KR20120096125A - Fabrication method of 1,3-butadiene and 2-butanone from 2,3-butanediol - Google Patents

Abstract

PURPOSE: A manufacturing method of 1,3-butadiene and 2-butanone is provided to have excellent conversion rate and yield, maintaining extremely high catalytic activity, and to able to long term stably manufacture 1,3-butadiene and 2-butanol. CONSTITUTION: A manufacturing method of 1,3-butadiene and 2-butanone comprises a step of manufacture 1,3-butadine from 2,3-butandiol under the presence of a catalyst selected from hydroxyapatite, calcium pyrophosphate, or a mixture thereof. The dehydration of the 2,3-butanediol is conducted under a condition of 2,3-butane diol liquid hour space velocity(LHSV), 340-450 °C, and 1-6 atm. The catalyst is a functional catalyst manufacturing 1,3-butadiene and 2-butanone from 2,3-butandiol.

Description

Method for producing 1,3-butadiene and 2-butanone from 2,3-butanediol {Fabrication Method of 1,3-Butadiene and 2-Butanone from 2,3-Butanediol}

The present invention relates to a method for preparing 1,3-butadiene and 2-butanone (2-Butanone, Methyl Ethyl Ketone) from 2,3-butanediol, In detail, the present invention relates to a new method for obtaining 1,3-butadiene and 2-butanone in a high yield from a bioplatform compound, 2,3-butanediol, over a long period of time.

2,3-butanediol (BDO; 2,3-butanediol) is generally prepared by methods produced by fermentation. In particular, due to the surge in demand for synthetic rubber instead of raw rubber during World War II, it was mass-produced as raw material of butadiene.However, as 2,3-butanediol is produced at a low price by supplying butadiene from petroleum in bulk, some fine chemicals are used. Restricted to, greatly reduced.

As the price of naphtha, a raw material of butadiene due to high oil prices, is increasing, the utilization rate of naphtha cracking facilities is reduced by about 10-15%, and the utilization rate will decrease further due to deterioration in the profitability of naphtha cracking facilities due to the recent expansion of ethylene cracking facilities in the Middle East. As a result, butadiene, 2-butanone, and 2,3-dimethyloxirane are expected to have a big disruption in the supply and demand of butadiene, butadiene from biomass (2,3-butanediol), an petroleum substitute, is used to reduce the dependence on petroleum. R & D for preparing 2-butanone and 2,3-dimethyloxirane is being promoted.

As a method for producing 2,3-butanediol (BDO), fermented strains such as bacteria Klebsiella pneumoniae, Bacillus polymyxa or Enterobacter aerogenes are used, and pentoses, xylose and arabinose, etc. Is synthesized by optimizing the culture conditions (temperature, pH, medium composition, carbon source, etc.), and separating and purifying from the fermentation broth using multistage vacuum distillation, solvent extraction, and micropore Teflon membrane separation. (Syu, M.-J. Appl. Microbiol. Biotechnol (2001) 55: 10-18).

2,3-butanediol (BDO) is classified into dry BDO and wet BDO according to the use. Dry BDO has a moisture content of 5% or less and wet BDO has a water content of 5-80%. In the dehydration reaction, dry BDO and Wet BDO with water content of 20% or less are mainly used.The more water is contained in the dehydration reaction, the more the water is dehydrated, the dehydration product is reversely reacted with the reactant, so that the conversion rate is reduced and the evaporation energy is lost. This is because the energy consumption is large.

Butadiene is an important material as a raw material of synthetic rubber, and it becomes a raw material of butadiene styrene rubber (SBR), butadiene acrylonitrile rubber (NBR), and polybutadiene. It is also used as a raw material for chloroprene, adiponitryl, maleic anhydride and the like.

2-Butanone (Methyl Ethyl Ketone) is used in the fine chemical industry as a synthetic solvent, fuel additive, dispersant and solvent.

A method for preparing butadiene by dehydration of butanediol is disclosed in US Pat. No. 2,444,538. As butanediol, 1,3-butanediol was used, and as a catalyst, a mixture of sodium phosphate-calcium phosphate-butyl phosphate mixture catalyst was used, and 80% of 1,3-butanediol aqueous solution was reacted at a reaction temperature of 250 to 300 ° C at atmospheric pressure (LHSV). , Liquid Hour Space Velocity) was supplied as 0.28, the yield of butadiene with a purity of 97% was 77% at the reaction time 20 hours, the yield was reduced to 61% after 42 hours.

