JP4110241B2 - Carbon monoxide conversion catalyst and carbon monoxide conversion method using the catalyst - Google Patents

Description

[比較例１]
３１.７gの硝酸銅三水和物、３８.１gの硝酸亜鉛六水和物、１５.３gの硝酸アルミニウム九水和物を蒸留水に溶解し３００mlとした溶液Ａと、８７.４gの無水炭酸ナトリウムを蒸留水に溶解し３００mlとした溶液Ｂを、４００gの蒸留水中に、毎分７mlの速度で滴下して沈殿物を得た。
【００３８】
得られた沈殿物は、３日間熟成させ、濾過、洗浄後、１１０℃で一昼夜乾燥した。乾燥後の沈殿物は、６００℃で３時間空気中で焼成して、触媒とした。
この触媒の組成は重量基準で、酸化銅４６.１%、酸化亜鉛４４.７%、酸化アルミニウム９.３%であった。
【００３９】
得られた触媒を用いて、実施例１と同様にして一酸化炭素の水蒸気による転化反応を行った。
反応生成ガスをガスクロマトグラフにより分析し、一酸化炭素転化率を調べた。結果を表２に示す。
【００４０】
[比較例２]
３５.１gの硝酸銅三水和物、２５.３gの硝酸亜鉛六水和物、１２.５gのオキシ硝酸ジルコニウム、８.５gの硝酸アルミニウム九水和物を蒸留水に溶解し３００mlとした溶液Ａと、３６.３gの無水炭酸ナトリウムを蒸留水に溶解し３００mlとした溶液Ｂを、４００gの蒸留水中に毎分７mlの速度で滴下して沈殿物を得た。得られた沈殿物は、３日間熟成させ、濾過、洗浄後、１１０℃で一昼夜乾燥した。乾燥後の沈殿物は、６００℃で３時間空気中で焼成して、触媒とした。
この触媒の組成は重量基準で、酸化銅４６.８%、酸化亜鉛２６.９%、酸化ジルコニウム２１.６%、酸化アルミニウム４.７%であった。
【００４１】
得られた触媒を用いて、実施例１と同様にして、一酸化炭素の水蒸気による転化反応を行った。
反応生成ガスをガスクロマトグラフにより分析し、一酸化炭素転化率を調べた。結果を表２に示す。
【００４２】
【表２】

