CN101121131B - Ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst - Google Patents

Abstract

The present invention relates to a fluidized bed catalyst of unsaturated nitrile which is produced by an ammoxidation. The present invention mainly solves the problems in the prior art that a yield of an acrylonitrile catalyst in the reaction of the industrial device is not high, and the yield is gradually reduced with the prolonged time; the by-product s of CO2, CO and HCN are increased; the stability of the catalyst is not good enough. The present invention solves the problems well by a technical proposal that a catalyst carrier is selected from SiO2 or Al2O3a or a mixture of SiO2 and Al2O3, and the catalyst contains active components, the general formula of which is as follows: in the formula of Mo12BiaFebNicXdYeZfQgOx, the X is selected from at least one of Mg, Co, Ca, Be, Cu, Zn, Pb,Mn or Te; the Y is selected from at least one of La, Ce or Sm; the Z is selected from at least one of K, Rb, Na, Li or Cs; the Q is selected from at least one of Ga, Ge or Pr. The present invention can be used for the industrial production of acrylonitrile which is produced by a propylene ammoxidation.

Description

Ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst

Technical field

The present invention relates to a kind of ammonia oxidation and produce the fluid catalyst of unsaturated nitrile, produce about propylene, butylene ammoxidation particularly that propylene is fine, the fluid catalyst of butene nitrile.

Background technology

The ammoxidation of alkene prepares α, in exploitation sixties last century in last century, the core technology of this technology is to use a kind of active component to contain the catalyst of Mo, Bi to beta unsaturated nitrile technology by BP company.Through constantly improving, the Mo-Bi series catalysts is very ripe at present, is widely used by preparing acrylonitrile by allylamine oxidation technology industrial.The improvement of catalyst is in the past mainly carried out from activity of such catalysts and stable aspect, as adding transition metal to improve activity in active constituent, increases the single of product and receives; Add rare earth element and improve redox ability; Add elements such as Na, P to improve the wearability of catalyst; Add elements such as Fe, Co, Ni to suppress the distillation of Mo, improve stability of catalyst or the like.

Patent CN 99119905.7, CN 99119906.5, CN 97106771.6 and CN 96101529.2 have all introduced the improved Mo-Bi catalyst that is used for propylene, isobutene ammonia oxidizing system unsaturated nitrile catalyst, the advantage of these catalyst has oxidation-reduction stability and reaction yield preferably preferably, and reacting ammonia is lower than empty ratio and reaction temperature.

Patent CN 01113194.2, CN 01113193.4 and CN 01113192.6 introduced in catalyst preparation process, get part metals and organic ligand, chelating agent or surfactant separately the method for preparation improve catalyst at low ammonia than the performance under the reaction condition.

Patent CN 03151170.8 and CN 03151169.4 have introduced in the catalyst preparation process, and the solid silica that adds 2～25% grain diameter and be 5～100 nanometers in carrier starting material Ludox improves catalyst performance.

Summary of the invention

Technical problem to be solved by this invention is that the prior art acrylonitrile catalyst is not high at the commercial plant reaction yield, and reduces accessory substance CO gradually along with time lengthening ₂, CO, HCN rise, catalyst stability becomes the problem of one of industry focus, and a kind of fluid catalyst that is used for new propylene, isobutene ammonia oxidizing system unsaturated nitrile is provided.This catalyst is suitable for moving under the when lower reaction temperature condition of lower sky ratio, ammonia, has good catalyst reaction activity and stable.

For solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst, and to be selected from SiO ₂, Al ₂O ₃Or its mixture be carrier, the active constituent that contains is by following general formula:

Mo ₁₂Bi _aFe _bNi _cX _dY _eZ _fQ _gO _x

Wherein: X is selected from least a among Mg, Co, Ca, Be, Cu, Zn, Pb, Mn or the Te;

Y is selected from least a among La, Ce or the Sm;

Z is selected from least a among K, Rb, Na, Li or the Cs;

Q is selected from least a among Ga or the Pr;

The span of a is 0.1～6.0;

The span of b is 0.1～10.0;

The span of c is 0.1～10.0;

The span of d is 0.1～10.0;

The span of e is 0.1～9.5;

The span of f is＞0～0.5;

The span of e+f sum is 0.15～10.0;

The span of g is＞0～5.0;

X satisfies the required oxygen atom sum of other element valence, and the consumption of carrier is 30～70% of a catalyst weight.

The value preferable range of a is 0.2～4.0 in the technique scheme; The value preferable range of b is 0.5～5.0; The value preferable range of c is 1.0～8.0; The value preferable range of d is 0.5～5.0; The value preferable range of e is 0.2～2.0; The value preferable range of f is 0.01～0.5; The value preferable range of e+f sum is 0.2～2.0; The value preferable range of g is 0.1～4.0, and more preferably scope is 0.2～1.0; Carrier consumption preferable range is 40～60% of a catalyst weight.

