WO2010016462A1 - Methods for producing glycol from glycerin and 1-propanol - Google Patents

Abstract

Provided are a glycol production method from glycerin that is characterized by reacting glycerin under atmospheric pressure or increased pressure in the presence of hydrogen by using a copper-containing catalyst and a 1-propanol production method that includes said production method as one step.

Description

Process for producing glycol and 1-propanol from glycerin

The present invention relates to a method for producing glycol, a method for producing glycol by using glycerol having an adjacent hydroxyl group as a raw material and using a catalyst mainly composed of copper and reacting in the presence of hydrogen under atmospheric pressure or under pressure. About. The present invention also relates to a method for producing 1-propanol comprising the method for producing the glycol as one step.

Glycols typified by propylene glycol are very important substances in the chemical industry, used as polyester raw materials, organic solvents, reaction intermediates, and the like. The current industrial production method of propylene glycol is mainly performed by hydration of propylene oxide. However, propylene, which is a raw material for propylene oxide, is a compound derived from a fossil resource using naphtha as a main raw material, and cannot be said to be a manufacturing method that responds to environmental problems that require recent global warming countermeasures.

In recent years, a method for producing acetol (hydroxyacetone) by dehydration reaction of glycerin (Patent Document 1) and a method for producing glycol via acetol (Patent Document 2) have been disclosed. Is not efficient industrially. On the other hand, a method for producing propylene glycol directly from glycerin in the presence of a catalyst and hydrogen has already been reported (Non-Patent Document 1). However, this method has a high reaction pressure, and the reaction apparatus is a pressure apparatus. Since it was necessary, there was a problem that the capital investment increased industrially. Similarly, although a method of directly synthesizing propylene glycol from glycerin in the presence of hydrogen is disclosed (Patent Documents 3 and 4), it is carried out under a relatively high pressure and is not industrially preferable, and further propylene glycol. The selectivity is not satisfactory. On the other hand, although the method of performing reaction under atmospheric pressure is also disclosed (Non-patent Document 2), the selectivity of propylene glycol is similarly not surprising.

On the other hand, 1-propanol is used as an organic solvent, an ester raw material, a chemical intermediate, a pharmaceutical intermediate production solvent, and the like, and is an important substance in the chemical industry. It was not found. Conventionally, 1-propanol is generally obtained by hydrogenation of propionaldehyde by a hydroformylation reaction of ethylene (Non-patent Document 3) or by hydrogenation of allyl alcohol obtained from the reaction of acetic acid and propylene. (Patent Document 5). However, the hydroformylation reactor is a pressure reactor and requires a large capital investment for its construction. Acetic acid, which is the raw material for allyl alcohol, is highly corrosive to the equipment, and this is also very large for facilities with corrosion resistance. There was a problem that investment was necessary. Furthermore, since the raw materials used in these production methods are made from petroleum, which is a fossil resource, the final form of the product is carbon dioxide, which is one of the factors affecting the global climate change, which has become a particular problem in recent years.

In this regard, BDF (Bio Diesel Fuel), which has been attracting attention as a renewable energy in recent years, is produced by transesterifying animal and vegetable oils, which are fats and oils, to methyl ester (FAME) using methanol and a catalyst. Is a by-product. At present, no definitive means for effectively using the by-product glycerin has been found, and this is a very big problem from the viewpoint of effective use of resources, and a method for effectively using the glycerin is required.

JP-A-5-255157 US Pat. No. 5,426,249 International Publication No. 2007/053705 Pamphlet JP 2007-283175 A Japanese Patent No. 2663965

The first problem of the present invention is to solve the above-mentioned conventional technical problem, and to provide a method for producing glycol from glycerin with high selectivity at atmospheric pressure or under pressure. A second object of the present invention is to provide a method for producing 1-propanol with high efficiency as a method for recycling glycerol.

As a result of intensive studies, the present inventors have studied a reaction condition in detail using a catalyst mainly composed of copper, thereby producing a method for producing glycol from glycerin with high selectivity even under atmospheric pressure or under pressure. As a result, the present invention has been completed.
In addition, the present inventors use a heteropolyacid or a heteropolyacid and a catalyst carrier complex as a catalyst for a glycol produced from glycerin, such as 1,2-propanediol, and the adsorbing reaction is caused by a dehydration reaction of 1,2-propanediol. It was found that the secondary hydroxyl group of the hydroxyl group having a hydroxyl group to be selectively dehydrated to form an enol form forms a carbonyl form (lower saturated aldehyde) by tautomerism in the reaction system.
As a result of intensive studies based on such knowledge, the present inventors set the method for producing glycol, specifically 1,2-propanediol from glycerin as the first step, and in the first step, A process for producing 1-propanol comprising a second step of converting the produced 1,2-propanediol into propanal and a third step of converting the propanal into 1-propanol, It came to be completed.

The glycol production method of the present invention is defined by the following items (1) to (13).
(1) A method for producing glycol from glycerin, characterized by using a catalyst containing copper as a component and reacting under atmospheric pressure or under pressure in the presence of hydrogen.

(2) The production method according to (1), wherein the reaction is performed under atmospheric pressure.

(3) The production method according to (2), wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 150 to 500.

(4) The production method according to (2), wherein the ratio of the number of moles of hydrogen supplied into the reactor to the number of moles of raw material supplied into the reactor is 150 to 400.

(5) The production method according to (2), wherein the ratio of the number of moles of hydrogen supplied into the reactor to the number of moles of raw material supplied into the reactor is 150 to 300.

(6) The production method according to (1), wherein the reaction is performed under pressure.

