CN102249835A - Selective hydrogenation method of alkyne and alkadiene in C4 hydrocarbon material flow - Google Patents

Abstract

The invention provides a selective hydrogenation method of alkyne and alkadiene in a C4 hydrocarbon material flow. The method provided by the invention comprises the following steps of: adding the C4 hydrocarbon material flow containing alkyne and/or alkadiene and hydrogen gas into a hydrogenation reactor which is filled with a load type palladium catalyst; carrying out the selective hydrogenation on the alkyne and/or alkadiene in the C4 hydrocarbon material flow to form olefin when an inlet temperature is in a range of 10-80 DEG C, a mol ratio of the hydrogen gas to the sum of the alkyne and the alkadiene is 1-10 and a reaction pressure is in a range of 0.1-4 Mpa, and removing the olefin, wherein the load type palladium catalyst comprises a carrier, palladium and selective modified components; testing the load type palladium catalyst by utilizing a carbon monoxide adsorption in-situ infrared spectroscopy at the temperature of 40 DEG C to obtain an area ratio of a bridge type absorption peak at the 1930-1990cm<-1> to a bridge type absorption peak at the 1870-1930cm<-1> in an obtained infrared spectrogram is less than 0.2, more preferably less than 0.15. The method provided by the invention has a high selectivity to the selective hydrogenation of the alkyne and the alkadiene in the C4 hydrocarbon material flow and can be operated for a long period.

Description

The selection method of hydrotreating of alkynes and diolefine in carbon four hydrocarbon streams

Technical field

The present invention relates to a kind of selection method of hydrotreating, more particularly, the present invention relates to a kind of process for selective hydrogenation that is used for carbon four hydrocarbon stream alkynes and diolefine.

Background technology

The mixed c 4 fraction is the mixture of the multiple alkane that contains 4 carbon atoms, alkene, diolefine, alkynes, be mainly derived from the refinery gas of petroleum refining process generation and the by-product of petroleum hydrocarbon cracking process of producing ethylene, contain normal butane, Trimethylmethane, 1-butylene, anti--2-butylene, suitable-2-butylene, iso-butylene, 1 in the cracking c_4,2-divinyl, 1, stable hydrocarbon and unsaturated hydrocarbons such as 3-divinyl, methylacetylene, ethylacetylene, vinylacetylene, industrial production is mainly used to produce 1,3-butadiene, iso-butylene and butylene.Producing with cracking c_4 in the method for butylene, a kind of is that cracking c_4 is directly carried out selective hydrogenation, with wherein 1,2-divinyl, 1,3-divinyl, ethylacetylene, vinylacetylene hydrogenation generate 1-butylene, anti--2-butylene, suitable-monoolefines such as 2-butylene, will avoid the further hydrogenation of monoolefine to generate alkane simultaneously; Another kind method is earlier with 1, the 3-divinyl is from separating the cracking c_4, the residue by product that mainly contains butane and carbon four monoolefines that obtains is become carbon four raffinates, often contain 1 about 1.0wt% in carbon four raffinates, the 3-divinyl needs with the method for selective hydrogenation this part butadiene hydrogenation to be removed.

The loading type Pd catalyzer is selected hydrogenation catalyst for carbon commonly used four.In actual applications, require catalyzer to have high selectivity for the reaction that MAPD selects to be hydrogenated to butylene.The selectivity of Pd is directly related with the kind of the exposed sites of Pd, adopts specific preparation method to control the crystal face form in Pd site, can improve the performance of catalyzer.As in Japanese Patent JP 2000202287, be the Pd precursor with the salpeter solution of dinitrobenzene two ammino palladiums, make it with after carrier combines, by direct reduction or regulate and control the physical property of palladium metal by reductive method after the thermal treatment.For Pd/Al ₂O ₃Catalyzer, when the specific surface area of Pd at 1～150m ²In the time of in/g the scope, the crystal face of palladium is (100) and (110); When the specific surface area of Pd at 150～350m ²In the time of in/g the scope, the crystal face of palladium is (111).U.S. Pat 20060243641 provides a kind of reforming catalyst, and the atom on its surface at least 50% is (110) crystalline structure, and specific metallic crystalline structure obtains by add control agents such as polyacrylic acid in preparation process.U.S. Pat 6746597 provides a kind of loaded noble metal catalyst, and its polycarboxylic acid who comprises waits the metal organic sequestering agent that metallics is mainly existed with (111) crystalline phase.