A method for preparing butadiene by dehydration of 2,3-butanediol is disclosed in US Pat. No. 2,527,120. As a catalyst, kaolin, silica gel, activated carbon, and the like were used as catalysts, and a butadiene was synthesized by supplying a 50% 1,3-butanediol-acetic anhydride solution at a reaction temperature of 500 to 580 ° C and atmospheric pressure. However, the reaction yield and reaction time were not presented in detail.

As a method for preparing diolefin from diols, US Pat. No. 3,758,612 used a lithium phosphate catalyst having a lithium / phosphorus ratio of 2.2 to 3. Methyl-2,3-butanediol was used as the diol, and isoprene, a diolefin, and methyl isopropyl ketone, a ketone compound, were synthesized as products. When methyl-2,3-butanediol was reacted by supplying liquid hour space velocity (LHSV) 1.0 at a reaction temperature of 400 ° C., the yield was 100% and the yield of isoprene was 62-64%, and methyl isopropyl ketone The yield of was 29-30%. However, the results of the change in activity according to the reaction time are not presented, and the catalyst stability seems to be improved.

In addition, US Patent No. 3,957,900 uses a mixed catalyst of orthophosphoric acid and pyrophosphoric acid of lithium, sodium, strontium, and barium. Methyl-2,3-butanediol was used as the diol, and isoprene, a diolefin, and methyl isopropyl ketone, a ketone compound, were synthesized as products. The reaction was carried out by using Li ₃ NaP ₂ O ₇ catalyst and supplying methyl-2,3-butanediol at 1.0 ° C atmospheric pressure at room temperature (LHSV, Liquid Hour Space Velocity) 1.0, and after 1 hour, 100% conversion. The yield of isoprene was 86% and the yield of methyl isopropyl ketone was 12%. Since the strength of the catalyst was weak and the activity was large, a Li ₃ NaP ₂ O ₇ -Na ₂ HP ₂ O ₇ catalyst mixed with sodium pyrophosphate was used. When methyl-2,3-butanediol was reacted with a space velocity (LHSV) of 1.0 at a reaction temperature of 400 ° C, the strength of the catalyst was increased. However, after 1 hour, the conversion was 91% and the yield of isoprene was 30%. , The yield of methyl isopropyl ketone was 18%. At 14 hours, the yield was 85%, the yield of isoprene was 16%, and the yield of methyl isopropyl ketone was 19%, indicating a decrease in activity and a decrease in yield of isoprene, a diolefin.

A method for synthesizing diolefins by dehydration of aldehydes has been proposed in US Pat. No. 4,628,140. Aldehydro is 2-methylbutylaldehyde, dehydration product isoprene and boron phosphate having a phosphoric acid / boron ratio of 0.8 was used as a catalyst. In particular, 2.5% of butylcatechol, an aromatic compound, was added as an activity-inhibiting agent, and 2-methylbutylaldehyde was reacted with a space velocity (LHSV) of 2.25 at a reaction temperature of 275 ° C. After 2 hours, the conversion rate was 33%, The yield of isoprene was 23%, the conversion was 18% and the yield of isoprene was 14% at 32 hours. Although the degree of deactivation is gentle, the initial activity is low, and the activity is decreasing.

A method of synthesizing 2-butanone (2-Butanone, Methyl Ethyl Ketone) by dehydration in dialcohol is carried out using alumina [Kannan, s. V .; Pillai, c. N. Indian J. Chem. 1969, 7, 1164-66 and bentonite [Bourns, a. N .; Nicholls, R. V. Can. J. Res. 1947, 25B, 80-89] or the use of phosphorus pentoxide and the use of liquid acids sulfuric acid or phosphoric acid [Furhhaski, S .; Ohara, K. J. Agri. Chem. Soc. Jpn. 1948, 17, 315-20]. However, only acidic catalyst is used for the catalyst which is dehydrated in diol and yields only 91% in butanone, and acid-base complex catalyst is mainly used as a catalyst for dehydrating two waters in one molecule with diolefin. In the case of acid-base complex catalysts, the activity is low for commercial production, and improvements in thermal stability, hydrothermal stability, and reaction stability are required.