(7) The production method according to (6), wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 20 to 30.

(8) The first stage reaction in which glycerin is dehydrated and acetol is generated is performed at 150 to 260 ° C., and the second stage reaction in which hydrogen is added to the generated acetol to generate glycol is performed at 100 to 220 ° C. The manufacturing method according to any one of (1) to (7), wherein:

(9) The production method according to (8), wherein the first stage reaction is performed at 150 to 225 ° C., and the second stage reaction is performed at 120 to 175 ° C.

(10) The production method according to (8), wherein the first stage reaction is performed at 150 to 200 ° C., and the second stage reaction is performed at 120 to 160 ° C.

(11) The production method according to (8), wherein the first stage reaction is performed at 230 to 260 ° C., and the second stage reaction is performed at 150 to 220 ° C.

(12) The production method according to (8), wherein the first-stage reaction is performed at 240 to 250 ° C., and the second-stage reaction is performed at 150 to 175 ° C.

(13) The production method according to any one of (1) to (12), wherein the glycol is 1,2-propylene glycol.

(14) First step of converting glycerin to 1,2-propylene glycol using the production method described in (13), and conversion of 1,2-propylene glycol produced in the first step to propanal And a third step of converting the propanal produced in the second step to 1-propanol.

(15) The production method according to (14), wherein the second step is performed using a catalyst comprising a heteropolyacid or a heteropolyacid-catalyst support complex.

(16) The production method according to (15), wherein the heteropolyacid or the heteropolyacid of the heteropolyacid-catalyst support complex includes any one selected from silicotungstic acid, silicomolybdic acid, phosphotungstic acid, and phosphomolybdic acid.

(17) The production method according to (15), wherein the heteropolyacid or the heteropolyacid of the heteropolyacid-catalyst support complex is silicotungstic acid.

(18) The third step is performed using a hydrogenation catalyst containing at least one catalyst component selected from copper, platinum, nickel, palladium and ruthenium (14) to (17) The manufacturing method in any one of.

(19) The third step is performed using a hydrogenation catalyst containing any one or more kinds of catalyst components selected from copper, nickel, and palladium. The manufacturing method in any one.

The present invention provides a method for producing glycol from glycerin with high selectivity at atmospheric pressure or under pressure. In addition, the method for producing 1-propanol of the present invention provides a method for effectively utilizing glycerin. Furthermore, according to the method for producing 1-propanol of the present invention, 1-propanol can be obtained from glycerin with high efficiency.

The glycol production method of the present invention is a method for producing glycol using glycerin as a raw material. Examples of glycols produced from glycerin include 1,2-propylene glycol and 1,3-propylene glycol. In the present invention, 1,2-propylene glycol (hereinafter also referred to as 1,2-propanediol) is preferable. To be manufactured.

The glycol production method of the present invention is characterized by being carried out under atmospheric pressure or under pressure. Production of glycol using glycerin as a raw material is carried out under a somewhat high pressure (2 to 28 MPa). It is known that if the pressure is too low, the conversion rate of glycerin is lowered and the selectivity of glycol is lowered. (For example, described in Patent Document 4). The production method of the present invention can maintain a high glycol selectivity by setting specific reaction conditions under atmospheric pressure or under pressure set to a pressure lower than the pressure described in the above document. is there.

The atmospheric pressure in the present invention refers to about 1 atmosphere (about 0.1 MPa), but is not limited to the condition of strictly 1 atmosphere, and the range of atmospheric pressure and the range understood by those skilled in the art are within the scope of the present invention. It is the range of atmospheric pressure.
On the other hand, under pressure in the present invention means 0.2 to 0.4 MPa, and among these, pressure under pressure particularly suitable for the reaction includes 0.3 MPa.

The glycol production method of the present invention is characterized by reacting in the presence of hydrogen. The presence of hydrogen in the glycol production method of the present invention means that hydrogen is present when glycerin as a raw material comes into contact with the catalyst. Therefore, the raw material glycerin and hydrogen can be mixed and then supplied to the reactor, and if the raw material glycerin and hydrogen are present when they are in contact with the catalyst, they are separately supplied to the device. You can also. In the present invention, when the reaction is carried out under atmospheric pressure, it is preferable to supply a relatively large amount of hydrogen from the viewpoint of improving the selectivity. On the other hand, when the reaction is performed under pressure, a high selectivity can be obtained even with a small amount of hydrogen supply.

In the glycol production method of the present invention, when the reaction is carried out under atmospheric pressure, the ratio of the number of moles of hydrogen fed into the reactor to the number of moles of raw material fed into the reactor is from 150. A range of 500 is preferred. A more preferred molar ratio range is from 150 to 400, and even more preferably from 150 to 300. When the hydrogen supply amount in the present invention satisfies the above range, glycol can be produced with higher selectivity.
On the other hand, in the glycol production method of the present invention, when the reaction is carried out under pressure, the ratio of the number of moles of hydrogen fed into the reactor to the number of moles of raw material fed into the reactor is 20 A range of from 30 to 30 is preferred. When the hydrogen supply amount in the present invention satisfies the above range, glycol can be produced with good selectivity, the catalyst life is extended, and more economically preferable.

The hydrogen supply amount in the glycol production method of the present invention is such that, when the reaction is carried out under atmospheric pressure, the hydrogen flow rate for a catalyst volume of 1 ml is 30 to 150 ml / min. It is preferable that More preferably 40 to 120 ml / min. And more preferably 50 to 90 ml / min. It is. When the hydrogen supply amount in the present invention satisfies the above range, glycol can be produced with higher selectivity, which is economically preferable. On the other hand, the hydrogen supply amount in the glycol production method of the present invention is preferably such that, when the reaction is carried out under pressure, the hydrogen flow rate is 0.010 to 0.080 L / min with respect to 1 mL of the catalyst volume. It is particularly preferred that it is ˜0.065 L / min.

