KR930001390B1 - Process for the preparation of glucose - Google Patents

Abstract

A monosaccharide is prepd. by (a) mixing the cellulose material, e.g. rice straw, barley straw, wheat straw, Yucca cellulose etc., with 15-21 % HCL soln., (b) reacting the mixt. at 100-110 deg.C for 5-8 hrs., (c) filtering the reacted mixt. to obtain the soln., and (d) adding 0.01-0.04 mol AlCl3 or AlCl3 6H2O into the obtd. soln., re-reacting at 100-110 deg.C for 3- 4 hrs., netralizing with sodium hydroxide, delignificating and purifying to obtain the final product.

Description

Degradation and Extraction of Glucose-based Monosaccharides from Rice Straw, Barley Straw and Straw Pulp and Yucca Cellulose

The present invention is a novel method of decomposing and extracting glucose-based monosaccharides from rice straw, barley straw and straw pulp and Yucca cellulose.

As disclosed in the prior art filed by the applicant of the present application (1990 Korean Patent Application No. 5887), efforts to use pulp or pulp made from these grain waste materials or yucca cellulose obtained from a highly vivid yucca tree as a raw material of pulp or paper Although many attempts have been made so far, there have been many difficulties and limitations in the chemical or physical properties of these materials for use as a raw material for pulp or paper.

Due to this reality, one of the other practical uses of these wood materials is to use strong acids (such as 41% hydrochloric acid or 72% sulfuric acid) as solvents and wood materials (cellulose, hemicellulose and greenin) at reaction temperatures of 40-45 ° C. Completely dissolved and neutralized with alkali to precipitate and separate the ligrin, and the liquid component was separated by evaporation, and ethyl alcohol was attempted through the decomposition extraction of monosaccharides or a further step unit process.

However, the decomposition and extraction of monosaccharides containing glucose as a main component from woody materials using such strong acids is disadvantageous due to the practical risks of industrially handling strong acids and strong corrosiveness to production equipment. Nevertheless, the situation has left many problems in practical use or industrialization.

However, the present invention is another new method from 1990 Patent Application No. 5887 to solve the above-mentioned drawbacks of the conventional method, first, the hudroysis rate of rice straw cellulose so far 35-37% hydrochloric acid Contrary to the results of 50-55% having the highest yield when used as a hydrolysis solvent, the hydrolysis rate of cellulose can be increased by 70-75% using 15-21% hydrochloric acid.

Of course, the conventional method, unlike the condition that the reaction time was 20-30 hours at the reaction temperature of 40-45 ℃, in the present invention, the viscosity of the reaction time of 5-8 hours at the reaction temperature of 100 ℃ -110 ℃ also compared to the past There is no reason to be disadvantaged.

Second, in 1990 Patent Application No. 5887 associated with the present invention, hydrolysis and decomposition of cellulose into polysaccharides such as rice straw by hydrochloric acid was added by adding 0.05-0.20 mol of AlCl ₃ to 35-37% hydrochloric acid. Decomposition extraction of monosaccharides containing glucose from polysaccharides as a main component is carried out in one unit process, but in the present invention, rice straw cellulose deligignized with 15-21% hydrochloric acid solvent is reacted at a reaction temperature of 100-110 ° C. Hydrolysis under conditions of time 5-8 hours, first obtain a hydrolysis rate of cellulose of 70-75%, then separate the dihydrolyzed polysaccharide solution from the unhydrolyzed residue and add AlCl ₃ B to the polysaccharide solution. The concentration of AlCl _{3 in} AlCl ₃ · 6H ₂ O was added at 0.01-0.40 mol and the reaction temperature was heated again at 100-110 ° C. for 3-4 hours to complete the monosaccharide reaction (50-80% glucose) containing glucose as a main component. Letting room A.

At this time, when using a hydrochloric acid of 35-37% concentration by concentrating the polysaccharide solution, if the reaction temperature 40-45 ℃, the reaction time 2-3 hours can also be carried out the reaction with a monosaccharide containing 50-80% glucose.