The present invention provides a method for preparing 1,3-butadiene and 2-butanone by dehydration of 2,3-butanediol, maintains very high activity, has excellent conversion and yield, and is extremely stable. It is to provide a production method capable of long-term reaction.

In addition, the present invention provides a catalyst for producing 1,3-butadiene and 2-butanone by dehydration of 2,3-butanediol, and a method for preparing the same, which is easy to prepare, has excellent reaction stability, and It is to provide a catalyst having a high activity and a high selectivity, and an extended catalyst life and a method for preparing the same.

Hereinafter, a method for preparing 1,3-butadiene and 2-butanone of the present invention, a catalyst used in the method, and a method for preparing the catalyst will be described in detail. Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

Applicant uses various catalysts to prepare 1,3-butadiene and 2-butanone (2-Butanone, Methyl Ethyl Ketone) from 2,3-butanediol As a result of the experiment, it was confirmed that when hydroxyapatite and calcium pyrophosphate were used as catalysts, the activity, selectivity, and reaction stability of the dehydration reaction were greatly increased, thereby completing the present invention.

In addition, the Applicant has examined in detail the kind of precursor, precipitate pH, stirring condition, heat treatment temperature, etc., in the synthesis of calcium phosphate salts (hydroxyapatite, calcium pyrophosphate) using the phosphate precursor and calcium precursor. It was confirmed that the calcium phosphate salt synthesized under the conditions and methods further increased the activity, selectivity, and reaction stability of the dehydration reaction, thereby completing the present invention.

Hereinafter, a method for preparing 1,3-butadiene and 2-butanone according to the present invention will be described in detail.

The preparation method according to the invention is characterized in that 1,3-butadiene is prepared from 2,3-butanediol in the presence of a catalyst selected from hydroxyapatite, calcium pyrophosphate, or mixtures thereof, hydroxyapatite, pyrophosphate It is characterized by the preparation of 2-butanone from 2,3-butanediol in the presence of a catalyst selected from calcium, or mixtures thereof.

The catalyst is a dehydration catalyst of 2,3-butanediol and is characterized by a high functional catalyst. The hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) or the calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) may be used as a catalyst, the catalyst is hydroxyapatite (Ca ₅ (PO ₄ Hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) of the catalyst when both ( ₃ ) (OH)) and calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) are contained: calcium pyrophosphate (Ca) The weight ratio of ₂ (P ₂ O ₇ )) is preferably 1: 0.5 to 1.5. The catalyst includes a powder or porous sintered body shape, and the porous sintered body shape includes a pellet shape.

As described above, the preparation method according to the present invention is achieved by employing hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)), calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) or a mixture thereof as a catalyst. The catalyst maintains extremely high activity even in the long-term dehydration reaction, so that the long-term continuous reaction is possible. The long-term reaction has a high conversion rate of 2,3-butanediol, and high 1,3-butadiene and 2-butanone. It has the advantage of being produced in yield.

The method for preparing 1,3-butadiene and 2-butanone according to the present invention may be a continuous reaction or a batch reaction using a fixed bed reactor. As a reaction method using a fixed reactor, a catalyst pellet (pellet) according to the present invention is charged to a fixed reactor and the reactant 2,3-butanediol is continuously supplied to the reactor to produce a product. At this time, the filling rate of the catalyst in the fixed reactor is preferably 30 to 70% by volume. In the case of a continuous batch reaction, it is preferable to use 1 to 10% by weight of the catalyst.

The stability of the catalyst which is hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)), calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) or a mixture thereof is very excellent and high activity is maintained for a long time. It is preferable that the manufacturing method of this invention is a continuous reaction which continuously produces 1, 3- butadiene and 2-butanone by continuously dehydrating 2, 3- butanediol.

As described above, the production method of the present invention is selected from at least one selected from the group consisting of hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) and calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )). Dehydration of 2,3-butanediol in the presence of a catalyst to produce 1,3-butadiene and 2-butanone, the dehydration reaction is a reaction temperature of 340 to 450 ℃, reaction pressure of 1 to 6 atm and It is characterized in that it is carried out under the conditions of 2,3-butanediol liquid space velocity (LHSV) of 0.3 to 1.5 h ^-1 .

