Synthesis method of sugar alcohol
阅读说明：本技术 一种糖醇的合成方法 (Synthesis method of sugar alcohol ) 是由 曾宪海 张良清 邱佳容 高哲邦 林鹿 唐兴 孙勇 于 2019-10-15 设计创作，主要内容包括：本发明公开了一种糖醇的合成方法,包括：将木糖或葡萄糖、磁性催化剂和去离子水加入反应釜中,然后密封反应釜,在1-8MPa的氢气气氛下和500-700rpm的搅拌速率下,于100-180℃进行密闭反应0.5-5h,再冷却至室温,即得所述糖醇；上述磁性催化剂经磁性分离和清水洗涤后,用于下次反应。本发明的糖醇的产率高,可调节反应温度和金属比例等条件获得高纯度、高得率的单一糖醇或者获得高得率和高附加值的混合糖醇。(The invention discloses a synthesis method of sugar alcohol, which comprises the following steps: adding xylose or glucose, a magnetic catalyst and deionized water into a reaction kettle, then sealing the reaction kettle, carrying out closed reaction at 180 ℃ for 0.5-5h under the hydrogen atmosphere of 1-8MPa and the stirring speed of 500 plus 700rpm, and then cooling to room temperature to obtain the sugar alcohol; the magnetic catalyst is used for the next reaction after being magnetically separated and washed by clear water. The method has high yield of the sugar alcohol, and can obtain single sugar alcohol with high purity and high yield or mixed sugar alcohol with high yield and high added value by adjusting conditions such as reaction temperature, metal ratio and the like.)
1. A method for synthesizing sugar alcohol is characterized in that: the method comprises the following steps: adding xylose or glucose, a magnetic catalyst and deionized water into a reaction kettle, then sealing the reaction kettle, carrying out closed reaction at 180 ℃ for 0.5-5h under the hydrogen atmosphere of 1-8MPa and the stirring speed of 500 plus 700rpm, and then cooling to room temperature to obtain the sugar alcohol; the magnetic catalyst is used for the next reaction after being magnetically separated and washed by clear water;
the preparation method of the magnetic catalyst comprises the following steps:
(1) dissolving active metal precursor containing cation concentration of 0.8-1.2mol/L in proper amount of deionized water, and slowly adding dropwise the solution into equal volume of NaOH and Na with pH of 8-102CO3Aging in the mixed solution at 50-70 deg.C for 10-15 hr, adding NaOH and Na2CO3The molar ratio of the anion in the mixed solution to the cation in the active metal precursor is 2.05-0.6: 1, and the above-mentioned NaOH and Na2CO3CO in the mixed solution3 2-And OH-The molar ratio of (A) to (B) is 1: 20-26;
(2) carrying out solid-liquid separation on the material obtained in the step (1) to obtain a precipitate, and washing the precipitate with distilled water until the pH value is neutral;
(3) drying the material obtained in the step (2) at the temperature of 105-112 ℃ for 12-18h, then grinding the material into powder, sieving the powder by a sieve with 90-110 meshes, and introducing hydrogen into a reduction furnace at the temperature of 350-550 ℃ for reduction for 3-5h to obtain the magnetic catalyst;
the active metal consists of Ni and Fe, or Ni and Al, or Ni, Fe and Cu.
2. The method of synthesis of claim 1, wherein: the active metal consists of Ni and Fe in a molar ratio of 4-22: 1, and the temperature of the reduction furnace in the step (3) is 380-420 ℃.
3. The method of synthesis of claim 1, wherein: the active metal consists of Ni and Al in a molar ratio of 6-9: 1, and the temperature of the reduction furnace in the step (3) is 480-520 ℃.
4. The method of synthesis of claim 1, wherein: the active metal consists of Ni, Fe and Al in a molar ratio of 0.5-8: 0.2-1.5: 1-3, and the temperature of the reduction furnace in the step (3) is 480-520 ℃.
5. The method of synthesis of claim 1, wherein: the active metal consists of Ni, Fe and Cu in a molar ratio of 6-8: 1: 0.75-1.5, and the temperature of the reduction furnace in the step (3) is 480-520 ℃.
6. The method of synthesis according to any one of claims 1 to 5, wherein: the mass ratio of the xylose or the glucose to the deionized water is 0.5-2: 15-50.
7. The method of synthesis according to any one of claims 1 to 5, wherein: the mass ratio of the magnetic catalyst to the xylose or the glucose is 0.2-1: 5.
8. A synthesis process according to any one of claims 1 to 3, characterized in that: the active metal precursors of Ni, Fe, Al and Cu are nickel nitrate, ferric nitrate, aluminum nitrate and copper nitrate in sequence.
Technical Field
The invention belongs to the technical field of sugar alcohol preparation, and particularly relates to a synthesis method of sugar alcohol.