表１および表２に示す通り、本発明の触媒により、一酸化炭素の水蒸気による転化反応において、高い一酸化炭素転化効率を長時間に亘って得られることは明らかである。
【００４３】
【発明の効果】
本発明によって、１５０〜３００℃の比較的低い温度範囲において、極めて高い一酸化炭素の転化効率を長時間に亘って保持することのできる、高活性で高耐久の優れた酸化銅-酸化亜鉛系の一酸化炭素低温転化反応用触媒、および該触媒 を用いる一酸化炭素転化方法が提供され、触媒、用役、原料各原単位が向上する等の産業上有用な効果が奏される。[0001]
[Technical field to which the invention belongs]
The present invention relates to a catalyst for carbon monoxide reaction used in a reaction called carbon monoxide conversion reaction for generating hydrogen and carbon dioxide from carbon monoxide and water vapor, or a water gas shift reaction, and more specifically, carbon monoxide. Among the conversion catalysts, the present invention relates to a copper oxide-zinc oxide based carbon monoxide low temperature conversion reaction catalyst used at a relatively low temperature of about 150 to 300 ° C., and a carbon monoxide low temperature conversion method using the low temperature conversion catalyst. .
[0002]
[Prior art]
Carbon monoxide conversion catalysts used at a relatively low reaction temperature of 150 to 300 ° C. are important catalysts that have been used industrially for a long time, and copper oxide-zinc oxide catalysts have been used to date. Its representative and important catalyst.
Conventional copper oxide-zinc oxide-based catalysts have various problems that cannot be ignored, such as being easily poisoned by catalyst poisons such as sulfur and chlorine, and causing a decrease in activity due to the influence of high temperature or excessive water vapor.
[0003]
In order to solve these problems, addition of components such as chromium oxide, manganese oxide, and aluminum oxide has been studied and put into practical use. Forty years ago, a copper oxide-zinc oxide-aluminum oxide catalyst was put into practical use, and remarkable progress was made in solving the durability problem. Since then, this kind of catalyst has been used as a low-temperature conversion catalyst for more than 30 years. Used exclusively today.
[0004]
However, even with the practical use of this type of catalyst, it is difficult to say that the problem of low durability of the copper oxide-zinc oxide based catalyst has been completely solved. The situation is that the situation in which it is necessary to replace the deteriorated catalyst has not been avoided.
[0005]
Japanese Patent Laid-Open No. 64-27645 discloses that a copper surface area suitable for a carbon oxide conversion process (carbon monoxide conversion reaction, methanol synthesis reaction, etc.) comprising metallic copper and zinc oxide and / or magnesium oxide is at least 70 m 2 / s. A catalyst that is gCu is disclosed.
[0006]
As an optional component of this catalyst, an element X selected from Al, V, Cr, Ti, Zr, Tl, U, Mo, W, Mn, Si and a rare earth is shown, and the content of X is an essential component. It is shown to be 2 to 50% based on the total amount of copper, zinc, magnesium and X.
It has also been shown that the calcination temperature of this catalyst exceeds 250 ° C. (300-350 ° C.) and the reduction temperature to metallic copper is preferably less than 200 ° C.
[0007]
However, no specific example of a catalyst containing silicon oxide is shown, and no specific amount of silicon oxide is described. Further, there is no mention of high durability and long-term stability of the catalyst.
[0008]
In addition, one of the present inventors has proposed a copper-based catalyst containing a small amount of silicon oxide for methanol synthesis reaction in Japanese Patent Application No. 9-294097, but the silicon oxide content suitable for methanol synthesis is It is limited to the range of 0.3 to 0.9% by weight.
However, it relates to a different catalyst that targets a different reaction from the present invention and specifies a different silicon oxide content.
[0009]
[Problems to be solved by the invention]
In order to stably operate for a long period of time without exchanging the catalyst, it is required to develop a catalyst having high activity and excellent durability that does not cause a decrease in activity.
[0010]
The present invention has been made in view of such problems, and the object of the present invention is to have a high durability used for the conversion reaction of carbon monoxide without the above-mentioned problems and a high durability without a decrease in the activity. The object is to provide a copper oxide-zinc oxide based catalyst (catalyst for carbon monoxide low temperature conversion reaction) having excellent long-term stability, and a carbon monoxide low temperature conversion method using the low temperature conversion catalyst.
[0011]
[Means for Solving the Problems]
In order to solve these problems, the present inventors have conducted extensive studies on a copper oxide-zinc oxide catalyst for conversion reaction of carbon monoxide. As a result, a specific amount of oxidation was added to the conventional copper oxide-zinc oxide catalyst. It has been found that a catalyst to which silicon has been added has extremely high activity in the carbon monoxide conversion reaction, does not cause a decrease in activity during use, and maintains high activity over a long period of time. It was.
[0012]
That is, the present invention comprises high oxide containing, in addition to copper oxide and zinc oxide, silicon oxide in an amount in the range of 0.5-5% by weight of the total catalyst weight, or aluminum oxide in an amount in the range of 1-30%. The present invention discloses a catalyst for low-temperature carbon monoxide conversion reaction that is active and has high durability and excellent long-term stability, and a low-temperature carbon monoxide conversion method using the low-temperature conversion catalyst.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described, but the present invention is not limited thereto.
[0014]
The contents of copper oxide and zinc oxide, which are active components of the catalyst, are preferably in the range of 20 to 65% by weight and 10 to 70% by weight, respectively. If the content is outside this range, the activity or durability of the catalyst is not sufficiently exhibited.
The catalyst of the present invention may contain aluminum oxide and other components. In particular, when 1 to 30% by weight of aluminum oxide is contained, the catalyst has good effects on moldability, activity and durability.
[0015]
A feature of the catalyst of the present invention is that a specific amount of silicon oxide is added to a conventional copper oxide-zinc oxide catalyst, and the addition amount is preferably 0.5 to 5% by weight. More preferably, it is made into 5 weight%.
When the content is lower than 0.5% by weight, the effect of improving the catalyst durability is small, and even when the content is 0.5% by weight or more, if the content is less than 1% by weight, the effect of improving the durability is sufficient in some cases. May not be expressed. Further, when the content exceeds 5% by weight, the activity decreases.
[0016]
The effect of adding the silicon component to the catalyst is closely related to the partial pressure of water vapor during the reaction, and the partial pressure of water vapor in the carbon monoxide conversion reaction is much higher than in the case of the methanol synthesis reaction described above.
Furthermore, carbon monoxide conversion catalysts and methanol synthesis catalysts generally contain both copper oxide and zinc oxide, but it is known that the surface sites involved in both of the above reactions of this catalyst are different. It has been.
[0017]
The catalyst of the present invention has been intensively studied in consideration of the above points, and the carbon monoxide conversion catalyst has a higher content of silicon component than the catalyst for methanol synthesis, and a specific content of silicon component is extremely effective. It was obtained on the basis of the results of finding that.
[0018]
The method for producing the catalyst of the present invention is not particularly different from the currently well-known method for producing a catalyst for carbon monoxide conversion reaction based on copper oxide-zinc oxide, except that a silicon component addition step is added. Various current manufacturing methods can be applied.
The composition is preferably calcined in the range of 350 to 650 ° C. in the production of the present catalyst. If this calcining step is omitted, ensuring of catalyst durability is significantly hindered, which is not desirable.
[0019]
Colloidal silica is most preferable as a raw material used when adding the silicon component, but is not limited to colloidal silica, and dissolved silica, oxalic acid, various oxalates, and the like can also be used.
The timing of adding the silicon component may be at any stage of the catalyst production, but it is necessary that the silicon component is well dispersed. For this purpose, the addition of the active component in the precipitation step is most desirable.
[0020]
The shape, size, etc. of the catalyst are appropriately selected according to the purpose of use and are not particularly limited.
[0021]
Prior to use, the catalyst of the present invention needs to reduce copper oxide to metallic copper. However, the reduction operation may be performed outside the reactor and then charged into the reactor, or the catalyst may be loaded into the reactor. After filling, reduction may be performed using carbon monoxide, hydrogen, or the like contained in the reaction gas. The reduction temperature is suitably 200 to 350 ° C.
[0022]
【Example】
Hereinafter, the present invention will be described in detail by way of examples, and the features of the present invention will be clarified more clearly.
[0023]
[Example 1]
31.7 g copper nitrate trihydrate, 38.1 g zinc nitrate hexahydrate, 15.3 g aluminum nitrate nonahydrate and 1 g collodal silica (Snowtex O, Nissan Chemical Industries, silica concentration 20 weight) %) Was dissolved in distilled water to 300 ml, and 37.4 g of anhydrous sodium carbonate in 300 ml of distilled water was added dropwise to 400 g of distilled water at a rate of 7 ml per minute. A precipitate was obtained.
[0024]
The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The dried precipitate was calcined in the air at 400 ° C. for 3 hours to form a catalyst.
The composition of this catalyst was, on a weight basis, 45.8% copper oxide, 44.2% zinc oxide, 9.3% aluminum oxide and 0.7% silica.
[0025]
0.5 ml of the catalyst obtained was filled into a reaction tube, a mixed gas of helium and hydrogen (90% by volume of helium, 10% by volume of hydrogen) was supplied at a flow rate of 300 ml / min, and the copper oxide in the catalyst at 300 ° C. Hydrogen reduction was performed.
After the reduction of the catalyst, a raw material gas (volume basis CO: 3%, CO ₂ : 17%, hydrogen: 80%) and water vapor were supplied to the reaction tube to carry out a conversion reaction.
[0026]
The reaction conditions were a temperature of 205 ° C., a pressure of 11 kg / cm 2 G, a volume ratio of water vapor to the raw material gas of 1.5, and a space velocity of the raw material gas (excluding water vapor) was 11.250 (h −1).
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 1.
[0027]
[Example 2]
31.7 g copper nitrate trihydrate, 38.1 g zinc nitrate hexahydrate, 15.3 g aluminum nitrate nonahydrate and 1.5 g collodal silica (Snowtex O, Nissan Chemical Industries, silica concentration) 20% by weight) dissolved in distilled water to 300 ml, and 37.4 g of anhydrous sodium carbonate dissolved in distilled water to 300 ml of solution B were dropped into 400 g of distilled water at a rate of 7 ml per minute. To obtain a precipitate.
[0028]
The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The precipitate after drying was calcined in air at 500 ° C. for 3 hours to obtain a catalyst.
The composition of the catalyst was 45.6% copper oxide, 44.1% zinc oxide, 9.3% aluminum oxide and 1.0% silica on a weight basis.
[0029]
Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 1.
[0030]
[Example 3]
The same precipitate as prepared in Example 2 was calcined in air at 600 ° C. for 3 hours to form a catalyst. Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 1.
[0031]
[Example 4]
31.7 g copper nitrate trihydrate, 38.1 g zinc nitrate hexahydrate, 15.3 g aluminum nitrate nonahydrate and 3 g collodal silica (Snowtex O, Nissan Chemical Industries, silica concentration 20 weight) %) Was dissolved in distilled water to 300 ml, and 37.4 g of anhydrous sodium carbonate in 300 ml of distilled water was added dropwise to 400 g of distilled water at a rate of 7 ml per minute. A precipitate was obtained.
[0032]
The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The dried precipitate was calcined in the air at 400 ° C. for 3 hours to form a catalyst.
The composition of this catalyst was, on a weight basis, 45.3% copper oxide, 43.7% zinc oxide, 9.2% aluminum oxide and 1.9% silica.
[0033]
Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 1.
[0034]
[Example 5]
31.7 g of copper nitrate trihydrate, 38.1 g of zinc nitrate hexahydrate, 15.3 g of aluminum nitrate nonahydrate and 5 g of collodal silica (Snowtex O, Nissan Chemical Industries, silica concentration 20 wt. %) Was dissolved in distilled water to 300 ml, and 37.4 g of anhydrous sodium carbonate in 300 ml of distilled water was added dropwise to 400 g of distilled water at a rate of 7 ml per minute. A precipitate was obtained.
[0035]
The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The dried precipitate was calcined in the air at 400 ° C. for 3 hours to form a catalyst.
The composition of the catalyst was 44.7% copper oxide, 43.2% zinc oxide, 9.1% aluminum oxide and 3.1% silica on a weight basis.
[0036]
Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 1.
[0037]
[Table 1]

