CN105709775B

CN105709775B - A kind of ferrum-based catalyst and its preparation method and application

Info

Publication number: CN105709775B
Application number: CN201410724382.2A
Authority: CN
Inventors: 马荣华
Original assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Priority date: 2014-12-04
Filing date: 2014-12-04
Publication date: 2018-04-10
Anticipated expiration: 2034-12-04
Also published as: CN105709775A

Abstract

The present invention discloses a kind of preparation method of ferrum-based catalyst, comprises the following steps：（1）The isometric saturation dipping organic compounds containing nitrogen aqueous solution of alumina support, dries 30 60% to the adsorbance of the organic compounds containing nitrogen aqueous solution for alumina support saturated absorption amount of solution, modified aluminium oxide supports is made after roasting；（2）Prepare the mixed aqueous solution of nickel salt and gallium salt, step（1）The modified aluminium oxide supports of preparation use the above-mentioned mixed aqueous solution of unsaturated impregnation, dry, roasting；（3）Using fountain solution impregnation steps of the unsaturated infusion process containing adsorbent（2）Carrier after roasting；（4）Step（3）Saturation co-impregnation contains the mixed solution of active metal iron, auxiliary agent manganese and auxiliary agent potassium to carrier containing adsorbent after drying, and preparation of low carbon olefines by synthetic gas catalyst is made after drying, roasting.The catalyst has the characteristics of long-term operation activity stability is high, is advantageous to commercial Application and popularization.

Description

A kind of ferrum-based catalyst and its preparation method and application

Technical field

The present invention relates to a kind of ferrum-based catalyst and its preparation method and application, relates in particular to a kind of high-activity stable Load-type iron-based preparation of low carbon olefines by synthetic gas catalyst of property and preparation method thereof.

Background technology

The low-carbon alkenes such as ethene, propylene are important basic organic chemical industry raw materials, with the development of chemical industry, its demand Amount is more and more big.So far, the approach of the low-carbon alkene such as preparing ethylene, propylene is mainly by light oil cracking process, with complete The increasingly depleted of petroleum resources in the range of ball, following energy resource structure certainly will shift.Compared with petroleum resources, coal and natural Gas resource relative abundance, develop the low-carbon alkene production technology based on coal and natural gas and have great importance.From synthesis gas （It can be converted to by natural gas and coal）The exploitation of direct preparing ethylene, propylene technology, can not only reduce to petroleum resources according to Rely, and to the chemical industrial expansion important in inhibiting in some rich gas oil starvations area.

CN1065026A discloses a kind of preparation of ethylene by use of synthetic gas method, and the preparation method for being related to catalyst is chemical precipitation Method, mechanical mixing, employ noble metal or rare metal, such as the kind chemistry of niobium, gallium, praseodymium, scandium, indium, cerium, lanthanum, ytterbium etc. more than ten Element, ethylene selectivity 65%-94%, but CO conversion ratios are very low, only 10%, 12% and 15% or so, and CO is recycled and certainly will brought The consumption of the energy, and catalyst cost is high.CN01144691.9 discloses the nano-catalytic of a kind of preparation of ethylene by use of synthetic gas, propylene Agent and preparation method thereof, the combination technique of laser pyrolysis processes combination solid phase reaction is used to be prepared for Fe₃Fe base nanometers based on C Catalyst is applied and preparing low-carbon olefin, and achieves certain effect, but due to needing practical laser technology, makes Preparation technology is comparatively laborious, and raw material uses Fe (CO)₅, the cost of catalyst is higher, and industrialization is difficult.CN03109585.2 is public Opened it is a kind of be used for preparation of ethylene by use of synthetic gas, propylene, iron/activated-carbon catalyst of butene reaction, using activated carbon as carrier, Fe As activated centre, successfully Fe is loaded on the activated carbon using vacuum impregnation technology, Fe and auxiliary agent is highly dispersed at On activated carbon, so as to improve catalytic effect, and the cost of catalyst is greatly reduced.And catalyst is in the condition without feedstock circulation Lower CO conversion ratios are up to 96-99%, and CH compounds selectivity is up to 69.5% in gas-phase product, and wherein ethene, propylene, butylene are in CHization Selectivity in compound is up to more than 68%.But activated carbon is as catalyst carrier not only bad mechanical strength but also shaping of catalyst Difficulty, the service life and stability of catalyst are influenceed, is unfavorable for commercial Application.