Above document is the wide in range crystal face feature that has provided catalyzer, and the crystalline form ratio to precious metal does not limit.Owing to need comprise specific Pd precursor or crystal control agent in the preparation process, it is complicated that the composition of catalyzer becomes, and preparation process is also more loaded down with trivial details.In addition, the catalyzer precious metal surface is to influence its active and important factor optionally to the adsorptive power of reactant, embodies in existing document.Therefore be necessary on the basis that the catalyst analysis feature is clearly limited, the process for selective hydrogenation of alkynes and diolefine in a kind of carbon four hydrocarbon streams is provided.

Summary of the invention

The object of the present invention is to provide the selection method of hydrotreating of alkynes and diolefine in a kind of carbon four hydrocarbon streams.

Concrete technical scheme is as follows:

The selection method of hydrotreating of alkynes and diolefine in a kind of carbon four hydrocarbon streams, carbon four hydrocarbon streams that will comprise alkynes and/or diolefine enter the hydrogenator that load type palladium catalyst is housed with hydrogen, 10～80 ℃ of temperature ins, making alkynes and/or diolefin hydrogenate in the olefin stream under the mol ratio 1～10 of hydrogen and alkynes and diolefine sum and the reaction pressure 0.1～4Mpa is that alkene is removed;

Described load type palladium catalyst comprises carrier, palladium and optional modified component, it is characterized in that described catalyzer in 40 ℃ of carbon monoxide absorption in-situ ft-ir figure that test down, 1930～1990cm ^-1Place's bridge-type absorption peak and 1870～1930cm ^-1The ratio of the area of place's bridge-type absorption peak is less than 0.2.

Preferably, described catalyzer adsorbs among the in-situ ft-ir figure at 40 ℃ of carbon monoxide of testing down, 1930～1990cm ^-1Place's bridge-type absorption peak and 1870～1930cm ^-1The ratio of the area of place's bridge-type absorption peak is less than 0.15.

More preferably described catalyzer is at 40 ℃ down behind the absorption carbon monoxide, uses 1870～1930cm among the in-situ ft-ir figure that nitrogen purging records in the time of 0 minute instead ^-1The peak height of place's absorption peak with use 1800～1900cm among the in-situ ft-ir figure that nitrogen purging records in the time of 15 minutes instead ^-1The ratio of the peak height of place's absorption peak is less than 5, preferably less than 2.

The carbon monoxide absorption infrared spectrogram of catalyzer adopts following method to record:

A) catalyst sample with powdered form places hydrogen gas stream to be warming up to 300 ℃; Temperature rise rate is 20 ℃/min, and hydrogen flowing quantity is 10ml/min;

B) in hydrogen gas stream, be incubated 2 hours down, be cooled to 40 ℃ then in 300 ℃; Rate of temperature fall is 20 ℃/min, and hydrogen flowing quantity is 10ml/min;

C) keeping temperature is 40 ℃, feeds stream of nitrogen gas and purges 30 minutes, and nitrogen flow is 5ml/min;

D) keeping temperature is 40 ℃, feeds carbon monoxide-argon gas gas mixture (molar content of carbon monoxide is 1%), adsorbs 30 minutes, and mixed gas flow is 5ml/min;

E) keeping temperature is 40 ℃, uses nitrogen purging instead, simultaneously the in-situ ft-ir of the carbon monoxide of working sample absorption at once figure;

F) keeping nitrogen flow is 5ml/min, writes down the in-situ ft-ir figure of sample when nitrogen purging 9min, 15min, 24min respectively.

Before testing, should be earlier granular catalyst sample be ground to Powdered, fill in the original position sample pool and keep surfacing.The purpose of step a～c is that the Pd in the catalyzer is reduced to the simple substance attitude, and removes the absorption impurity of catalyst surface.For going back the catalyzer of ortho states, palpus is through the treatment step of a～c, to guarantee test result accurately and reliably equally for Pd.

