WO1999025650A1 - Ammonia oxidation catalysts - Google Patents
Ammonia oxidation catalysts Download PDFInfo
- Publication number
- WO1999025650A1 WO1999025650A1 PCT/GB1998/003386 GB9803386W WO9925650A1 WO 1999025650 A1 WO1999025650 A1 WO 1999025650A1 GB 9803386 W GB9803386 W GB 9803386W WO 9925650 A1 WO9925650 A1 WO 9925650A1
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- WO
- WIPO (PCT)
- Prior art keywords
- meshes
- unit according
- particles
- catalyst
- cartridge
- Prior art date
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- 239000003054 catalyst Substances 0.000 title claims abstract description 82
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 62
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 31
- 238000007254 oxidation reaction Methods 0.000 title claims abstract description 29
- 230000003647 oxidation Effects 0.000 title claims abstract description 27
- 239000002245 particle Substances 0.000 claims abstract description 51
- 239000000203 mixture Substances 0.000 claims abstract description 21
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 16
- 239000010941 cobalt Substances 0.000 claims abstract description 16
- 229910052751 metal Inorganic materials 0.000 claims abstract description 15
- 239000002184 metal Substances 0.000 claims abstract description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 8
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052727 yttrium Inorganic materials 0.000 claims abstract description 7
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052742 iron Inorganic materials 0.000 claims abstract description 4
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims abstract description 4
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 12
- 229910052684 Cerium Inorganic materials 0.000 claims description 4
- 229910052777 Praseodymium Inorganic materials 0.000 claims description 4
- PUDIUYLPXJFUGB-UHFFFAOYSA-N praseodymium atom Chemical compound [Pr] PUDIUYLPXJFUGB-UHFFFAOYSA-N 0.000 claims description 4
- 229910052779 Neodymium Inorganic materials 0.000 claims description 3
- 229910052746 lanthanum Inorganic materials 0.000 claims description 3
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims description 3
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 claims description 3
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 3
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims 2
- 239000007789 gas Substances 0.000 description 15
- 239000002585 base Substances 0.000 description 11
- 230000000694 effects Effects 0.000 description 8
- 150000002739 metals Chemical class 0.000 description 7
- 238000001556 precipitation Methods 0.000 description 7
- 150000003839 salts Chemical class 0.000 description 7
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 239000010970 precious metal Substances 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 5
- 230000003247 decreasing effect Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000000919 ceramic Substances 0.000 description 4
- 238000010276 construction Methods 0.000 description 4
- 239000006260 foam Substances 0.000 description 4
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 description 4
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 239000008188 pellet Substances 0.000 description 4
- 125000006850 spacer group Chemical group 0.000 description 4
- 238000001354 calcination Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 229910000428 cobalt oxide Inorganic materials 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical compound [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 2
- ZMIGMASIKSOYAM-UHFFFAOYSA-N cerium Chemical compound [Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce] ZMIGMASIKSOYAM-UHFFFAOYSA-N 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000008187 granular material Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 150000001339 alkali metal compounds Chemical class 0.000 description 1
- 239000001099 ammonium carbonate Substances 0.000 description 1
- 235000012501 ammonium carbonate Nutrition 0.000 description 1
- 239000000908 ammonium hydroxide Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- PRORZGWHZXZQMV-UHFFFAOYSA-N azane;nitric acid Chemical compound N.O[N+]([O-])=O PRORZGWHZXZQMV-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 description 1
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 description 1
- 150000001860 citric acid derivatives Chemical class 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 150000001868 cobalt Chemical class 0.000 description 1