The reaction temperature, the reaction pressure and the liquid phase space velocity are conditions for producing 1,3-butadiene and 2-butanone with a selectivity of 70 mol% or more. When the feed rate of the reactants is less than 0.3 hr ^−1, the activity of the catalyst is excessively increased, so that hydrocracking side reactions proceed and the selectivity decreases. And if the reaction temperature is less than 340 ℃, or if the reaction pressure is more than 6atm, the feed rate of 2,3-butanediol exceeds 1.5hr ^-1 , the conversion rate is lowered, the other reaction conditions must be severely increased and the cost in the separation and recovery stage of the product Will increase.

Hereinafter, a catalyst for preparing 1,3-butadiene and 2-butanone according to the present invention and a method for preparing the same will be described in detail.

The catalyst according to the invention is characterized in that it is a catalyst for preparing 1,3-butadiene and 2-butanone from 2,3-butanediol, the catalyst is hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) and Calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) is characterized in that at least one catalyst selected from the group consisting of.

Specifically, the catalyst is characterized in that the catalyst for continuously producing 1,3-butadiene and 2-butanone by continuously dehydrating 2,3-butanediol, even in 100 hours of continuous dehydration reaction of more than 95 mol% It is characterized by a catalyst having a conversion rate and having a yield of 1,3-butadiene and 2-butanone of at least 70 mol% (sum of yield of 1,3-butadiene and 2-butanone yield).

A method for preparing a catalyst for preparing 1,3-butadiene and 2-butanone from 2,3-butanediol according to the present invention comprises the steps of: (a) preparing an aqueous solution of phosphate by mixing an alkali salt with an aqueous solution containing phosphoric acid; (b) preparing a calcium phosphate salt by mixing and stirring the aqueous solution of calcium precursor to the aqueous solution of phosphate; And (c) hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)), calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) or a mixture thereof by heat-treating the prepared calcium phosphate salt at 300 to 700 ° C. Preparing a phosphorus catalyst; and there is a feature performed.

The phosphoric acid of step (a) is orthophosphoric acid (H ₃ PO ₄ ), pyrophosphoric acid (H ₄ P ₂ O ₇ ), tripolyphosphoric acid (H ₅ P ₃ O ₁₀ ) and tetrapolyphosphoric acid (H ₆ P ₄ O ₁₃ ) In the at least one selected feature, the alkali salt is preferably caustic soda (sodium hydroxide, NaOH), potassium hydroxide (KOH) and lithium hydroxide (LiOH), of which caustic soda (NaOH) is most preferably used. .

In the step (a), the alkali salt is added so that the pH of the aqueous solution of phosphate is 10.0 to 12.0. Accordingly, the aqueous solution of phosphate is characterized in that the pH is 10.0 to 12.0 so that the phosphate is completely dissolved and stable.

The mixing of the alkali salts is preferably carried out by dropping an aqueous solution containing an alkali salt (alkali salt aqueous solution), and the dropping of the aqueous alkali salt solution is preferably performed over 20 minutes to 2 hours. At this time, the mixing may be performed when the alkali salt solution and the phosphoric acid solution is mixed.

The calcium precursor of step (b) is one or more materials selected from calcium chloride, calcium nitrate, calcium sulfate and calcium acetate, the phosphoric acid concentration of the aqueous solution of phosphate of step (b) is 0.1 to 0.4 normal, the calcium precursor aqueous solution of The calcium concentration is 1.0 to 4.0 normal, and the calcium precursor aqueous solution is characterized in that it is mixed with the aqueous phosphate solution so that the molar ratio of phosphorus: calcium is 1: 0.7 to 1.5.

In the mixing of the step (b), the calcium precursor aqueous solution is characterized in that the drop of the phosphate solution at a rate of 3 to 10ml / min. By dropping the calcium precursor aqueous solution at a rate of 3 to 10ml / min, it is possible to prevent the formation of unwanted abnormalities, has a very large specific surface area during the heat treatment of the step (c), calcium phosphate to maintain excellent activity for a long time Salt (hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)), calcium pyrophosphate (Ca ₂ (P ₂ O ₇ ) or mixtures thereof) catalysts are prepared.

