid value (808.3 mg KOH / g) of the levo type butanediol were found to be similar in all three types of butanediol, Respectively. Based on the above results, it is considered appropriate to carry out the liquefaction reaction using levo type butane diol which shows a high biomass conversion rate.

Example  4: Biopolyurethane  synthesis

Bio - polyurethane derived from lignin bio - polyol was synthesized in 50 mL beaker. 5 g of lignin bio-polyol was added to a 50 mL beaker and pre-heated in an oil bath at 100 ° C. After preliminary heating, toluene diisocyanate (TDI) was slowly added with stirring at a 1: 1 equivalent ratio to the hydroxyl groups of the lignin biopolyol. The magnetic stirrer was reacted until it could no longer move, and then crosslinked in a 105 ° C oven for 12 hours through curing.

Experimental Example 3: Effect of mixing ratio of 1,4-butanediol and PEG # 400

The present invention uses 1,4-BD as a main solvent capable of being produced as a bio-solvent through bioconversion in order to replace a solvent derived from petroleum resources, which is generally used as a solvent for thermal liquefaction of lignin, PEG # 400 was used as a humectant. The biomass conversion rates when using 1,4-BD as a single solvent and when increasing the ratio of PEG # 400 were not significantly different from 54.7 to 59.7%. The acid value increased slightly from 18.9 mg KOH / g to 24.5 mg KOH / g as the mixing ratio of crude oil was increased. This is analyzed as a result of the increase of the phenolic acid compound due to the decomposition of EFB lignin by the quasi-solvent PEG # 400 during the liquefaction reaction. The ratio of PEG # 400 having a small amount of hydroxyl groups per unit weight was increased from 976.6 mg KOH / g to 410.0 mg KOH / g, compared with 1,4-BD. Based on these results, the optimum mixing ratio was selected as 9/1 (w / w) ratio which can minimize the amount of PEG # 400, which is a petroleum resource-derived material, and high biomass conversion rate. The results are summarized in Table 1 below.

Experimental Example  4: Biomass  Influence of loading amount

The effect of the amount of EFB lignin used as biomass on the liquefaction efficiency was examined. For this purpose, biomass conversion rate, acid value and water acid value evaluation experiment according to biomass loading amount were carried out, and the results are shown in FIG. As shown in FIG. 4, the biomass conversion rate tended to decrease with an increase in the amount of biomass, which is considered to be due to an insufficient amount of the active solvent compared to the increased biomass loading. As the biomass loading increased from 5 wt% to 25 wt%, the biomass conversion decreased slightly from 55.6% to 49.3% and decreased sharply from 25 wt%. Fishery prices did not show a significant change with increasing biomass quantity. The acid value tended to decrease from 21.9 mg KOH / g to 12.1 mg KOH / g as the amount of biomass increased. In general, acidic compounds are produced by the decomposition reaction of lignin, which can be seen as a result of a decrease in the decomposition reaction due to the decrease in the biomass conversion rate due to the increase in the biomass amount. Based on these results, the optimum biomass loading condition was determined as 25% by weight of biomass conversion ratio and low acid value compared to biomass amount.

Experimental Example  5: Effect according to reaction temperature

Generally, high temperature accelerates the liquefaction of lignin, but since EFB lignin pyrolysis occurs at 250 ° C or higher, an experiment for evaluating biomass conversion rate, acid value and water acid value according to the reaction temperature in the temperature range of 100 to 170 ° C was carried out, 5. As the reaction temperature increased from 100 ℃ to 150 ℃, the biomass conversion rate increased from 49.3% to 63.3%. This is the result of accelerated liquefaction of lignin due to temperature increase. When the reaction temperature was 170 ℃, the biomass conversion rate decreased sharply to 39.3%. It is considered that this is the result of the repolymerization reaction between the active functional groups of the degraded lignin. In the case of fisheries value, the tendency was shown to decrease with increasing reaction temperature, and it tended to decrease rapidly when reaction temperature was above 150 ℃. This is also the result of the repolymerization of the lysine decomposed. In the case of acid value, the tendency to increase with increasing reaction temperature showed a tendency to increase rapidly from the reaction temperature of 150 ° C or higher. This is because the lignin decomposition reaction is accelerated by the high reaction temperature and the amount of the acid compound is increased. Based on the results, the optimum reaction temperature was determined as 150 ° C.