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000006261 foam material Substances 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 150000002603 lanthanum Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 239000001272 nitrous oxide Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000000284 resting effect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
- B01J8/0242—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly vertical
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/24—Stationary reactors without moving elements inside
- B01J19/248—Reactors comprising multiple separated flow channels
- B01J19/2495—Net-type reactors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/008—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
- B01J8/0207—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly horizontal
- B01J8/0214—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly horizontal in a cylindrical annular shaped bed
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
- C01B21/24—Nitric oxide (NO)
- C01B21/26—Preparation by catalytic or non-catalytic oxidation of ammonia
- C01B21/265—Preparation by catalytic or non-catalytic oxidation of ammonia characterised by the catalyst
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
- C01B21/24—Nitric oxide (NO)
- C01B21/26—Preparation by catalytic or non-catalytic oxidation of ammonia
- C01B21/28—Apparatus
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00796—Details of the reactor or of the particulate material
- B01J2208/00884—Means for supporting the bed of particles, e.g. grids, bars, perforated plates
Definitions
- This invention relates to ammonia oxidation catalysts
- Ammonia oxidation is widely employed in the manufacture of nitric acid and hydrogen cyanide
- ammonia is oxidised with air to nitric oxide
- hydrogen cyanide a mixture of ammonia and methane (often as natural gas) is oxidised with air
- the gas mixture is passed at an elevated temperature over a catalyst to effect the oxidation
- Side reactions such as the formation of nitrogen or nitrous oxide, are undesirable Consequently, in addition to good activity, the catalyst is required to have a good selectivity
- the catalysts employed have been platinum, sometimes alloyed with other precious metals, in the form of meshes or gauzes formed from the metal wire
- Such catalysts have good activity and selectivity but suffer from the disadvantage that not only is the catalyst very expensive, but at the temperatures encountered, the metals exhibit an appreciable volatility and so gradually the metal is lost into the gas stream
- it is well known to provide downstream means to trap the volatilised metal so that it may be recovered subsequently, because of the continual volatilisation, the life of the catalyst is short and frequent replacement is necessary
- the recovery of the metals from the downstream trap and re-fabrication of the catalyst meshes or gauzes involves a considerable allocation of working capital
- Ammonia oxidation is normally operated by passing the heated ammonia/air mixture at a high linear velocity (measured at NTP) through a wad of precious metal meshes or gauzes extending across the cross-section of the reactor
- Commercial ammonia oxidation plants usually employ reactors having a diameter in the range 0 5 to 5 m
- Linear gas velocities conventionally employed in commercial ammonia oxidation processes operating substantially at atmospheric pressure are usually in an excess of 2000 m/h, and typically are in the range 5000-10000 m/h, preferably 4000-6000 m/h
- e g up to 10 barg Jhe linear velocities are generally in the range 20000 to 50000 m/h
- the catalyst should be in a form such that it is a direct replacement for the precious metal meshes or gauzes conventionally used.
- the temperature to which the feed gas must be pre-heated in order that the oxidation process may sustain itself is termed the "blow out” temperature.
- the "blow-out” temperature is below 250°C, particularly below 150°C.
- the bed depth should be as great as possible and the particle size as small as possible.
- the pressure drop experienced by the gas as it passes through the catalyst bed This increases as the particle size of the catalyst is decreased and as the catalyst bed depth increases, and so a compromise is necessary to achieve an acceptable "blow-out" temperature while at the same time have an acceptable pressure drop.
- the bed depth should be less than 50 mm.
- the space velocity is 10 5 h '1 .
- space velocities above 10 5 hJ are normally required.
- the catalyst bed in the form of a cartridge that can replace the conventional wad of meshes or gauzes.