The glycol production method of the present invention is characterized by using a catalyst containing copper as a component. The catalyst containing copper as a component used in the present invention is a commercially available product, a product obtained by reducing a commercially available product, a product obtained by pyrolyzing copper oxide, hydroxide, carbonate, nitrate, acetate, or the like, or known after pyrolysis. Any form such as those reduced by the above method can be used as a catalyst.

Further, the catalyst carrier in the catalyst containing copper as a component used in the glycol production method of the present invention is not particularly limited, but aluminum oxide, chromium oxide, zirconium oxide, silicon dioxide, etc. are used alone or in combination with each oxide. It is preferably used as a composite oxide. In addition, the copper component can be supported on the catalyst carrier by a known method such as impregnation or coprecipitation.

As a catalyst containing copper as a component used in the glycol production method of the present invention, a copper-aluminum oxide catalyst, a copper-chromium oxide catalyst, a copper-zirconium oxide catalyst, a copper-silicon dioxide catalyst, a copper-aluminum oxide-zirconium oxide catalyst And a copper-aluminum oxide-chromium oxide catalyst. Among these, it is particularly preferable to use a copper-aluminum oxide catalyst, a copper-chromium oxide catalyst, or a copper-aluminum oxide-zirconium oxide catalyst.

The reaction apparatus used in the glycol production method of the present invention is an apparatus capable of causing the reaction to proceed by bringing glycerol and hydrogen as raw materials into contact with the catalyst when the reaction is performed under atmospheric pressure. There is no particular limitation. For example, an apparatus in which a predetermined amount of catalyst precursor is placed in a gas phase flow reaction apparatus and reduced by a known method to form an active catalyst layer in the gas phase flow reaction apparatus can be exemplified. It is possible to produce glycol by supplying glycerin and hydrogen as raw materials to such an apparatus and reacting them.
On the other hand, in the reactor used in the glycol production method of the present invention, when the reaction is carried out under pressure, for example, a gas-phase flow reaction device in which the catalyst layer is formed is used as a pressure circulation blower. A fixed-bed pressurized gas-phase flow reaction apparatus in which a pressurizing means is provided and the pressure in the apparatus can be adjusted can be used.

In the glycol production method of the present invention, the first-stage reaction in which glycerin is dehydrated to produce acetol is carried out at 150 to 260 ° C., preferably 150 to 250 ° C., and hydrogen is added to the produced acetol to produce glycol. The second stage reaction is preferably carried out at 100 to 220 ° C, preferably 100 to 190 ° C.

In the case of the gas phase flow reaction apparatus as described above, a catalyst layer is formed in the apparatus, but the reaction temperature is set in the above range so that the reaction proceeds at two different temperatures in the upper layer part and the lower layer part of the catalyst layer. It is preferable to control. This is because the reaction in which glycol is generated from glycerin is a two-stage reaction, and there is a temperature at which each reaction easily proceeds.

The reaction temperature in the present invention can be measured, for example, by directly measuring the temperature of the catalyst in the case of the reaction apparatus having the catalyst layer as described above. In the case of a device in which the raw material passes through the catalyst downward, the first stage reaction is performed at the upper part of the catalyst layer as described above, and the reaction temperature of the first stage reaction is measured by measuring the surface temperature of the upper part of the catalyst layer. Can be measured. In addition, the second stage reaction is performed at the lower part of the catalyst layer as described above, and the reaction temperature of the second stage reaction can be measured by measuring the surface temperature of the lower part of the catalyst layer.

When the reaction is carried out at atmospheric pressure, the two reaction temperatures are more preferably that the first stage reaction is carried out at 150 to 225 ° C. and the second stage reaction is carried out at 120 to 175 ° C. More preferably, the first stage reaction is performed at 150 to 200 ° C., and the second stage reaction is performed at 120 to 160 ° C.
On the other hand, when the reaction is performed under pressure, it is more preferable that the first stage reaction is performed at 230 to 260 ° C., and the second stage reaction is performed at 150 to 220 ° C. More preferably, the reaction is performed at 240 to 250 ° C., and the second-stage reaction is performed at 150 to 175 ° C.
When the first-stage reaction temperature and the second-stage reaction temperature of the present invention satisfy the above ranges, the reaction is sufficiently advanced and glycol can be produced with good selectivity, which is economically preferable.

The above two reaction temperature regions preferably have a temperature difference. This is because there is a temperature suitable for each reaction. When the reaction is carried out under atmospheric pressure, it preferably has a temperature difference of 10 ° C. to 80 ° C., more preferably 20 ° C. to 40 ° C. When the reaction is carried out under pressure, it preferably has a temperature difference of 20 ° C. to 100 ° C., more preferably 30 ° C. to 90 ° C.

In the glycol production method of the present invention, when the reaction is carried out under pressure, the amount of the catalyst may be a catalyst amount that can be usually provided in the reaction apparatus, but the fixed bed pressurized gas phase flow reaction apparatus. in the case of the feed by weight glycerin per unit relative to the catalyst weight hourly (WHSV: weight Hourly Space Velocity; units, h ^-1) is represented by at WHSV values, in the range of 0.3h ^-1 0.05 In view of the life and yield of the catalyst, the WHSV value is preferably in the range of 0.1 to 0.3 h ⁻¹ , more preferably the WHSV value is 0.2 to 0.3 h ^−1. It is preferable that it is the range of these.

