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CN110845303A - Method for improving glucose hydrogenation efficiency - Google Patents

Method for improving glucose hydrogenation efficiency Download PDF

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Publication number
CN110845303A
CN110845303A CN201911209155.5A CN201911209155A CN110845303A CN 110845303 A CN110845303 A CN 110845303A CN 201911209155 A CN201911209155 A CN 201911209155A CN 110845303 A CN110845303 A CN 110845303A
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China
Prior art keywords
hydrogenation
glucose
solution
controlling
discharging
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CN201911209155.5A
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Chinese (zh)
Inventor
陈德水
谢绍勋
汪秀秀
毛学军
安延龙
程新平
廖承军
罗家星
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Zhejiang Huakang Pharmaceutical Co Ltd
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Zhejiang Huakang Pharmaceutical Co Ltd
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Priority to CN201911209155.5A priority Critical patent/CN110845303A/en
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/132Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
    • C07C29/136Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
    • C07C29/14Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Saccharide Compounds (AREA)

Abstract

The invention relates to a method for improving the hydrogenation efficiency of glucose, which comprises the following steps: firstly, adding a catalyst mixed solution and a glucose solution into a hydrogenation tank, then heating and hydrogenating, injecting alkali at the speed of 2-5L/min in the heating process, adjusting the pH value of the solution in the tank to 6.6-7.5, and continuously completing hydrogenation to obtain a glucose hydrogenated liquid. The method reduces the consumption of the catalyst, shortens the reaction time, improves the hydrogenation capacity of the glucose and reduces the cost.