Finish at the carbon monoxide adsorption step (step d) and use nitrogen purging instead in, write down the infrared spectrogram (promptly purging 0 minute spectrogram) of sample at once, the carbon monoxide absorption in-situ ft-ir figure as this sample is used for 1870～1930cm ^-1Place's bridge-type absorption peak and 1930～1990cm ^-1The calculating of place's bridge-type absorption peak area.Using nitrogen purging to write down the infrared spectrum of sample after 15 minutes once more,, calculate 1800～1900cm with the spectrogram contrast that purges 0 minute ^-1Place's absorption peak (purging 15 minutes spectrograms) and 1870～1930cm ^-1The ratio of the peak height of place's absorption peak (purging 0 minute spectrogram).

In the CO of Pd absorption in-situ ft-ir, 1880～1990cm ^-1The place has two tangible infrared absorption peaks usually, corresponding to the bridge-type absorption of CO on the different loci of Pd surface.For different Pd catalyzer, the relative intensity of two absorption peaks has bigger difference, and common two summits overlap, and one of them summit becomes the acromion at another peak in some cases.In order to calculate the area ratio of two absorption peaks, can use data processing software commonly used to 1750～2000cm ^-1Interval absorption curve carries out the swarming match.For some sample, if specify two known peak positions can't obtain the matched curve that is consistent with absorption curve, then should be at 1880cm ^-1Near match peak of increase, this match peak are not counted in and participate in correlated peak area corresponding to triple ADSORPTION STATE of CO.Those skilled in the art can judge the quantity and the position at match peak easily, and calculate the area at each match peak.

Among the CO absorption in-situ ft-ir figure of described catalyzer, 1870～1930cm ^-1Place's bridge-type absorption peak and 1930～1990cm ^-1The ratio of place's bridge-type absorption peak area limits, thereby the assurance catalyst surface has a particular types Pd site, and then has guaranteed that catalyzer has specific reaction preference.

After using nitrogen to purge, the intensity of CO infrared absorption peak weakens gradually.1870～1930cm ^-1The CO bridge-type absorption absorption peak at place is with red shift to 1800 gradually～1870cm ^-1Triple absorption absorption peaks and final the disappearance are changed in the place.Purge 15 minutes spectrogram 1800～1900cm ^-10 minute spectrogram 1870～1930cm of place's absorption peak and purging ^-1The ratio of the peak height of place's absorption peak can be used for showing the adsorption strength of CO on the Pd surface, limits this ratio and can guarantee that catalyzer has suitable adsorptive power for specific reactants, and then guarantee that catalyzer has specific reaction preference and activity.

Described catalyzer is catalytic active component with Pd, and its content is 0.01～50wt% of carrier gross weight, is preferably 0.01～10wt%, more preferably 0.03～5wt%.Pd is a kind of in simple substance attitude, oxide compound and other Pd compounds or two or more mixed state in them in the form that exists of catalyst surface.

The carrier of described catalyzer can be selected from a kind of in gac, carbon black, carbon nanotube, aluminum oxide, wilkinite, clay, diatomite, zeolite, molecular sieve, titanium oxide, magnesium oxide, silicon oxide and the polymer materials or two or more mixture in them.Special-shaped strips such as that the shape of carrier includes but not limited to is Powdered, granular, spherical, sheet, tooth are spherical, strip or trifolium.Optional 1～the 500m of the specific surface area of carrier ²/ g is preferably 1～200m ²/ g, more preferably 1～80m ²/ g.

Described catalyzer can be loading type list Pd catalyzer, also can comprise loading type Pd catalyzer modified component commonly used.Modified component is selected from Bi, Sb, Pb, In, be different from least a in group VIII element, IB group element, rare earth element, alkali metal, alkali earth metal and the haloid element of palladium, and its content is 0～20wt% of carrier gross weight.Modified component can be used as and helps active ingredient to be distributed in the specific position of carrier, and the properties-correcting agent that also can be used as carrier is uniformly distributed among the carrier.

Another object of the present invention is to provide a kind of method for preparing above-mentioned loading type Pd catalyzer.This method is characterised in that and comprises following steps: the solution that (1) uses spraying method will comprise the palladium precursor is carried on the carrier; (2) use the load of ionizing rays irradiation that the system of carrier, water and the free-radical scavengers of palladium precursor is arranged.