As a method for controlling the reaction temperature region, the temperature can be controlled by using an electric furnace, a hot air furnace, a heat medium furnace or the like.

In the glycol production method of the present invention, from the viewpoint of sufficiently reacting the raw materials, it is preferable that the contact time during which the raw glycol and hydrogen are in contact with the catalyst is 1 to 200 seconds. More preferably, it is 5 to 150 seconds.

The raw material glycerin may contain water, and the amount of water in the glycerin can be applied in an arbitrary range, preferably in the range of 0 to 98% by weight, and more preferably in the range of 20 to 80% by weight.

Next, the method for producing 1-propanol of the present invention will be described. The method for producing 1-propanol of the present invention includes the above-described method for producing glycol as a production step (first step) of 1,2-propanediol. Furthermore, the method for producing 1-propanol of the present invention comprises a second step of converting 1,2-propanediol produced in the first step to propanal, and conversion of the propanal to 1-propanol. And a third step.

The first step is a step of converting glycol to 1,2-propanediol using the glycol production method described above. In this step, the conditions used in the glycol production method described above can be used as they are.

The second step is a step of converting 1,2-propanediol produced in the first step into propanal. In this step, it is preferable to use a heteropolyacid or a heteropolyacid-catalyst support complex as a catalyst. Heteropoly acids are composed of heteroatoms such as silicon, phosphorus and arsenic and metal oxyacid skeletons such as tungsten, vanadium and molybdenum. A preferred example is silicotungstic acid, more preferred.

The heteropolyacid may be a free heteropolyacid, and may be used as a salt of the heteropolyacid by replacing some or all of the protons with other cations. Accordingly, the heteropolyacid referred to in the present invention includes salts of these heteropolyacids. Examples of cations that can be substituted with protons include ammonium, alkali metals, alkaline earth metals, and the like.

The heteropolyacid may be an anhydride or a crystal water-containing product, but the anhydride is preferred because the reaction is faster and the formation of by-products is suppressed. In the case of a crystal water-containing material, effects similar to those of the anhydride can be obtained by performing dehydration treatment such as drying under reduced pressure or azeotropic dehydration with a solvent in advance.

By using a heteropolyacid as a catalyst, both 1,2-propanediol conversion and propanal selectivity are higher than those of commonly used catalysts such as aluminum oxide, silicon dioxide, and silica-alumina. Numerical values are shown, and as a result, propanal can be produced in good yield. In particular, when silicotungstic acid is used as a catalyst, higher propanal selectivity is exhibited. Note that a plurality of heteropolyacids can be used as the catalyst.

The heteropolyacid-catalyst carrier complex is obtained by supporting the heteropolyacid on a catalyst carrier that is usually used as a catalyst carrier. Preferred examples of the catalyst carrier include aluminum oxide, silicon dioxide, activated carbon and the like. In the present invention, it is more preferable to use silicon dioxide as the catalyst support. A plurality of the above catalyst carriers can be used. In addition, since the heteropolyacid has a large molecular size, it is often used by being physically immobilized on a stable support. In the examples described later, the heteropolyacid is used as a heteropolyacid-catalyst support complex. The catalytic activity does not depend on the presence or absence of the catalyst carrier, and the same effect can be obtained even if the heteropolyacid is used without being supported on the carrier.

Specific examples of the heteropolyacid-catalyst support complex include silicotungstic acid-aluminum oxide complex, silicotungstic acid-silicon dioxide complex, silicotungstic acid-activated carbon complex, silicomolybdic acid-aluminum oxide complex, silicomolybdenum. Acid-silicon dioxide complex, silicomolybdic acid-activated carbon complex, phosphotungstic acid-aluminum oxide complex, phosphotungstic acid-silicon dioxide complex, phosphotungstic acid-activated carbon complex, phosphomolybdic acid-aluminum oxide complex, Examples thereof include a phosphomolybdic acid-silicon dioxide complex and a phosphomolybdic acid-activated carbon complex. Preferably, silicotungstic acid-aluminum oxide complex, silicotungstic acid-silicon dioxide complex, silicotungstic acid-activated carbon complex, silicomolybdic acid-silicon dioxide complex, phosphotungstic acid-silicon dioxide complex, phosphomolybdic acid A silicon dioxide composite, more preferably a silicotungstic acid-silicon dioxide composite.

The heteropolyacid can be used as a catalyst in any form such as a commercially available product or a compound prepared by a known method. Similarly, the above heteropolyacid-catalyst carrier complex can be used as a catalyst in any form, such as a commercially available product, a commercially available product of the heteropolyacid, or a product prepared by a known method supported on a catalyst carrier. Is possible.

As a method for supporting the heteropolyacid component on the catalyst carrier in the heteropolyacid-catalyst carrier complex, a known method such as an impregnation method or a coprecipitation method can be used. For example, a composite obtained by drying a solid obtained by impregnating silicon dioxide as a catalyst carrier component with a heteropolyacid such as silicotungstic acid can be used as the catalyst.

The content ratio of the heteropolyacid: catalyst support in the heteropolyacid-catalyst support complex is preferably 0.5: 99.5 to 50:50 by weight. When the heteropolyacid: catalyst content of the heteropolyacid in the catalyst support is 0.5 to 50, sufficient catalytic activity can be obtained, and the catalytic activity can be prevented from decreasing in a short time.