Background
Xylitol and sorbitol are among the 12 most important target chemicals specified by the energy response center of the U.S. department of energy. Mannitol is a pharmaceutically good diuretic, and mannitol has little moisture absorption, and can be used as an excipient for tablets. Arabitol reduced after isomerization of xylose or directly reduced by arabinose is rare sugar alcohol, is used in microbial fermentation and gene improvement tests, and is used for synthesizing an important medical intermediate, namely L-ribose with anti-AIDS, anti-virus and anti-cancer drugs; the arabitol can also be used for preparing arabinose reactive essence which can generate soft and rich aroma flavor. Sugar alcohols are widely used in the food industry as one of the ingredients of candy, ice cream fillings, hard candy and sugar-free chewing gum. In addition, sugar alcohols have prebiotic effects as functional sweeteners, lowering triglyceride, cholesterol levels and blood glucose. More importantly, sugar alcohol is a very key energy intermediate chemical used for converting into various high-value chemicals, such as ethylene glycol, propylene glycol, pentane, 1, 3-pentadiene, glycerol, sugar acid, furan compounds, lactic acid and the like.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for synthesizing sugar alcohol.
The technical scheme of the invention is as follows:
a method of synthesizing a sugar alcohol comprising: adding xylose or glucose, a magnetic catalyst and deionized water into a reaction kettle, then sealing the reaction kettle, carrying out closed reaction at 180 ℃ for 0.5-5h under the hydrogen atmosphere of 1-8MPa and the stirring speed of 500 plus 700rpm, and then cooling to room temperature to obtain the sugar alcohol; the magnetic catalyst is used for the next reaction after being magnetically separated and washed by clear water;
the preparation method of the magnetic catalyst comprises the following steps:
(1) dissolving active metal precursor containing cation concentration of 0.8-1.2mol/L in proper amount of deionized water, and slowly adding dropwise the solution into equal volume of NaOH and Na with pH of 8-102CO3Aging in the mixed solution at 50-70 deg.C for 10-15 hr, adding NaOH and Na2CO3The molar ratio of the anion in the mixed solution to the cation in the active metal precursor is 2.05-0.6: 1, and the above-mentioned NaOH and Na2CO3CO in the mixed solution3 2-And OH-The molar ratio of (A) to (B) is 1: 20-26;
(2) carrying out solid-liquid separation on the material obtained in the step (1) to obtain a precipitate, and washing the precipitate with distilled water until the pH value is neutral;
(3) drying the material obtained in the step (2) at the temperature of 105-112 ℃ for 12-18h, then grinding the material into powder, sieving the powder by a sieve with 90-110 meshes, and introducing hydrogen into a reduction furnace at the temperature of 350-550 ℃ for reduction for 3-5h to obtain the magnetic catalyst;
the active metal consists of Ni and Fe, or Ni and Al, or Ni, Fe and Cu.
In a preferred embodiment of the present invention, the active metal consists of Ni and Fe at a molar ratio of 4-22: 1, and the temperature of the reduction furnace in the step (3) is 380-420 ℃.
In a preferred embodiment of the present invention, the active metal consists of Ni and Al in a molar ratio of 6-9: 1, and the temperature of the reduction furnace in the step (3) is 480-520 ℃.
In a preferred embodiment of the present invention, the active metal consists of Ni, Fe, Al in a molar ratio of 0.5-810.2-1.5: 1-3, and the temperature of the reduction furnace in the step (3) is 480-.
In a preferred embodiment of the present invention, the active metal is composed of Ni, Fe, Cu at a molar ratio of 6-8: 1: 0.75-1.5, and the temperature of the reduction furnace in the step (3) is 480-520 ℃.
In a preferred embodiment of the invention, the mass ratio of xylose or glucose to deionized water is 0.5-2: 15-50.
In a preferred embodiment of the invention, the mass ratio of the magnetic catalyst to xylose or glucose is 0.2-1: 5.
In a preferred embodiment of the present invention, the active metal precursors of Ni, Fe, Al, and Cu are nickel nitrate, iron nitrate, aluminum nitrate, and copper nitrate, in that order.
The invention has the beneficial effects that:
1. the method has high yield of the sugar alcohol, and can obtain single sugar alcohol with high purity and high yield or mixed sugar alcohol with high yield and high added value by adjusting conditions such as reaction temperature, metal ratio and the like.
2. The metal precursor used by the magnetic catalyst is non-noble metal, the preparation cost is low, the magnetic catalyst has superparamagnetism, the magnetization intensity is high, and the recovery is very quick and convenient.
3. The preparation method of the magnetic catalyst is simple, and excellent activity is kept in the recycling process.
Detailed Description
The technical solution of the present invention is further illustrated and described by the following detailed description.
The preparation method of the magnetic catalyst in the following examples comprises:
the active metal precursor with 1mol/L cation concentration is dissolved in 350mL deionized water and slowly added dropwise to 350mL NaOH and Na2CO3In the mixed solution, the pH of the solution was maintained between 8.0 and 10, the resulting slurry was aged at 60 ℃ for 12 hours, and then the precipitate was filtered and washed thoroughly with distilled water until the pH was neutral. Drying at 105 ℃ for 15h, grinding and sieving by a 100-mesh sieve, introducing hydrogen into a reduction furnace for reduction for 4h to prepare the magnetic catalyst, wherein the active metal consists of Ni and Fe, or consists of Ni and Al, or consists of Ni, Fe and Cu, and when the active metal consists of Ni and Fe, the temperature of the reduction furnace is 380-420 ℃, and the rest is 480-520 ℃;
the active metal precursors of Ni, Fe, Al and Cu are nickel nitrate, ferric nitrate, aluminum nitrate and copper nitrate in sequence.