The stirring of the step (b) is characterized in that it is carried out at 60 to 90 ℃. When the mixture is stirred below 60 ° C, the binding of calcium phosphate salt is not sufficient, so the uniform dispersibility of hydroxyapatite or calcium pyrophosphate and the formation of particles are low. Therefore, the activity decreases. When heating at 90 ° C or higher, hydroxyapatite and diphosphate The strong binding of disodium calcium acid leads to the formation of byproducts of calcium phosphate salts, which are converted to sodium phosphate (Tri-Sodium Phosphate, Na ₃ PO ₄ ) and sodium calcium phosphate (CaNa ₂ (P ₂ O ₇ )). There is a risk of reduced selectivity.

The heat treatment of step (c) is characterized in that it is carried out at 300 to 700 ℃ in air, preferably 400 to 600 ℃ heat treatment for 3 to 10 hours. Calcium phosphate salt particles (hydroxyapatite, calcium pyrophosphate, or mixtures thereof) are densified when the heat treatment temperature exceeds 700 ° C., and the catalytic activity is lowered. When the heat treatment temperature is lower than 300 ° C., hydroxyapatite or calcium pyrophosphate is used. Incomplete particles are produced, resulting in a lower conversion.

The preparation method includes the steps of (b) and before (c) step, (b2) recovering the prepared calcium phosphate salt and drying it to a size of 5 to 100 μm; And (b3) shaping the pulverized calcium phosphate salt into pellets.

The slurry of calcium phosphate salt is prepared by the step (b), and the recovery of the calcium phosphate salt may be performed by filtration of the slurry, and the washing step of filtering the calcium phosphate salt obtained by filtration with distilled water and then filtering It is preferable to carry out more.

Preferably, the calcium phosphate salt cake obtained by filtration and washing is preferably dried at 80 to 120 ° C. for 5 to 30 hours, and the dried cake is preferably ground to a powder of 5 to 100 μm size using a grinder. At this time, the calcium phosphate salt cake may be spray dried into particles having a size of 5 to 100 μm using a spray dryer.

Then, the pulverized powder is molded into pellets in a tablet machine. In this case, 0.5 to 5% by weight of the graphite (Graphite) used as a lubricant and pore control agent to the powder may be mixed into a pellet. Thereafter, a pellet catalyst is prepared by the heat treatment in step (c).

The pellet catalyst is preferable for the production of 1,3-butadiene and 2-butanone in a continuous reaction, and when producing 1,3-butadiene and 2-butanone in a batch reaction, the (b3 A powdery catalyst obtained by heat-treating the pulverized powder of step (b2) may be used without passing through the step).

The manufacturing method of 1,3-butadiene and 2-butanone according to the present invention has the advantage of producing high yields of 1,3-butadiene and 2-butanone, and stably 1,3-butadiene and 2 -There is an advantage to prepare butanone.

The catalyst for preparing 1,3-butadiene and 2-butanone according to the present invention has the advantage of being a high activity and high selectivity dehydration catalyst, has excellent reaction stability, and has the advantage of maintaining high activity even in long-term reactions, and has an extended lifetime. There is an advantage to having.

The production method of the catalyst for producing 1,3-butadiene and 2-butanone according to the present invention is easy to manufacture, has excellent reaction stability, has very high activity and high selectivity, and has the advantage of producing a catalyst having an extended lifetime. have.

1 shows the results of X-ray diffraction analysis on the catalyst prepared in Example 1 of the present invention,
2 shows the results of X-ray diffraction analysis for the catalyst prepared in Example 2 of the present invention,
3 shows the results of X-ray diffraction analysis for the catalyst prepared in Example 3 of the present invention,
4 shows the results of X-ray diffraction analysis for the catalyst prepared in Comparative Example 1 of the present invention.

The present invention will be described in detail through the following examples. However, the following examples are merely examples of the present invention, and the claims of the present invention are not limited thereto.