In the second step, 1,2-propanediol having an adjacent hydroxyl group is used as a catalyst for the heteropolyacid or heteropolyacid-catalyst support complex, so that only the secondary hydroxyl group of 1,2-propanediol is obtained. It is characterized in that propanal is produced by selective elimination and isomerization of the produced enol intermediate to a carbonyl form by tautomerism.

The 1,2-propanediol used in the second step may contain moisture. The water content in the raw material containing 1,2-propanediol is preferably in the range of 0 to 95% by weight, more preferably in the range of 0 to 70% by weight, and most preferably in the range of 0 to 30% by weight.

The reaction apparatus used in the second step is not particularly limited, but industrially, an apparatus capable of performing a gas phase flow reaction in which the raw material is gasified and passed through an appropriate catalyst layer is preferable. When using a gas-phase flow reaction apparatus, for example, a predetermined amount of catalyst is put into the gas-phase flow reaction apparatus and pretreated by a known method to form an active catalyst layer in the gas-phase flow reaction apparatus. Thus, it is possible to produce propanal by gasifying and supplying 1,2-propanediol.

The catalyst pretreatment can be performed by a known method that can activate the catalyst layer. For example, the catalyst layer is activated by heat treatment at 200 ° C. for about 1 hour in a nitrogen stream. Can be mentioned.

The reaction temperature in the second step is preferably a temperature range of 140 ° C. to 300 ° C., that is, a temperature at which 1,2-propanediol exists as a gas phase. In order to sufficiently advance the reaction, 140 ° C. or higher is preferable, and in order to keep the product selectivity favorable, 300 ° C. or lower is preferable. A more preferable temperature range is 160 ° C. to 240 ° C., and since the yield is higher, a range of 180 ° C. to 240 ° C. is further preferable, and a range of 200 ° C. to 220 ° C. is most preferable.

The amount of catalyst used in the second step and the reaction time of the step are represented by the feed weight of 1,2-propanediol per unit time relative to the catalyst weight (WHSV: Weight Hourly Space Velocity; unit, h ⁻¹ ). is, in WHSV value are available in the range of 20h ^-1 from 0.1, preferably WHSV value in terms of life and yield of the catalyst is in the range of 7h ^-1 from 0.5, more preferably Is the WHSV value, ranging from 1 to 6h ⁻¹ . As will be described later, when the production method of 1-propanol of the present invention is carried out in one reactor, the reaction time in the catalyst layer in the reactor in which this second step is carried out is within the above range. It is preferable to adjust the feed amount of the raw material and the supply amount of hydrogen in the first step.

The third step is a step of converting the propanal produced in the second step to 1-propanol, and a known method can be used for this step without any particular limitation. For example, the process using the hydrogenation catalyst containing any one or more types of catalyst components chosen from copper, platinum, nickel, palladium, and ruthenium as a catalyst can be used.
As a reaction apparatus for performing such a process, a known apparatus can be used without any particular limitation, and an apparatus capable of a gas phase flow reaction used in the second process is preferable. When using a gas-phase flow reactor, for example, a predetermined amount of a hydrogenation catalyst is placed in the gas-phase flow reactor and pretreated by a known method to form an active catalyst layer in the gas-phase flow reactor. Let Thereby, it is possible to produce 1-propanol by converting propanal.

As the hydrogenation catalyst, a catalyst containing at least one selected from copper, nickel and palladium as a component is preferably used. A specific example of a catalyst containing copper as a component is a commercial product, a product obtained by reducing a commercial product, a product obtained by thermally decomposing copper oxide, hydroxide, carbonate, nitrate, acetate, or the like, or Any form such as those reduced by a known method after thermal decomposition can be used as a catalyst.

Further, the catalyst carrier in the hydrogenation catalyst is not particularly limited, but aluminum oxide, chromium oxide, zirconium oxide, silicon dioxide, etc. are suitably used alone or as a composite oxide in which respective oxides are combined. In addition, a method for supporting a component such as copper on a catalyst carrier can be performed by a known method such as impregnation or coprecipitation.

Catalysts preferably used as the hydrogenation catalyst include copper-aluminum oxide catalyst, copper-chromium oxide catalyst, copper-zirconium oxide catalyst, copper-silicon dioxide catalyst, copper-aluminum oxide-zirconium oxide catalyst, copper-aluminum oxide-oxidation A chromium catalyst etc. are mentioned. Among these, copper-aluminum oxide catalyst, copper-chromium oxide catalyst, copper-aluminum oxide-zirconium oxide catalyst, or Raney nickel catalyst, Raney cobalt catalyst, Raney copper catalyst, palladium-activated carbon catalyst, platinum-activated carbon catalyst, etc. .

The amount of the catalyst may be an amount of catalyst that can be usually provided in the reaction apparatus. However, in the case of the gas-phase flow reaction apparatus, the feed weight of propanal per unit time with respect to the catalyst weight (WHSV: Weight) Hourly Space Velocity; unit, h ⁻¹ ), which can be used in the range of 0.1 to 20 h ⁻¹ in terms of WHSV value, and preferably in terms of catalyst life and yield, in terms of WHSV value of 0. in the range of from 5 7h ^-1, more preferably at WHSV value is preferably in the range from 1 to 6h ^-1.
In the third step, the reaction temperature is preferably set to 100 to 240 ° C, particularly preferably set to 120 ° C to 200 ° C.