- an ammonia oxidation catalyst bed cartridge unit comprising a pair of retaining meshes spaced apart by less than 50 mm defining an enclosure filled with a random packed mass of particles of a composition comprising oxides of at least one metal selected from manganese, iron, nickel and cobalt , said particles having a minimum dimension of at least 0 5 mm and a maximum dimension of not more than 5 mm, the spacing between said meshes being at least 4 times, and less than 50 times, the maximum dimension of the particles
- the cartridge may comprise three spaced gauzes with the smaller particles between the middle, or intermediate, gauze and the lower gauze and the larger particles between the upper and intermediate gauzes
- the intermediate gauze is disregarded in determining the spacing of the gauzes
- the meshes which may be of a suitable heat resistant metal such as stainless steel, should have as large an aperture as is consistent with retaining the particles on the mesh
- the meshes are preferably catalytically inert
- the cartridge unit may comprise a pair of spaced apart mesh sheets dimensioned so as to fit across the reactor
- the mesh sheets may be held spaced apart by a suitable spacing member disposed round the periphery of the unit Spacing members may also be disposed at intervals across the unit
- the unit is preferably dimensioned such that it is a snug fit inside the ammonia oxidation reactor and extends across the cross-section of the reactor
- the cartridge may comprise a supporting unit, for example a grid or apertured plate dimensioned so as to fit across the reactor with a cartridge sub-unit positioned in each aperture of the plate or grid, with each sub-unit comprising a pair of spaced apart meshes with the catalyst disposed between the meshes
- the catalyst particles may be irregular granules or may be moulded or formed into geometric shapes, such as cylinders
- Preferred catalyst particles are moulded cylindrical tablets having a diameter in the range 0 5 to 4 mm and a length of 0 5 to 4 mm
- the aspect ratio of the particles, i e the ratio of the maximum dimension to the minimum dimension is preferably less than 2 Moulded particles, e g cylinders, may have one or more passages therethrough to increase the geometric surface area and to increase the bed voidage thereby reducing the pressure drop across the bed
- the bed depth, i e the spacing between the meshes is preferably 5 to 20 times the maximum dimension of the shaped particles
- the catalyst may be in a form wherein the amount of oxygen is non-stoichiomet ⁇ c This arises from the variable valency of cobalt and also of any variable valency rare earth present as part, or all, of element A
- the catalyst particles may be made by forming a finely divided powder composition into particles of the desired size by techniques such as granulation, extrusion or moulding
- the finely divided powder composition may be made by precipitation by adding a solution of soluble salts of the relevant metals to a solution of a base, e.g. ammonium carbonate or hydroxide, to precipitate the relevant metals as (basic) carbonates, hydroxides, or oxides followed by calcination to convert the precipitated compounds to the oxides
- a base e.g. ammonium carbonate or hydroxide
- the precipitation may alternatively, but less preferably, be effected by adding the base to the solution of the mixed salts.
- the active metal is cobalt
- the finely divided powder composition may be made by forming a solution of thermally decomposable salts, e.g.
- the composition may be made by mixing preformed oxides of the metals in the appropriate proportions
- the active material e.g. cobalt may be present as a coating on suitable support particles.
- a finely divided oxidic material e.g.
- ce ⁇ a may be impregnated with a solution containing a cobalt salt, and possibly also salts of other elements such as a salt of an element A, e.g a lanthanum salt, followed by decomposition of the salts.
- a supported material may be made by precipitation by precipitating the cobalt, and optionally other elements, as heat decomposable compounds on to a finely divided, e.g precipitated, oxidic support compound or compound decomposable thereto
- the composition should be calcined, e g in air, preferably at a temperature in the range 900-1200°C, before or preferably after granulating, extruding or moulding into particles of the desired size and shape
- Figure 2 is a diagrammatic cross section of a part of unit in accordance with a second embodiment of the invention
- Figure 3 is a diagrammatic cross section through an ammonia oxidation reactor incorporating a unit of the present invention
- Figure 4 is a plan view of part of a wire gauze showing cuts and fold lines
- Figure 5 is a sketch of part of a gauze as shown in Figure 4 folded to form a compartmentalised structure.
- Figure 6 is a diagrammatic cross section of a unit in accordance with a third embodiment of the invention
- Figure 7 is an enlargement of part of Figure 6 showing the configuration of the cartridge sub-units of Figure 6.
- Figure 8 is a cross section of a reactor showing the support grid and cartridge configuration of a fourth embodiment of the invention
- FIG 9 is a sketch of one of the cartridge units of Figure 8
- Figure 10 is a section through the cartridge unit of Figure 9.
- a catalyst cartridge consisting of a pair of circular stainless steel meshes 1 , 2 of diameter about 3 m having a mesh size of for example about 2 mm held spaced 20 mm apart by a spacer ring 3. Additional spacer members 4 are disposed at intervals across the cartridge. The space enclosed by the meshes and the ring is filled with random packed cylindrical catalyst tablets of 3 mm diameter and 3 mm height.
