CN1199729C - Prepn and application of novel catalyst for oxidizing isobutene or tert-butyl alcohol to prepare methy acraldehyde - Google Patents

Abstract

The invention relates to a novel catalyst for producing methacrolein and its application. The catalyst composition involved is (Mo _a Bi _b Fe _c B _d X _e ¹ Y _f ¹ O _g ) _I + (Mo _h Co _i B _j X _k ² Y _l ² O _m ) _II , where X ¹ , X ² is at least one kind of alkali metal, Y ¹ and Y ² are at least one kind of lanthanide elements, a, b, c, d, e, f, g, h, i, j, k, l, m represent each The atomic ratio of an element. The composite catalyst can be obtained by crystal form optimization and step-by-step preparation. The catalyst obtained by the invention has high activity, good selectivity and excellent strength and stability. The catalyst is used to catalyze the oxidation of isobutene, tert-butanol or a mixture thereof to produce methacrolein with molecular oxygen, and a high yield can be obtained.

Description

The preparation and the application thereof of iso-butylene or Oxidation of t-Butanol system Methylacrylaldehyde new catalyst

Technical field the present invention relates to a kind of composition, preparation and application of using the new catalyst of molecular oxygen selective oxidation iso-butylene or trimethyl carbinol system Methylacrylaldehyde.

(Methyl methacrylate is important organic chemical industry's product MMA) to the background technology methyl methacrylate, is the topmost polymerization single polymerization monomer of acrylic resin plastics.At present domesticly all produce with traditional acetone cyanohydrin method (ACH method).Because the raw materials used severe toxicity of ACH law technology route and corrodibility height, by product is many and Atom economy poor (only being 26.99%), now developed new alternative techniques route abroad, wherein with C ₄It is main that derivative is produced MMA technology.

C ₄The operational path that derivative is produced MMA is: iso-butylene (trimethyl carbinol) → Methylacrylaldehyde → methacrylic acid → methyl methacrylate or iso-butylene (trimethyl carbinol) → Methylacrylaldehyde → methyl methacrylate.The present invention relates generally to the catalyzer of first section oxidation, i.e. the catalyzer of iso-butylene or the trimethyl carbinol → Methylacrylaldehyde.This section catalyzer as the catalyzer of hydrocarbon selective oxidation have all the time that intensity is little, selectivity is low, poor stability, the shortcoming that auxiliary agent is more and some auxiliary agent toxicity are big that relates to.

Up to now, the catalyzer of existing multiple composition and various proportionings relates to and is used for iso-butylene or Oxidation of t-Butanol prepares Methylacrylaldehyde.At present basicly stable is being the skeleton of catalyzer with molybdenum bismuth system, adds various auxiliary agents or adds second kind of composition and improve activity of such catalysts and selectivity.With Japanese catalyst company is the molybdenum bismuth series catalysts that tungstenic has then mainly been developed in representative, as disclosed US 4537874, US4873217, CN1029228C, US5276178, CN1060154C, CN1280036A, etc.Tungsten be considered to can with the bismuth stable bond, thereby can partly replace the effect of molybdenum within the specific limits.But the solubleness of tungstate in water is little, easily causes environmental pollution.

In catalyst composition, except molybdenum and bismuth, the main component of forming catalyzer also has iron and cobalt.Experimental results show that iron and cobalt can be in bigger atom ratio range remarkably influenced activity of such catalysts and selectivity.It is generally acknowledged that iron can regulate the oxidation-reduction quality of molybdenum bismuth system, suppress deep oxidation; Cobalt then is that to guarantee that catalyzer has high active requisite.

The catalyzer for preparing propenal with propylene oxidation is compared, it is more outstanding and be absolutely necessary basically that basic metal prepares effect in the catalyzer of Methylacrylaldehyde in iso-butylene or Oxidation of t-Butanol, in recent years disclosed patent, the CN1143946A of the US5892108 of MIT, company of Japanese Asahi Chemical Industry for example, CN1280036A of the US5583086 of German BASF AG, Japanese catalyst company etc. has used basic metal with higher ratio in catalyzer.Have some patents to mention and replace alkali-metal effect, but the toxicity of thallium is very high with thallium.

