DE2644107C2 - Process for the oxydehydrogenation of ethane to produce ethylene and acetic acid - Google Patents

Description

Mo ₁₁ X ₄ Y, where X stands for V and Nb, Y stands for Bi, Ce, Co, Cu, Fe, K, Mg, Ni, Pb, Sb, Sn, Tl and / or U;

a = l

b = 0.05 to 2 and

c = 0 to 1,

with the proviso that the total value of c for Fe, Co and / or Ni is less than 0.5.

2 The method according to claim 1, characterized in that it is in the presence of added water is carried out.

The present invention relates to the gas phase catalytic dehydrogenation of ethane in ethylene In Presence of oxygen, d. H. on the oxydehydrogenation of ethane in ethylene.

On an industrial scale, ethylene was usually produced by thermal cracking of ethane in an endothermic reaction at temperatures of about 600-1000 ° C. (cf. US Pat. No. 3,541,179) Process is very short, making effective heat recovery from the process stream difficult or difficult makes impossible. Furthermore, the high temperatures used require the use of special alloys in the construction of the furnaces or reaction vessels for carrying out the reaction. The cracking reaction also causes the formation of relatively large amounts of low-boiling by-products such as hydrogen and methane, which makes the recovery of ethylene from these by-products complicated and costly.

It is possible to oxydehydrogenate ethane using various oxyhalogenation catalyst systems in an exothermic reaclone. However, these reactions have only been carried out at temperatures of at least about 500-600 ° C. (see US Pat. No. 3,080,435). Furthermore, the presence of the halogen atoms increases the difficulty of recovering all of the olefins formed. In addition, unusual and expensive construction materials that resist corrosion are necessary. Furthermore, the halogens themselves must also be recovered and recycled in order to make the system economical.

Also processes for the oxydehydrogenation of aliphatic hydrocarbons by means of oxygen Use of transition metal catalysts are already known. The catalysts used there

contain e.g. B. Vanadium (see. US-PS 32 18 368, 35 41 179 and 38 56 881 and GB-PS 946 583), molybdenum and magnesium (DE-OS 22 37 682), molybdenum and cobalt or nickel (DE-OS 18 16 847), molybdenum or

Tungsten (DE-OS 18 00 063) or molybdenum and / or vanadium (US-PS 33 20 331) as essential components. What all these processes have in common, however, is that, as the examples show, significant yields and Selectivities can only be achieved when the reaction temperature significantly exceeds 400 ° C, whereby this In particular it seems to apply to the oxydehydrogenation of ethane.

So it has not been possible until now. Ethane easily at relatively low temperatures with relatively high Values for conversion, selectivity and productivity to oxydehydrogenate to ethylene.

The terms "percentage conversion", "percentage selectivity" and "production vital" used here are defined as follows with reference to the present invention:

I% conversion _. _{nn χ} A

(of ethane) _Mo ( _E , _{han) in the} reaction mixture fed to the catalyst bed

. "Ia where A = molar ethane equivalent sum (carbon basis) of all carbon-containing products excluding ethane in the effluent

100 x

moles of ethylene (or acetic acid) produced

II% selectivity (or effectiveness) for ethylene

(or acetic acid)

III Productivity for ethylene _ kg of ethylene (or acetic acid) produced per m ^{3 of} catalyst (in the catalyst (or acetic acid) bed) per hour of reaction time

The aim of the present invention is to provide a process for the oxydehydrogenation of ethane for Production of ethylene at relatively low temperatures with relatively high levels of conversion, selectivity and productivity. Another goal is to create a process for the oxydehydrogenation of ethane

in the presence of water at relatively low temperatures and with relatively high conversion, selectivity and productivity in terms of the products ethylene and acetic acid.

The present invention is characterized by the above claims. The numerical values of a. b and £ · represent the relative gram atomic ratios of the elements Mo, X and Y, which are present in the catalyst preparation. ; ■

In the process according to the invention, ethane can be used without the simultaneous formation of substantial amounts of gaseous By-products, such as methane and hydrogen, that cause the cryogenic separation and purification of the ethylene difficult and costly to be oxydehydrogenated to ethylene.

The elements Mo, X and Y are in the catalyst preparation in combination with oxygen, presumably in the form various oxides per se and possibly present as chemical combinations of oxides.

The catalyst is preferably prepared from a solution of soluble compounds (salts, complexes or other compounds) of each of the elements Mo, Y and X or, in the case of Sb, also as a colloidal sol. The solution is preferably an aqueous system with a pH of 1-7, preferably 2-6. The solution of the element-containing compounds is prepared by dissolving sufficient amounts of the soluble compounds of each element to create the desired a: b: c gram atom ratio of the elements Mo, X and Y, respectively. The selected compounds of the various elements should be mutually soluble as much as possible. Where the selected compounds of the elements are not soluble with the other compounds, they can be added last to the solution system. The catalyst preparation is then produced by removing water or other solvent from the mixture of compounds in the solution system.

Water or other solvents can be obtained by evaporation of the combination of all compounds and Solvent obtained mixture are removed.

