Catalyst for synthesis of hydrocarbons from co and h2
FIELD: petrochemical process catalysts.
SUBSTANCE: fischer-Tropsch process catalyst constituted by cobalt deposited on aluminum metal may additionally contain promoters selected from oxides ZrO2, La2O3, K2O and metals Re, Ru, Pd, and Pt.
EFFECT: increased heat conductivity and selectivity.
2 cl, 2 tbl, 2 ex
The present invention relates to the production of catalysts, in particular catalysts for the synthesis of aliphatic hydrocarbon, C5-C25from carbon monoxide and hydrogen (synthesis Fischer-Tropsch). The resulting products are components of motor fuels (gasoline and diesel), as well as intended for further processing in the processes of chemistry.
Known catalyst for the synthesis of aliphatic hydrocarbon, C5-C25from carbon monoxide and hydrogen Fe-K/Al2O3/Al. Conversion of CO at 260° and a pressure of 8 MPa does not exceed 23% .
The main disadvantage of the catalyst of this type is low activity in the synthesis of hydrocarbons From5-C25from CO and H2.
Also known catalyst for synthesis of hydrocarbons From5-C25from CO and H2representing With the media Al2O3prepared by impregnation , with the following composition, wt.%: 10-30 With and 70-90 Al2O3. Before the synthesis of the catalyst restore at 500° C for 15 hours In his presence when the conversion of CO to 15% of a mixture of 2H2+CO liquid hydrocarbons was formed with a selectivity of 63%. The main disadvantages of this catalyst are the need for long-term recovery and presence as a carrier of aluminum oxide, obladaushi what about the poor heat conductivity, which leads to rapid loss of selectivity for target products and stability.
The closest is the catalyst for synthesis of hydrocarbons, C5-C25from CO and H2composition, wt.%: 1-30 of Co, 0.01 To 5 Ru or Mo or TA, from 65 to 98,95 Al2O3. The catalyst is prepared by impregnation of the support with aqueous solutions of appropriate compounds of Co and Ru or Mo or TA, followed by drying at 100-120° and calcination in a stream of air at 400° C. Restoration carried out for 12 h at 350° With a mixture of H2and N2and 12 h net H2. The synthesis conditions: 220° C, 2 MPa, H2/CO=2. As a result, when the conversion of CO 55-70% of the hydrocarbon, C5-C25was formed with a selectivity of 64.5-74,8%. The main disadvantages of this catalyst is its low thermal conductivity (28 W/m· ° C))associated with part of the oxide catalyst carrier, and a lengthy rehabilitation process.
The aim of the invention is to provide a catalyst for synthesis of hydrocarbons From5-C25from CO and H2possessing good thermal conductivity and high selectivity.
The goal is to reach the proposed catalyst for synthesis of hydrocarbons From5-C25from CO and H2representing the cobalt on the media - the metal powder of aluminum, the next time the content is assured components, wt.%:
The proposed catalyst may contain additives selected from the group of metal oxide (ZrO2or La2O3or K2O) in an amount of 1-3 wt.% or metals (Re, or Ru, or Pd, or Pt) in the amount of 0.5 wt.%.
The hallmark of this catalyst is used as a carrier of aluminum metal. thermal conductivity of aluminum is 238 W/m· ° (C)and aluminium oxide - 28 W/m· °). The result is the catalyst more resistant to local overheating and, therefore, more stable.
Improved heat transfer in the presence of a catalyst Co/Al compared with catalyst Co/Al2O3confirmed experimentally the size of the hysteresis loop observed in the coordinates of the KCO-T with successive increase and decrease of the synthesis temperature. In the first case, the CO conversion 60% the width of the loop is 1° s, the second - 8° C. a Stationary mode of operation of the catalyst Co/Al is set for 30 min, and the catalyst Co/Al2O3within 90 min, which increases the stability of the catalyst.
According to the invention the catalyst samples prepared by impregnation of the carrier with an aqueous solution of cobalt nitrate with subsequent drying in a water bath and calcination in a stream of air at 450B0; C for 1 h
Sample preparation of the catalyst.