(Example 1)

Hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) Preparation of Catalyst

67.58 g of 50 wt% tetrapolyphosphoric acid (H ₆ P ₄ O ₁₃ ) aqueous solution was dissolved in deionized water to prepare an aqueous 500 ml phosphoric acid solution. 36.0 g of caustic soda (NaOH) was added to the aqueous solution of phosphoric acid for 30 minutes and stirred to prepare an aqueous solution of sodium phosphate (pH 11.1). 48.52 g of calcium chloride (CaCl ₂ · 2H ₂ O) was dissolved in deionized water to prepare a 200 ml aqueous solution of calcium precursor, and an aqueous solution of calcium precursor was added to the aqueous solution of sodium phosphate at a rate of 7 ml / min at room temperature for 30 minutes and at 80 ° C. for 2 hours. Stirring produced a calcium phosphate slurry (pH 5.7). After stirring was complete, the slurry solution was filtered, 600 ml of deionized water was added, dispersed, stirred for 20 minutes, and filtered to obtain a hydroxyapatite (Ca ₅ (PO ₄ ) ₃ OH) calcium phosphate cake.

The filtered calcium phosphate cake was dried at 80 ° C. for at least 6 hours. The dry matter was ground to a size of 20-40 mesh and calcined in air at 500 ° C. for 6 hours. As a result of XRD analysis of the calcined catalyst in air, the structure of hydroxyapatite (Ca ₅ (PO ₄ ) ₃ OH) was confirmed as shown in FIG. 1, and the specific surface area by BET analysis was 37.4 m 2 / g.

Preparation of 1,3-butadiene and 2-butanone

6 ml (4.32 g) of the catalyst prepared in Example 1 was charged to a Pyrex stainless tubular reactor having an internal diameter of 6 mm, and 2,3-butanediol was reacted at a reaction temperature of 380 ° C. and 2 atm pressure of liquid hour space velocity (LHSV). ) It was supplied to 0.50hr ^-1 (flow rate 3ml / hr) and dehydrated. The product was recovered as a liquid sample using an ice-cold collector, and the gas that did not condense into liquid was quantitatively analyzed by gas chromatography (GC) equipped with a DB-WAX column by sampling the gas sample with a gas collection syringe. Was done. As a result of analysis, 1,3-butadiene and 2-butanone were the main products, and in addition, 2,3-dimethyloxirane, acetoin, 1-butene-3-ol and the like were produced. The results in Table 1 below summarize the reaction results in 100 hours of reaction, and are expressed in mol%.

(Example 2)

Calcium Pyrophosphate (Ca ₂ (P ₂ O ₇ )) Preparation of Catalysts and Preparation of 1,3-butadiene and 2-butanone

35.6 g of pyrophosphate (H ₄ P ₂ O ₇ ) was dissolved in deionized water to prepare an aqueous 500 ml phosphoric acid solution. 36.0 g of caustic soda (NaOH) was added to the aqueous solution of phosphoric acid for 30 minutes and stirred to produce an aqueous solution of sodium phosphate (pH 11.2). 52.9 g of calcium chloride (CaCl ₂ · 2H ₂ O) was dissolved in deionized water to prepare a 200 ml aqueous solution of calcium precursors. An aqueous solution of calcium precursors was added to the aqueous solution of sodium phosphate at a rate of 7 ml / min at room temperature for 30 minutes and at 80 ° C. for 2 hours. Stirring produced a calcium phosphate slurry. After the stirring was completed, the slurry solution was filtered, 600 ml of deionized water was added thereto, dispersed, stirred for 20 minutes, and filtered, and the filtered calcium phosphate cake was dried at 80 ° C. for at least 6 hours. The dry matter was ground to a size of 20-40 mesh and calcined in air at 500 ° C. for 6 hours.

As a result of analyzing the catalyst treated by XRD with XRD, calcium pyrophosphate (Ca 2 ₍ P ₂ O ₇ )) structure was confirmed as shown in FIG. 2, except that the catalyst prepared in Example 2 was used. Similarly, 1,3-butadiene and 2-butanone were prepared, and the results at 100 hours of the reaction are summarized in Table 1 below.