Where the catalyst is to be used on a carrier, the compounds of the desired elements are deposited on a finely divided porous carrier, which should have the following physical properties, among other things: spec. Surface area = about 0.1-500 mVg; apparent porosity = 30-60 "; wherein at least 90% of the pores have a pore diameter between 20-1500 μm and dte particles or tablets have a diameter of about 3.2-8.0 mm. The deposition is carried out by immersing the support in the final mixture of all compounds, evaporating the substantial portion of solvent and then drying the system at 80-220 ⁰ C for 2-60 hours. The dried catalyst is then calcined by heating at about 220-550 ° C. for 0.5-24 hours in air or oxygen and provides the desired

Preparation.

Usable carriers include silica, alumina, silicon carbide, zinc alumina, titania and theirs Mixtures.

When used on a carrier, the deposited catalyst will usually comprise about 10-50% by weight Catalyst preparation, the remainder being the carrier.

The molybdenum is preferably in the solution in the form of ammonium salts, such as ammonium paramolybdate, and organic acid salts of molybdenum, e.g. B. as acetate, oxalate, mandelate or glycolate introduced. Other suitable, water-soluble molybdenum compounds are partially water-soluble molybdenum oxides, molybdic acid and the chlorides of molybdenum.

Vanadium is preferably used in the form of its ammonium salts, such as ammonium metavanadate and ammonium deeavanadate, and organic acid salts of vanadium such as the acetates, oxalates and tartrates. in the Solution introduced. Other suitable water-soluble vanadium compounds are, in part, water-soluble vanadium lumoxides and the sulfates of vanadium.

Niobium is preferably introduced into the solution in the form of the oxalate. Other suitable sources of this Metals in soluble form are compounds in which the metal is attached to a ß-Dlketonat, a carboxylic acid AmIn, an alcohol or an alkanolamine is coordinated, bound or bound in complex form.

When using iron, nickel, cobalt, copper, bismuth, uranium, cerium, potassium, thallium, magnesium and For lead, these are preferably introduced into the solution in the form of the NIS rate. Other suitable water soluble Compounds of these elements are the water-soluble chlorides and organic acid salts, such as the acetates, Oxalates, tartrates, lactates, salicylates, formlates and carbonates of these elements.

When using antimony and tin, these are preferably in the form of water-insoluble oxides Kaialvsatorystem introduced. Suitable water-soluble compounds of these elements are Antlmontrlchlorid, SndDchlorld, Sn (IV) chlorld, Sn (II) sulfate and Sn (IV) suIfat. Other suitable water-insoluble compounds of these elements are SndDhydroxld and Sn (II) oxalate.

To make the catalysts more effective, the Mo, X, and Y metal components should probably be something be reduced below their highest possible oxidation state. This can happen during heat treatment of the catalyst In the presence of reducing agents such as NHj or organic reducing agents, e.g. B. the organic complexing agents, which are introduced into the solution systems from which the catalysts are produced. The catalyst can also be used in the reactors to carry out the oxidation can be reduced by using hydrogen or hydrocarbon reducing agents such as ethane, ethylene or propylene, passes through the catalyst bed.

The deposited or non-deposited catalysts can be in a fixed or swirled Bed to be used.

The feedstock used as the source of ethane should be a gas stream that is at atmospheric pressure contains at least 3 vol .- 'A, ethane. Furthermore, he can use smaller amounts, i. H. <5% by volume, each of Hi, CO

and C 1-4 alkanes and alkenes. In addition, it can contain substantial amounts, ie> 5 vol. «, Of N ₂ , CH ₁ , CO ₂ and water as water vapor.

The catalysts used in the present invention appear to be of their ability to oxidize Ethane to be specific to ethylene as they do not oxydehydrogenate propane, η-butane and butene-1, but these Burn materials in carbon dioxide and other oxidized carbonaceous products.

The components of the gaseous used as the feed stream in the process of the invention Reaction mixture and the relative proportions of the components in the mixture are as follows:

1 mole of ethane,

ίο 0.01-0.5 moles of molecular oxygen (as pure oxygen or in the form of air) and

0-0.4 mol water (in the form of water vapor).

Water or steam is used as a reaction diluent and a heat moderator for the reaction. Other materials that can be used as reaction diluents or heat moderators are inert gases such as nitrogen, helium, CO ₂ and methane.

In the normal course of the reaction in the absence of added water, 1 mole of water is formed per mole of oxyrie-hydrogenated ethane. This water formed during the reaction in turn causes the formation of some acetic acid, ie about 0.05-0.25 mol per mol of ethylene formed. The water added to the feed stream causes additional amounts of acetic acid to be formed, a. H. up to about 0.25-0.95 moles of acetic acid per Μ mole of ethylene formed.

The components of the reaction mixture are uniformly grounded before they are introduced into the reaction zone mixed. The components are used individually or after mixing prior to their introduction into the reaction zone preheated to a temperature of 200-400 ° C.

The preheated reaction mixture is under the following conditions with the catalyst preparation in brought into contact with the reaction zone:

Pressure 1-30, preferably about 1-20 bar, temperature 200-400 ° C;

Contact time (reaction mixture on the catalyst) about 0.1-100, preferably 1-10, seconds, 3 »and

Space velocity 50-5000 hr ¹ , preferably 200-300 Ir ¹ .

The contact time can also be expressed as a ratio between the apparent volume of the catalyst bed and the volume of the gaseous reaction mixture can be defined under the given reaction conditions is fed to the catalyst bed in a unit of time.

The reaction pressure is initially created by the feed of the gaseous reactants and diluents. After commencement of the reaction, the pressure may preferably be maintained by ^w Before Using appropriate back pressure control devices which are situated on the side of the gaseous effluent of the catalyst bed.