The catalyst composition, wt.%: 30 Co and 70 Al is prepared in two stages. On the first of 12.7 g of cobalt nitrate dissolved in 15 ml of the distillated water. The resulting solution was poured with stirring, 12 g of the aluminum powder GOST 9849-74. Stand 15 min and dried in a water bath with constant stirring 1 h and Then the resulting powder was mixed with quartz (particle diameter quartz - 3-4 mm) in a volume ratio of 1:1 and calcined in air flow (volumetric rate of not less than 1000 h-1) at 450° C for 1 h, the Sample is cooled to room temperature and separated from the quartz.
In the second stage of 12.7 g of cobalt nitrate Co(NO3)2·6N2O dissolved in 15 ml of distilled water and poured to the calcined sample with stirring. Stand 15 min and dried on a water bath for 1 hour
Get the catalyst composition, wt.%:
The preparation of the catalyst composition, wt.%: 30, 0,5 Pd and 69.5 Al, carried out in 3 stages. On the first take 12 grams of the aluminum powder, 0.1 g of PdCl215 ml of distilled water. The palladium chloride is dissolved in hot water. The solution is poured with stirring to aluminum powder. Leave for 15 minutes, Dried in a water bath with constant stirring for 1 h Then the resulting powder was mixed with quartz (di is m particles of quartz - 3-4 mm) in a volume ratio of 1:1 and calcined in air flow (volumetric rate of ~1000 h-1) at 450° C for 1 h, the Sample is cooled to room temperature and separated from the quartz.
In the second stage take 12.7 g of Co(NO3)2·6H2O and 15 ml of distilled water. The cobalt nitrate dissolved in water. The solution is poured with stirring to the calcined sample. Leave for 15 minutes, Dried in a water bath with constant stirring for 1 h Then the resulting powder was mixed with quartz (particle diameter quartz - 3-4 mm) in a volume ratio of 1:1 and calcined in air flow (volumetric rate of ~1000 h-1) at 450° C for 1 h, the Sample is cooled to room temperature and separated from the quartz.
In the third stage, 12.7 g of cobalt nitrate Co(NO3)2·6H2O dissolved in 15 ml of distilled water and poured to the calcined sample with stirring. Stand 15 min and dried on a water bath for 1 hour
Get the catalyst composition, wt.%:
The preferred conditions for synthesis are the following: a temperature of 190-220° C, the pressure is atmospheric, the volumetric rate of synthesis-gas - 100 h-1. Testing of the catalyst is carried out by loading into the reactor 16-24 g of catalyst mixed with quartz in a volume ratio of 3:1. Then the sample is srabatyvayut hydrogen at a temperature of 400-600° C for 1-5 h with a bulk velocity - 100-3000 h-1. After you restore a portion of the catalyst is treated synthesis gas with a gradual increase in temperature from 160 to 230° 10° With every 5 h of treatment. The synthesis gas has a composition, mol.%: 66-68 H2and 32-34 CO. The process is conducted in a stationary catalyst bed.
Catalyst Co/Al has been extensively field tested in laboratory conditions. The results are given in table 1 and 2.
The test results catalyst Co/Al
|The binder content, wt.%||10||30||50||30||30|
|Conditions repair: the volumetric rate of hydrogen, h-1||100||100||100||3000||3000|
|The temperature of the synthesis, °||210||210||200||190||190|
|The CO conversion, %||56||64||69||74||58|
|The release of hydrocarbons, the/m 3||113||125||149||153||118|
|of them With5-C25, g/m3||88||85||103||118||94|
|Selectivity for hydrocarbons5-C25, %||75||70||70||75||79|
The results of the tests of the catalyst 30%/promoter/Al (Conditions repair: the volumetric rate of hydrogen - 3000 h-1temperature-450° C, duration - 1 hour)
|The content of the promoter, wt.%||3||1||1,5||0,5||0,5||0,5||0,5|
|The temperature of the synthesis, °||190||190||210||170||170||170||170|
|The CO conversion, %||62||67||62||62||65||65||56||The release of hydrocarbons, g/m3||129||135||124||128||136||130||113|
|of them C5-C25, g/m3||108||115||110||117||120||110||101|
|Selectivity for hydrocarbons5-C25, %||83||85||85||91||88||85||90|
As seen from the above examples, the proposed catalyst allows you to:
- to increase the activity and selectivity in the synthesis of hydrocarbons, C5-C25from CO and H2: at atmospheric pressure and low temperature conversion of CO is 50-75%, the yield of hydrocarbons, C5-C25- 85-120 g/m3and the selectivity of their education - 70-91%;
- by improving heat removal from the reaction zone to increase the stability of the catalyst.