(Example 3)

Hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) Preparation of Catalysts and Preparation of 1,3-butadiene and 2-butanone

35.0 g of an aqueous 84 wt% orthophosphoric acid (H ₃ PO ₄ ) solution was dissolved in deionized water to prepare an aqueous 500 ml phosphoric acid solution. 36.0 g of caustic soda (NaOH) was added to the aqueous solution of phosphoric acid for 30 minutes and stirred to produce an aqueous solution of sodium phosphate (pH 11.2). 52.9 g of calcium chloride (CaCl ₂ · 2H ₂ O) was dissolved in deionized water to prepare a 200 ml aqueous solution of calcium precursors. An aqueous solution of calcium precursors was added to the aqueous solution of sodium phosphate at a rate of 7 ml / min at room temperature for 30 minutes and at 80 ° C. for 2 hours. Stirring produced a calcium phosphate slurry. After the stirring was completed, the slurry solution was filtered, 600 ml of deionized water was added thereto, dispersed, stirred for 20 minutes, and filtered, and the filtered calcium phosphate cake was dried at 80 ° C. for at least 6 hours. The dry matter was ground to a size of 20-40 mesh and calcined in air at 500 ° C. for 6 hours.

As a result of analyzing the catalyst treated to XRD by XRD, hydroxyapatite (Ca ₅ (PO ₄ ) ₃ OH) structure was confirmed as shown in FIG. 3, except that the catalyst prepared in Example 3 was used. Similarly, 1,3-butadiene and 2-butanone were prepared, and the results at 100 hours of the reaction are summarized in Table 1 below.

(Table 1)

(Comparative Example 1)

Sodium pyrophosphate (CaNa) ₂ (P ₂ O ₇ )) Preparation of Catalysts and Preparation of 1,3-butadiene and 2-butanone

Instead of pyrophosphate (H ₄ P ₂ O ₇ ), 26.6 g of sodium pyrophosphate (Na ₄ (P ₂ O ₇ )) was dissolved in 500 ml of deionized water, and an aqueous solution of calcium precursor was added to the aqueous solution of sodium phosphate at room temperature. A catalyst was prepared in the same manner as in Example 2, except that the mixture was added at a rate of 7 ml / min for 30 minutes and stirred at 95 ° C. for 2 hours to produce a calcium phosphate slurry. As a result of analyzing the catalyst treated by XRD with XRD, the structure of sodium pyrophosphate (CaNa ₂ (P ₂ O ₇ )) was confirmed, and it was similar to Example 1 except that the catalyst prepared in Comparative Example 1 was used. 1,3-butadiene and 2-butanone were prepared, and the results at 50 hours of the reaction are summarized in Table 2 below. In this case,% in Table 2 means mol%.

(Table 2)

As can be seen from Tables 1 to 2, sodium pyrophosphate calcium compared to hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) and calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) catalyst according to the present invention In the case of the (CaNa ₂ (P ₂ O ₇ )) catalyst, the conversion rate is very low, and the selectivity of 1,3-butadiene and 2-butanone is also low.

(Examples 4 to 9)

Preparation of 1,3-butadiene and 2-butanone

Using the catalyst of Example 1, the reaction temperature, reaction pressure, reactant space velocity during 2,3-butanediol dehydration reaction was changed to the conditions shown in Table 3 below to 1,3-butadiene and 2 -Butanone was prepared and reacted The reaction results at 50 hours are summarized in Table 3 below. In this case,% in Table 3 means mol%.

(Table 3)

In the range of the reaction temperature, the reaction pressure and the reactant space velocity, the higher the reaction temperature, the higher the selectivity of butadiene, and the lower the reaction temperature, the lower the selectivity of butadiene and the intermediate 1-butene-3- which is converted into butadiene. It can be seen that the selectivity of the ol increases. The higher the reaction pressure, the higher the selectivity of butadiene and the higher the conversion rate. Increasing the space velocity of the reactants reduced the conversion, but did not decrease significantly, butadiene selectivity slightly decreased, 1-butene-3-ol selectivity increased. However, the high conversion of butanediol and the selectivity of butadiene and butanone were found to be high at about 80-88% under the above reaction conditions.

(Comparative Examples 2 to 7)

Preparation of 1,3-butadiene and 2-butanone

Using the catalyst of Example 1, the reaction temperature, reaction pressure, reactant space velocity during 2,3-butanediol dehydration reaction was changed to the conditions shown in Table 4 to 1,3-butadiene and 2 -Butanone was prepared, and the reaction result in 50 hours of reaction was summarized in Table 4 below. In this case,% in Table 4 means mol%.