The reaction temperature is preferably created by placing the catalyst bed in a tubular shape Converter there, the walls of which In a suitable heat transfer medium, such as tetralin, molten salt mixtures or other suitable heat transfer media, which are immersed at the desired reaction temperature be heated.

The process according to the invention can be used without added diluents, with the exception of water selective oxydehydrogenation before ethane to ethylene and acetic acid are applied to pertaining to this End products deliver the following results:

End product

5 (1

Ethylene (without added H ₂ O) *) Ethylene (with added H ₂ O) *) Acetic acid (without added H ₂ O) *) Acetic acid (with added water) *)

*) d. H. with or without water added to the ethane feed gas

The preferred catalysts for achieving the highest conversion and efficiencies on Ethy-.Ii Oil and acetic acid are calcined preparations which contain the elements Mo, V and Nb in the ratio Mo ,, V, Nb; is there

J = 16

c = 1 to 16, preferably i to 8

./ '= 0.2 to 10.

The following examples illustrate the present invention.

The following examples show the production of various catalyst preparations and their use

Ethane % Effectiveness productivity % Conversion 2-7 60-85 4 -7.5 2-8 50-80 2 -8.5 2-7 15-25 1.5-4 2-8 15-45 2.5-5

the oxydehydrogenation of ethane to ethylene.

The activity of each experimental catalyst was determined either in a kielnen U-shaped tubular reactor. Into which a pulsating stream of oxygen and ethane has been introduced (test method A): or in one straight pipe rcakior, into which ethane and oxygen were continuously introduced simultaneously (test method B); or in a backmix autoclave process (Test Method C). These test procedures were Im individual as follows:

Catalyst Test Procedure A

The catalysts were pulsing on their activity in relation to the oxydehydrogenation of ethane Microreactor system examined. The reaction section of 50 cm in length and containing the test catalyst 8 mm in diameter in the form of a silica U-tube was obtained by immersion in a swirling sand bath heated, the temperature of which was controlled by a heating element. The thermal elements for temperature control and measurements were immersed in the swirled sand, which extends at least 7.5 cm above the Catalyst level in the U-tube extended. A previous examination of the temperature profile in the sand bath showed less than 3 ° C change from head to floor from the fixed point given by the control device. The microreactor was connected to a gas chromatograph for analyzing the product streams. the

the helium supply line within the chromatograph at a point immediately after the flow control device interrupted, it was interrupted by a valve with 8 outlets and 2 positions (Union Carbide Corp., Special: n Instruments Division, Model C4-70) and from there through a manually operated sample injection valve with 6 outlets (Union Carbide Model 2112-50-2) led to the inlet arm of the U-tube reactor. The system was provided with an introduction opening which had a rubber septum at the reactor inlet. The product gas off the reactor was passed through a cold trap, back through the 8-outlet valve, containing the product stream to one of the two analysis systems of the chromatograph. Each valve had an adjustable Bypass valve fitted to compensate for the pressure drop in the chromatograph column in the analysis system.

The introduction of 2.0 ml swellings composed of 6.5% by volume oxygen, 8.0% by volume * ethane and the rest Nitrogen was applied through a gas-tight injection needle through the inlet immediately in front of the catalyst. The gas was diluted and passed over the catalyst (3.0 g) with the aid of the flelium carrier gas, the Carrier gas for analysis to each cell at 60 ml / ml by the reactor and the gas chromatograph streamed.

The product mixture was analyzed on a stainless steel column filled with Poropak R® with a diameter of 25 cm 3.2 mm. Starting from 30.degree. C., the column was heated at 10.degree. C./min. Under these conditions the residence times were as follows: air 2.0 min; Carbon dioxide 2.5 min; Ethylene M 3.4 min; Ethan 4.0 min The IdenUU! the products were confirmed by chromatography of known pure samples, and the severed tips were subjected to examination by mass spectrometry. "Poropak R" is a finely divided, spherical polystyrene resin crosslinked with divinylbenzene.

Catalyst test method B »

The catalysts were tested in a tubular reactor under the following conditions: Composition of the ethane feed: 9.0 vol .-% C ₂ H ₄ , 6.0 vol .-% O ₂ and 85 vol _{.-% 56 N 2} ; Space velocity 340 for ¹ ; 0.98 bar total reaction pressure. The catalyst efficiency was observed with increasing temperature. The reactor consisted of a 1.25 cm straight tube made of stainless steel, which was opened by means of a molten salt bath · »? des (using HITEC® heat transfer salt from DuPont) was heated from a depth of about 30 cm. A 3.2 mm thermal element arm extended the full length between the center of the reactor tube and the catalyst bed. The catalyst temperature profile was obtained by sliding the heating element through the arm. 26 ml of catalyst was introduced into the tube so that the top of the catalyst bed was 10 cm below the surface of the heat transfer salt. The catalytic converters ⁵ⁿ torbctt was 12.5 to 13.75 cm long, so that it had a ratio of depth to cross-section of> 10th The zone above the catalyst bed was filled with glass beads to serve as a preheater. The gaseous effluent from the reactor was passed through a condenser and a trap at 0 ° C. The gaseous and liquid products thus obtained were evaluated as described below.