In preparation method of the present invention, preferably before the palladium precursor solution is loaded to carrier, use basic solution to regulate pH to 2～13 of palladium solution; Perhaps use basic solution to handle carrier before or after the supported palladium precursor, described treatment process is spraying.Wherein said basic solution includes but not limited to the aqueous solution and ammoniacal liquor such as sodium hydroxide, potassium hydroxide, sodium bicarbonate, yellow soda ash for the basic cpd aqueous solution commonly used.

In preparation method of the present invention, described ionizing rays can be selected from gamma-rays, X ray or electron beam; Gamma ray source is optional ⁶⁰Co (γ source), ¹³⁷Cs (γ source), x-ray source or rumbatron (electron beam), preferred ⁶⁰Co, x-ray source or rumbatron, more preferably ⁶⁰Co.The absorbed dose rate of the ionizing rays that described ionizing rays irradiation is used is 1～1 * 10 ⁷Gy/min, preferred 10～10000Gy/min, more preferably 20～100Gy/min; The absorption dose of ionizing rays is 0.01～1 * 10 ⁵KGy, preferred 5～100kGy.Described ionizing rays irradiation process can be carried out in air, inert atmosphere or vacuum, preferably carries out in inert atmosphere and vacuum; Described ionizing rays irradiation process can be carried out at various temperatures, preferably at room temperature carries out.

In preparation method of the present invention, described Pd precursor be selected from Palladous chloride, Palladous nitrate, palladium, palladous sulfate, palladous oxide and and the organometallics of palladium in a kind of.The Pd precursor is formulated as solution in advance, uses spraying method to be carried on the carrier.

When catalyzer comprises modified component, as helping active ingredient, can separately or load on the carrier simultaneously with Pd as modified component; As the properties-correcting agent of modified component, can in the preparing carriers process, add as carrier.

In preparation method of the present invention, described free-radical scavengers is selected from least a in alcohols and the formic acid, preferably at least a in methyl alcohol, ethanol, ethylene glycol and Virahol, more preferably Virahol and ethylene glycol.In by the irradiation system, the volume ratio optional 1%～99%, preferred 5%～50% of whole liquid in the volume of free-radical scavengers and the system.

In preparation method of the present invention, not needing usually has the carrier roasting at high temperature of Pd precursor to decompose load.With the oven dry after appropriate amount of deionized water is washed 1-5 time of the carrier behind the ionizing rays irradiation, also can promptly obtain catalyzer of the present invention after the oven dry without directly oven dry of washing.Oven dry can be carried out under air atmosphere or vacuum, preferably carries out under air atmosphere.Optional 50～200 ℃ of bake out temperature, preferred 50～120 ℃.Optional 5～48 hours of drying time, preferred 5～24 hours.

Load type palladium catalyst that method of the present invention is used and preparation method thereof has the following advantages:

(1) load type palladium catalyst of the present invention is a feature with CO absorption In-situ Infrared spectrogram, guarantees that catalyst surface has the Pd site of particular types; And further with purge specific absorption peak-to-peak in 15 minutes spectrograms high be changed to feature, guarantee that catalyzer has suitable adsorptive power to specific reactants.The infrared analysis feature of catalyzer is easy to quantitatively, thereby has guaranteed that catalyzer has specific reaction preference and activity.

(2) method for preparing catalyst of the present invention need not use specific Pd precursor or crystal control agent, does not need high-temperature roasting step in the traditional method can obtain having the loaded catalyst in specific Pd site yet, and is simple, saves energy consumption.The Pd that makes catalyst surface can exist with the simple substance attitude, need not reduce before use, and have higher reactivity worth under normal conditions.

Under normal conditions, method of the present invention has high reactivity, highly selective and satisfactory stability, can long-term operation.

Description of drawings

Fig. 1 is the CO absorption In-situ Infrared spectrogram that embodiment A, B and Comparative Examples C, D, E record by method mentioned above, and four curves in each spectrogram are respectively counter sample at the infrared absorption curve of nitrogen purging in the time of 0 minute, 9 minutes, 15 minutes, 24 minutes.To purging 0 minute curve 1750～2000cm ^-1The bridge-type adsorption peak at place is carried out the swarming match, the area and the ratio of the CO bridge-type adsorption peak that calculates; And measure 1870～1930cm in 0 minute spectrogram of nitrogen purging ^-1The peak height of place's absorption peak with purge 1800～1900cm in 15 minutes spectrograms ^-1The peak height of place's absorption peak also calculates its ratio.The results are shown in Table 1.