The amount of hydrogen supplied in the third step is preferably such that the ratio of the number of moles of hydrogen supplied into the reactor to the number of moles of raw material (propanal) supplied into the reactor is in the range of 0.1 to 500. . A more preferred molar ratio range is from 0.1 to 400, and even more preferably from 0.1 to 300. When the hydrogen supply amount in the present invention satisfies the above range, 1-propanol can be produced with higher selectivity, which is economically preferable. When the 1-propanol production method of the present invention is carried out using one reactor described later, the supply amount of propanal and hydrogen in the catalyst layer in which the third step is performed is within the above range. It is preferable to adjust the feed amount of the raw material and the supply amount of hydrogen in the first step.

The method for producing 1-propanol of the present invention includes three steps as described above, but each step may be performed in a separate reaction apparatus, or the reaction may be performed in one reaction apparatus.
The reactor used in the method for producing 1-propanol of the present invention is not particularly limited as described above. For example, three gas phase flow reactors are used, each for conversion of glycerin to 1,2-propanediol, conversion of 1,2-propanediol to propanal, and conversion of propanal to 1-propanol. Thus, 1-propanol can be produced from glycerin.

As another method, for example, a method of producing 1-propanal with one reactor such as a gas phase reactor can be mentioned. Specifically, three catalyst layers are provided in the reaction apparatus, a catalyst for converting glycerin to 1,2-propanediol is filled in the upper part of the reaction apparatus, and 1,2- A catalyst for converting propanediol to propanal is charged, and a catalyst for converting propanal to 1-propanol is charged at the bottom of the reactor. Then, 1-propanol can be produced from glycerin by simultaneously supplying glycerin and hydrogen as raw materials from the upper part of the reactor.

The reaction time of the 1-propanol production method in this case is represented by a raw material feed volume (WHSV: Weight Hourly Space Velocity; unit, h ⁻¹ ) per unit time with respect to the catalyst layer volume, and a WHSV value of 0.1 to available in a range of 20h ^-1, preferably WHSV value in the range of 0.5 ~ 7h ^-1, more preferably at WHSV values, in the range of 1 ~ 6h ^-1. It is preferable to adjust the feed amount of the raw material and the supply amount of hydrogen so as to be within such a range in each catalyst layer. Moreover, the conditions described in each of the above steps can be used as the catalyst type and temperature conditions of each catalyst layer. Furthermore, the water content of the glycol used as a raw material can be the same as that described in the above-mentioned glycol production method.

As yet another method, a method using two reactors such as a gas phase reactor shown below can be used. The first reactor is provided with two catalyst layers, the top of the reactor is filled with a catalyst for converting glycerin to 1,2-propanediol, and the bottom of the reactor is 1,2-propanediol. Is charged with a catalyst for converting to propanal. The catalyst layer of the second reactor is filled with a catalyst for converting propanal to 1-propanol. Then, it is possible to produce 1-propanol by supplying glycerin and hydrogen to the first reactor and supplying the propanal and hydrogen obtained in the first reactor to the second reactor. .

In addition, a catalyst for converting glycerin into 1,2-propanediol is charged in the first reactor, and a catalyst for converting 1,2-propanediol into propanal is provided in the upper part of the second reactor. There is also a method in which the catalyst for charging and converting propanal into 1-propanol is charged at the bottom of the reactor. 1-propanol is also produced by supplying glycerin and hydrogen to the first reactor, and supplying 1,2-propanediol and hydrogen obtained in the first reactor to the second reactor. It is possible.
The ratio of the feed amount of raw material to the supply amount of hydrogen and the supply amount of hydrogen when using two reactors as described above are described in the glycol production method, the second step, and the third step. The conditions described in the above steps can be used as the catalyst type and temperature condition of each catalyst layer. Moreover, the above-mentioned conditions can be used for the water content of the raw material.

Hereinafter, the effects of the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

As the fixed bed atmospheric pressure gas flow reactor used in Examples and Comparative Examples, a reactor having an inner diameter of 17 mm and a total length of 300 mm was used. The length of the catalyst layer was set to 30 mm. Therefore, the volume occupied by the catalyst layer in the reactor was about 6.8 cm ³ . The reactor has a reaction crude liquid collection container (cooling device) having a carrier gas inlet and a raw material inlet at the upper end and a gas outlet at the lower end. The reaction crude liquid collected in the collection container as a result of the reaction was measured by gas chromatography, and after calibration curve correction, the remaining amount of raw materials such as glycerin and products such as 1,2-propanediol The yield was determined, and the conversion (mol%) and selectivity (mol%) were determined from this value. A commercially available catalyst having a particle size of 1.00 to 1.70 mm was used as the copper-based catalyst.

<Example 1>
(Influence of hydrogen flow rate)
A copper-aluminum oxide catalyst (NGC 242 manufactured by JGC Chemical Co., Ltd.) was used to flow hydrogen at a predetermined flow rate from the top of the reactor using a fixed bed atmospheric pressure gas flow reactor set to a length of 30 mm in the reactor. Then, a 30 wt% glycerin aqueous solution as a raw material was supplied to the catalyst layer at a rate of 1.8 g h ^{−1 and} the influence of the hydrogen flow rate on the reaction was observed. Table 1 shows the glycerol conversion rate and 1,2-propanediol selectivity when the reaction temperature is controlled at 210 ° C for the upper surface of the catalyst layer in the reactor and 175 ° C for the lower surface.
Under the reaction conditions where the glycerin conversion is 100%, the selectivity for 1,2-propanediol is approximately 85%, indicating that there are very few by-products.