Catalyst Test Procedure C

In this high-pressure study, a "Magnedrive" autoclave stirred at the bottom with a centrally mounted catalyst basket and a by-product outflow line was used as the reactor. A fan operated magnetically at different speeds circulated the reaction mixture continuously ^w over the catalyst bed. Such a reactor is shown in Fig. 1 of the study "Reactor for Vapor-Phase Catalytic Studies", published as reprint 42E at the Symposium on Advances in High-Pressure Technology - Part II, Sixty-fourth National Meeting of the American Institute of Chemical EngineciS ( AIChE), shown.

The backmix autoclave had a stainless steel catalyst container above the flights! of the fan; this thus blows the gas upwards and inwards in a convection fashion through the catalyst bed. Two heat elements measure the temperatures of the incoming and outgoing gas. The oxygen was through a rotameter Introduced into the reactor at about 11.2 bar through a 0.63 cm line. The gaseous ethane CC ^ Mixtures were introduced through a rotometer and then before introduction into the reactor with the acid

fabric covering united. The liquids were fed directly through the same feed line as the gases In The reactor was pumped, but the liquid flow occurred after the gases had been mixed. The outflow gas were removed through an exit on the reactor side. Condensable liquid products were produced by a Row Of Cold Traps Located In Two Baths. The first bath contained wet ice at 0 ° C and had two in it > submerged cold traps. The second bath of dry ice and acetone at -78 ° C contained two cold cases. the Non-condensable components of the exit stream were measured at atmospheric pressure by a dry gas test meter to determine your total volume. A valve with 8 outlets allowed that direct sampling of both product and feed gases through lines that connect directly to the Reactor feed and product streams were connected. There was no external regression

used in.

The missing volume of the weighed catalyst sample was determined (about 150 ml) and the sample became In given the catalyst basket. The amount of catalyst introduced in each case was about 131.1 g. Above and stainless steel screens were placed underneath the catalyst bed to facilitate fluidization and Keep circulation of the fine catalyst particles to a minimum. After the introduction of the catalyst basket in the reactor this was sealed and the process lines were at ambient temperatures tested to a pressure about 8-15 bar above the expected maximum working pressure. About this test nitrogen was used.

After the reactor was shown to be leak-free, pure Ni was leaked through the reactor and the temperature increased to 275-325 "C. The composition of the gas feed was in the following ranges

2i> varies: 76-97 % by volume of C ₂ H ₆ , 3-6% by volume, Oj, 0-10% by volume of HjO and 0-10% by volume of 96 CO ,. After the desired temperature had been reached, the oxygen and ethane-CO, mixtures were adjusted to give the desired equilibrium ratio at the desired total flow rate. The concentrations of the components in the effluent gas were determined by the gas chromatographic analyzes described below. The reactor was held for about 0.5-1 hour to reach equilibrium conditions

2 <desired temperature. The liquid product traps were then emptied, a dry gas test meter was read, and the beginning of the experiment was noted. In the course of the experiment, samples of the effluent gas were analyzed for C ₂ H ₄ , CjH ₄ , O ₂ CO, CO ₂ and other volatile hydrocarbons. At the end of the experiment, the nutty product was collected and the volume of the seed gas noted. The nut products were analyzed by mass spectroscopy.

. "ι The reactor and outlet gases from all tests carried out under test methods B and C were tested for O ₂ , N ₂ and CO on a 25 cm χ 3.2 mm column of 0.5 nm molecular sieves (1.17 / 0, 54 mm) at 95 ⁰ C and on (Oj, N ₂ , CO together) CO ₂ , ethylene, ethane and H ₂ O on a 35 cm χ 3.2 mm column made of »Poropak® Q« (0.175 / 0.147 mm) analyzed at 95 ° C. The liquid product (if obtained in sufficient quantity) was analyzed for H ₂ O, acetaldehyde, acetic acid and other components by mass spectroscopy.

^1S sated. »Pompak Q« ® is a finely divided, spherical polystyrene resin crosslinked with vinylbenzene.

In all cases the percent conversion and percent selectivity were based on the following Stoichiometry:

C ₂ H ₆ + Ά O ₂ > C ₂ H ₄ + H ₂ O

* · C ₂ H ₆ +% O ₂ >> 2CO ₂ + 3H ₂ O

without using individual response factors for the eluted peak values of the chromatogram.
The reaction conditions of the three test methods were as follows:

catalyst
test procedure Pressure;
bar Temperature;
⁰ C Contact time;
lake Space velocity .;
H-' A. 3.2 200-650 - B. 0.98 300-400 10.6 340 C. 5.9 -9.8 275-325 10.0 / 5.15 bar
15.6 / 8.6 bar 2200

Example 1 and 2

Catalyst 1 prepared below was evaluated in Catalyst Test Method A. The test result is found in Table 1. The catalyst of Example 2 was evaluated in Test Method B, its Results are also shown in Table 1.

The catalysts of Examples 1 and 2 were tested first to determine the lowest temperature at which caialytic activity was first demonstrated; this is referred to as the temperature of the initial activity (T ,,). The selectivity of the catalyst for the oxydehydrogenation of ethane to ethylene was then determined at this temperature. Both catalysts were then evaluated at higher temperatures in order _{to determine the lowest temperature above T a} at which a 10% conversion of ethane into ethylene could be achieved; this temperature is designated in Table 1 as T, _o . The selectivity of the catalyst with respect to the oxydehydrogenation of ethane to ethylene at T _{! 0} was also determined and is shown in Table I.