Embodiment

Following examples are more detailed the describing for example to catalyzer of the present invention, but the present invention is not limited to these embodiment.

Embodiment 1

Get 13.5ml 10mg/ml PdCl ₂Solution after dropping 1mol/L NaOH solution transfers pH to be 5.6, is sprayed into 100.0g Al ₂O ₃Ball type carrier surface, the isopropanol water solution that uses 20ml 50%v/v with carrier wetting after, under vacuum state, use ⁶⁰In the Co gamma emitter under room temperature irradiation 15h, absorbed dose rate is 35Gy/min.Sample places baking oven behind the irradiation, dries 12h down at 80 ℃ and 120 ℃ successively, obtains described catalyst A, and its outward appearance is a grey black, and Pd content is 0.135wt%.

Embodiment 2

Get 30ml 10mg/ml PdCl ₂Solution is sprayed into the Al of 100.0g through La and K modification ₂O ₃Tooth ball type carrier surface sprays 5ml 1mol/L NaOH solution again, the isopropanol water solution that uses 20ml 50%v/v with carrier wetting after, under vacuum state, use ⁶⁰In the Co gamma emitter under room temperature irradiation 15h, absorbed dose rate is 70Gy/min.Sample places baking oven behind the irradiation, dries 12h down at 80 ℃ and 120 ℃ successively, obtains described catalyst B, and its outward appearance is a grey, and Pd content is 0.300wt%.

Comparative Examples 1

Get 13.5ml10mg/ml PdCl ₂Solution after dropping 1mol/L NaOH solution transfers pH to be 5.6, is sprayed into 100.0g Al ₂O ₃The ball type carrier surface is immersed carrier in an amount of aqueous isopropanol afterwards, is placed to reduction under the room temperature fully after (the carrier color is black by xanthochromia), place baking oven to dry 12h down at 80 ℃ and 120 ℃ successively, obtain catalyzer C, its outward appearance is a grey black, and Pd content is 0.135wt%.

Comparative Examples 2

Get 13.5ml 10mg/ml PdCl ₂Solution after dropping 1mol/L NaOH solution transfers pH to be 5.6, is sprayed into 100.0g Al ₂O ₃The ball type carrier surface places baking oven with carrier afterwards, behind oven dry 12h under 80 ℃, in 450 ℃ of roasting 8h, obtains catalyzer D under air atmosphere, and its outward appearance is a khaki color, and Pd content is 0.135wt%.

Comparative Examples 3

Get 20.0ml 10mg/ml PdCl ₂Solution uses deionized water to be diluted to 100ml, uses 1mol/L NaOH solution to regulate its pH to 3.0.Get Al ₂O ₃Ball type carrier 100g adds PdCl ₂Solution leaves standstill dipping 20min.Add Virahol 10ml afterwards in steeping fluid, the homodisperse hypsokinesis goes out excess solution, and carrier is used under vacuum ⁶⁰The Co gamma emitter is irradiation 15h under room temperature, and absorbed dose rate is 35Gy/min.Sample places baking oven behind the irradiation, dries 12h down at 80 ℃ and 120 ℃ successively, obtains described catalyzer E, and its outward appearance is a grey black, and Pd content is 0.140wt%.

Use In-situ Infrared instrument (Bruker Vertex 70), according to method mentioned above embodiment and Comparative Examples are carried out the CO adsorption experiment, measure each sample at the infrared absorption spectra of nitrogen purging in the time of 0 minute, 9 minutes, 15 minutes, 24 minutes, spectrogram is shown in Fig. 1.The absorption peak that purges 0 minute spectrogram 1750～2000cm-1 place is carried out match, calculate 1930～1990cm ^-1Place's bridge-type absorption peak and 1870～1930cm ^-1The ratio (A2/A1) of the area of place's bridge-type absorption peak; 1870～1930cm among the in-situ ft-ir figure that the measurement nitrogen purging recorded in the time of 0 minute ^-1The peak height of place's absorption peak with use 1800～1900cm among the in-situ ft-ir figure that nitrogen purging records in the time of 15 minutes instead ^-1The peak height of place's absorption peak calculates its ratio (H1/H3).Calculation result is listed in the table 1.