CN102441383A, CN101940958A, CN102441400A, CN102441384A are respectively adopted nitrogenous organic Compound solution, acid solution, the cushioning liquid of ammonium salt-containing, the mode such as hydro-thermal process impregnation is carried out to silica-gel carrier, Prepare Fe base silica gel supported synthesis gas and directly prepare light olefins catalyst, reduce Fe and SiO₂Strong phase between carrier Interaction.But the activity that above-mentioned Fe bases silica gel supported synthesis gas directly prepares the long-term operation of light olefins catalyst is steady It is qualitative still to need further to be improved.

The content of the invention

In view of the shortcomings of the prior art, the present invention provides a kind of low using aluminum oxide as the iron-based support type synthesis gas system of carrier Carbene hydrocarbon catalyst and preparation method thereof, the catalyst have the characteristics of long-term operation activity stability is high, are advantageous to industry Using and promote.

A kind of preparation method of preparation of low carbon olefines by synthetic gas catalyst, comprises the following steps：

（1）The alumina support isometric saturation dipping organic compounds containing nitrogen aqueous solution, immediately at 95-110 DEG C after dipping Lower dry 0.5-1h, it is alumina support saturated absorption amount of solution to dry to the adsorbance of the organic compounds containing nitrogen aqueous solution 30-60%, modified aluminium oxide supports are then made after aging, drying, roasting；

（2）Prepare the mixed aqueous solution of nickel salt and gallium salt, step（1）The modified aluminium oxide supports of preparation are soaked using unsaturated Stain method impregnates above-mentioned mixed aqueous solution, dries after being calcined 1h-10h at 700 DEG C ~ 1000 DEG C, is preferably roasted at 800 DEG C ~ 900 DEG C Burn 2h-8h；

（3）Using fountain solution impregnation steps of the unsaturated infusion process containing adsorbent（2）Carrier after roasting, wherein institute The adsorbent stated is the organic amine that carbon number is 2~15, and the addition of described adsorbent accounts for step（2）Vehicle weight after roasting 1% ~ 10%；

（4）Step（3）Saturation co-impregnation contains active metal iron, auxiliary agent manganese and auxiliary agent to carrier containing adsorbent after drying The mixed solution of potassium, the or else saturation spray impregnating metal auxiliary agent potassium solution, then be made after drying, roasting after drying, roasting Preparation of low carbon olefines by synthetic gas catalyst.

The inventive method step（1）Organic compounds containing nitrogen can be selected from ethanol in the middle organic compounds containing nitrogen aqueous solution One or more in amine, diethanol amine, triethanolamine and pyridine etc..Nitrogenous organic compound in the organic compounds containing nitrogen aqueous solution The weight concentration of thing is 1%-35%, preferably 5%-20%.Aging temperature is 50-95 DEG C, and preferably 60 ~ 80 DEG C, ageing time is 0.5-10h, preferably 2-5h.Drying temperature is 90-150 DEG C, drying time 0.5-36h after aging, preferably at 100-120 DEG C Dry 8-24h.Roasting is calcined 2-15 hours at 280-500 DEG C, and 3-5 hours are calcined preferably at 300-450 DEG C.

The inventive method, step（2）Middle nickel salt is the one or more in nickel chloride, nickel nitrate or nickel sulfate, and gallium salt is One or more in gallium nitrate, gallium chloride, gallium sulfate.The concentration of nickel ion is 0.1-5mol/L in mixed aqueous solution, gallium from The molar concentration of son is two times of nickel ion molar concentration.