Sources of information
1. Tikhov S.F., Sadykov V.A., Potapova Yu.A. et al. // Studies in Surface Science and Catalysis (Preparation of Catalysts VII). 1998. V.118. P.797-806.
2. Pankin, GV, Chernavskii P.A., Lermontov A.S., Lunin V.V. // Petrochemicals. 2001. So 41. No. 5. S-353.
3. U.S. patent 6235798, class B 017 J 023/40, C 07 C 027/00, published. 2001 (prototype).
1. Catalyst for the synthesis of aliphatic hydrocarbons5-C25from CO and Hsub> 2containing cobalt on the carrier, characterized in that as the carrier is used, the metal powder of aluminum and the catalyst has the following composition, wt.%:
Al the Rest
2. The catalyst according to claim 1, characterized in that it further contains an additive promoter selected from the group of metal-oxide - ZrO2or La2O3or K2O - or metal - Re, or Ru, or Pd, or Pt, and the catalyst has the following composition, wt.%:
Additive promoter of 0.5-3
Al the Rest
FIELD: hydrocarbon manufacturing.
SUBSTANCE: natural gas is brought into reaction with vapor and oxygen-containing gas in at least one reforming zone to produce syngas mainly containing hydrogen and carbon monoxide and some amount of carbon dioxide. Said gas is fed in Fisher-Tropsh synthesis reactor to obtain crude synthesis stream containing low hydrocarbons, high hydrocarbons, water, and unconverted syngas. Then said crude synthesis stream is separated in drawing zone onto crude product stream containing as main component high hydrocarbons, water stream, and exhaust gas stream, comprising mainly remained components. Further at least part of exhaust gas stream is vapor reformed in separated vapor reforming apparatus, and reformed exhaust gas is charged into gas stream before its introducing in Fisher-Tropsh synthesis reactor.
EFFECT: increased hydrocarbon yield with slight releasing of carbon dioxide.
7 cl, 3 dwg, 1 tbl, 5 ex
FIELD: selective oxidation of carbon monoxide in hydrogen-containing stream.
SUBSTANCE: invention relates to method for selective oxidation of carbon monoxide to carbon dioxide in raw material containing hydrogen and carbon monoxide in presence of catalyst comprising platinum and iron. Catalyst may be treated with acid. Certain amount of free oxygen is blended with mixture containing hydrogen and carbon monoxide to provide second gaseous mixture having elevated ratio of oxygen/carbon monoxide. Second gaseous mixture is brought into contact with catalyst, containing substrate impregnated with platinum and iron. Carbon monoxide in the second gaseous mixture is almost fully converted to carbon dioxide, i.e. amount of carbon monoxide in product stream introduced into combustion cell is enough small and doesn't impact on catalyst operation characteristics.
EFFECT: production of hydrogen fuel for combustion cell with industrial advantages.
13 cl, 1 tbl, 4 ex
FIELD: catalytic chemistry.
SUBSTANCE: the invention is dealt with the fields of catalytic chemistry. The invention offers a predecessor of the cobaltic catalyst, which contains a catalyst carrier impregnated with cobalt. All the restorable cobalt is present in the carrying agent in the form of a sustained cobalt oxide in accordance with a block formula CoOaHb, in which a ≥ 1.7 and b ≥ 0. The invention also offers alternatives of the method of preparation of the predecessor of the cobaltic catalyst. The technical result is production of a cobaltic catalyst with a higher activity.
EFFECT: the invention ensures production of a cobaltic catalyst with a higher activity.
20 cl, 10 ex, 12 tbl, 10 dwg