Description

Method for improving glucose hydrogenation efficiency
Technical Field
The invention relates to the technical field of sorbitol production from glucose, and particularly relates to a method for improving the hydrogenation efficiency of glucose.
Background
Glucose, which can be obtained by physical, chemical and biological methods, is available as a variety of basic chemicals, such as sorbitol, lactic acid, levulinic acid, and the like. Among them, sorbitol is widely used as a compound with a high added value in the industries of food, medicine, daily chemicals and the like.
In industrial production, the Raney-Ni catalyst is mainly used for catalyzing the hydrogenation of glucose to prepare the sorbitol. The catalyst is characterized by high activity in neutral and alkalescent environments, nickel can be lost in an acid environment, and the activity of the catalyst is reduced; meanwhile, glucose can partially form fructose under the alkaline condition, and byproducts such as mannitol and the like are generated after hydrogenation, so that the initial system of the hydrogenation reaction is generally controlled to be neutral; however, in the reaction process, as the temperature rises, the pH value is reduced, the acidity is enhanced, the activity of the Raney-Ni catalyst is continuously reduced, the hydrogenation reaction time is increased, and the hydrogenation efficiency is obviously reduced.
In order to solve the problem, some catalysts are improved to improve the stability of the catalysts, for example, a patent with the publication number of CN106669681A introduces a reusable Ni/Cu/Al/Fe hydrotalcite-like precursor catalyst with magnetism, and various performances of the catalyst are improved by adding auxiliaries such as Fe, Cr, Mo, Co and the like into a Raney-Ni catalyst, so that the stability is improved. In addition, the glucose solution is adjusted to be neutral and weakly alkaline by adding alkali before the catalytic reaction, for example, in patent publication No. CN1214333A and patent publication No. CN109305882A, however, this method not only partially isomerizes the product glucose in the early stage of the reaction to produce mannitol and other by-products, but also in the middle and later stages of the reaction, the system is in an acidic environment, and thus the catalyst activity is reduced and the hydrogenation efficiency is low.
At present, there are studies to try to control the pH during the reaction, for example, patent publication No. CN109053368A discloses a method of adjusting the pH of the reaction system by adding magnesium powder during the reaction, but the actual effect of adding magnesium powder is not obvious during the hydrogenation of glucose, and it is difficult to transport and add magnesium powder in mass production.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for improving the hydrogenation efficiency of glucose, so as to solve the problems in the prior art that the pH value is continuously reduced along with the temperature rise in the hydrogenation process of glucose, the catalyst is in an acidic environment, nickel is lost, the activity of the catalyst is reduced, the hydrogenation reaction time is increased, and the hydrogenation efficiency is low.
The invention is realized by providing a method for improving the hydrogenation efficiency of glucose, which comprises the following steps:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55 +/-1% and the pH of 6.2 +/-0.2 into a hydrogenation tank;
step two, hydrogenation: and (3) heating and hydrogenating the glucose solution in the first step, controlling the pressure to be 6.5-10.5 MPa, controlling the temperature to be 110-140 ℃, starting to inject alkali at the speed of 2-5L/min when the temperature is 130-140 ℃, controlling the pH to be 6.6-7.5 after the alkali is injected, and controlling the whole hydrogenation time to be 200-230 min.
Step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
Compared with the prior art, the method for improving the glucose hydrogenation efficiency has the following characteristics:
(1) the process has the advantages of achieving the effect of stabilizing the activity of the catalyst in the hydrogenation reaction system, greatly reducing the loss phenomenon of the catalyst nickel, reducing the consumption of the catalyst, shortening the reaction time, reducing the cost of the catalyst by 25 percent, reducing the electric cost by 20 percent, reducing the steam cost by 10 percent and improving the hydrogenation capacity of glucose by 30 percent.
(2) The invention injects alkali in the reaction process, realizes the stability of pH in the hydrogenation process, ensures that the conversion rate of glucose is more than 99.8 percent, stabilizes the content of sorbitol in the hydrogenation solution to be more than 94.4 percent, and controls the content of mannitol to be less than 0.7 percent.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention discloses a method for improving the hydrogenation efficiency of glucose, which comprises the following steps:
step one, feeding: the catalyst mixed solution and glucose solution with the concentration of 55 plus or minus 1 percent and the pH value of 6.2 plus or minus 0.2 are added into a hydrogenation tank, and the volume of the feed liquid is 6.8 cubic.
Step two, hydrogenation: and (3) heating and hydrogenating the glucose solution in the first step, controlling the pressure to be 6.5-10.5 MPa, controlling the temperature to be 110-140 ℃, starting to inject alkali at the speed of 2-5L/min when the temperature is 130-140 ℃, controlling the pH to be 6.6-7.5 after the alkali is injected, and controlling the whole hydrogenation time to be 200-230 min.