The inventive method, step（2）Pickup is the 5-60%, preferably 20-50% of alumina support saturated absorption amount of solution. Dip time is 1-5h, and dipping temperature is 40-60 DEG C.Drying temperature is 80-150 DEG C after dipping, drying time 2-15h.

The inventive method, step（2）Middle alumina support can use existing commercial goods, can also be by existing method system It is standby.Support shapes can be spherical, bar shaped, piece type.Using spherical and bar shaped to be best.

The inventive method, step（3）Middle organic amine includes one kind in fatty amine, hydramine, acid amides, aliphatic cyclic amine or aromatic amine It is or several.Specifically include monoethyl amine, diethylamine, triethylamine, ethylenediamine, hexamethylene diamine, tert-butylamine, monoethanolamine, diethanol amine, three One kind in monoethanolamine, dimethylformamide, propionamide, butyramide, pyridine, morphine, aniline, diphenylamines, naphthalidine, dinaphthylamine Or several, the one or more preferably in diethylamine, triethylamine, morphine.

Step of the present invention（3）In, the fountain solution containing adsorbent is impregnated, is impregnated using unsaturation, preferably with unsaturation Spray, wherein the volume ratio of the dip amount and carrier saturated absorption amount of solution used in unsaturated dipping is 0.05 ~ 0.4.Dipping contains After having the fountain solution of adsorbent, can be dried under the decomposition temperature no more than selected adsorbent, can also direct impregnation contain work Property metallic iron solution, wherein drying temperature is generally 60 DEG C~150 DEG C, and 80 DEG C~120 DEG C are preferably, drying time 0.5h~ 20h, preferably 1h~6h.When spraying the fountain solution containing adsorbent, the good shower nozzle of atomizing effect should be selected, solution is uniformly divided It is scattered on alumina support.After fountain solution dipping of the dipping containing adsorbent terminates, next step can be directly carried out, may also pass through Health carries out next step again, and conditioned time is 0.5~8h.

The inventive method, step（4）The amount of middle unsaturated spray impregnating metal auxiliary agent potassium solution is molten for carrier saturated absorption The 50-90% of liquid measure, the amount of unsaturation spray impregnation aids potassium is the 40%-70% of potassium total amount in catalyst.The synthesis gas system of preparation Fe and auxiliary agent K and Mn mass ratio are respectively in light olefins catalyst（65~75）：（0.5~5）：（23~34）.Active metal is molten Liquid or compounding agent solution preparation method are known to technical staff, and its solution concentration can be adjusted by the dosage of each compound, So as to prepare the catalyst of specified activity component and auxiliary agent content.The raw material of required active component and auxiliary agent is generally salt, oxygen The compound of the type such as compound or acid, as source of iron is generally from the one or more in ferric nitrate, iron chloride, ferric sulfate, potassium resource One or more in potassium nitrate, potassium carbonate, potassium chloride, manganese source are generally from manganese nitrate or manganese chloride.

The inventive method, step（4）In add 2- in the mixed solution containing active metal iron, auxiliary agent manganese and auxiliary agent potassium The ammonium thiocyanate of 15%, preferably 5-10% in mass.Activearm can be improved using the iron salt solutions containing ammonium thiocyanate are added The decentralization divided, the active component iron catalyst of little crystal grain is prepared, so as to significantly improve the selectivity of low-carbon alkene.

The inventive method, step（4）By dry and calcination stepses after dipping, the condition of the drying and roasting is normal Rule, for example, drying steps dry 8-24 hours at 50-150 DEG C, calcination stepses are calcined 2-10 hours at 350-700 DEG C.

It is a kind of using above method prepare preparation of low carbon olefines by synthetic gas catalyst, using Fe as active component, using K and Mn as Auxiliary agent, using aluminum oxide as carrier, Fe weight percentage is 0.5%-20% in catalyst, and auxiliary agent is K and Mn, Fe in catalyst Mass ratio with auxiliary agent K and Mn is respectively（65~75）：（0.5~5）：（23~34）.