Example I.
MOi ₆ V ₄ Nb ₂ or Mo, V ₀₂₅ Nb ₀₁₃₅

82 g ammonium metavanadate (0.7 g atoms V) and 494 g ammonium paramolybdate (2.8 g atoms Mo) were dissolved in 2 l of water with stirring at 60-80 ° C. in a stainless steel evaporation vessel.

550 g of nloboxalate sol (0.35 g atoms of Nb) and 28 g of ammonium filtrate in 100% were added to the solution obtained ml of water ge'.ÖM added.

The resulting mixture was heated with stirring, then 1040 g (1000 ml) silica-alumina (Norton SA 5218) beads were added. Then, by evaporation under stirring on a \ u steam bath and further for 16 hours at 120 ° C.

The dried material was placed on a stainless steel wire tray with an open mesh width of 1.651 mm transferred and placed in a muffle furnace for 5 hours at 400 ° C in a surrounding air atmosphere calclnlert. The amount of catalyst deposited on the support, calculated from the increase in weight of the catalyst, was 27.7%. κ

The nloboxalate sol corresponded to an equivalent of 95.3 g / l Nb ₂ O ₅ .

Example 2
MonV ₄ NbjCui OdBrMo ₁ V ₀₂₅ Nb ₀ J ₂₅ Cu ₀₀₆₂₅

42 g ammonium metavanadate (0.36 g atoms V) and 254 g ammonium paramolybdate (, 144 g atoms Mo) were dissolved in 1.2 l of water with stirring at 60-80 ° C. in a stainless steel evaporation dish. To the received The solution was 158 g of nloboxalate (0.18 g atoms of Nb) and 22 g of Cu (II) nitrate (0.09 g atoms of Cu) in 60 ml Dissolved water, added.

The resulting mixture was heated with stirring, and there was 1040 g (1000 ml) of silica-alumina (Norton SA 5218) beads (6.3 mm) added. Then, by evaporation with stirring on a Steam bath and dried for a further 16 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and placed in a muffle furnace Calclnlert for 5 hours at 400 ° C in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 15.9%.

Table 1

Catalyst Test Results - Procedure A (or B *)

Example catalyst temperature of selectivity Temperature for! 0% selectivity

No. Composition Initial activity for C ₂ H ₄ Conversion of C ₂ H ₆ into C ₂ H ₄

° C (To)% at T ₀ ⁰ C (Ti ₀ )% at T, _o

1 Mo ₁₆ V ₄ Nb ₂ 215 Examples 100 286 2 * Mo ₁₆ V ₄ Nb ₂ Cu, 260 95 330 3 to 10

100
78

Catalysts 3 through 10 were made by the following procedures and the catalyst test procedure B evaluated. The composition of each catalyst is at the beginning of the corresponding example indicated, the test results can be found in Table 2.

Each catalyst 3 to 10 was hot-spot at one or two different "" -temperatures between 300 and 400 ° C to determine the percent conversion and efficacy with respect to the oxydehydrogenation of ethane to ethylene so evaluated.

Example 3
Mo ₁₆ V ₂ Nb ₂ or Mo ₁ V ₀ , 1 ₂₅ Nb ₀₁₂₅ 55

16 g ammonium metavanadate (0.136 g atoms V) and 192.4 g ammonium paramolybdate (1.09 g atoms Mo) were in 0.8 l of water with stirring at 85-95 ° C in an evaporation dish provided with a steam jacket solved from stainless steel.

124 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) in 100 ml of water (0.136 g atoms of Nb) were added to the solution obtained.

The obtained mixture was heated with stirring and dried by evaporation with stirring. the further drying took place at room temperature under total vacuum for 3 days.

The dried material was comminuted to a size of 2.36 × 4.7 mm and placed on a tray described in Example 1 transferred and calcined in a muffle furnace for 4 hours at 400 ° C in a surrounding air atmosphere. No support was added to the neat catalyst.

Example 4
Mo ₁₆ V ₄ Nb ₂ or Mo ₁ V ₀₂₅ Nb _0-125

<■ 40.9 g Ammonlummetavanadat (0.350 g-atoms V) Into 1.0 L of water with stirring at 85-95 ° C in a steam jacket provided with water Verdampfuntsschale released from stainless steel.

To the solution obtained, 159.2 g of nloboxalate solution (14.6% Nb ₂ O ₅ ), diluted with 100 ml of water (0.175 g atoms of Nb), and 247 g of ammonium paramolybdate (1.399 g atoms of Mo), dissolved in 800 ml of water , trains adds.

The resulting mixture was heated and dried by evaporation with stirring. Further drying was carried out for 16 hours at 12O ⁰ C.

The dried material was crushed to 2,36x4,7 mm and transferred to a tray and described In Example I calclnlert in a muffle furnace for 4 hours at 400 ⁰ C in an ambient air atmosphere. No support was added to the neat catalyst.

Example 5
Mo ₁₆ V ₄₆ Nb _n,; or MOiV ₀₃₈₈ Nb ₀₀₃₇₅

81.8 g ammonium metavanadate (0.7 g atoms V) and 494 g ammonium paramolybdate (2.8 g atoms Mo) were in 1.5 l of water with stirring at 85-95 ° C. In an evaporation dish provided with a steam jacket solved from stainless steel.