Rare earth has excellent catalysis characteristics because of its special 4f electron structure.The effect of rare earth in the catalyzer for preparing Methylacrylaldehyde with iso-butylene or Oxidation of t-Butanol in recent years more and more receives publicity.Generally believe rare earth in catalyst for oxidation reaction, can strengthen stocking and flowability of lattice oxygen, therefore can improve activity of such catalysts and selectivity and resistance to reduction.Rare earth has outstanding effect aspect the thermostability that improves catalyzer in addition.Disclosed patent such as US5138100, US5728894, CN1280036A etc. have used rare earth element clearly.

Summary of the invention catalyzer of the present invention has added boron as auxiliary agent on molybdenum bismuth iron cobalt system, improved catalyzer the selectivity of Methylacrylaldehyde has also been improved activity of such catalysts, intensity and stability to a certain extent.Simultaneously, the component of this catalyzer is fairly simple, and raw material solubleness in water is bigger, is easy to preparation.In addition, catalyzer component toxicity is little, is easy to reclaim, and has environment friendly.

Its composition is:

${\left({\mathrm{Mo}}_a{\mathrm{Bi}}_b{\mathrm{Fe}}_c{B}_d{X}_e^1{Y}_f^1{O}_g\right)}_I+{\left({\mathrm{Mo}}_h{\mathrm{Co}}_i{B}_j{X}_k^2{Y}_l^2{O}_m\right)}_{\mathrm{II}}---\left(1\right)$

Wherein Mo is that molybdenum, Bi are that bismuth, Fe are that iron, B are that boron, Co are cobalt, X ¹, X ²For alkali-metal at least a, Y ¹, Y ²At least a for lanthanon, a, b, c, d, e, f, g, h, i, j, k, l, m represent every kind of atoms of elements ratio respectively.

Wherein, 0＜a≤7,0＜b≤5,0＜c≤4,0＜d≤3,0＜e≤2,0≤f≤3,3≤h≤9,3≤i≤9,0＜j≤6,0＜k≤3,0≤l≤4, g, m are respectively and form the needed oxygen atomicity of certain crystal formation.And during a+h=12,1≤d+j≤5,0＜e+k≤3,0≤f+l≤5.

Add the important component of boron in the present invention as catalyzer.In disclosed patent such as US5583086, US5892108, US5532199, US5856259, CN1032462C, CN1099024A etc., all mention boron, but do not occurred its concrete service condition in an embodiment.It is approaching with the character of silicon that the character of boron is considered in the periodic table of elements.Silicon generally adds with the form of carrier in catalyzer, does not participate in solid state reaction basically, and also can reduce selectivity of catalyst to a certain extent.And among the present invention, boron joins in the ammonium molybdate solution with the form of boric acid, and then with the aqueous nitric acid mixed precipitation of other component, in the drying and roasting process just certain solid state reaction may take place, uniform distribution forms certain crystal formation and structure.Experimental result shows that the adding of boron has significantly improved selectivity of catalyst, and especially effect is obvious under high conversion, has improved the intensity and the stability of catalyzer simultaneously.Catalyzer of the present invention has reached high usefulness with better simply composition, thereby has simplified preparation, has reduced cost.

Preparation of Catalyst of the present invention can adopt the method for the whole components of catalyzer being carried out certain distribution combination back substep preparation.Be specially: certain component that will contain molybdenum, cobalt, boron etc. is earlier carried out co-precipitation, prepares composition I the I ((Mo with certain crystal formation _hCo _iB _jX _k ²Y _l ²O _m) _II); After this composition I I ground, join the containing in molybdenum, the B solution of another part; Mix certain hour then, carry out the co-precipitation of all the other components (bismuth, iron, boron etc.); Obtain final catalyzer through shaping and roasting at last $({\left({\mathrm{Mo}}_a{\mathrm{Bi}}_b{\mathrm{Fe}}_c{B}_d{X}_e^1{Y}_f^1{O}_g\right)}_I+{\left({\mathrm{Mo}}_h{\mathrm{Co}}_i{B}_j{X}_k^2{Y}_i^2{O}_m\right)}_{\mathrm{II}}).$

At disclosed patent US 5583086A, the catalyzer that iso-butylene or Oxidation of t-Butanol prepare Methylacrylaldehyde has also adopted the method for separated into two parts, substep preparation, owing to the specific crystal formation that obtains in the preparation process makes selectivity of catalyst better.This patent catalyzer does not use the tungsten salt of indissoluble in the preparation, and adopts the mode of optimizing crystal formation, two portions all appropriateness contain Mo, B and basic metal, significantly different on component with two portions of patent US 5583086A, the catalyst selectivity that obtains also obviously is better than patent US 5583086A.