Step three, discharging: and discharging to obtain hydrogenated liquid after the subsequent process is finished.
The catalyst mixed solution comprises nickel-aluminum alloy and low-concentration sorbitol solution, wherein the proportion of the nickel-aluminum alloy is 50%. And the alkali injection is any one of NaOH solution, KOH solution, sodium carbonate solution, sodium bicarbonate solution and magnesium hydroxide solution added into the hydrogenation tank.
The method for improving the efficiency of glucose hydrogenation according to the present invention is further illustrated below with reference to specific examples.
Example 1
The first embodiment of the method for improving the glucose hydrogenation efficiency comprises the following steps:
(11) feeding: the hydrogenation tank was charged with a catalyst mixture, 55% strength glucose solution at pH 6.2, and a feed volume of 6.8 cubic.
(12) Hydrogenation: and (3) heating the glucose solution in the step (11) for hydrogenation, controlling the pressure to be 7.5MPa, controlling the temperature to be 140 ℃ and controlling the temperature to be 136.5 ℃, and beginning to inject alkali at the speed of 4.4L/min for 17min, wherein the hydrogenation time is 210 min.
(13) Discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
Example 2
A second embodiment of the method of the present invention for increasing the efficiency of glucose hydrogenation comprises the steps of:
(21) feeding: the hydrogenation tank was charged with a catalyst mixture, 55% strength glucose solution at pH 6.2, and a feed volume of 6.8 cubic.
(22) Hydrogenation: and (3) heating the glucose solution in the step (21) for hydrogenation, controlling the pressure at 7.5MPa, controlling the temperature at 140 ℃ and controlling the temperature at 130 ℃, and starting to inject alkali at the speed of 4.4L/min for 17min, wherein the hydrogenation time is 210 min.
(23) Discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
Comparative example 1
(D1) Feeding: the hydrogenation tank was charged with a catalyst mixture, 55% strength glucose solution at pH 6.2, and a feed volume of 6.8 cubic.
(D2) Hydrogenation: and (4) heating the glucose solution in the step (D1) for hydrogenation, controlling the pressure at 7.5MPa and the temperature at 140 ℃, not injecting alkali, and carrying out hydrogenation for 240 min.
(D3) Discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
The glucose-hydrogenated liquid finally prepared in example 1, example 2 and comparative example 1 was measured, and the conversion rate of the glucose-hydrogenated liquid, the sorbitol content and the mannitol content of the glucose-hydrogenated liquid were evaluated, respectively, to obtain the following data tables. To enhance the comparability of the data, the alkali added in the alkali injection step of the above example is NaOH solution.
Reaction conditions Conversion (%) Sorbitol content (%) Mannitol content (%)
Injecting alkali at 136 DEG C 99.82 94.43 0.71
Injecting alkali at 130 DEG C 99.91 94.02 0.92
No need of alkali injection 99.52 93.78 0.98
From the comparison, the hydrogenation time after alkali injection is shortened by 30min, the conversion rate and the content are both higher than those of the hydrogenation without alkali injection, and the hydrogenation efficiency and the productivity after accounting can be improved by about 25-30%. Wherein, under the condition that the alkali injection temperature is 136.5 ℃, the conversion rate exceeds 99.8 percent, and simultaneously the sorbitol content can reach more than 94.4 percent, so the alkali injection effect is better at 136.5 ℃.
Example 3
A third embodiment of the method of improving the efficiency of glucose hydrogenation of the present invention comprises the steps of:
(31) feeding: the hydrogenation tank was charged with a catalyst mixture, 55% strength glucose solution at pH 6.2, and a feed volume of 6.8 cubic.
(32) Hydrogenation: and (3) heating and hydrogenating the glucose solution in the step (31), wherein the pressure is controlled to be 7.5MPa, the temperature is controlled to be 140 ℃, alkali is injected when the temperature is 136.5 ℃, the alkali injection speed is respectively 2.3L/min, 2.9L/min and 3.2L/min, the alkali injection time is 17min, and the hydrogenation time is 210 min.
(33) Discharging: and respectively finishing the glucose liquid at different alkali injection speeds in the subsequent process and then discharging to obtain the glucose hydrogenated liquid at different alkali injection speeds.
The glucose hydrogenation solution finally prepared at different alkali injection speeds was measured, and the conversion rate of the glucose hydrogenation solution, the sorbitol content and the mannitol content in the glucose hydrogenation solution were evaluated, respectively, to obtain the following data. To enhance the comparability of the data, the alkali added in the alkali injection process of this example is also NaOH solution.
Rate of injection of alkali pH after alkali injection Conversion (%) Sorbitol content (%) Mannitol content (%)
2.3L/min 6.8 99.84 94.60 0.56
2.9L/min 7.0 99.89 94.43 0.71
3.2L/min 7.5 99.87 93.83 0.96
From the comparison, under the same hydrogenation time, the alkali injection speed is respectively 2.3L/min, 2.9L/min and 3.2L/min, the conversion rate is more than 99.8 percent, but the higher the alkali injection speed is, the lower the sorbitol content is, the higher the mannitol content is, and the better the effect is under the alkali injection speed of 2.3L/min.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (8)