318.4 g of nloboxalate solution (14.6% Nb ₂ O ₅ ) in 200 ml of water (0.35 g atoms of Nb) were added to the solution obtained. The resulting slurry was filtered and the filtrate was left at room temperature for 3 days

- '> relaxed. More crystals formed and were filtered off. The final filtrate was added to In with stirring evaporated to dryness on a stainless steel evaporator. Further drying took place for 16 hours 120 ° C.

The dried material was comminuted to 2.36 × 4.7 mm and placed on a tray described in Example 1 transferred and calclnlert in a muffle furnace for 4 hours at 400 ° C in a surrounding air atmosphere.

No support was added to the neat catalyst. The analysis showed the above composition.

Example 6
Mo ₁₆ V ₈ Nb ₂ or Mo ₁ V ₀ J ₇₅ Nb _0-125

61.4 g of ammonium metavanadate (0.525 g atoms V) were In 1.0 l of water with stirring at 85-95 ° C In a stainless steel evaporation dish provided with Wasscrdampfrnantci.

275 g of nloboxalate solution (8.45% Nb ₂ O ₅ ) (0.175 g atoms of Nb) and 2 × 7 g of ammonium paramolybdate (1.399 g atoms of Mo), dissolved in 800 ml of water, were added to the solution obtained.

The mixture obtained was heated <dried by evaporation with stirring. The further drying took place for 16 hours at 120 ° C.

The dried material was comminuted to 2.36 × 4.7 mm and placed on a tray described in Example 1 transferred and caidnlert in a muffle furnace for 4 hours at 400 ° C in a surrounding air atmosphere. No support was added to the neat catalyst.

Example 7
MOi ₆ V ₈ Nb ₀₅ or MOiV ₀₅ Nb ₀₀₃ I.

5n 16 g ammonium metavanadate (0.136 g-atoms V) and 48.1 g ammonium paramolybdate (0.272 g-atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C. in an evaporation dish provided with a steam jacket solved from stainless steel.

7.75 g of nloboxalate solution (14.6% Nb ₂ O ₅ ) (0.0085 g atoms of Nb) were added to the solution obtained. The resulting mixture was heated with stirring, and 140 g of silica-alumina (Norton No. 5218 of 2.36 × 4.7 mm, irregular shape) were added. Then it was dried by evaporation with stirring and further 16 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and placed in a muffle furnace Calcined for 4 hours at 400 ° C in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 23.2%.

Example 8
MOi ₆ V ₈ Nb ₂ or Mo ₁ V ₀₅ Nb _{0 i2S}

15. ¹ J ρ Amnuiniunimetavanadat iü, i36 g-atoms V) and 48.1 g ammonium paramolybdate (0.272 g-atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C in a steam-jacketed evaporation according to stainless Steel loosened.

31.0 g of nloboxalate solution (14.6% Nb ₂ O ₅ ) (0.034 g atoms of Nb) were added to the solution obtained.

The resulting mixture was heated with stirring, and 145 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and dried for a further 16 hours at 120.degree.

The dried material was transferred to a method described in Example 1 tray and calcined in a muffle furnace for 4 hours at 400 ° C in a surrounding LuftatmosphSre was deposited on the support The amount of catalyst, calculated from the weight increase of the catalyst, 19.7 ¹ V

Example 9 Mo ₁₆ V ₁₂ ^ Nb _10. , Or Mo ₁ V ₀ J ₀₆ Nb ₀₆₃

22.5 g ammonium metavanadate (0.192 g atoms V) and 42.1 g ammonium paramolybdate (0.238 g atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C. in an evaporation dish provided with a steam jacket solved from stainless steel.

137.7 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) (0.151 g atoms of Nb) and 12.6 g of ammonium nitrate (NH ₁ NOj) (0.157 Mo!) Were added to the solution obtained.

The resulting mixture was heated with stirring, and 160 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and further dried for 16 hours at 120.degree.

The finished material was transferred to a tray described in Example 1 and placed in a muffle furnace Calcined for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 20.3%.

Example 10 Mo ₁₆ V _21-3 Nb _3-7 or

42.4 g ammonium metavanadate (0.362 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C. in an evaporation dish provided with a steam jacket solved from stainless steel.

57.4 g of niobium oxalate solution (14.6% NbjO ₅ ) (0.063 g atoms of Nb) and 5.0 g of ammonium nitrate (NH ₄ NO ₃ ) (0.062 mol), dissolved in 30 ml of water, were added to the solution obtained.

The resulting mixture was heated with stirring, and 160 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and further! dried for 6 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and placed in a muffle furnace Calcined for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 24.2%.

Table 2

Test results of catalysts 3 to 10 according to method B

example
No. catalyst
composition Metal oxides
in the catalytic converter catalyst
»Hot spot«
⁰ C Ethane
conversion effectiveness
in ethylene 3 Mo ₁₆ V ₂ Nb ₂ 100 300 12th 86 4th Mo ₁₆ V ₄ Nb ₂ 100 300 29 83 5 Mo ₁₆ V ₄ , ₆ Nb ₀ . _6th 100 300
378 29
65 81
51 6th Mo ₁₆ V ₆ Nb ₂ 100 300 28 83 7th Mo, ₆ V ₈ Nb ₀ .5 23.2 322
400 1.4
12th 100
76 8th Mo ₁₆ V ₈ Nb ₂ 19.7 300
400 12th
50 91
68 9 Mo ₁₆ V ₁ ^ Nb ₁₀ ,, 20.3 300
400 track
8th 85 10 Mon ₁₆ V _{2,. 3} Nb ₃ .7 24.2 315
400 2
20th 83
46 Examples Il to 17

Catalysts 11-17 were prepared and evaluated in Test Procedure B by the following procedure; the test results are shown in Table 3.