On the other hand, another feature of the present invention, an acidic polysaccharide solution obtained by hydrolyzing delignined rice straw cellulose with hydrochloric acid at a concentration of 15-21%, yielding a hydrolysis yield of 70-75%, pH 4.5 After neutralizing with alkali to -4.8, the polysaccharide solution was converted into a disaccharide or a polysaccharide by a polysaccharide degrading enzyme under the trade name "Celluclast 1.5L" of NOVO ENZYME (Enzymes Divison, Novo Alle, DK-2880 Bagsvaerd, Denmark). The method of decomposing trisaccharides and decomposing them into monosaccharides containing glucose as a main ingredient using a decomposing enzyme under the trade name "Novozym 188", which is a disaccharide or trisaccharide cellobiase, is disclosed in 1990 Patent Application 5887. It is a different method from using monosaccharides and AlCl ₃ or AlCl ₃ · 6H ₂ O as decomposition catalysts.

Example 1

In this example, rice straw pulp, which has undergone delignification reaction through a general chemical digestion process (Kraft Process or Acetosolv Process, etc.), is used as a solvent using an aqueous hydrochloric acid solution at a concentration of 15-21% under normal pressure. Heat straw for 8 hours to decompose rice straw cellulose into polysaccharides. The decomposition rate of these celluloses into polysaccharides is about 70-75% by weight.

The residue was separated and removed from the polysaccharide dissolved in 15-21% aqueous hydrochloric acid solution, and the remaining hydrochloric acid-polysaccharide solution was used as a catalyst using AlCl ₃ or AlCl ₃ · 6H ₂ O at a concentration of 0.01-0.04, and the reaction temperature was 100-110 ° C. 3-4 hours or the remaining hydrochloric acid solution is concentrated to almost solid state, and 35-37% hydrochloric acid is added to it, and the reaction temperature is 40-45 ℃ for 2-3 hours to make glucose the main ingredient. Monosaccharide of polysaccharides is carried out.

Referring to the reaction of the present embodiment made at normal pressure again as follows. Organosolv cooking process, or acetic acid aqueous solution, in which rice straw, barley straw and straw having a dry water content of 10-15% are subjected to conventional kraft cooking process or delignination of these wood materials using alcohol as a solvent. The pulp is prepared by Acetosolv cooking process using a polyvinylated decomposition extract solution of cellulose (aqueous hydrochloric acid solution of 15-21% concentration) per 1g of the pulp sample, and a reflux condenser is attached at a ratio of about 10-20 kPa. In a round flask, the reaction temperature of 100-110 ° C and the reaction time of 5-8 hours were heated in an oil bath, and the binding ring of cellulose collapsed as in the reaction formula (1), resulting in a hydrolysis rate (polysaccharide rate) of 70. Obtain a solution of -75%.

Where R is H or glucose

This solution is separated from the cellulose residue which is not subjected to hydrolysis, and the monosaccharide reaction process containing glucose as a main component may be performed in the order described above.

After the monosaccharide reaction, the reaction solution is evaporated in vacuo to separate and remove 15-21% or 35-37% of hydrochloric acid used in the reaction, and the remaining hydrochloric acid is neutralized with caustic soda. In order to precipitate and separate the lignin and some AlCl ₃ and NaCl present in the stomach, and to remove excess Al ⁺⁺⁺ , Na ⁺ and Cl ^- ions contained in the supernatant as a sugar solution, a cation and anion exchange resin under the trade name "Dowex Pass through -50w ", pass diatomaceous earth and charcoal activated charcoal, remove other impurities in solution, decolorize and deodorize, concentrate and recover 50% or more of glucose, monosaccharide.

At this time, the yield of cellulose hydrolysis to polysaccharide and polysaccharide to glucose is highly influenced by the ratio of sample to solution, the concentration of catalyst used, and heating time.

First, the optimum reaction conditions for the decomposition reaction from cellulose to polysaccharides were 1g of sample to solution: 15cc or more, reaction temperature of 100 ℃ -110 ℃, and reaction time related to reaction temperature, but reaction temperature of 100- In the case of more than about 7 hours at 110 ℃, the hydrolysis rate of polysaccharides such as degrigated rice straw cellulose reached 70-75%, and secondly, the decomposition of decomposed polysaccharides into low molecular glucose again Experimental results showed that the yield of monosaccharides such as glucose was the highest when the ratio of concentrated polysaccharide solution to dissolved solution was 1 g: 15㏄ over 0.03 mol of catalyst, reaction temperature 40-45 ℃, and reaction time 3-4 hours. Able to know.

Tables 1 and 2 show the results obtained under the above optimum conditions.

