Method of preparing xylitol from crop straws

[0017] Example 1:

[0018] A method for preparing xylitol from crop straws includes:

[0019] (1) Steam and explode the crop stalks. The specific conditions for the treatment are: add the stalks cut into 2-3 cm into the steam explosion machine, then pass in water vapor, keep it under a pressure of 2Mpa for 15 minutes, and then quickly release the pressure To normal pressure, get steamed straw;

[0020] (2) The crop straws after the steaming and explosion treatment are boiled to obtain boiled liquid; the boiled temperature is 90 ℃, and the boiled time is 1 hour;

[0021] (3) Use microwave-assisted acid hydrolysis to process the boiled liquid to obtain a hydrolysate; wherein the microwave power is 700 W, the reaction is at 90°C for 10 hours, and the acid used is sulfuric acid with a concentration of 0.6 mol / L;

[0022] (4) Neutralize the hydrolyzed solution with 10% NaOH by mass fraction until it is neutral, and then use D301 resin and 732 resin to purify the neutralized solution to obtai

[0024] Example 2

[0025] A method for preparing xylitol from crop straws includes:

[0026] (1) The crop stalks are steamed and exploded, and the specific conditions are as follows: add the stalks cut into 2-3 cm into the steamer, then pass in water vapor, keep it under a pressure of 4Mpa for 20 minutes, and then quickly release the pressure To normal pressure, get steamed straw;

[0027] (2) The crop straws after the steaming and explosion treatment are boiled to obtain boiled liquid; the boiled temperature is 95 ℃, and the boiled time is 1 hour;

[0028] (3) Use microwave-assisted acid hydrolysis to process the boiled liquid to obtain a hydrolysate; wherein the microwave power is 700 W, the reaction is at 95°C for 20 hours, and the acid used is sulfuric acid with a concentration of 1 mol / L;

[0029] (4) Neutralize the hydrolyzed solution with 15% NaOH with a mass fraction of 15% until it is neutral, and then use D301 resin and 732 resin to purify the neutralized solution to obtain a

[0031] Example 3

[0032] A method for preparing xylitol from crop straws includes:

[0033] (1) Steam and explode crop stalks. The specific conditions for the treatment are: add the stalks cut into 2-3 cm into the steam explosion machine, and then pass in water vapor, keep it under a pressure of 3Mpa for 15 minutes, and then quickly release the pressure To normal pressure, get steamed straw;

[0034] (2) The crop straws after the steaming and explosion treatment are boiled to obtain boiled liquid; the boiled temperature is 90 ℃, and the boiled time is 1 hour;

[0035] (3) Use microwave-assisted acid hydrolysis to process the boiled liquid to obtain a hydrolysate; among them, the microwave power is 700 W, the reaction is at 93°C for 15 hours, and the acid used is sulfuric acid with a concentration of 0.8 mol / L;

[0036] (4) Neutralize the hydrolyzed solution with 15% NaOH with a mass fraction of 15% until it is neutral, and then use D301 resin and 732 resin to purify the neutralized sol