The restoring method of above-mentioned preparation of low carbon olefines by synthetic gas catalyst, is reduced using the gaseous mixture of chlorine and hydrogen, Volume content of the chlorine in gaseous mixture is 0.5-10%, preferably 1-5%, and reduction temperature is 300-450 DEG C, recovery time 3-10 Hour, pressure 0.5-2MPa.The selectivity of butylene can be improved using above-mentioned restoring method.

The inventive method uses organic compounds containing nitrogen aqueous solution saturation oxide impregnation alumina supporter first, is done through quick fraction The organic compounds containing nitrogen aqueous solution is concentrated in the internal gutter of carrier after dry, and the organic compounds containing nitrogen aqueous solution is mainly to carrier Inside carries out partially modified.Then using the mixed aqueous solution of nickel salt and gallium salt mainly to the outer surface and outside of alumina support Channel surfaces are mainly modified.The above-mentioned inside and outside duct to alumina support, which carries out uneven modification, makes alumina support Inside and outside duct physico-chemical property is significantly different, inhibits the carbochain of the low-carbon alkene of generation to increase while improving active to greatest extent And saturation is hydrogenated with, improve the conversion ratio of carbon monoxide.The inventive method makes active component iron by way of adsorbent occupy-place With manganese content by being distributed outside from interior gradually increase, potassium content in eggshell type, the selectivity of catalyst is significantly improved.The catalyst Physical and chemical performance, catalytic activity, the stability of long-term operation be obtained for raising, the combination property of catalyst protrudes.

Embodiment

The process and effect of the present invention is further illustrated with reference to embodiment, but following examples are not formed to the present invention The limitation of method.

Example 1

Weigh commercial alumina（Pore volume is 0.96ml/g, specific surface area 286.81m²/ g, saturated water adsorptive value 145ml/ G, provided by Fushun branch company of Sinopec catalyst Co., Ltd, following examples and comparative example use the aluminum oxide）, will The pyridine solution saturation that mass concentration is 5% sprays oxide impregnation aluminium, dries 1h after terminating at 95 DEG C immediately, dries pyrrole processed The adsorbance of the pyridine aqueous solution is the 60% of alumina support saturated absorption amount of solution, aging 7h at 60 DEG C, 24 is dried in 100 DEG C Hour, then it is calcined 5 hours obtained modified aluminium oxide supports at 300 DEG C.Above-mentioned modified aluminium oxide supports are sprayed using unsaturated Impregnation nickel, gallium molar concentration are respectively 0.5mol/L, 1mol/L nickel nitrate, gallium nitrate mixed aqueous solution, and dipping is warm To spend for 50 DEG C, dip time 3h, pickup is the 20% of alumina support saturated absorption amount of solution, dries 5h at 120 DEG C, 850 DEG C lower roasting 6h of roasting.The unsaturated spray dipping triethylamine aqueous solution of carrier after roasting, triethylamine aqueous solution spray volume are The 35% of the total saturated water adsorptive value of used carrier, the mass content of triethylamine is the 8% of carrier quality in triethylamine aqueous solution, spray leaching In 100 DEG C of dry 5h after stain.By final catalyst Fe content 9wt%, manganese content for 3.6wt% based on, the carrier for adsorbing triethylamine is adopted The mixed solution containing active metal iron, auxiliary agent manganese and auxiliary agent potassium is impregnated with equi-volume impregnating, 100 DEG C of dryings 16 hours, It is calcined 4 hours in 550 DEG C.It is 70 by the mass ratio of Fe, K and Mn in catalyst：3：28 meters, unsaturation spray dipping potassium nitrate are molten Liquid, pickup are the 60% of carrier saturated absorption amount of solution, and the amount of unsaturation spray impregnation aids potassium is potassium total amount in catalyst 45%.100 DEG C of dryings 16 hours, are calcined 4 hours, gained catalyst is designated as C-1 in 550 DEG C.C-1 catalyst synthesis gas is direct The reaction result for preparing low-carbon alkene is as shown in table 1.