<Example 2>
(Influence of reaction temperature)
A copper-aluminum oxide catalyst (NGC 242 manufactured by JGC Chemical Co., Ltd.) added 1.8 g h of a 30 wt% glycerin aqueous solution as a raw material from the top of a fixed bed atmospheric pressure gas flow reactor set to a length of 30 mm in the reactor. ^-1 rate, hydrogen was fed to the flow 360 ml min. catalyst ^layer-1 speed, saw the influence on the reaction of the temperature change of the catalyst layer. The ratio of the number of moles of hydrogen supplied to the number of moles of raw material supplied is 164. Table 2 shows the glycerol conversion and 1,2-propanediol selectivity when the reaction temperature is changed.
Under the reaction conditions in which the glycerin conversion is 100%, the 1,2-propanediol selectivity generally exceeds 90% in the reaction where the temperature at the lower part of the catalyst layer is 175 ° C. or lower, and is relatively high in the reaction at 190 ° C. It showed selectivity for the desired product.

<Example 3>
(Reactions with various catalysts)
Various commercially available catalysts were used, an aqueous glycerin solution having a glycerin concentration of 80% was used as a reaction raw material, the hydrogen flow rate was 240 ml min.- ¹ , the upper surface of the catalyst layer in the reactor was 210 ° C., and the lower surface was 170 ° C. .
Other conditions were the same as in Example 2. The ratio of the number of moles of hydrogen supplied to the number of moles of raw material supplied is 41. Table 3 shows glycerin conversion and 1,2-propanediol selectivity.
Whether the glycerin concentration was as high as 80% by weight or the catalyst containing copper was used, the selectivity of the target product could exceed 80% under high conversion conditions.

<Comparative Example 1>
The reaction was carried out under the condition that the molar ratio of hydrogen supply to the raw material supply was 30 or less. Hydrogen flow rate is 25 ml min. ^{Since the} reaction was carried out as ^-1 , the hydrogen flow rate ratio to the catalyst layer volume was 11. Other conditions were the same as in Example 1. The results are shown in Table 4.

<Comparative example 2>
By changing the reaction temperature, the effect of the temperature change of the catalyst layer on the reaction was observed. Other conditions were the same as in Example 2. The results are shown in Table 5.

In the following Examples and Comparative Examples, production examples of 1-propanol will be specifically described.
The fixed bed atmospheric pressure gas flow reactor used in the following examples and comparative examples is a reactor having an inner diameter of 17 mm and an overall length of 300 mm, similar to that used in the glycol production method described above. It has a reaction crude liquid collection container (cooling device) having a mouth and a raw material inlet and having a gas outlet at the lower end.

The catalyst used in the following Examples and Comparative Examples will be described. The catalyst for converting glycerin to 1,2-propanediol is a copper-aluminum oxide catalyst, and 1,2-propanediol is converted to propanal. Sometimes the catalyst is silicon dioxide-supported phosphotungstic acid, and the reaction catalyst from propanal to 1-propanol is a copper-aluminum oxide catalyst. The copper-aluminum oxide catalyst is a commercially available product (trade name: N-242, manufactured by JGC Chemical Co., Ltd.), and the silicon dioxide-supported phosphotungstic acid is dissolved in commercially available phosphotungstic acid (manufactured by Wako Pure Chemicals, special grade) in water. A catalyst supported on a commercially available silicon dioxide (trade name: Caractect Q10, manufactured by Fuji Silysia Chemical Co., Ltd.) by an impregnation method so as to have a supported amount of 30% by weight was used.
The reaction crude liquid collected in the collection container is analyzed by gas chromatography, and after calibration curve correction, the yield of 1-propanol and the like and the remaining amount of raw materials such as glycerin are determined, and the conversion rate ( Mol%) and selectivity (mol%).

<Example 4>
(Synthesis of 1-propanol from 1,2-propanediol Reaction temperature 1)
Using a reaction apparatus in which 0.3 g of a silicon dioxide catalyst supporting a heteropoly acid is placed on the upper part of the catalyst layer and 0.5 g of a copper-aluminum oxide catalyst (N242 manufactured by JGC Chemical Co., Ltd.) is placed on the lower part of the catalyst layer, the raw material A 30 wt% aqueous solution of 1,2-propanediol was supplied at a rate of 1.8 g h ^{−1 at} a rate of 30 ml per minute, and the reaction was carried out at different reaction temperatures. The 1,2-propanediol conversion rate, 1-propanol selectivity, and 1-propanol yield were as shown in Table 6 below. The ratio of moles of hydrogen to moles of raw material was 11.3.

<Example 5>
(Synthesis of 1-propanol from 1,2-propanediol, catalytic amount)
The reaction was carried out at a reaction temperature of 200 ° C. while changing the amount of catalyst in the lower catalyst layer described in Example 4. The 1,2-propanediol conversion, 1-propanol selectivity, and 1-propanol yield were as shown in Table 7 below.

<Example 6>
(Synthesis of 1-propanol from 1,2-propanediol, reaction temperature 2)
The reaction was performed according to Example 4 except that the reaction temperature at the upper part of the catalyst layer and the lower part of the catalyst layer was changed. The 1,2-propanediol conversion, 1-propanol selectivity, and 1-propanol yield were as shown in Table 8 below.

<Example 7>
(Synthesis of 1-propanol from 1,2-propanediol, hydrogen flow rate)
The reaction was carried out according to Example 4 except that the hydrogen flow rate was changed and the reaction temperature was fixed at 200 ° C. The conversion rate of 1,2-propanediol, 1-propanol selectivity, and 1-propanol yield were as shown in Table 9 below.