TABLE 1

As shown in Table 1, the hydrolysis rate of hydrochloric acid, which is a hydrolysis solvent of cellulose, is dilute, that is, 15-21% shows that the hydrolysis rate is 20% higher than that of the 35-37% concentration.

In other words, the present invention shows that hydrolysis is much easier when the concentration of hydrochloric acid is dilute than 35-37%.

Table 2 shows the results of the monosaccharide reaction obtained by subjecting the AlCl ₃ catalyst to a polysaccharide solution having a hydrolysis rate of cellulose of 70-75%.

TABLE 2

As shown in Table 2, when the concentration of AlCl ₃ is 0.03 mol, the yields of glucose, maltose and fructose are the highest, and the amount of polysaccharide remaining unreacted as the concentration of AlCl ₃ is increased or decreased more than 0.03 mol. It can be seen that the result of this example shows that when the concentration of AlCl ₃ is 0.03 mol at concentration of 15-21% hydrochloric acid, reaction temperature 100-110 ° C., and reaction time 3-4 hours, Yield is the highest.

Example 2

In the case of using yucca cellulose, the chlorophyll component is present in the yucca leaf together with the yucca fiber. When the yucca leaf is deposited in hot water at 50-60 ℃, almost all of the chloroplast component is dissolved and the yucca cellulose remains solid. Cellulose can be separated from the yucca chlorophyll component.

All the procedure is the same as Example 1 except the procedure which cuts the obtained yucca cellulose about 0.3-0.4 cm in length, and uses it as a sample.

Only the hydrolysis rate from the yucca cellulose to polysaccharides is increased by 3-5% compared to that of rice straw cellulose.

Table 3 shows the results of this example.

TABLE 3

Example 3

After elution of the hydrolyzed solution of rice straw cellulose and yucca cellulose to primary polysaccharides, the concentration of hydrochloric acid is reduced significantly by vacuum evaporation. After neutralizing the pH to 4.5-4.8 with aqueous NaOH solution, hydrolysis of cellulose to polysaccharides is performed. A surplus of lignin is present at the time of precipitation, and the precipitated lignin is separated from the supernatant to obtain only the polysaccharide supernatant.

This supernatant is a polysaccharide degrading enzyme under the trade name "Celluclast 1.5L" of NOVO ENZYMES (Enzymes Division, Novo Alle, DK-2880 Bagsvaerd, Denmark) and "Novozym 188", a disaccharide or trisaccharide cellobiase. The disaccharide or trisaccharide is digested with an Iranian enzyme to complete a monosaccharide reaction containing glucose as a main component.

1% polysaccharide degrading enzyme "Celluclast 1.5L" is mixed in a test tube with 30% by weight of polysaccharide solution per 1g of polysaccharide decomposed from rice straw cellulose and yucca cellulose. After incubation (min) for 2 minutes, the disaccharide or trisaccharide reaction of polysaccharides, the enzyme "Novozym 188" was also added to 0.2% by weight percentage again and incubated again for 30-40 minutes to complete the reaction.

Table 4 shows the results of the above example.

TABLE 4

As shown in Table 4, it can be seen that when cellulose and disaccharides or trisaccharide degrading enzymes are used, it is possible to decompose monosaccharides containing very good glucose from rice straw cellulose or yucca cellulose.

Claims (1)

Hydrolyzed and dissolved 15-21% hydrochloric acid solution of wood cellulose, such as delignified rice straw, barley straw, straw and yucca cellulose, and aqueous hydrochloric acid solution per 100 g of cellulose, reaction temperature of 100-110 ° C, reaction time of 5-8 hours under normal pressure. The polysaccharide solution including the monosaccharide obtained by the hydrolysis reaction at a rate of 10-20 kPa was separated from the unreacted cellulose residue, whereby AlCl ₃ or AlCl ₃ · 6H ₂ O having a concentration in the range of 0.01-0.04 mol was obtained. When it is used as a monosaccharide decomposition catalyst, it is reacted for 3-4 hours at the reaction temperature of 100-110 ° C. to decompose it into a monosaccharide containing glucose as a main component, or when the polysaccharide solution is concentrated to use 35-37% of hydrochloric acid. It is characterized by decomposing the glucose into a monosaccharide mainly composed of glucose by reacting with AlCl ₃ having a concentration in the range of 0.01-0.04 moles as a catalyst for a reaction temperature of 40-45 ° C. and a reaction time of 2-3 hours. A method of extracting monosaccharides from vaginal substances.