Catalyst Evaluation Test is carried out in the continuous fixed bed reactors of high pressure, to be reduced 5 hours at pure 350 DEG C of hydrogen, pressure Power is 1.0MPa.Switching and merging gas is reacted after cooling.Reaction effluent is collected by hot trap, cold-trap respectively.Reaction condition is 280 DEG C, 1200h^-1, 2.0MPa, H₂/CO=1（Mol ratio）.C-1 catalyst synthesis gas directly prepares the 300h reactions of low-carbon alkene As a result it is as shown in table 1.

Example 2

Commercial alumina is weighed, is that 20% diethanol amine aqueous solution saturation sprays oxide impregnation aluminium by mass concentration, after terminating 0.5h is dried at 110 DEG C immediately, the dry adsorbance to the diethanol amine aqueous solution is alumina support saturated absorption amount of solution 40%, aging 4 hours at 80 DEG C, dried 8 hours in 120 DEG C, then be calcined in 400 DEG C 3 hours and obtain modified aluminas Carrier.Above-mentioned modified aluminium oxide supports using unsaturated spray impregnation nickel, gallium molar concentration be respectively 1.5mol/L, 3mol/L nickel nitrate, gallium nitrate mixed aqueous solution, dipping temperature are 60 DEG C, and dip time 2h, pickup is alumina support The 40% of saturated absorption amount of solution, 10h, 900 DEG C of roasting 4h are dried at 90 DEG C.The unsaturated spray dipping of carrier after roasting The coffee aqueous solution, aqueous morphine solution spray volume is the 10% of the total saturated water adsorptive value of used carrier, the quality of morphine in aqueous morphine solution Content is the 2% of carrier quality, health 5h after dipping is sprayed, in 90 DEG C of dry 8h.Contain by final catalyst Fe content 9wt%, manganese Measure and counted for 3.6wt%, the carrier for adsorbing morphine contains active metal iron, auxiliary agent manganese and auxiliary agent potassium using equi-volume impregnating dipping Mixed solution, 100 DEG C of dryings 16 hours, be calcined 4 hours in 550 DEG C.It is 70 by the mass ratio of Fe, K and Mn in catalyst： 3：28 meters, unsaturation spray dipping potassium nitrate solution, pickup is the 80% of carrier saturated absorption amount of solution, unsaturation spray leaching The amount of stain auxiliary agent potassium is 65% of potassium total amount in catalyst.100 DEG C of dryings 16 hours, are calcined 4 hours in 550 DEG C, gained catalysis Agent is designated as C-2, and 300h evaluation results are shown in Table 1.

Example 3

In addition to the ammonium thiocyanate that mass fraction is 5% is added in the iron nitrate aqueous solution of dipping, remaining is the same as embodiment 1, system Obtain catalyst and be designated as C-3,300h evaluation results are shown in Table 1.

Example 4

In addition to the ammonium thiocyanate that mass fraction is 10% is added in the iron nitrate aqueous solution of dipping, remaining with embodiment 1, Obtained catalysis is designated as C-4, and 300 evaluation results are shown in Table 1.

Example 5

With embodiment 1, difference is to reduce catalyst using the gaseous mixture of chlorine and hydrogen, and chlorine is mixed The volume content closed in gas is 5%, and obtained catalyst is designated as C-5, and 300h evaluation results are shown in Table 1.

Implement 6

With embodiment 1, difference is that catalyst is reduced using the gaseous mixture of chlorine and hydrogen, and chlorine is mixing Volume content in gas is 1%, and, with embodiment 1, obtained catalyst is designated as C-6 for remaining, and 300h evaluation results are shown in Table 1.

Comparative example 1

Except being respectively that 0.5mol/L, 1mol/L nickel nitrate, gallium nitrate mix using saturation spray dipping nickel, gallium molar concentration Outside Heshui solution, with embodiment 1, obtained catalyst is designated as B-1 for remaining, and 300h evaluation results are shown in Table 1.