<Example 8>
(Synthesis of 1-propanol from glycerin)
8.7 g of a copper-aluminum oxide catalyst (N242 manufactured by JGC Chemical Co., Ltd.) is placed on the upper part of the catalyst layer, 0.3 g of a silicon dioxide catalyst supporting a heteropoly acid is placed on the middle part of the catalyst layer, and copper- Using a reactor equipped with 0.5 g of an aluminum oxide catalyst (N242 manufactured by JGC Chemical Co., Ltd.), a 30 wt% aqueous solution of glycerin as a raw material at a rate of 1.8 g h ⁻¹ and hydrogen at 360 ml min. ^The reaction was carried out at a rate of ^-1 while changing the temperature of the upper and lower surfaces of the upper part of the catalyst layer, the reaction temperature of the middle part of the catalyst layer and the lower part of the catalyst layer. The ratio of the number of moles of hydrogen supplied to the number of moles of raw material supplied was 164. The glycerin conversion, 1-propanol selectivity, and 1-propanol yield were as shown in Table 10 below.

As the fixed bed pressurized gas phase flow reactor used in the experiments whose results are shown in Table 11 below, a reactor having an inner diameter of 28 mm and a total length of 1000 mm was used. The length of the catalyst layer was set to 150 mm. Therefore, the volume occupied by the catalyst layer in the reactor was about 92.4 cm ³ . The reactor has a carrier gas inlet and a raw material inlet at the upper end, and a reaction crude liquid collection container (cooling device) from which gas is discharged via a back pressure valve at the lower end. The reaction crude liquid collected in the collection container as a result of the reaction was measured by gas chromatography, and after calibration curve correction, the remaining amount of raw materials such as glycerin and products such as 1,2-propanediol The yield was determined, and the conversion (mol%) and selectivity (mol%) were determined from this value. A commercially available catalyst having a particle size of 1/8 inch tablet (Cu-0825T, manufactured by NE Chemcat Corp.) was used as the copper-based catalyst. The raw material glycerin was 80% in concentration (the rest was water).
Hydrogen was supplied from the upper part of the reactor at each supply amount shown in Table 11, and raw material glycerin was supplied by WHSV described in Table 11.
Table 11 shows the reaction rate, the selectivity for acetol (HA), the selectivity for propylene glycol (PG), and the yield.

Looking at the results shown in Table 11, for example, the experiment No. Comparing the results of 7 and 8, it was found that the selectivity of PG (propylene glycol) was higher and the selectivity of HA (acetol) was lower in the reaction under pressure than in the reaction under atmospheric pressure. Further, even when the reaction is carried out under a condition where the molar ratio of hydrogen to glycerin is smaller than that under atmospheric pressure, the high selectivity to PG means less hydrogen consumption, which is economically advantageous. It shows that there is.
In the above experiment No. Similar results were obtained by comparing 11 and 12 and comparing 14 and 15.

Claims (19)

1. A method for producing glycol from glycerin, characterized by using a catalyst containing copper as a component and reacting under atmospheric pressure or under pressure in the presence of hydrogen.
2. The production method according to claim 1, wherein the reaction is performed under atmospheric pressure.
3. The method according to claim 2, wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 150 to 500.
4. The method according to claim 2, wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 150 to 400.
5. The method according to claim 2, wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 150 to 300.
6. The production method according to claim 1, wherein the reaction is carried out under pressure.
7. The method according to claim 6, wherein the ratio of the number of moles of hydrogen supplied to the reaction to the number of moles of raw material supplied to the reaction is 20 to 30.
8. The first stage reaction in which glycerin is dehydrated and acetol is generated is performed at 150 to 260 ° C., and the second stage reaction in which hydrogen is added to the generated acetol to generate glycol is performed at 100 to 220 ° C. The manufacturing method according to any one of claims 1 to 7.
9. The production method according to claim 8, wherein the first-stage reaction is performed at 150 to 225 ° C, and the second-stage reaction is performed at 120 to 175 ° C.
10. The production method according to claim 8, wherein the first stage reaction is performed at 150 to 200 ° C, and the second stage reaction is performed at 120 to 160 ° C.
11. The production method according to claim 8, wherein the first stage reaction is performed at 230 to 260 ° C, and the second stage reaction is performed at 150 to 220 ° C.
12. The production method according to claim 8, wherein the first stage reaction is performed at 240 to 250 ° C, and the second stage reaction is performed at 150 to 175 ° C.
13. The method according to any one of claims 1 to 12, wherein the glycol is 1,2-propylene glycol.
14. A first step of converting glycerin to 1,2-propylene glycol using the production method according to claim 13, and a second step of converting 1,2-propylene glycol produced in the first step to propanal. And a third step of converting the propanal produced in the second step to 1-propanol.
15. The method according to claim 14, wherein the second step is performed using a catalyst comprising a heteropolyacid or a heteropolyacid-catalyst support complex.
16. The production method according to claim 15, wherein the heteropolyacid or the heteropolyacid of the heteropolyacid-catalyst support complex includes any one selected from silicotungstic acid, silicomolybdic acid, phosphotungstic acid and phosphomolybdic acid.
17. The production method according to claim 15, wherein the heteropolyacid or the heteropolyacid of the heteropolyacid-catalyst support complex is silicotungstic acid.
18. The method according to any one of claims 14 to 17, wherein the third step is performed using a hydrogenation catalyst containing at least one catalyst component selected from copper, platinum, nickel, palladium, and ruthenium. The production method according to claim 1.
19. The method according to any one of claims 14 to 17, wherein the third step is performed using a hydrogenation catalyst containing any one or more kinds of catalyst components selected from copper, nickel, and palladium. The manufacturing method as described.