- the gauzes particularly the lower gauze, may stretch and/or sag after exposure to the prevailing operating conditions for an extended period of time.
- the catalyst particles may re-distribute themselves so that some areas of the bed have a lesser bed depth than others. This is undesirable as the process gas will preferentially pass through the portions of lesser bed depth and insufficient reaction may occur.
- the lower gauze is supported by a rigid porous structure such as tiles of a ceramic foam material.
- the upper mesh may be held firmly against the bed of catalyst particles.
- rivets 5 may be provided extending through the meshes 1 , 2 and the catalyst bed, and a spring 6 provided above the upper mesh 1 engaging with the upper mesh 1 and a cap 7 on the upper end of the rivet.
- the spring is preferably located on the upstream side of the catalyst bed, since the temperature in operation is lower than that on the downstream side of the catalyst bed.
- the rivets 5 may be provided in addition to, or instead of, the intermediate spacers 4 of the embodiment of Figure 1.
- Figure 3 there is shown an ammonia oxidation reactor 10 having an inlet port 11 and an outlet port 12. Disposed across the reactor is a catalyst cartridge 13, of the type shown in Figure 1 supported by ceramic foam tiles 14 resting on cross members 15 extending across the reactor 10.
- the lower gauze may be cut and folded to form upstanding dividing walls, preferably of height substantially equal to the desired bed depth.
- a sheet of wire gauze 16 is cut along the lines 17, 18, 19 and 20 and then folded in alternate directions along the dotted lines a-a, b-b and c-c, and along lines d-d, e-e and f-f and d'-d', e'-e' and f-f etc. to form upstanding walls 21 , 22, 23 and 24.
- the flaps e.g. 25 formed by the cuts 17 to 20 are then tack welded to the upstanding walls.
- the compartments are then filled with the particulate catalyst.
- the compartments may be of any convenient shape, e.g. square, rectangular, triangular etc.
- a catalyst bed having different size particles may be provided by providing the cartridge with three spaced gauzes with the smaller particles between the middle gauze and the lower gauze and the larger particles between the upper and middle gauzes.
- the lower gauze may be shaped to give compartments as shown in Figures 4 and 5 while the upper portion of the bed, i.e. containing the larger particles, is a continuous bed.
- FIGs 6 and 7 there is shown an alternative construction for the cartridge.
- This construction is particularly suited to embodiments where the catalyst particle size is relatively small, typically maximum dimension below 2 mm, and the bed depth shallow, e.g. less than 25 mm.
- the cartridge consists of a circular plate 26 dimensioned to fit across the reactor, e.g. in place of cartridge 13 of Figure 3.
- the plate has a plurality of circular apertures, e.g. of 100 mm diameter, spaced apart at e.g. 200 mm centres. Located within each aperture is a cartridge sub-unit 27.
- Each sub-unit consists of a plate 28 having a central aperture 29 and a pair of concentric cylindrical meshes 30, 31 , typically of length 200-300 mm, fastened at one end to the plate 28. The other end of the meshes is fastened to a closure plate 32.
- the spacing between the concentric meshes is typically 10-20 mm and the catalyst particles are disposed in the space between the two meshes 30, 31.
- a square grid of cartridge supports 33 is disposed across the reactor and a catalyst cartridge 34 is disposed in each square of the grid.
- the grid, and hence the cartridges need not be square, but may be of another polygonal shape, e.g. rectangular or triangular, in plan.
- the spaces 35 in the grid at the edges of the reactor that are not large enough to receive a cartridge 34 are closed with blanking members. Alternatively cartridges of a non-standard size may be fitted in these spaces.
- Each cartridge 34 is in the form of an inverted pyramid structure having a flange 36 by which the cartridge may be supported on the grid cartridge supports 33.
- the pyramid consists of an outer hollow square base 37 from which angle members 38 defining the outer inclined edges of the pyramid are disposed. Triangular ceramic foam tiles 39, forming the inclined faces of the pyramid, are supported by the angle members 38. These foam tiles 39 serve to support a lower, inverted pyramidal-shaped, mesh or gauze 40 attached at its upper, base, end to the outer square base 37.