Comparative example 2

In addition to dipping triethylamine aqueous solution is not sprayed, with embodiment 1, obtained catalyst is designated as B-2,300h evaluation knots for remaining Fruit is shown in Table 1.

The reactivity worth of the catalyst of table 1

Catalyst	CO conversion ratios（%）	Ethylene selectivity	Propylene Selectivity	Butylene selectivity
					C-1	67.6	17.5	30.6	15.8
C-2	65.0	19.0	28.8	15.3
					C-3	76.1	22.7	29.3	18.6
C-4	80.5	22.4	30.2	20.1
					C-5	71.8	16.3	24.5	26.4
C-6	68.8	15.7	22.2	26.8
					B-1	49.9	9.2	16.7	9.1
B-2	63.7	10.0	11.1	8.5

Claims

A kind of 1. preparation method of preparation of low carbon olefines by synthetic gas catalyst, it is characterised in that：Comprise the following steps：

（1）The isometric saturation of alumina support impregnates the organic compounds containing nitrogen aqueous solution, is done immediately at 95-110 DEG C after dipping Dry 0.5-1h, dry to the 30- that the adsorbance of the organic compounds containing nitrogen aqueous solution is alumina support saturated absorption amount of solution 60%, modified aluminium oxide supports are then made after aging, drying, roasting；

（2）Prepare the mixed aqueous solution of nickel salt and gallium salt, step（1）The modified aluminium oxide supports of preparation use unsaturated infusion process Impregnate above-mentioned mixed aqueous solution, dry after being calcined 1h-10h at 700 DEG C ~ 1000 DEG C；

（3）Using fountain solution impregnation steps of the unsaturated infusion process containing adsorbent（2）Carrier after roasting, wherein described Adsorbent is the organic amine that carbon number is 2~15, and the addition of described adsorbent accounts for step（2）1% of vehicle weight after roasting ~10%；

（4）Step（3）Saturation co-impregnation contains active metal iron, auxiliary agent manganese and auxiliary agent potassium to carrier containing adsorbent after drying Mixed solution, the or else saturation spray impregnating metal auxiliary agent potassium solution, then synthesis is made after drying, roasting after drying, roasting Gas producing light olefins catalyst；