The infrared spectra calculation result of table 1. embodiment of the invention and Comparative Examples

Calculation result shows, the A2/A1 value of embodiment of the invention A, B is less than 0.15, and the A1/A2 value of Comparative Examples C, D, E is greater than 0.20, and this explanation embodiment A, B have crystal plane structure and the ratio that is different from Comparative Examples C, D, E.The value of the H1/H3 of embodiment of the invention A, B is less than 2, and the H1/H3 value of Comparative Examples C is 93.31, and this explanation embodiment A, B have stronger adsorptive power to carbon monoxide, and Comparative Examples C is relatively poor to the adsorptive power of carbon monoxide.Infrared test is the result show, the embodiment of the invention has the crystal face that is different from Comparative Examples to be formed and stronger reactant adsorptive power, therefore will have the reactivity worth that is different from Comparative Examples.

Use ethylene unit C-4-fraction liquid phase selective hydrogenation experimental installation that the catalytic performance of embodiment and comparative example is estimated.Adopt fixed-bed reactor, loaded catalyst is 20ml, reaction pressure 2.0MPa, temperature in is 40 ℃, hydrogen/divinyl (mol/mol)) and be 1.25: 1, the feeding liquid air speed is 20h ^-1The composition of mixed c 4 (massfraction) is a butane 7.73%, butylene 90.39%, divinyl 1.88%.Adopt each components contents in the gas chromatography determination mixed c 4.

The method of calculation of transformation efficiency of divinyl (Conversion) and butylene selectivity (Selectivity) are:

$C_4{H}_6\mathrm{Conversion}=\frac{{\left(C_4{H}_6\right)}_{\mathrm{in}}-{\left(C_4{H}_6\right)}_{\mathrm{out}}}{{\left(C_4{H}_6\right)}_{\mathrm{in}}}\&times;100\%$

$C_4{H}_8\mathrm{Selectivity}=\frac{{\left(C_4{H}_8\right)}_{\mathrm{out}}-{\left(C_4{H}_8\right)}_{\mathrm{in}}}{{\left(C_4{H}_6\right)}_{\mathrm{in}}-{\left(C_4{H}_6\right)}_{\mathrm{out}}}\&times;100\%$

Evaluation result is listed in the table 2.

The catalytic performance test result of table 2. embodiment of the invention and Comparative Examples

Sample	C 4H 8selectivity (％)	C 4H 6conversion(％)
			A	87.10	98.94
B	89.73	98.40
			C	72.43	98.40
D	68.11	98.40
			E	69.32	98.43

Evaluation result shows that embodiment of the invention A, B have good selectivity for the reaction that carbon four liquid phase selective hydrogenations generate monoolefine, and its performance obviously is better than Comparative Examples C, D, E.This explanation embodiment A, specific crystal face composition and the reactant adsorptive power of B can obviously be improved its catalytic performance.

Claims (15)

1. the selection method of hydrotreating of alkynes and diolefine in carbon four hydrocarbon streams, it is characterized in that, carbon four hydrocarbon streams that comprise alkynes and/or diolefine enter the hydrogenator that load type palladium catalyst is housed with hydrogen, and making alkynes and/or diolefin hydrogenate in the olefin stream under the mol ratio 1～10 of 10～80 ℃ of temperature ins, hydrogen and alkynes and diolefine sum and reaction pressure 0.1～4MPa is that alkene is removed; Described load type palladium catalyst comprises carrier, palladium and optional modified component, and described catalyzer adsorbs among the in-situ ft-ir figure at 40 ℃ of carbon monoxide of testing down, 1930～1990cm ^-1Place's bridge-type absorption peak and 1870～1930cm ^-1The ratio of the area of place's bridge-type absorption peak is less than 0.2.

2. method according to claim 1 is characterized in that described catalyzer in 40 ℃ of carbon monoxide absorption in-situ ft-ir figure that test down, 1930～1990cm ^-1Place's bridge-type absorption peak and 1870～1930cm ^-1The ratio of the area of place's bridge-type absorption peak is less than 0.15.

