DD145094A5 - METHANOL FOR THE PREPARATION OF METHANOL - Google Patents

Description

The invention relates to a process for the preparation of methanol by catalytic synthesis of carbon monoxide and carbon dioxide with hydrogen.

Characteristic Eristik d he "bek annten technical solutions

Methods are known in which the hydrogenation of carbon monoxide and carbon dioxide proceeds in a recirculation system. In this case, a gas mixture consisting of hydrogen, carbon monoxide and carbon dioxide, at a temperature of 200 to 300 ⁰ C and at an elevated '-'ruck 30 to at via a catalyst layer, in particular a copper-zinc-aluminum catalyst, passed «The reaction gases are cooled, and the resulting after gas liquefaction in the separator liquid products are removed. Once the components are passed through the catalyst, no full hydrogenation takes place. After separation of the methanol, the unreacted gas is supplemented with a fresh gas and returned to the synthesis reactor. During the preparation of the methanol, the precise regulation of the temperature in the catalyst bed is necessary because the temperature has a significant influence on the yield and on the amount of byproducts formed. The hydrogenation reaction is highly exothermic. As the reaction is passed over the catalyst, the temperature increases gradually, gradually

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Also increase, the partial pressures of the components that take no part in the reaction.

The commonly used catalysts containing zinc chromate are sufficiently active at temperatures above 300 ⁰ C, so that the reaction between carbon monoxide, carbon dioxide and hydrogen proceeds sufficiently fast. However, the state of thermodynamic equilibrium is so unfavorable at these temperatures that this equilibrium can only be achieved at pressures above 200 at.

The catalysts, which also contain copper in addition to zinc and chromium, catalyze the synthesis of methanol at temperatures of 200 to 300 ⁰ G so that the process can be carried out at pressures of 50 to 100 at. However, these catalysts have disadvantages because they can be used only in a narrow temperature range, and the life of these catalysts does not exceed 10,000 hours. Although it is possible to choose the reaction conditions such as temperature, pressure, gas composition and load so that the yield of methanol is above T kilograms per 1 liter per 1 hour, but then the Y / poor development is so large that the aging of the copper catalysts is accelerated , In this case, there is a non-reversible recrystallization of this component, which causes a significant reduction in the life and the activity of the copper catalysts. -

Object of the invention '..

The aim of the invention is to provide a method

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For the production of methanol, in which the technical parameters such as pressure and temperature for maintaining the activity of the catalyst can be reduced over a long period of time and the yield of methanol per catalyst unit is increased.

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the essence of the invention

The invention has for its object to find a suitable catalyst composition.

It was found that the methanol synthesis at a pressure of 50 to 110 at, at temperatures of 160 to 300 ⁰ C and at volume velocities of 5000 to

-1

50,000 h, if according to the invention applies catalysts containing copper, zinc and aluminum or copper, zinc and chromium and additionally manganese, wherein the amounts of the individual oxides, in terms of weight percentages be: from 20 to 50 % copper -οχίά, from 15 to 60 % zinc oxide, from 5 to 35 % alumina, from 5 to 35 % chromium oxide, from 0.2 to 7 % manganese oxide.

According to the invention, the synthesis gas, which is from 60 to 80 % H ₂ , from 5 to 25 % CO, from 3 to 10 % CO ₂ , up to 5 % CH ₄ , up to 15 % N ₂ , preferably 71 % H ₂ , 18 , 5 % CO / 5.5 % CO ₂ , 2 % CH-, 3 % N ₂ , passed over a copper catalyst, the temperature being gradually increased from 140 to 180 C / the pressure up to 30 at and the volume space velocity of the gas until to 10 000 ml / l ^. h be increased. In this case, the active form of the copper catalyst is obtained.

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The rate of reduction is determined according to the precipitated water and the temperature in the catalyst zone. After determination of the claimed working parameters of the catalyst, the mixture is applied to the catalyst bed, consisting of copper, zinc, aluminum and manganese or of copper, zinc, chromium and manganese under a pressure of 30 to 110 at a temperature of 160 to 300 ⁰ C and

-1 at a volume space velocity of 5000 to 50,000 h

dosed.

The activity of the catalysts, measured at appropriate time intervals and expressed in kilograms of 100% methanol per 1 kg of the catalyst and per 1 hour, was determined in Tables 1 and 2 20 to 50 wt -.% copper oxide, from 15 to 60 wt .-% of zinc oxide, from 5 to 35 wt .-% aluminum oxide, from 5 to 35 wt £ chromium oxide and from 0.2 to 7 wt .-% manganese contains, is of copper, zinc, aluminum, ^u hrom- and manganese nitrate solutions through with precipitation of at least two components at elevated temperature prepared using sodium carbonate or sodium hydroxide, v / obei the temperatures of the nitrate solution and the precipitant are identical and from 80 to 100 ⁰ C amount. The filling concentration of 5 to 10 wt .-% and the Ixtratiösung of 10 to 15 wt .-%, calculated on the sum of! Titrate. The final pH is between 8 and 9. except neutral Rea3rtion washed precipitate is dried at a temperature of 270-300 ⁰ C and granulated with an addition of 2% graphite. Then in the catalytic system manganese in the form of an aqueous Permangansäurelösung with a concentration of 2 to 4 % by weight or an aqueous

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Manganese acetate solution with a concentration of 2 to 10 % , and then the whole dried and tableted

The Dosierungsgescligeschwindigkeit the Mllungslösung during the filling of the catalyst is from 30 to 50 l / h.

According to the invention, the production process of methanol can be carried out in one stage with a gas circulation after the liquefaction and separation of the liquid product or in many stages with interim separation of the methanol ».