Experimental Example  6: Effect of acid catalyst loading

The acid catalyst decomposes EFB lignin into small molecules, accelerating the esterification reaction between the liquefying solvent and lignin, which is a polyhydric alcohol, and accelerating the liquefaction of lignin. However, the use of a high concentration of acid catalyst increases the acid value of the bio-polyol, which adversely affects the physical properties of the bio-plastic, and promotes the repolymerization of the degraded low molecular weight lignin, thereby reducing the biomass conversion. In consideration of this, the amount of the acid catalyst loaded was changed from 0 wt% to 5 wt% based on the weight of the reaction solvent, and the biomass conversion rate, acid value and water acid value evaluation experiment were performed according to the acid catalyst loading amount. In the case of the biomass conversion rate, the amount of acid catalyst rapidly increased from 27.9% to 63.3% as the amount of the acid catalyst increased to 3% by weight, and decreased rapidly thereafter to 44.0% at 5% by weight. This is the result of promoting the repolymerization of low molecular weight lignin liquefied by a high concentration of acid catalyst. As the amount of acid catalyst increased, the acid value decreased from 929.9 mg KOH / g to 471.1 mg KOH / g. These results suggest that the esterification reaction is promoted by the increase of the amount of the acid catalyst. As the amount of acid catalyst increased, the acid value increased from 1.4 mg KOH / g to 48.9 mg KOH / g, which is a natural result due to the use of an acid compound as a catalyst. Based on these results, the optimum condition of the acid catalyst loading amount was selected as 3 wt%.

Experimental Example  7: Effect of reaction time

The effect of the reaction time change on the liquefaction process is shown in FIG. 7, based on the amount of biomass loading, the reaction temperature, and the acid catalyst loading amount optimized through the liquefaction process according to the change in conditions. The biomass conversion rate increased to 63.3% as the reaction time increased to 120 min, and the biomass conversion rate rapidly decreased to 27.6% under the reaction time of 180 min. These results suggest that the polymerization reaction accelerates as the reaction time increases over 120 min. In the case of acid value, the reaction time was slightly increased from 16.8 mg KOH / g to 21.7 mg KOH / g as the reaction time increased up to 120 minutes. In the case of the acid value, the tendency was drastically decreased from 845.7 mg KOH / g to 582.7 mg KOH / g It looked. After 120 minutes, the acid value increased sharply to 54.4 mg KOH / g and the fishery value did not change much near 579.0 mg KOH / g. When the reaction time is 120 minutes or less, esterification reaction between 1,4-BD and hydroxyl group of EFB lignin is predominant, but after 120 minutes, the esterification reaction can not be continued due to lack of active solvent, And decomposition reaction and condensation reaction of lignin by heat were more active. Based on the results, the optimal reaction time was determined to be 120 minutes when the biomass conversion rate was considered.

Experimental Example  8: Butanediol  Effect of morphology and PEG # 400 mixing

Experiments were carried out under the optimized reaction conditions of butane diol isomers in which the butane diol isomers, in which PEG # 400 was mixed at a ratio of 10 wt%, as solvents, The effect of the addition of PEG # 400 on the liquefaction process was confirmed. Fig. 8 shows the results thereof.

When the respective butanediol isomers were used as a single solvent, there was no significant change in the acid value and the acid value (FIG. 8 (b, c) black bars). The biomass conversion rate increased to 68.9% and 65.3% when 2,3-BDL and 2,3-BDM were used as a single solvent (Fig. 8 (a), black bar).

When the PEG # 400 was mixed with each of the butane diol isomers, the conversion rate of 1,4-BD increased sharply from 49.1% to 63.3%, and 2,3-BDL and 2,3-BDM (66.9%) and 59.7% (Fig. 8 (a)).

In the case of aquatic fish, the proportion of PEG # 400 with a small amount of hydroxyl groups relative to the molecular weight was increased and the fisheries value tended to decrease. In the case of 2,3-BDL / PEG # 400 and 2,3-BDM / PEG # 400, 702.9 mg KOH / g and 716.8 mg KOH / g were used for 1,4-BD / PEG # / g, there was no significant difference between 2,3-BDL and 2,3-BDM. As a result, it can be seen that when the butanediol / PEG # 400 mixed solvent is used, the decomposition reaction and the esterification reaction of lignin are more greatly affected by the chemical structure difference between 1,4-BD and 2,3-BD (Fig. 8 (b), gray bar).

In the case of using 1,4-BD as a single solvent and 1,4-BD / PEG # 400 mixed solvent, the acid value was 17.5 mg KOH / g for 1,4-BD, 1,4 In the case of BD / PEG # 400, 21.7 mg KOH / g, the PEG # 400 mixed solvent was higher and the acid value of 2,3-BDL and 2,3-BDM was slightly increased or decreased. This is presumed to be the result of accelerated decomposition reactions such as solvent solvolysis by a similar chemical structure between 1,4-BD and PEG # 400 (FIG. 8 (c)). As a result, in the case of 2,3-BDL, high biomass conversion rate of 68.9% was obtained even when used as a single solvent without the use of quasi-solvent PEG # 400. It is expected that 2,3-BDL will be applied as the most suitable solvent when synthesizing 100% bio-derived bio-polyol without using petroleum-derived raw materials.

Example  5: EFB  Lignin Bio polyol  origin Bio-polyurethane  synthesis

BD-PEG # 400 (PU1 / P), 2,3-BDL / PEG # Polyurethane synthesized by polymerizing EFB lignin-derived biopolyol and toluene diisocyanate (TDI), which were prepared by using PF3 / 400 (PU2 / P) and 2,3-BDM / PEG # And analyzed by FT-IR. The results are shown in Fig.

