CN103897717B - A kind of method utilizing Mierocrystalline cellulose preparing liquid fuel - Google Patents

Abstract

The present invention relates to a new method for producing liquid fuel from cellulose. In the method of the invention, cellulose is pretreated under high pressure under alkaline conditions, and then the obtained mixture is subjected to alkaline catalytic pyrolysis to prepare a mixture of liquid fuels such as acetone, isopropanol, butanol, butanone and ethanol. The method of the invention has the advantages of high selectivity, simple process, easy control, easy separation of the main product, and by-product liquid fuel, high utilization rate of organic matter, and high economic value and industrial application prospect.

Description

A method for producing liquid fuel from cellulose

technical field

The invention belongs to a new method for preparing liquid fuel by using cellulose, and the method is suitable for preparing liquid fuel by alkaline catalytic cracking of cellulose.

Background technique

Acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are important organic solvents and chemical raw materials, and are widely used in industries such as explosives, plastics, pharmaceuticals, organic glass, and synthetic rubber. Acetone is an important raw material for organic synthesis, used in the production of epoxy resin, polycarbonate, plexiglass, etc. It is also a good solvent, and is also used as a diluent, cleaning agent, and extraction agent. Isopropanol is an important chemical product and raw material used in pharmaceuticals, cosmetics, plastics, fragrances, paints, etc. Butanone is mainly used as a solvent, or as an intermediate in the preparation of medicines, dyes, detergents, spices, antioxidants and some catalysts. Butanol is a raw material for the manufacture of methyl ethyl ketone, synthetic flavors, dyes, etc., and is also used as a solvent. Butanol has a low vapor pressure and is less corrosive. It is a new generation of biofuel. Ethanol is a good organic solvent and disinfectant.

Before the early 1990s, the simultaneous production of acetone, butanol and ethanol was mainly based on grain fermentation. Since the 1990s, it was replaced by petrochemical methods. Now with the increasing depletion of petroleum resources and the increasing seriousness of environmental problems, the use of new methods to produce acetone, butanol and ethanol has attracted widespread attention from all over the world.

Chinese patent CN101161818A proposes a method for producing acetone-butanol by using wheat B starch instead of corn fermentation. Chinese patent CN101363031 proposes a production method of acetone butanol using corn bran as raw material through processes such as high-pressure cooking, enzymatic hydrolysis and saccharification. Chinese patent CN101358218A proposes a method for producing acetone-butanol by co-producing xylose from straw. The method utilizes xylose residue to be hydrolyzed into glucose under the action of cellulase, and uses glucose to ferment to produce acetone-butanol. Chinese patent CN102352381A proposes a chemical product acetone butanol, which uses xylose production waste liquid as raw material and utilizes microbial fermentation technology to biotransform sugar sources. Chinese patent CN102286549A proposes a method for producing acetone butanol by fermenting mixed sugars of cellobiose, xylose and glucose. Chinese patent CN102304550A proposes a method for producing ethanol or acetone-butanol using lignocellulose as a raw material. The lignocellulose is pretreated by a wet disc grinder-superfine particle melting machine physical method, and then fermented to produce ethanol or acetone butanol.

The above methods are all based on biological fermentation technology. The concentration of biological fermentation products is low, the energy required for enrichment and purification is very large, and the cycle of fermentation is very long, and the cycle of raw material pretreatment is also long. product production.

Therefore, it is necessary to research and develop a new method for producing liquid fuel by using readily available raw materials. The reaction cycle of this method should be short, and the product concentration is high and easy to separate and purify.

Contents of the invention

In order to overcome the problems in the prior art, the object of the present invention is to provide a new method for producing liquid fuel from cellulose, which has short reaction cycle, high product concentration and easy separation and purification.

Therefore, the present invention provides a method for producing liquid fuel from cellulose (hereinafter sometimes simply referred to as "the method of the present invention"), said method comprising the steps of: mixing a cellulose raw material with an excess of a basic catalyst (i.e., The molar ratio of the basic catalyst to the cellulose raw material is greater than 1) After mixing, add it to the tank reactor, perform pretreatment at a temperature of 100°C-250°C and a pressure of 0.1MPa-4.0MPa, and mix the pretreated mixture with excess The basic catalyst (that is, the molar ratio of the basic catalyst to the cellulose raw material in the mixture is greater than 1) is mixed and then added to the tubular reactor. 700°C, preferably at a temperature of 300°C to 700°C, heating and reacting for 0.1hr to 2hr, preferably 1h to 2h, and collecting the liquid product obtained from the reaction, the liquid product including liquid fuel.