(Table 4)

As can be seen from Table 4, when the reaction is carried out at a reaction temperature outside the range of the reaction temperature 340 ~ 450 ℃, butadiene selectivity is lowered, the reaction pressure 1 to 6 atm, when the reaction is carried out at a reaction pressure outside the range, It can be seen that the selectivity of butadiene and butanone is lowered. In addition, it can be seen that the selectivity of butadiene and butanone is greatly reduced when the feed rate (LHSV) of the reactant 2,3-butanediol is outside the range of 0.3 to 1.5 h ⁻¹ .

When the calcium phosphate component or reaction condition is out of the scope of the present invention from the results of the above examples and comparative examples, 2,3-butanediol is continuously dehydrated to prepare 1,3-butadiene and 2-butanone in high yield. It can be seen that it is possible to produce 2,3-butanediol and 2-butanone in high yield by continuously dehydrating 2,3-butanediol by the catalyst and reaction method according to the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Those skilled in the art will recognize that many modifications and variations are possible in light of the above teachings.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (11)

A process for preparing 1,3-butadiene from 2,3-butanediol in the presence of a catalyst selected from hydroxyapatite, calcium pyrophosphate, or mixtures thereof. A process for preparing 2-butanone from 2,3-butanediol in the presence of a catalyst selected from hydroxyapatite, calcium pyrophosphate, or mixtures thereof. 3. The method according to claim 1 or 2,
The dehydration reaction of 2,3-butanediol is carried out under the conditions of reaction temperature of 340 to 450 ℃, reaction pressure of 1 to 6 atm and 2,3-butanediol liquid space velocity (LHSV) of 0.3 to 1.5 h ^-1 . A catalyst for producing 1,3-butadiene and 2-butanone from 2,3-butanediol, wherein the catalyst is selected from hydroxyapatite, calcium pyrophosphate, or mixtures thereof. In a method for producing a high functional catalyst for producing 1,3-butadiene and 2-butanone from 2,3-butanediol,
(a) mixing an alkali salt with an aqueous solution containing phosphoric acid to prepare an aqueous phosphate solution;
(b) preparing a calcium phosphate salt by mixing and stirring the aqueous solution of calcium precursor to the aqueous solution of phosphate; And
(c) Calcium Phosphate Salt was prepared by heat treatment at 300 to 700 ° C. in air to form hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)), calcium pyrophosphate (Ca ₂ (P ₂ O ₇ )) or their Preparing a catalyst that is a mixture;
Method for producing a high functional catalyst comprising a. 6. The method of claim 5,
PH of the aqueous solution of phosphate of step (a) is 10.0 to 12.0 method of producing a high functional catalyst. 6. The method of claim 5,
Stirring the step (b) is a method for producing a high functional catalyst is carried out at 60 to 90 ℃. 6. The method of claim 5,
The phosphoric acid of step (a) is orthophosphoric acid (H ₃ PO ₄ ), pyrophosphoric acid (H ₄ P ₂ O ₇ ), tripolyphosphoric acid (H ₅ P ₃ O ₁₀ ) and tetrapolyphosphoric acid (H ₆ P ₄ O ₁₃ ) Method for producing a high functional catalyst at least one selected from. 6. The method of claim 5,
The phosphoric acid concentration of the aqueous solution of phosphate in step (b) is 0.1 to 0.4 normal, the calcium concentration of the calcium precursor aqueous solution is 1.0 to 4.0 normal, and the calcium precursor aqueous solution is mixed so that the molar ratio of phosphoric acid: calcium is 1: 0.7 to 1.5. Method for producing a high functional catalyst. The method of claim 9,
The calcium precursor aqueous solution is a method for producing a high functional catalyst is dripping in the aqueous solution of phosphate at a rate of 3 to 10ml / min. 6. The method of claim 5,
The preparation method is after step (b) and before step (c),
(b2) recovering the dried calcium phosphate salt and pulverizing to a size of 5 to 100 μm; And
(b3) forming the pulverized calcium phosphate salt into pellets;
Method for producing a high functional catalyst further comprising.

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