When the spectrum of FIG. 9 (b), which is an FT-IR result, was analyzed, it was confirmed that the bio-polyurethane-related spectrum shown in Table 2 was present. The FT-IR spectra of FIGS. 9 (a) and 9 (b) show that the hydroxyl group bands of 3600-3000 cm ^-1 decrease, indicating that the hydroxyl groups of the bio- . From the above results, the synthesis of bio - polyurethane was confirmed by using bio - polyol derived from EFB lignin.

When the FT-IR spectra of the PU (color line) and PU / P (gray line) in FIG. 9 (b) are compared, there is a difference in the 2980-2854 cm ^-1 band indicating CH ₂ bonding. This can be seen as a result of PEG # 400 containing a large amount of CH ₂ bonds. The FT-IR spectra of PU1 (red line) and PU / P (PU1, gray line) show differences in the 1270-1000 cm- ¹ band indicating ether bonding. This can be seen as a result of PEG # 400 containing a large amount of ether bond. In contrast, no significant difference was observed between PU2 and PU3, indicating that mixing PEG # 400 with 1,4-BD influences lignin liquefaction. The 2225 cm ^-1 peak indicating the NCO bond of the remaining unreacted TDI appears different depending on the solvent used. The effect of PEG # 400 on the degree of polymerization of the bio-polyurethane is different depending on the type of butanediol isomer used . As a result, the effect of addition of PEG # 400 on the liquefaction reaction or polymerization reaction was different depending on the type of butane diol.

EFB lignin by-products were liquefied through solvent thermal liquefaction using 1,4-BD mixed with 10% by weight of PEG # 400 relative to the total weight of the solvent, and biomass loading amount of 25 wt% %, A reaction temperature of 150 ° C, an acid catalyst loading of 3%, and a reaction time of 120 minutes. Biomass conversion rate of 63.3% was obtained at the optimum condition. In addition, bio-polyurethane was synthesized by polymerizing TDI with EFB lignin-derived bio-polyol, and confirmed by FT-IR analysis. Three types of butane diol isomers were used as a single solvent or each was mixed with a quencher PEG # 400 as a liquefaction solvent. As a result, PEG # 400, a petroleum resource-derived material, was used as a quencher in the case of 2,3-BDL The biomass conversion rate was as high as 68.9%. It was confirmed that the use of 2,3-BDL and EFB lignin can reduce the dependence of petroleum resources on the production of bio-polyols and bio-polyurethanes, and it is possible to produce environmentally friendly plastics.

Claims (11)

A first step of synthesizing a lignin-derived polyol liquefied by liquefaction reaction of lignin and a first solvent under an acid catalyst condition; And
And a second step of synthesizing a polyurethane through polymerization reaction with the second solvent from the polyol. The method of claim 1, wherein the lignin of the first stage is selected from the group consisting of Empty Fruit Bunches lignin, Kraft lignin, lignocellulose, lignosulfonate, Organosolv lignin, ), Steam explosion lignin or weak acid lignin. The method according to claim 1, wherein the amount of lignin used in the first step is 5 to 35% by weight based on the total weight of the solvent. The method of claim 1, wherein the first solvent is selected from 1,4-butanediol, levo-2,3-butanediol, meso-2,3-butanediol, and dextro-2,3- Lt; RTI ID = 0.0 > butanediol. ≪ / RTI > 5. The method according to claim 4, wherein the butadiol is bio-butanediol (bio-BD) produced through a biological process using recombinant Escherichia coli. The method of claim 4, wherein the first solvent is selected from the group consisting of PEG 200 (polyethylene glycol 200, MW: 190-210 g / mol), PEG 300 (polyethylene glycol 300, MW: 285-315 g / mol) glycol 400, MW: 380 to 420 g / mol) relative to the total weight of the first solvent. The process according to claim 1, wherein the liquefaction reaction in the first stage is carried out at 100 to 170 占 폚. The process according to claim 1, wherein the liquefaction reaction of the first stage is carried out for 5 to 180 minutes. The method of claim 1, wherein the second solvent is selected from the group consisting of toluene diisocyanate (TDI), methylene diphenyl diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, But are not limited to, xylylene diisocyanate, tetramethylene diisocyanate, cyclohexylene diisocyanate, dicyclohexylmethane 4,4'-diisocyanate, dicyclohexylmethane diisocyanate, Poly (hexamethylene diisocyanate), poly (propylene glycol) tolylene 2,4-diisocyanate terminated, poly (propylene glycol) tolylene 2,4-diisocyanate terminated, Telechelic isocyanate-terminated < RTI ID = 0.0 > polybutadiene). The production method according to claim 1, wherein the bio-polyurethane has a biomass content of 25% or more and meets ASTM D6366 standard. A bio-polyurethane produced according to any one of claims 1 to 10, wherein the biomass content is 25% or more and meets the ASTM D6366 standard.

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