This patent is in catalyst preparation process, after the component that some solubleness are bigger is prepared into composite oxides in advance, be mixed into the co-precipitation of the surplus component in Xingqi again with ammonium molybdate solution, can prevent effectively that bigger, the water-soluble cobalt ion preferably of add-on from the ion segregation taking place after drying and roasting, cause solid state reaction inhomogeneous, not exclusively or form inhomogeneous and make the integer catalyzer degradation.And very favorable crystal conversion has taken place in catalyzer after a period of stabilisation, thereby the performance of catalyzer is significantly improved.

The forming method of catalyzer is not particularly limited, can extrusion molding or pelletizing forming, also can load on the conventional carriers such as carrier such as Alpha-alumina, silicon carbide, silicon-dioxide, titanium oxide.

Transformation efficiency among the present invention and selectivity definition are as follows:

The present invention is described as follows with embodiment:

Embodiment 1:

Preparation of catalysts:

794 gram ammonium molybdates and 31 gram boric acid are dissolved in the about 50 ℃ water of 1854 gram temperature, make solution A; 15 gram saltpetre and 1091 gram Xiao Suangus are dissolved in the 600g water, make solution B; At 40-80 ℃, solution A and solution B are mixed, stir about is 2 hours simultaneously, makes slurry.With this slurry 110 ℃ of dryings 12 hours, 200 ℃ of calcinings 3 hours, 460 ℃ of roastings 3 hours, grind composition I I.

265 gram ammonium molybdates and 15 gram boric acid are dissolved in the about 50 ℃ water of 2100 gram temperature, add composition I I then, mix 1h, get suspension liquid C; With 364 gram Bismuth trinitrates, 242 gram iron nitrates, 10 gram saltpetre are dissolved in 15% aqueous nitric acid of 900g, get solution D; At 40-80 ℃, suspension liquid C and solution D are mixed, stir about is 2 hours simultaneously, makes slurry.With this slurry 110 ℃ of dryings 12 hours, 200 ℃ of calcinings 3 hours, the solid compressing tablet that obtains is the 4.5mm cylinder.Then with the catalyst composition after the moulding 500 ℃ of roastings 3 hours, final catalyzer.With atomic ratio (eliminating oxygen) expression, it consists of (Mo3Bi1.5B0.5Fe1.2K0.2) _I(Mo9Co7.5K0.3B1.0) _II

Catalyzed reaction:

With the 100ml catalyzer that the obtains single tube fixed-bed reactor of packing into, make and contain volume ratio: iso-butylene: oxygen: nitrogen: water vapour=1: 2.2: 7.8: 1.5 mixed gas is by this reactor, and air speed is 1800h ^-1, temperature of reaction is 360 ℃ and reacts.With gas-chromatography reaction is monitored, its result is as shown in table 1.

Comparative Examples 1 (1):

Preparation of catalysts:

1059 gram ammonium molybdates and 46g boric acid are dissolved in the about 50 ℃ water of 5000 gram temperature, make solution A; With 364 gram Bismuth trinitrates, 242 gram iron nitrates, 25 gram saltpetre and 1091 gram Xiao Suangus are dissolved in 15% aqueous nitric acid of 900g, make solution B; At 40-80 ℃, solution A and solution B are mixed, stir about is 2 hours simultaneously, makes slurry.With this slurry 110 ℃ of dryings 12 hours, 200 ℃ of calcinings 3 hours, the solid compressing tablet that obtains is the 4.5mm cylinder.Then with the catalyst composition after the moulding 500 ℃ of roastings 3 hours, final catalyzer.With atomic ratio (eliminating oxygen) expression, it consists of Mo12B2.0Bi1.5Fe1.2Co7.5K0.5.

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses Comparative Examples 1 (1) to obtain carries out catalyzed reaction, and temperature of reaction is 380 ℃.The result is as shown in table 1 for its reaction monitoring.

When catalyzed reaction, temperature of reaction reduces, and has better activity and selectivity than the catalyzer that uses general co-precipitation preparation method to obtain for the comparative descriptions of embodiment 1 and Comparative Examples 1 (1), the preparation method that catalyzer of the present invention uses.