3. method according to claim 1 is characterized in that described catalyzer at 40 ℃ down behind the absorption carbon monoxide, uses 1870～1930cm among the in-situ ft-ir figure that nitrogen purging records in the time of 0 minute instead ^-1The peak height of place's absorption peak with use 1800～1900cm among the in-situ ft-ir figure that nitrogen purging records in the time of 15 minutes instead ^-1The ratio of the peak height of place's absorption peak is less than 5, preferably less than 2.

4. according to the described method of one of claim 1～3, it is characterized in that the carbon monoxide absorption infrared spectrogram of described catalyzer adopts following method to record:

A) catalyst sample with powdered form places hydrogen gas stream to be warming up to 300 ℃; Temperature rise rate is 20 ℃/min, and hydrogen flowing quantity is 10ml/min;

B) in hydrogen gas stream, be incubated 2 hours down, be cooled to 40 ℃ then in 300 ℃; Rate of temperature fall is 20 ℃/min, and hydrogen flowing quantity is 10ml/min;

C) keeping temperature is 40 ℃, feeds stream of nitrogen gas and purges 30 minutes, and nitrogen flow is 5ml/min;

D) keeping temperature is 40 ℃, feeds carbon monoxide-argon gas gas mixture, and wherein the molar content of carbon monoxide is 1%), adsorbed 30 minutes, mixed gas flow is 5ml/min;

E) keeping temperature is 40 ℃, uses nitrogen purging instead, simultaneously the in-situ ft-ir of the carbon monoxide of working sample absorption at once figure;

F) keeping nitrogen flow is 5ml/min, writes down the in-situ ft-ir figure of sample when nitrogen purging 9min, 15min, 24min respectively.

5. according to the described method of one of claim 1～3, it is characterized in that the content of palladium in the described catalyzer is 0.01～50wt% of carrier gross weight, be preferably 0.01～10wt%, more preferably 0.03～5wt%.

6. according to the described method of one of claim 1～3, the carrier that it is characterized in that described catalyzer is selected from a kind of in gac, carbon black, carbon nanotube, aluminum oxide, wilkinite, clay, diatomite, zeolite, molecular sieve, titanium oxide, magnesium oxide, silicon oxide and the polymer materials or two or more mixture in them.

7. according to the described method of one of claim 1～3, the specific surface area that it is characterized in that the carrier of described catalyzer is 1～500m ²/ g is preferably 1～200m ²/ g, more preferably 1～80m ²/ g.

8. according to the described method of one of claim 1～3, it is characterized in that described catalyzer comprises optional modified component, described modified component is selected from Bi, Sb, Pb, In, be different from least a in VIII family element, I B group element, rare earth element, alkali metal, alkali earth metal and the haloid element of palladium, and its content is 0～20wt% of carrier gross weight.

9. method according to claim 1 is characterized in that described Preparation of catalysts method comprises following steps: the solution that (1) uses spraying method will comprise the palladium precursor is carried on the carrier; (2) use the load of ionizing rays irradiation that the system of carrier, water and the free-radical scavengers of palladium precursor is arranged.

10. method according to claim 9 is characterized in that pH to 2～13 of using basic solution to regulate the palladium precursor solution in advance.

11. method according to claim 9 is characterized in that using basic solution to handle carrier before or after the supported palladium precursor, described treatment process is spraying.

12., it is characterized in that described ionizing rays is gamma-rays, X ray or electron beam according to the described method of one of claim 9～11.

13. according to the described method of one of claim 9～11, the absorbed dose rate that it is characterized in that described ionizing rays is 1～1 * 10 ⁷Gy/min, the absorption dose of described ionizing rays are 0.01～1 * 10 ⁵KGy.

14., it is characterized in that described palladium precursor is selected from the organometallics of Palladous chloride, Palladous nitrate, palladium, palladous sulfate, palladous oxide and palladium according to the described method of one of claim 9～11.

15. according to the described method of one of claim 9～11, it is characterized in that described free-radical scavengers is selected from least a in alcohols and the formic acid, preferably at least a in methyl alcohol, ethanol, ethylene glycol and Virahol, more preferably Virahol and ethylene glycol.

Images