The catalysts of Example II to 17 were at two "hot-spot" temperatures between 300-400 ° C for

20th 25th 30th 35 40

60

Determine the percent conversion and potency at each of these temperatures with respect to the Evaluated oxydehydrogenation of ethane to ethylene.

Example 11

Mo ₁₆ V ₄ Nb ₂ K ₀₄ or Mo ₁ V ₀ J ₅ Nb _0-125 K _0-031

8.0 g ammonium metavanadate (0.068 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C in a steam-jacketed evaporation "» stainless steel bowl detached.

0.85 g of potassium nitrate (KNO ₃ ) (0.0084 g atoms of K) and 31 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) (0.034 g atoms of Nb) and 2.8 g of ammonium nitrate ( NH ₄ NO ₃ ) (0.035 mol) was added.

The resulting mixture was heated with stirring, and 150 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and is dried for a further 16 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and placed in a muffle furnace Calcined for 4 hours at 400 "C. in a surrounding air atmosphere. The deposited on the support The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 17.9%.

Example 12

Mo ₁₆ V ₈ Nb ₂ Ce ₂ or Mo, V ₀₄ Nb ₀ , 1 ₂₅ Ce _0-125

15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C in an evaporation vessel provided with a steam jacket solved from stainless steel.

31 g of niobium oxalate solution (14.6% Nb ₃ O ₅ ) in 100 ml of water (0.034 g atoms of Nb) and 14 g of cerium nitrate (41.8 «CeO ₂ ) (0.034 g atoms of Ce) in 150 ml of water dissolved, added.

The resulting mixture was heated with stirring, and 150 g of silica-alumina (Norton No. 3 "5218 of 2.36 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and further dried for 16 hours at 120.degree.

The dried material was transferred to a tray described in Example 1 and placed in a muffle oven Calcined for 4 hours at 400 "C. in a surrounding air atmosphere. The deposited on the support The amount of the catalyst, calculated from the increase in the weight of the catalyst, was 28%.

Example 13
Mo ₁₆ VgNb ₂ Co ₂ or Mo ₁ V ₀₄ Nb _0- I ₂₅ Co _0-125

*> 15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were in 0.5 l of water with stirring at 85-95 ° C. in an evaporation dish provided with a steam jacket solved from stainless steel.

31 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) in 100 ml of water (0.034 g atoms of Nb) and 8.5 g of cobalt acetate [Co (CHjCOO) ₂ · 4H ₂ O] (0.034 g atoms Co), dissolved in 150 ml of water, added.

The mixture obtained was heated with stirring, and 150 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and further dried for 16 hours at 120.degree.

The dried material was transferred to a tray described in Example 1 and placed in a muffle furnace Calcined for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier

5 ^f i amount of catalyst, calculated from the increase in weight of 1st catalyst, was 26.3%.

Example 14
Mo ₁₆ V ₈ Nb ₂ Cu ₂ or M

15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were In 0.5 l of water with stirring at 85-95 ° C. In an evaporation vessel provided with a steam jacket solved from stainless steel.

31 g of niobium oxalate solution (14.6% Nb ₂ Os) in 10Q ml of water (0.034 g> atoms of Nb) w * and 6.8 g of Cu (! I) acetate [(CHjCOO) jCu · H ₂ O] were added to the solution obtained. (0.034 g-atoms Cu), dissolved in 150 ml of water, added.

The mixture was heated with stirring and 150 g of silica-alumina (Norton No. 5218 from 2.36 4.7 mm. irregular shape) added. Then by evaporation with stirring and further Dried 16 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and placed in a muffle oven calcined for 4 hours at 400 ° C in a surrounding air atmosphere. The deposited on the carrier The amount of catalyst, calculated from the increase in the weight of the catalyst, was 25.1 '. »..

IO

Example 15 Mo ₁₆ V ₈ Nb ₂ Fe ₂ or MO | V ₀ ^ Nbo., 25 ^Fe o.! 25

15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were dissolved in 0.5 l of water with stirring at 85-95 ° C. in a stainless steel evaporation vessel provided with a steam jacket.

31 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) in 100 ml of water (0.034 g atoms of Kb) and 6.4 g of FedIDoxalate [Fe ₂ (C ₂ O _{4 I 3} ] (0.034 g atoms Fe), dissolved in 150 ml of water plus 4.4 g of oxalic acid, was added.

The resulting mixture was heated with stirring, and 150 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.17 mm, irregular shape). Then, by evaporation with stirring and further dried for 16 hours at 120.degree.

The dried material was transferred to a tray described in Example 1 and calcined in a muffle furnace for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier The amount of catalyst, calculated from the increase in weight of the catalyst, was 23%.

Example 16 Mo ₁₆ V ₈ Nb ₂ Ni ₂ or Mo ₁ V ₀ JNb _0-125 Ni _0-125

15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were dissolved in 0.5 l of water with stirring at 85-95 ° C. in a stainless steel evaporation vessel provided with a steam jacket.