In the method of the present invention, both the cellulose raw material and the basic catalyst can be added in solid form, for example, directly in the form of commercially available raw materials, or in the form of powder or granules after being processed by suitable crushing or grinding equipment. If charged in the form of powder or granules, the particle size is not limited, as long as it is convenient for charging to the reactor and mixing with each other.

In a preferred embodiment of the method of the present invention, the basic catalyst may be one or a mixture of any two oxides or hydroxides of alkali metals or alkaline earth metals.

In a preferred embodiment of the process according to the invention, the alkali metal may be sodium, preferably its hydroxide, ie sodium hydroxide, is used.

In a preferred embodiment of the method of the invention, the alkaline earth metal may be calcium, preferably its oxide, ie calcium oxide, is used.

In a further preferred embodiment of the process of the present invention, in case the basic catalyst is a mixture of calcium oxide and sodium hydroxide, the molar ratio of calcium oxide and sodium hydroxide may be 1:1 to 1:5.

In a preferred embodiment of the method of the present invention, the pretreatment time may be 1 hr to 10 hr.

In a preferred embodiment of the method of the present invention, the inert gas can be nitrogen or a mixed gas of nitrogen and water vapor (the ratio of the two is not limited, for example, a flow ratio of 1:1 can be used).

In the method of the present invention, the liquid fuel contained in the liquid product can be a mixture of products such as acetone, isopropanol, methyl ethyl ketone, butanol and ethanol, and the respective content ratio and distribution of each liquid fuel will vary according to operating conditions. Variety.

In the present invention, the pretreatment reactor can be a tank reactor, preferably an autoclave reactor, so that high-pressure and high-temperature pretreatment can be performed therein. And the use of reactor is not limited, can use the tubular reactor commonly used in this area, for example, vertical tubular reactor, as long as this reactor is suitable for collecting liquid product, and is suitable for catalyst and raw material to fully mix and get final product .

Beneficial effects of the present invention:

1. The method of the present invention has opened up a new path of producing liquid fuels such as acetone, isopropanol, methyl ethyl ketone, butanol and ethanol by catalytic cracking of cellulose.

2. The method of the present invention has high selectivity, simple process, easy control, easy separation of main product, and by-product liquid fuel, high utilization rate of organic matter, high economic value and industrial application prospect.

3. In the liquid product of the present invention, acetone, isopropanol, butanone and butanol are main products, and ethanol is produced simultaneously, and the selectivity of acetone, isopropanol, butanone and butanol is very high.

detailed description

The technical solutions and effects of the present invention are further described in detail through the following examples. Those skilled in the art should understand that the following examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

Example 1

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 500°C, react for 1hr, collect and react to obtain 10.7g of liquid, of which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.59g, 2.44g, 0.50g, 2.02g and 0.17 g.

Example 2

Mix 50g of cellulose with 20g of sodium hydroxide and 50g of water, place in an autoclave reactor, react at 170°C and 0.8MPa for 3hrs, mix the resulting mixture with 20g of calcium oxide, and place in a tubular reactor In the process, the mixed gas of nitrogen and water vapor (flow ratio is 1:1) is the reaction atmosphere, heated to 500 ° C, reacted for 1 hr, collected and reacted to obtain 9.3 g of liquid, wherein acetone, isopropanol, methyl ethyl ketone, butanol and ethanol 2.00g, 0.52g, 1.71g, 0.42g and 0.16g respectively.

Example 3

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of sodium hydroxide, and place in a tubular reactor In the process, the mixed gas of nitrogen and water vapor (flow ratio is 1:1) is the reaction atmosphere, heated to 500 ° C, reacted for 1 hr, collected and reacted to obtain 1.5 g of liquid, wherein acetone, isopropanol, methyl ethyl ketone, butanol and ethanol 0.27g, 0.08g, 0.25g, 0.09g and 0.04g respectively.

Example 4

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , passing water vapor as the reaction atmosphere, heated to 500 ° C, reacted for 1 hr, collected and reacted to obtain 11.0 g of liquid, of which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol were 2.47 g, 0.66 g, 2.07 g, 0.57 g and 0.20g.

Example 5

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 140°C, react for 2 hours, collect and react to obtain 0.4g of liquid, in which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.02g, 0.05g, 0.02g, 0.05g and 0.01 g.