[Comparative Example 1]
31.7 g of copper nitrate trihydrate, 38.1 g of zinc nitrate hexahydrate, 15.3 g of aluminum nitrate nonahydrate dissolved in distilled water to 300 ml, and 87.4 g of anhydrous A solution B obtained by dissolving sodium carbonate in distilled water to 300 ml was dropped into 400 g of distilled water at a rate of 7 ml per minute to obtain a precipitate.
[0038]
The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The precipitate after drying was calcined in air at 600 ° C. for 3 hours to obtain a catalyst.
The composition of this catalyst was 46.1% copper oxide, 44.7% zinc oxide, and 9.3% aluminum oxide on a weight basis.
[0039]
Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 2.
[0040]
[Comparative Example 2]
A solution prepared by dissolving 35.1 g of copper nitrate trihydrate, 25.3 g of zinc nitrate hexahydrate, 12.5 g of zirconium oxynitrate and 8.5 g of aluminum nitrate nonahydrate in distilled water to make 300 ml. A and a solution B in which 36.3 g of anhydrous sodium carbonate was dissolved in distilled water to make 300 ml were dropped into 400 g of distilled water at a rate of 7 ml / min to obtain a precipitate. The obtained precipitate was aged for 3 days, filtered, washed, and dried at 110 ° C. overnight. The precipitate after drying was calcined in air at 600 ° C. for 3 hours to obtain a catalyst.
The composition of this catalyst was 46.8% copper oxide, 26.9% zinc oxide, 21.6% zirconium oxide, and 4.7% aluminum oxide on a weight basis.
[0041]
Using the obtained catalyst, the conversion reaction of carbon monoxide with water vapor was carried out in the same manner as in Example 1.
The reaction product gas was analyzed by gas chromatograph, and the carbon monoxide conversion was examined. The results are shown in Table 2.
[0042]
[Table 2]