Comparative Examples 1 (2):

Preparation of catalysts:

1059 gram ammonium molybdates are dissolved in the about 50 ℃ water of 5000 gram temperature, make solution A; With 364 gram Bismuth trinitrates, 242 gram iron nitrates, 25 gram saltpetre and 1091 gram Xiao Suangus are dissolved in 15% aqueous nitric acid of 900g, make solution B; At 40-80 ℃, solution A and solution B are mixed, stir about is 2 hours simultaneously, makes slurry.With this slurry 110 ℃ of dryings 12 hours, 200 ℃ of calcinings 3 hours, the solid compressing tablet that obtains is the 4.5mm cylinder.Then with the catalyst composition after the moulding 500 ℃ of roastings 3 hours, final catalyzer.With atomic ratio (eliminating oxygen) expression, it consists of Mo12Bi1.5Fe1.2Co7.5K0.5.

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses Comparative Examples 1 (2) to obtain carries out catalyzed reaction, and temperature of reaction is 380 ℃.The result is as shown in table 1 for its reaction monitoring.

The comparative descriptions of Comparative Examples 1 (1) and Comparative Examples 1 (2), added boron in the catalyzer after, selectivity of catalyst is significantly increased.

Embodiment 2:

Preparation of catalysts:

The preparation method of preparation composition I I replaces the 10 gram saltpetre except that restraining cesium nitrates with 19 when second step prepared with embodiment 1, and other is with embodiment 1.

The final catalyzer that obtains is with atomic ratio (eliminating oxygen) expression, and it consists of (Mo3Bi1.5B0.5Fe1.2Cs0.2) _I(Mo9Co7.5K0.3B1.0) _II

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses embodiment 2 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Comparative Examples 2:

Preparation of catalysts:

Except that not adding in the preparation process of composition I I the saltpetre, all the other are with embodiment 2.Catalyzed reaction: (Mo3Bi1.5B0.5Fe1.2Cs0.2) _I(Mo9Co7.5B1.0) _II

With the method identical with embodiment 1, the catalyzer that uses Comparative Examples 2 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Embodiment 2 comparison shows that with Comparative Examples 2, does not add basic metal in composition I I, and active and selectivity all has bigger decline.

Embodiment 3:

Preparation of catalysts:

The preparation method of preparation composition I I is with embodiment 1, and except that add 109 gram cerous nitrates in solution D, other is with embodiment 1 when second step prepared.

The final catalyzer that obtains is with atomic ratio (eliminating oxygen) expression, and it consists of (Mo3Bi1.5B0.5Fe1.2Ce0.5K0.2) _I(Mo9Co7.5K0.3B1.0) _II

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses embodiment 3 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Embodiment 4:

Preparation of catalysts:

The added 31g boric acid, all the other are with embodiment 1 when replacing with 15g boric acid that composition I I prepares among the embodiment 1.With atomic ratio (eliminating oxygen) expression, final catalyzer consists of (Mo3Bi1.5B0.5Fe1.2K0.2) _I(Mo9Co7.5K0.3B0.5) _II

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses embodiment 4 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Embodiment 5:

Preparation of catalysts:

The added 31g boric acid, other is with embodiment 1 when replacing with 46g boric acid that composition I I prepares among the embodiment 1.With atomic ratio (eliminating oxygen) expression, final catalyzer consists of (Mo3Bi1.5B0.5Fe1.2K0.2) _I(Mo9Co7.5K0.3B1.5) _II

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses embodiment 5 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Embodiment 6:

Preparation of catalysts:

Remove when second step prepared, add in solution D outside the 109 gram cerous nitrates, other is with embodiment 2.

With atomic ratio (eliminating oxygen) expression, final catalyzer consists of (Mo3Bi1.5B0.5Fe1.2Ce0.5Cs0.2) _I(Mo9Co7.5K0.3B1.0) _II

Catalyzed reaction:

With the method identical with embodiment 1, the catalyzer that uses embodiment 6 to obtain carries out catalyzed reaction, and temperature of reaction is 360 ℃.The result is as shown in table 1 for its reaction monitoring.