Catalyst can prepare with the coprecipitation that those skilled in the art are familiar with.The starting material of required metallic element is corresponding water soluble salt, the dissolving of metallic element starting material is made mixed salt solution later, and make slurry with coprecipitation with the carrier starting material, the aging back of slurry spray drying granulation, high-temperature roasting obtains the catalyst finished product then, and sintering temperature is 500 ℃～610 ℃.

In the following embodiment that provides, be to the investigation appreciation condition of catalyst:

Reactor: fluidized-bed reactor, 38 millimeters of internal diameters

Catalyst filling amount: 550 grams

Reactor top pressure: 0.084MPa (gauge pressure)

Reaction temperature: 430 ℃

Reaction time: 4 hours

Raw material ratio: interior alkene/ammonia/air=1/1.1/9.5

WWH:0.06 hour ^-1

Product absorbs with 0 ℃ of diluted acid, with gas-chromatography and chemical analysis binding analysis product.And the calculating Carbon balance, when Carbon balance is valid data during at (95～105) %.

Propylene conversion, acrylonitrile yield and optionally be defined as:

The present invention is by the synergy of alkaline earth element, alkali metal and characteristic element Ga, Ge and the Pr of introducing, suppressed preferably that the generation of accessory substance keeps higher catalyst activity simultaneously in the ammoxidation reaction, improve catalyst target product yield and stability significantly, obtained better technical effect.

The present invention is further elaborated below by embodiment.

The specific embodiment

[comparative example 1]

With 441.4 gram (NH ₄) ₆Mo ₇O ₂₄4H ₂O joins in the warm water of 70 ℃ of 330 grams, stirs and makes its whole dissolvings, and the Ludox that adds 1400 grams 40% (wt.) is made material A.

With 213.1 gram Fe (NO ₃) ₃9H ₂O adds in 70 ℃ of hot water of 150 grams, adds 201.8 gram Bi (NO after the stirring and dissolving again ₃) ₃5H ₂O, 274.8 gram Ni (NO ₃) ₃6H ₂O, 96.3 gram Mg (NO ₃) ₃6H ₂O, 72.5 gram La (NO ₃) ₃3H ₂O, 18.6 gram Sm (NO ₃) ₃3H ₂Make material B after the O stirring and dissolving.

In 20 gram water, add 1.1 gram KNO ₃, 0.9 the gram NaNO ₃With 2.0 gram CsNO ₃To form material C among its adding material B after the dissolving.

Material C is dripped in material A under stirring fast, form catalyst pulp.In 70 ℃ of spray-dryings after aging 3 hours, with the particle of gained in rotary calciner in 580 ℃ of following roastings 3 hours, finished catalyst.

[embodiment 1～11]

According to the identical preparation process of comparative example, form preparation according to table 1 catalyst.Finished catalyst is investigated by above-mentioned investigation appreciation condition, and initial activity the results are shown in Table 2.The stability tests in 250 hours of comparative example 1 and embodiment 5 the results are shown in Table 3.

Table 1 catalyst

Table 2 embodiment investigates the result

Table 3 catalyst stability result of the test

Claims (4)

1. ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst is to be selected from SiO ₂, Al ₂O ₃Or its mixture be carrier, the active constituent that contains is by following general formula:

Mo ₁₂Bi _aFe _bNi _cX _dY _eZ _fQ _gO _x

Wherein: X is selected from least a among Mg, Co, Ca, Be, Cu, Zn, Pb, Mn or the Te;

Y is selected from least a among La, Ce or the Sm;

Z is selected from least a among K, Rb, Na, Li or the Cs;

Q is selected from least a among Ga or the Pr;

The span of a is 0.1～6.0;

The span of b is 0.1～10.0;

The span of c is 0.1～10.0;

The span of d is 0.1～10.0;

The span of e is 0.1～9.5;

The span of f is 0.01～0.5;

The span of e+f sum is 0.15～10.0;

The span of g is 0.1～4.0;

X satisfies the required oxygen atom sum of other element valence, and the consumption of carrier is 30～70% of a catalyst weight.

2. ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst according to claim 1, the span that it is characterized in that a is 0.2～4.0; The span of b is 0.5～5.0; The span of c is 1.0～8.0; The span of d is 0.5～5.0; The span of e is 0.2～2.0; The span of e+f sum is 0.2～2.0.

3. ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst according to claim 1, the span that it is characterized in that g is 0.2～1.0.

4. ammoxidation method to manufacturing unsaturated nitrile fluid-bed catalyst according to claim 1, the consumption that it is characterized in that carrier is 40～60% of a catalyst weight.