1. A method for increasing the efficiency of glucose hydrogenation comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55 +/-1% and the pH of 6.2 +/-0.2 into a hydrogenation tank;
step two, hydrogenation: heating and hydrogenating the glucose solution in the first step, controlling the pressure to be 6.5-10.5 MPa, controlling the temperature to be 110-140 ℃, starting to inject alkali at the speed of 2-5L/min when the temperature is 130-140 ℃, controlling the pH to be 6.6-7.5 after the alkali is injected, and controlling the whole hydrogenation time to be 200-230 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
2. The method of claim 1, wherein the catalyst mixture comprises a nickel-aluminum alloy and a low-concentration sorbitol solution, wherein the proportion of the nickel-aluminum alloy is 50%.
3. The method for improving the hydrogenation efficiency of glucose according to claim 1, wherein the alkali injection is any one of a NaOH solution, a KOH solution, a sodium carbonate solution, a sodium bicarbonate solution and a magnesium hydroxide solution added to the hydrogenation tank.
4. The method for increasing the efficiency of glucose hydrogenation according to claim 1, 2 or 3, comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55% and the pH value of 6.2 into a hydrogenation tank;
step two, hydrogenation: heating the glucose solution in the first step for hydrogenation, controlling the pressure to be 7.5MPa, the temperature to be 140 ℃ and the temperature to be 136.5 ℃, starting to inject alkali at the speed of 2.3L/min, controlling the pH to be 6.8 after alkali injection, and controlling the whole hydrogenation time to be 210 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
5. The method for increasing the efficiency of glucose hydrogenation according to claim 1, 2 or 3, comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55% and the pH value of 6.2 into a hydrogenation tank;
step two, hydrogenation: heating the glucose solution in the first step for hydrogenation, controlling the pressure to be 7.5MPa, the temperature to be 140 ℃ and the temperature to be 136.5 ℃, starting to inject alkali at the speed of 4.4L/min, controlling the pH to be 7.5 after alkali injection, and controlling the whole hydrogenation time to be 210 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
6. The method for increasing the efficiency of glucose hydrogenation according to claim 1, 2 or 3, comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55% and the pH value of 6.2 into a hydrogenation tank;
step two, hydrogenation: heating the glucose solution in the first step for hydrogenation, controlling the pressure to be 7.5MPa, controlling the temperature to be 140 ℃, starting to inject alkali at the speed of 4.4L/min when the temperature is 130 ℃, controlling the pH to be 7.5 after alkali injection, and controlling the whole hydrogenation time to be 210 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
7. The method for increasing the efficiency of glucose hydrogenation according to claim 1, 2 or 3, comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55% and the pH value of 6.2 into a hydrogenation tank;
step two, hydrogenation: heating the glucose solution in the first step for hydrogenation, controlling the pressure to be 7.5MPa, the temperature to be 140 ℃ and the temperature to be 136.5 ℃, starting to inject alkali at the speed of 2.9L/min, controlling the pH to be 7.0 after alkali injection, and controlling the whole hydrogenation time to be 210 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
8. The method for increasing the efficiency of glucose hydrogenation according to claim 1, 2 or 3, comprising the steps of:
step one, feeding: adding a catalyst mixed solution and a glucose solution with the concentration of 55% and the pH value of 6.2 into a hydrogenation tank;
step two, hydrogenation: heating the glucose solution in the first step for hydrogenation, controlling the pressure to be 7.5MPa, the temperature to be 140 ℃ and the temperature to be 136.5 ℃, starting to inject alkali at the speed of 3.2L/min, controlling the pH to be 7.5 after alkali injection, and controlling the whole hydrogenation time to be 210 min;
step three, discharging: and discharging after the subsequent process is finished to obtain the glucose hydrogenation solution.
CN201911209155.5A 2019-11-30 2019-11-30 Method for improving glucose hydrogenation efficiency Pending CN110845303A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114989230A (en) * 2022-06-20 2022-09-02 浙江华康药业股份有限公司 Method for preparing maltitol

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Cited By (1)

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Publication number Priority date Publication date Assignee Title
CN114989230A (en) * 2022-06-20 2022-09-02 浙江华康药业股份有限公司 Method for preparing maltitol

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