Embodiment 7:

Catalyzed reaction:

With the method identical with embodiment 1, use the catalyzer of embodiment 1 preparation, carry out catalyzed reaction with the iso-butylene among the trimethyl carbinol steam replacement embodiment 1, temperature of reaction is 360 ℃.The result is as shown in table 2 for its reaction monitoring.

Table 1

Embodiment	Catalyzer is formed (eliminating oxygen)	Temperature of reaction (℃)	Isobutene conversion (mol%)	Overall selectivity (mol%)	Total once through yield (mol%)
						1	(Mo3Bi1.5B0.5Fe1.2K0.2) I (Mo9Co7.5K0.3B1.0) II	360	98.6	85.7	84.5
Comparative Examples 1 (1)	Mo12B2.0Bi1.5Fe1.2Co7.5K0.5	380	92.0	79.1	72.8
						Comparative Examples 1 (2)	Mo12Bi1.5Fe1.2Co7.5K0.5	380	90.2	72.2	65.1
2	(Mo3Bi1.5B0.5Fe1.2Cs0.2) I (Mo9Co7.5K0.3B1.0) II	360	98.8	87.5	86.5
						Comparative Examples 2	(Mo3Bi1.5B0.5Fe1.2Cs0.2) I (Mo9Co7.5B 1.0) II	360	96.9	83.3	80.7
3	(Mo3Bi1.5B0.5Fe1.2Ce0.5K0.2) I (Mo9Co7.5K0.3B1.0) II	360	97.3	86.6	84.3
						4	(Mo3Bi1.5B0.5Fe1.2K0.2) I (Mo9Co7.5K0.3B0.5) II	360	97.8	84.0	82.2
5	(Mo3Bi1.5B0.5Fe1.2K0.2) I (Mo9Co7.5K0.3B1.5) II	360	99.4	80.9	80.4
						6	(Mo3Bi1.5B0.5Fe1.2Ce0.5Cs0.2) I (Mo9Co7.5K0.3B1.0) II	360	98.5	89.1	87.8

Annotate: overall selectivity and total once through yield comprise Methylacrylaldehyde and methacrylic acid.

Table 2

Embodiment	Catalyzer is formed (eliminating oxygen)	Temperature of reaction (℃)	Trimethyl carbinol transformation efficiency (mol%)	Overall selectivity (mol%)	Total once through yield (mol%)
						7	(Mo3Bi1.5B0.5Fe1.2K0.2) I(Mo9Co7.5K0.3B1.0) II	360	100	87.0	87.0

Annotate: overall selectivity and total once through yield comprise Methylacrylaldehyde and methacrylic acid.

Claims (3)

1, the iso-butylene and the trimethyl carbinol is at least a, carry out a kind of catalyzer that gaseous oxidation prepares Methylacrylaldehyde with the gas of molecule-containing keto, it consists of:

Wherein Mo is that molybdenum, Bi are that bismuth, Fe are that iron, B are that boron, Co are cobalt, X ¹, X ²For alkali-metal at least a, Y ¹, Y ²At least a for lanthanon, a, b, c, d, e, f, g, h, i, j, k, l, m represent every kind of atoms of elements ratio respectively, wherein, 0＜a≤7,0＜b≤5,0＜c≤4,0＜d≤3,0＜e≤2,0≤f≤3,3≤h≤9,3≤i≤9,0＜j≤6,0＜k≤3,0≤1≤4, g, m is respectively and forms the needed oxygen atomicity of certain crystal formation, and during a+h=12,1≤d+j≤5,0＜e+k≤3,0≤f+1≤5, (MohCo _iB _jX _k ²Y _l ²O _m) _IIWith (Mo _aBi _bFe _cB _dX _e ¹Y _f ¹O _g) _IHas independently crystalline phase respectively;

Method for preparing catalyst is: certain component that will contain molybdenum, cobalt, boron is carried out co-precipitation, prepares the composition I I (Mo with certain crystal formation _hCo _iB _jX _k ²Y _l ²O _m) _II, after then this composition I I being ground, join another part and contain in the solution of molybdenum, boron, mix certain hour, carry out the co-precipitation of all the other components, last shaping and roasting gets final catalyzer

2, catalyzer according to claim 1, one or more the combination of using Alpha-alumina, silicon carbide, silicon-dioxide, titanium oxide is as carrier.

3, catalyzer according to claim 1, the forming method of employing spraying drying, extrusion, compressing tablet.