To the resulting solution were added 31 g Nioboxalatlösung (14.6% Nb ₂ O ₅₎ 100 ml in water (0.034 g-atom of Nb) and 8.5 g of nickel acetate [Ni (C ₂ H ₃ O j) ₂ - 4H ₂ O] ( 0.034 g atoms Ni), dissolved in 150 ml of water, added.

The resulting mixture was heated with stirring, and 150 g of silica-alumina (Norton No. 5218 of 2.36 × 4.7 mm, irregular shape) were added. It was then dried by evaporation with stirring and a further 16 hours at 120 ^{° C.}

The dried material was transferred to a tray described in Example 1 and calcined in a muffle furnace for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst calculated from the increase in the weight of the catalyst was 26.456.

Example 17 Mo ₁₆ V ₈ Nb ₂ U ₁ or Mo, V ₀₁₅ Nb ₀₁₁₃₅ Uo ₁ OiJ ₅

15.9 g ammonium metavanadate (0.136 g atoms V) and 48.1 g ammonium paramolybdate (0.272 g atoms Mo) were dissolved in 0.35 l of water with stirring at 85-95 ° C. in a stainless steel evaporation dish provided with a steam jacket.

31 g of niobium oxalate solution (14.6% Nb ₂ O ₅ ) (0.034 g atoms of Nb) and 7.2 g of uranyl acetate [(CH ₃ COO) ₂ UO ₂ · 2H ₂ O] (0.017 g atoms of U ) added.

The resulting mixture was heated with stirring, and 140 g of silica-alumina (Norton No. 5218 of 2.36 χ 4.7 mm, irregular shape) was added. Then, by evaporation with stirring and welter dried for 16 hours at 120 ° C.

The dried material was transferred to a tray described in Example 1 and calcined in a muffle furnace for 4 hours at 400 ° C. in a surrounding air atmosphere. The deposited on the carrier The amount of the catalyst calculated from the increase in the weight of the catalyst was 27%.

Table 3

Catalyst test results for Catalyst 11-17 in Procedure B

35 40 45 50

example
No. catalyst
composition Metal oxides
in the catalytic converter
% catalyst
»Hot-spot«
⁰ C Ethane
conversion
% effectiveness
in ethylene
% 55 11th Mo ₁₆ V ₄ Nb ₂ K _0-5 17.9 338
400 6th
24 89
73 12th Mo ₁₆ V ₈ Nb ₂ Ce ₂ 28 300
400 8.6
39.4 84 «ι
56 13th MOi ₆ V ₈ Nb ₂ Co ₂ 26.3 300
400 6th
29 94
59 14th MOi ₆ V ₈ Nb ₂ Cu ₂ 25.1 300
400 6th
42 79 ₆₅
52 15th Mc ₆ V ₈ Nb ₂ Fe ₂ 23
1 1 300
400 8th
42 82
57 ^:

continuation catalyst
composition 26 44 107 Ethane
conversion
% effectiveness
in ethylene
% example
No. MOi ₆ V ₈ Nb ₂ Ni ₂
Mo ₁₆ V ₈ Nb ₂ U, Metal oxides
in the catalytic converter
% catalyst
»Hot spot«
"C 5
33
12th
53 93
59
91
64 16
17th 26.4
27 300
400
300
4CO

Examples 18-20

The catalyst of Example 5 (Mo ₁₆ V ₄₆ Nb _0-6 ) was used in three experiments (Examples 18-20) in the oxydehydrogenation of ethane to ethylene in the absence or presence of added water to demonstrate its ability under these circumstances To produce acetic acid. In Examples 18 and 19 no water was added; in Example 20 this was the case. The reaction conditions present (pressure, temperature, inlet composition of the gas, inlet speed of the water and its outlet speed) and the test results (% selectivity, productivity and conversion) are shown in Table 4. The catalyst was evaluated by Test Procedure C in Examples 18-20.

Table 4
Oxydehydrogenation of ethane with catalyst Moi ₆ V _4-6 Nb ₀ , ₆ be: the production of acetic acid

example
No. Total pressure
bar Reaction
temperature Gas inlet
composition; % Water inlet
speed Water outlet
speed ⁰ C O ₂ C ₂ H ₄ Moi / std-> 18th 6.1 275 3.2 89.1 0.0 0.37 19th 6.1 322 6.0 90.0 0.0 0.83 20th 9.6 323 6.5 85.8 0.98 1.5 continuation example
No. Ethane
conversion
% effectiveness
InC ₂ H ₄
% C ₂ H.
productivity
kg / m ³ KatVstd. effectiveness
in CH ₃ COOH
% CHjCOOH
productivity
kg / m 'cat./hour 18th 3.1 85.0 60.8 13.2 20.8 19th 6.9 73.1 119.2 18.8 64 20th 7.5 67.6 131.2 18.4 76.8

Claims (1)

Patent claims: 1. Process for the oxydehydration of ethane for the production of ethylene and acetic acid, thereby characterized in that one ethane catalytically at a temperature of 200 to 400 ° C and a pressure Oxydehydrogenated from 1 to 30 bar in the gas phase, the catalyst, which is optionally on a Carrier is a calcined preparation containing the elements Mo, X and Y in the following ratio is: