CN103418400A

CN103418400A - Fluidized-bed catalyst for preparing unsaturated nitrile by ammoxidation

Info

Publication number: CN103418400A
Application number: CN2012101504942A
Authority: CN
Inventors: 姜家乐; 吴粮华; 张顺海
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2012-05-16
Filing date: 2012-05-16
Publication date: 2013-12-04

Abstract

The invention relates to a fluidized-bed catalyst for preparing unsaturated nitrile by ammoxidation, and mainly solves the problems that in the prior art the lattice oxygen content of a catalyst for acrylonitrile is low, deep oxidation of propylene is easy to occur, the acrylonitrile selectivity is low to cause the low yield of the acrylonitrile. According to the fluidized-bed catalyst for preparing the unsaturated nitrile by ammoxidation, through use of a technical scheme, the problems are well solved. The technical scheme is shown as follows: the fluidized-bed catalyst uses silica sol as a carrier, and contains an active component represented by the following general formula: Mo[12]Bi[a]Fe[b]Ni[c]X[d]Y[e]Z[f]K[g]O[x], wherein b/(a+e)=1.0-3.5. The fluidized-bed catalyst can be used in industrial production of preparation of the acrylonitrile by ammoxidation of the propylene.

Description

Unsaturated nitrile fluid catalyst prepared by ammoxidation

Technical field

The present invention relates to a kind of fluid catalyst of prepared by ammoxidation unsaturated nitrile, particularly about the fluid catalyst of propylene, butylene preparing acrylonitrile by ammoxidation, butene nitrile.

Background technology

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

Patent CN 99119905.7, CN 99119906.5, CN 97106771.6 and CN 96101529.2 have all introduced the improved Mo-Bi catalyst for propylene, isobutene ammonia oxidizing unsaturated nitrile catalyst processed, 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 reaction condition.

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

The conversion ratio of above patented technology to the raising catalyst, the discharge of ammonia ratio and then minimizing amine wastewater of sulphuric acid in the reduction course of reaction, there has been certain effect the aspects such as the life-span of extending catalyst; Yet the report of patent up to now, all exist acrylonitrile catalyst Lattice Oxygen content low, and deep oxidation easily occurs propylene, and acrylonitrile is selectively low, causes the problem that acrylonitrile yield is low.

Summary of the invention

One of technical problem to be solved by this invention is in prior art, to exist acrylonitrile catalyst Lattice Oxygen content low, deep oxidation easily occurs in propylene, acrylonitrile is selectively low, causes the problem that acrylonitrile yield is low, and a kind of new unsaturated nitrile fluid catalyst prepared by ammoxidation is provided.It is high that this catalyst has Lattice Oxygen content, selective high oxidation reaction occurs in the Lattice Oxygen in propylene and catalyst, and suppress it, with gas phase oxygen generation deep oxidation, reacts, and acrylonitrile is selectively high, for the reaction of prepared by ammoxidation unsaturated nitrile, the advantage that acrylonitrile yield is high.

For solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of unsaturated nitrile fluid catalyst prepared by ammoxidation, take Ludox as carrier, and contain the active component that following general formula means:

Mo ₁₂Bi _aFe _bNi _cX _dY _eZ _fK _gOx

Wherein:

X is at least one being selected from Mg, Co, Ca, Be, Cu, Zn, Pb, Mn or Te;

Y is at least one being selected from La, Ce or Sm;

Z is at least one being selected from Rb, Li or Cs;

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 b/ (a+e) is 1.0～3.5;

The span of f is > 0～0.5;

The span of g is > 0～0.2;

X meets the required oxygen atom sum of other element valence, and the consumption of carrier is catalyst weight 30～70%; Wherein the span of b/ (a+e) is 1.0～3.5.

The preferred span of b/ in technique scheme (a+e) is 1.5～2.5; The value preferable range of g is 0.01～0.1; The consumption preferable range of carrier is catalyst weight 40～60%; The calcination activation temperature preferable range of catalyst is 550～640 ℃; Calcination activation time preferable range is 0.5～2 hour.

Catalyst can be familiar with those skilled in the art coprecipitation preparation.The starting material of required metallic element is corresponding water soluble salt, make slurry with the Ludox carrier by coprecipitation, the aging rear spray drying granulation of slurry, then high-temperature roasting obtains the catalyst finished product, calcination activation temperature preferable range is 550～640 ℃, and calcination activation time preferable range is 0.5～2 hour.

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

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

Catalyst filling amount: 550 grams

Reactor top pressure: 0.084 MPa (gauge pressure)

Reaction temperature: 430 ℃

Reaction time: 4 hours

Raw material ratio: propylene/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, be valid data during at (95～105) %.

Propylene conversion, acrylonitrile yield and optionally be defined as:

Unreacting propylene C molal quantity

Propylene conversion (%)=1-

* 100 %

All product C molal quantitys (comprising unreacting propylene)

Generate acrylonitrile C molal quantity

Single-pass yield of acrylonitrile (%)=

* 100 %

All product C molal quantitys (comprising unreacting propylene)

Single-pass yield of acrylonitrile

Acrylonitrile selective (%)=

* 100 %

Propylene conversion

The present invention is by optimizing the ratio of b/ (a+e) in the acrylonitrile catalyst formula, effectively improved Lattice Oxygen content in catalyst, thereby the non-selective oxidation reaction that has suppressed gas phase oxygen in propylene and unstripped gas, it is the deep oxidation reaction, and effectively increase the selective oxidation reaction of propylene and Lattice Oxygen, and then it is selective to have significantly improved acrylonitrile, acrylonitrile yield obviously improves.As shown in table 2 result: the Lattice Oxygen of catalyst is increased to the approximately 200 μ mol/g of embodiment by 65 μ mol/g of comparative example 1,1～3 times of rising ratio, and effect is remarkable; Acrylonitrile selectively is increased to 86% left and right of embodiment by 80.3% of comparative example 1, single-pass yield of acrylonitrile is increased to approximately 84% by 78.5%, has obtained technique effect preferably.

Below by embodiment, the present invention is further elaborated.

The specific embodiment

[comparative example 1]

By the Ludox of 1400 grams 40% (weight), stir 0.5 hour, obtain material A.

By 441.4 gram (NH ₄) ₆Mo ₇O ₂₄4H ₂O joins in the warm water of 70 ℃ of 330 grams, stirs and makes it all dissolve and obtain material B, A is added fast in the B of strong stirring, obtains material C.

By 213.1 gram Fe (NO ₃) ₃9H ₂O adds in 70 ℃ of hot water of 150 grams, adds 201.8 gram Bi (NO after 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 D after the O stirring and dissolving.

Add 1.1 gram KNO in 20 gram water ₃, 0.9 gram NaNO ₃With 2.0 gram CsNO ₃After dissolving, it is added in material D and form material E.

Material E is dripped under rapid stirring in material C, form catalyst pulp.In 70 ℃ of spray-dryings after aging 3 hours, by the particle of gained in rotary calciner in 580 ℃ of lower roastings 3 hours, obtain finished catalyst.

[embodiment 1～15]

The identical preparation process according to comparative example 1, form Kaolinite Preparation of Catalyst according to table 1 catalyst, by above-mentioned investigation appreciation condition, investigated, and activity rating result and Lattice Oxygen content analysis the results are shown in Table 2.

Table 1 catalyst

?	Catalyst forms
		Comparative example 1	Mo ₁₂Bi _2.0Fe _2.5Ni _4.5Mg _1.8La _0.8Sm _0.2K _0.05Cs _0.05Na _0.05+50%SiO ₂
Embodiment 1	Mo ₁₂Bi _1.2Fe _2.5Ni _4.6Co _2.0Ce _0.7K _0.07+46%SiO ₂
		Embodiment 2	Mo ₁₂Bi _0.5Fe _1.9Ni _5.8Mg _2.3La _0.8K _0.1Rb _0.08+46%SiO ₂
Embodiment 3	Mo ₁₂Bi _0.2Fe _2.0Ni _6.8Mg _0.9 Sm _0.6K _0.1Cs _0.05+50%SiO ₂
		Embodiment 4	Mo ₁₂Bi _0.4Fe _1.5Ni _4.5Co _4.0La _0.5K _0.02 Cs _0.09+52%SiO ₂
Embodiment 5	Mo ₁₂Bi _0.5Fe _3.2Ni _3.0Mg _1.8La _0.8Sm _0.2K _0.05Cs _0.05+50%SiO ₂
		Embodiment 6	Mo ₁₂Bi _0.2Fe _2.8Ni _5.3Mn _0.7Ce _0.8Ca _0.2K _0.11Cs _0.05+50%SiO ₂
Embodiment 7	Mo ₁₂Bi _0.9Fe _4.9Ni _3.5Mg _1.8Pb _0.2Ce _1.3 K _0.12Cs _0.13+52% SiO ₂
		Embodiment 8	Mo ₁₂Bi _0.7Fe _2.5Ni _5.5Ce _0.3 K _0.15Cs _0.1Li _0.05 +47%SiO ₂
Embodiment 9	Mo ₁₂Bi _2.0Fe _3.0Ni _4.5Mg _2.3La _0.2K _0.05Cs _0.1Zr _0.03+48%SiO ₂
		Embodiment 10	Mo ₁₂Bi _1.0Fe _2.5Ni _6.5Mg _1.8Ce _0.2K _0.08Rb _0.05Cs _0.05 +50%SiO ₂
Embodiment 11	Mo ₁₂Bi _0.3Fe _2.1Ni _4.3Mg _2.2Ce _0.4K _0.12Cs _0.07Li _0.03 +51%SiO ₂
		Embodiment 12	Mo ₁₂Bi _0.4Fe _1.6Ni _4.8Mg _1.8La _0.2Sm _0.4K _0.15Cs _0.05+50%SiO ₂
Embodiment 13	Mo ₁₂Bi _1.1Fe _3.8Ni _3.3Mn _0.5Ce _0.3Ca _0.2K _0.11Cs _0.09 +50%SiO ₂
		Embodiment 14	Mo ₁₂Bi _0.4Fe _2.0Ni _3.8Mg _1.8Ce _0.2K _0.06Rb _0.07Cs _0.08 +50%SiO ₂
Embodiment 15	Mo ₁₂Bi _0.7Fe _2..7Ni _2.0Mg _2.4Ce _0.3K _0.14Cs _0.12+51%SiO ₂

Table 2 catalyst is investigated result

?	Single-pass yield of acrylonitrile (%)	Acrylonitrile selective (%)	Propylene conversion (%)	Lattice Oxygen content μ mol/g
					Comparative example 1	78.5	80.3	97.8	65
Embodiment 1	81.6	85.2	95.8	108
					Embodiment 2	82.7	86.1	96.1	121
Embodiment 3	85.1	86.4	98.5	258
					Embodiment 4	83.5	86.8	96.2	176
Embodiment 5	84.3	85.5	98.6	231
					Embodiment 6	84.3	86.1	97.9	265
Embodiment 7	85.6	86.3	99.2	241
					Embodiment 8	84.7	87.2	97.1	256
Embodiment 9	81.8	83.5	98.0	157
					Embodiment 10	83.3	84.1	99.0	211
Embodiment 11	85.1	86.6	98.3	242
					Embodiment 12	83.5	85.7	97.4	172
Embodiment 13	85.1	86.9	97.9	216
					Embodiment 14	84.0	85.4	98.4	233
Embodiment 15	84.8	85.2	99.5	218

Claims

1. a unsaturated nitrile fluid catalyst prepared by ammoxidation, take Ludox as carrier, contains the active component that following general formula means:

Mo ₁₂Bi _aFe _bNi _cX _dY _eZ _fK _gO _x

Wherein:

X is at least one being selected from Mg, Co, Ca, Be, Cu, Zn, Pb, Mn or Te;

Y is at least one being selected from La, Ce or Sm;

Z is at least one being selected from Rb, Li or Cs;

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 b/ (a+e) is 1.0～3.5;

The span of f is > 0～0.5;

The span of g is > 0～0.2;

2. unsaturated nitrile fluid catalyst prepared by ammoxidation according to claim 1, the span that it is characterized in that b/ (a+e) is 1.5～2.5.

3. unsaturated nitrile fluid catalyst prepared by ammoxidation according to claim 1, the consumption that it is characterized in that carrier is catalyst weight 40～60%.