When applying the erfindungsgeniäß en method, the yield of methanol is increased. According to the "process according to the state of the art, from 0.35 to 0.60 kg of 100% methanol per 1 kg of catalyst and per hour are obtained, whereas 0.9 kg of methanol per 1 kg are obtained by the process according to the invention Catalyst and per 1 hour The use of a catalyst containing copper, zinc, aluminum and manganese or copper, zinc, chromium and manganese, in a visible way, allows to improve the reaction parameters, namely to lower the pressure and the temperature The life of the catalyst when using the production process of methanol according to the invention is two years.

The crude ethanol obtained by the process according to the invention contains up to 1 Gev /% of organic compounds, such as high molecular weight alcohols, ethers and paraffin.

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carbons "existing impurities.

embodiment

The invention will be explained in more detail below on some embodiments.

example 1

The reactor having a diameter of 16 mm and a height vcn were ran 600 100 g catalyst 32.4 wt .-% of CuO, 44.3 wt .-% ZnO, 22,3 G _e w .-% Al ₂ OJ and 1 G _e w .- ^ MnO ₂ contains supplied. About this catalyst was a gas mixture, which 71 % H ₂ , 18.5 % CO ₉ 5.5 % CO ₂ , 2 % CH. and

Contains 3.0 % N ₀ , with a volume velocity of 1 ''

The temperature was increased gradually from 140 to 180 ^° C. and the bridge to 30 ° in order to obtain an active form of the catalyst, followed by the same mixture under a pressure of 50 at Temperature of 180 ⁰ C and metered at a volume rate of 20 000 Nl / 1 cat. Χ hour. The crude methanol obtained contained 90.0 % CH-, OH, 9.2 % H ^ O and 0.8 % organic compounds, predominantly methyl formate, acetone, ethanol and high molecular weight alcohols.

Tables 1 and 2 give the results of the activity of different catalysts. It is expressed in kilograms of 100% methanol per 1 kg of catalyst and per hour in certain technological parameters.

Table 1,

T = 180 ⁰ C, ρ = 50 atm, ν = 20 000 h ^{"Gaszusaramensetzung:} 67.2% E _ot 22.5% CO, 5.5% CO _2, 1.9% CH _4, 2.5% H ₂

Catalyst

CuO - 32.4 ZnO - 44.3 Al ₂ O ₃ - 22.3 - 1.0

CuO - 30.3 ZnO - 44.3 Al ₂ O ₃ - 20.4 MnO- 5.1

Operating time (left)

50 100 200 300

kg 100 % CBLOH / kg Cat. H

0.900 0.920 0.900 0.920 0.930 Manganese was introduced into the catalytic system in the form of HMnO during granulation.

0.600 0.800 0.800 0.885 0.795 Manganese was introduced into the catalytic system during precipitation from the Cu, Zn, Al and Mn-Uitral solutions.

CuO - 25.0 ZnO - 50.0 Al ₂ O ₃ - 23.0 Mn; - 2.0

CuO ZnO

CrPO.,

MnO *

40.0 38.0 - 20.0 2.0

0.930 0.950 0.960 0.945 0.960 Manganese was introduced into the catalytic system in the form of manganese acetate during granulation

0.750 0.800 0.885 0.800 0.795 Manganese was introduced into the catalytic system in the form of manganese acetate during granulation.

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Table 2. T «200 ⁰ O, ρ« 70 atm, ν - 20 000 h ~ ¹

Gas composition / 67.2 % H ₀₁ 22.5 % CO, 5.5% GO ₂ , 1.9 ^ CH ₄ , 2.5% H

Catalyst (wt .-% S)

Operating time (h)

50 100 200 300

kg 100 % CtuOH / kg cat. h Remarks

CuO - 32.4 ZnO- 44.3 Al ₂ O ₃ - 22.3 'MnOp. .- 1.0

1,800 1,150 1,100 1,250 1,200 manganese was introduced into daa catalytic system in the form of FEInO ₄ during granulation.

30.3 44.3 - 20.4

5.1

CuO - 25.0 ZnO - 50.0 AIpOo - 23.0 Mn - ^ 2.0

CuO - 40.0 ZnO - 38.0 Cr ₀ Oo - 20.0

Τ ,, Τν ^ ίΛ J. O Γ \

0.800 0.850 0.910 0.905 0.910 Manganese was introduced into the catalytic system during precipitation from the Cu, Zn, Al and Mn nitrate solutions.

0.950 1.170 1.205 1.1880 1.200 Manganese was introduced into the catalytic system in the form of manganese acetate during granulation.

0.850 0.900 0.905 0.900 0.895 manganese was introduced into the catalytic system in the form of manganese acetate during granulation.

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Claims (3)

invention claim 1 «Process for the preparation of methanol from a carbon monoxide, carbon dioxide and hydrogen-containing synthesis gas, characterized in that the synthesis gas at a pressure of 40 to 110 at an 'i' temperature of 160 to 300 ⁰ C via a catalyst consisting from 20 to 50% by weight of copper oxide, 15 to 60% by weight of zinc oxide, 5 to 35% by weight of aluminum oxide and 0.2 to 7% by weight of manganese oxide, " 2. A process for the preparation of methanol from a carbon monoxide, carbon dioxide and hydrogen-containing synthesis gas according to item 1, characterized in that the synthesis gas at a pressure of 40 to 110 at and at a temperature of 160 to 300 ⁰ C via a catalyst consisting of 20 to 50 weight percent copper oxide, 15 to 60 weight percent sink oxide, 5 to 35 weight percent chromium oxide, and 0.2 to 7 weight percent manganese oxide. 3 »A process for producing methanol iaach point 1, 2, characterized in that a synthesis gas is employed, the 60 to 80% H _0, of 5 to 25% CO, 3-10 fo CO _9, to 5% CH ,,, contains up to 15%%. C. ·? C.,