Method for preparing furaldehyde from steam exploded stalk rinse solution catalyzed by using solid acid with added polymerization inhibitor

Abstract

The invention discloses a method for preparing furaldehyde from a steam exploded stalk rinse solution catalyzed by using solid acid with an added polymerization inhibitor. The invention belongs to the technical field of bio-based chemical preparation. According to the invention, solid acid is used for replacing traditional strong acid in catalyzing pentose in steam exploded stalk rinse solution to subject to a cyclodehydration reaction, such that furaldehyde is prepared. During the reaction process, the polymerization inhibitor is added, such that side-reactions are inhibited. With modifications of the conditions, a maximum yield of furaldehyde reaches 37.5%, which is 68.1% of a theoretic yield. After the reaction, the solid catalyst can be repeatedly used, and can be reclaimed after high-temperature treatment. With the method, fractionated high-value utilization of three components of the stalks is realized. The solid acid is easy to be separated from a product, and can be reclaimed and reused, such that equipment corrosion can be avoided, and three-waste discharging can be reduced. With the added polymerization inhibitor, furaldehyde yield can be substantially improved. With the method for preparing furaldehyde from steam exploded stalk rinse solution catalyzed by using solid acid with added polymerization inhibitor, clean and high-efficiency conversion of the stalks is realized, such that a development trend of current green industries is satisfied. Therefore, the method has wide application prospect.

Description

technical field

[0001] The invention belongs to the technical field of preparation of bio-based chemicals, and in particular relates to a method for preparing furfural from water-washed stalks catalyzed by steam explosion with solid acid added with a polymerization inhibitor. Background technique

[0002] The energy and chemical industries of all countries in the world are highly dependent on fossil resources such as petroleum and coal. With the rapid development of economy, resource shortage, energy depletion and environmental pollution have become difficult problems for all countries. China is a large agricultural country with abundant plant biomass resources. The annual output of crop straw alone reaches 700 million tons, but nearly half of it is directly burned or discarded, which causes waste of resources and aggravates environmental pollution. Crop straw is mainly composed of cellulose, lignin and hemicellulose, and is renewable. Using crop straw resources as a platfor...

Examples

Embodiment 1

[0018] Cut the corn stalks into small pieces and carry out steam explosion pretreatment at a pressure of 1.5 MPa and maintaining pressure for 5 minutes; after the steam explosion is completed, add 300ml and immerse in water at 70°C for 10 minutes to extract the steam-exploded straw; after filtering and centrifuging the washing liquid, collect the supernatant, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml of steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 2% solid acid catalyst HZSM-5, and add 0.5% tert-butyl-phthalate Diphenol polymerization inhibitor; under stirring, the reactor is heated from room temperature to 170° C.; after reaching the temperature, adjust the opening size of the extraction valve to control the output flow of the distillate at 3ml / min. The yield of furfural was 22.3%.

Embodiment 2

[0020] Cut the rice straw into small pieces and carry out steam explosion pretreatment at a pressure of 1.5 MPa and maintain pressure for 5 minutes; after the steam explosion is completed, add 400ml and immerse in water at 60°C to extract the steam-exploded straw for 12 minutes; collect the supernatant after filtering and centrifuging the washing liquid, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 10% solid acid catalyst HZSM-5, and add 1% tert-butyl o-phthalate Diphenol polymerization inhibitor; Under stirring, reaction kettle is heated from room temperature to 180 ℃; After reaching the temperature, adjust the size of extraction valve opening to control the output flow rate of distillate 2.5ml / min; furfural yield is 12.8%.

Embodiment 3

[0022] Cut the wheat straw into small pieces and carry out steam explosion pretreatment at a pressure of 1.2MPa and maintain the pressure for 7 minutes; after the steam explosion is completed, add 500ml and immerse in water at 80°C to extract the steam-exploded straw for 10 minutes; the washing liquid is filtered and centrifuged to collect the supernatant, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 6% solid acid catalyst HZSM-5, and add 1.5% tert-butyl o-phthalate Diphenol polymerization inhibitor; under stirring, the reactor is heated from room temperature to 160° C.; after reaching the temperature, adjust the opening size of the extraction valve to control the output flow rate of the distillate to 3.5ml / min. The yield of furfural was 18.8%.

technical field

[0001] The invention belongs to the technical field of preparation of bio-based chemicals, and in particular relates to a method for preparing furfural from water-washed stalks catalyzed by steam explosion with solid acid added with a polymerization inhibitor. Background technique

[0002] The energy and chemical industries of all countries in the world are highly dependent on fossil resources such as petroleum and coal. With the rapid development of economy, resource shortage, energy depletion and environmental pollution have become difficult problems for all countries. China is a large agricultural country with abundant plant biomass resources. The annual output of crop straw alone reaches 700 million tons, but nearly half of it is directly burned or discarded, which causes waste of resources and aggravates environmental pollution. Crop straw is mainly composed of cellulose, lignin and hemicellulose, and is renewable. Using crop straw resources as a platfor...

Examples

Embodiment 1

[0018] Cut the corn stalks into small pieces and carry out steam explosion pretreatment at a pressure of 1.5 MPa and maintaining pressure for 5 minutes; after the steam explosion is completed, add 300ml and immerse in water at 70°C for 10 minutes to extract the steam-exploded straw; after filtering and centrifuging the washing liquid, collect the supernatant, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml of steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 2% solid acid catalyst HZSM-5, and add 0.5% tert-butyl-phthalate Diphenol polymerization inhibitor; under stirring, the reactor is heated from room temperature to 170° C.; after reaching the temperature, adjust the opening size of the extraction valve to control the output flow of the distillate at 3ml / min. The yield of furfural was 22.3%.

Embodiment 2

[0020] Cut the rice straw into small pieces and carry out steam explosion pretreatment at a pressure of 1.5 MPa and maintain pressure for 5 minutes; after the steam explosion is completed, add 400ml and immerse in water at 60°C to extract the steam-exploded straw for 12 minutes; collect the supernatant after filtering and centrifuging the washing liquid, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 10% solid acid catalyst HZSM-5, and add 1% tert-butyl o-phthalate Diphenol polymerization inhibitor; Under stirring, reaction kettle is heated from room temperature to 180 ℃; After reaching the temperature, adjust the size of extraction valve opening to control the output flow rate of distillate 2.5ml / min; furfural yield is 12.8%.

Embodiment 3

[0022] Cut the wheat straw into small pieces and carry out steam explosion pretreatment at a pressure of 1.2MPa and maintain the pressure for 7 minutes; after the steam explosion is completed, add 500ml and immerse in water at 80°C to extract the steam-exploded straw for 10 minutes; the washing liquid is filtered and centrifuged to collect the supernatant, Distill under reduced pressure and concentrate 3 to 6 times; take 100ml steam-exploded straw semi-fiber hydrolyzate with a sugar concentration of 61.4g / L, put it in a high-pressure reactor, add 6% solid acid catalyst HZSM-5, and add 1.5% tert-butyl o-phthalate Diphenol polymerization inhibitor; under stirring, the reactor is heated from room temperature to 160° C.; after reaching the temperature, adjust the opening size of the extraction valve to control the output flow rate of the distillate to 3.5ml / min. The yield of furfural was 18.8%.