Example 6

Mix 50g of cellulose with 20g of sodium hydroxide and 50g of water, place in an autoclave reactor, react at 170°C and 0.8MPa for 3hrs, mix the resulting mixture with 20g of calcium oxide, and place in a tubular reactor In the process, nitrogen was used as the reaction atmosphere, heated to 700°C, reacted for 2 hours, and collected and reacted to obtain 12.1g of liquid, of which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol were respectively 0.67g, 2.49g, 0.57g, 2.59g and 0.25g.

Example 7

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 200°C, react for 0.1hr, collect and react to obtain 0.1g of liquid, in which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.01g, 0.02g, 0.01g, 0.02g and trace.

Example 8

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 170°C and 0.8MPa for 3 hours, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 700°C, react for 0.1hr, collect and react to obtain 9.0g of liquid, in which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.51g, 2.00g, 0.47g, 1.94g and 0.13g.

Example 9

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 100°C and 0.1MPa for 3 hours, mix the resulting mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 300°C, react for 1hr, collect and react to obtain 1.2g of liquid, in which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.06g, 0.20g, 0.05g, 0.20g and 0.01 g.

Example 10

Mix 50g of cellulose with 20g of calcium oxide and 50g of water evenly, place in an autoclave reactor, react at 250°C and 4.0MPa for 3hrs, mix the obtained mixture with 20g of calcium oxide, and place in a tubular reactor , pass nitrogen gas as the reaction atmosphere, heat to 500°C, react for 1hr, collect and react to obtain 13.4g of liquid, in which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.60g, 1.80g, 0.50g, 1.71g and 0.11 g.

Example 11

Mix 50g of cellulose with 20g of calcium oxide, 20g of sodium hydroxide, and 50g of water, place in an autoclave reactor, and react for 1 hour at 100°C, 0.1MPa, mix the obtained mixture with 20g of calcium oxide, place in In the tubular reactor, nitrogen gas is used as the reaction atmosphere, heated to 300°C, reacted for 1 hour, and collected and reacted to obtain 1.2g of liquid, of which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.05g, 0.21g, and 0.07g , 0.22g and 0.02g.

Example 12

Mix 50g of cellulose with 20g of calcium oxide, 20g of sodium hydroxide, and 50g of water, place in an autoclave reactor, and react at 250°C and 0.1MPa for 10 hours, mix the obtained mixture with 20g of calcium oxide, place in In the tubular reactor, nitrogen gas is used as the reaction atmosphere, heated to 300 ° C, reacted for 1 hour, and collected and reacted to obtain 12.7 g of liquid, of which acetone, isopropanol, methyl ethyl ketone, butanol and ethanol are respectively 0.79 g, 2.67 g, and 0.53 g , 2.32g and 0.19g.

Claims (10)

1. utilize a method for Mierocrystalline cellulose preparing liquid fuel, said method comprising the steps of: add tank reactor after being mixed with excessive basic catalyst by Mierocrystalline cellulose, wherein excessive basic catalyst and cellulosic mol ratio are greater than 1; Pre-treatment is carried out under the pressure of the temperature of 100 DEG C-250 DEG C and 0.1MPa-4.0MPa, mixture pre-treatment obtained adds tubular reactor after mixing with excessive described basic catalyst further, and the cellulosic mol ratio in the mixture that wherein excessive described basic catalyst and pre-treatment obtain is greater than 1; Under the atmosphere of rare gas element, water vapour or both mixed gass and at the heating temperatures of 140 DEG C-700 DEG C, react 0.1hr ~ 2hr, collect the product liquid be obtained by reacting, described product liquid comprises liquid fuel.

2. method according to claim 1, is characterized in that described basic catalyst is selected from the mixture of a kind of in the oxide compound of basic metal or alkaline-earth metal or oxyhydroxide or any two kinds.

3. method according to claim 2, is characterized in that described basic metal is sodium.

4. method according to claim 2, is characterized in that described alkaline-earth metal is calcium.

5. method according to claim 1, is characterized in that described basic catalyst is the mixture of calcium oxide and sodium hydroxide.

6. method according to claim 5, is characterized in that the mol ratio of calcium oxide and sodium hydroxide is 1:1 ~ 1:5.

7. the method according to any one of claim 1-6, is characterized in that the described pretreated time is 1hr ~ 10hr.

8. the method according to any one of claim 1-6, is characterized in that described rare gas element is nitrogen.

9. the method according to any one of claim 1-6, is characterized in that temperature of reaction is 300 DEG C ~ 700 DEG C.

10. the method according to any one of claim 1-6, is characterized in that described liquid fuel is the mixture of acetone, Virahol, butanols, butanone and ethanol.