Wherein, step（1）Organic compounds containing nitrogen is monoethanolamine, diethanol amine, three ethanol in the organic compounds containing nitrogen aqueous solution One or more in amine and pyridine.
2. according to the method for claim 1, it is characterised in that：Step（1）It is nitrogenous in the organic compounds containing nitrogen aqueous solution to have The weight concentration of machine compound is 1%-35%.
3. according to the method for claim 1, it is characterised in that：Step（1）Aging temperature is 50-95 DEG C, and ageing time is 0.5-10h, drying temperature is 90-150 DEG C after aging, drying time 0.5-36h, is calcined and is calcined 2-15 at 280-500 DEG C Hour.
4. according to the method for claim 1, it is characterised in that：Step（2）After drying 2h- is calcined at 800 DEG C ~ 900 DEG C 8h。
5. according to the method for claim 1, it is characterised in that：Step（2）Middle nickel salt is nickel chloride, nickel nitrate or nickel sulfate In one or more, gallium salt is gallium nitrate, gallium chloride, the one or more in gallium sulfate.
6. according to the method for claim 1, it is characterised in that：Step（2）The concentration of nickel ion is in mixed aqueous solution 0.1-5mol/L, the molar concentration of gallium ion are two times of nickel ion molar concentration.
7. according to the method for claim 1, it is characterised in that：Step（2）Pickup is that alumina support saturated absorption is molten The 5-60% of liquid measure, dip time 1-5h, dipping temperature are 40-60 DEG C, and drying temperature is 80-150 DEG C after dipping, when drying Between be 2-15h.
8. according to the method for claim 1, it is characterised in that：Step（2）Pickup is that alumina support saturated absorption is molten The 20-50% of liquid measure.
9. according to the method for claim 1, it is characterised in that：Step（3）Middle organic amine include fatty amine, hydramine, acid amides, One or more in aliphatic cyclic amine or aromatic amine.
10. according to the method for claim 1, it is characterised in that：Step（3）Middle organic amine includes monoethyl amine, diethylamine, three Ethamine, ethylenediamine, hexamethylene diamine, tert-butylamine, monoethanolamine, diethanol amine, triethanolamine, dimethylformamide, propionamide, butyryl One or more in amine, pyridine, morphine, aniline, diphenylamines, naphthalidine, dinaphthylamine.
11. according to the method for claim 10, it is characterised in that：Step（3）Middle organic amine be diethylamine, triethylamine, One or more in coffee.
12. according to the method for claim 1, it is characterised in that：Step（3）Middle fountain solution of the dipping containing adsorbent, is adopted Sprayed with unsaturation, wherein the volume ratio of unsaturated dipping dip amount used and carrier saturated absorption amount of solution for 0.05 ~ 0.4。
13. according to the method for claim 1, it is characterised in that：Step（3）After middle fountain solution of the dipping containing adsorbent, Dried under the decomposition temperature no more than selected adsorbent, drying temperature is 60 DEG C~150 DEG C, drying time 0.5h~20h.
14. according to the method for claim 13, it is characterised in that：Drying temperature is 80 DEG C~120 DEG C, drying time 1h ~6h.
15. according to the method for claim 1, it is characterised in that：Step（3）Fountain solution dipping of the middle dipping containing adsorbent After end, next step is directly carried out, or next step is carried out again by health, conditioned time is 0.5~8h.
16. according to the method for claim 1, it is characterised in that：Step（4）The preparation of low carbon olefines by synthetic gas catalysis of middle preparation Fe and auxiliary agent K and Mn mass ratio are respectively in agent（65~75）：（0.5~5）：（23~34）.
17. according to the method for claim 1, it is characterised in that：Step（4）Middle unsaturated spray impregnating metal auxiliary agent potassium is molten The amount of liquid is the 50-90% of carrier saturated absorption amount of solution, and the amount of unsaturation spray impregnation aids potassium is potassium total amount in catalyst 40%-70%。
18. according to the method for claim 1, it is characterised in that：Source of iron is one kind in ferric nitrate, iron chloride, ferric sulfate Or it is several, potassium resource is the one or more in potassium nitrate, potassium carbonate, potassium chloride, and manganese source is manganese nitrate or manganese chloride.
19. according to the method for claim 1, it is characterised in that：Step（4）Contain active metal iron, auxiliary agent manganese and auxiliary agent The ammonium thiocyanates of 2-15% in mass are added in the mixed solution of potassium.
20. according to the method for claim 19, it is characterised in that：Step（4）Contain active metal iron, auxiliary agent manganese and auxiliary agent The ammonium thiocyanates of 5-10% in mass are added in the mixed solution of potassium.
21. according to the method for claim 1, it is characterised in that：Step（4）By dry and calcination stepses after dipping, do Dry step dries 8-24 hours at 50-150 DEG C, and calcination stepses are calcined 2-10 hours at 350-700 DEG C.
A kind of 22. preparation of low carbon olefines by synthetic gas catalyst prepared using claim 1-21 either method, it is characterised in that：Should Catalyst is using Fe as active component, and using K and Mn as auxiliary agent, using aluminum oxide as carrier, Fe weight percentage is in catalyst 0.5%-20%, Fe and auxiliary agent K and Mn mass ratio is respectively（65~75）：（0.5~5）：（23~34）.
23. the restoring method of catalyst described in claim 22, it is characterised in that：Gone back using the gaseous mixture of chlorine and hydrogen Original, volume content of the chlorine in gaseous mixture are 0.5-10%, and reduction temperature is 300-450 DEG C, and the recovery time is 3-10 hours, Pressure is 0.5-2MPa.
24. restoring method according to claim 23, it is characterised in that：Volume content of the chlorine in gaseous mixture is 1- 5%。