As shown in Tables 1 and 2, it is clear that high conversion efficiency of carbon monoxide can be obtained for a long time in the conversion reaction of carbon monoxide with water vapor by the catalyst of the present invention.
[0043]
【The invention's effect】
According to the present invention, a highly active and highly durable copper oxide-zinc oxide system capable of maintaining a very high carbon monoxide conversion efficiency over a long period of time in a relatively low temperature range of 150 to 300 ° C. A carbon monoxide low temperature conversion reaction catalyst and a carbon monoxide conversion method using the catalyst are provided, and industrially useful effects such as improvement of the catalyst, utility, and raw material basic units can be achieved.

Claims (5)

In the carbon monoxide conversion catalyst, a composition containing 20 to 65% of copper oxide, 10 to 70% of zinc oxide and 0.5 to 5% of silicon oxide as active components in a weight basis percentage with respect to the total weight of the catalyst. A catalyst for low-temperature carbon monoxide conversion reaction, characterized by firing a product. The catalyst for low-temperature carbon monoxide conversion reaction according to claim 1, which contains the silicon oxide in a range of 1 to 5%. The catalyst for low-temperature carbon monoxide conversion reaction according to claim 1 or 2, wherein the active ingredient further contains aluminum oxide in an amount of 1 to 30%. The catalyst for low-temperature carbon monoxide conversion reaction according to claim 1, 2 or 3, wherein the calcination temperature of the composition is in the range of 350 to 650 ° C. The carbon monoxide conversion method, wherein the catalyst used in the method is a carbon monoxide low temperature conversion reaction catalyst according to any one of claims 1 to 4.