- Supported within the outer hollow square base 37 by means of support brackets 41 spaced at intervals around the outer base 37 is a hollow inner square base 42 from which depends a second, inner, inverted pyramidal-shaped, mesh or gauze 43.
- a spacer member 44 is disposed at the apex of the pyramid to hold the two gauzes apart.
- the catalyst particles are disposed in the space 45 between the two gauzes.
- the space 46 between the walls of the outer and inner square bases 37 and 42 provides a reservoir for catalyst particles so that the space 45 between the gauzes 40, 43 may be kept full of catalyst particles in the event of settlement of the catalyst particles during use. It is seen that in use, the process gas flows down through the inner hollow base 42, through inner gauze 43, through the catalyst-filled space 45, and then through outer gauze 40 and the ceramic foam tile 39 as shown by the arrows.
- This form of cartridge construction facilitates replacement of the cartridges in the reactor and charging and discharging catalyst from the individual cartridges. It also has the benefit that optimum use may be made of the reactor cross sectional area while providing for a catalyst bed area substantially greater than that of the reactor cross sectional area.
- the catalyst units or cartridges of the invention may be used as a direct replacement for the conventional precious metal catalysts with essentially no modification to the ammonia oxidation process, except of course the conventional precious metal trap arrangements can be eliminated.
- the oxidation process may be operated at temperatures of 800-1000°C, particularly 850-950°C, pressures of 1 to 15 bar abs., with ammonia in air concentrations of 5-15%, often about 10%, by volume.
- Example 1 A finely divided lanthana/ceria/cobalt oxide catalyst (La:Ce:Co atomic proportions 8:2:10) was made by precipitation followed by calcination at 900°C. The resultant powder was formed into cylindrical pellets of 3 mm diameter and 3 mm height. A preheated mixture of air and ammonia containing about 10% by volume of ammonia was passed at atmospheric pressure through a bed of 40 mm depth of the pellets at various linear velocities. The preheat temperature was gradually decreased and the temperature (“blow-out" temperature) noted at which the reaction no longer was self-sustaining. While the reaction was self-sustaining the temperature of the gas mixture leaving the catalyst bed was typically about 600-650°C higher than the preheat temperature. The procedure was repeated with a catalyst bed of 20 mm depth. The results are shown in the following table.
- Example 1 The procedure of Example 1 was repeated but with the catalyst in the form of granules of diameter 0.5 mm and 2 mm, and cylindrical pellets as used in Example 1. In this example beds of various depths were used at a constant linear gas flow rate of 4500 m/h. The results are shown in the following table.
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Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU10460/99A AU733971B2 (en) | 1997-11-19 | 1998-11-06 | Ammonia oxidation catalysts |
CA002306780A CA2306780A1 (en) | 1997-11-19 | 1998-11-06 | Ammonia oxidation catalysts |
EP98952918A EP1034134A1 (en) | 1997-11-19 | 1998-11-06 | Ammonia oxidation catalysts |
NO20002522A NO20002522L (en) | 1997-11-19 | 2000-05-16 | Catalysts for ammonia oxidation |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9724310.9A GB9724310D0 (en) | 1997-11-19 | 1997-11-19 | Ammonia oxidation catalysts |
GB9724310.9 | 1997-11-19 |
Publications (1)
Publication Number | Publication Date |
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WO1999025650A1 true WO1999025650A1 (en) | 1999-05-27 |
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ID=10822227
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB1998/003386 WO1999025650A1 (en) | 1997-11-19 | 1998-11-06 | Ammonia oxidation catalysts |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP1034134A1 (en) |
AU (1) | AU733971B2 (en) |
CA (1) | CA2306780A1 (en) |
GB (1) | GB9724310D0 (en) |
NO (1) | NO20002522L (en) |
WO (1) | WO1999025650A1 (en) |
ZA (1) | ZA9810270B (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102007026712A1 (en) | 2007-06-06 | 2008-12-11 | Uhde Gmbh | Apparatus and method for catalytic gas phase reactions and their use |
WO2010046675A1 (en) * | 2008-10-20 | 2010-04-29 | Johnson Matthey Plc | Catalyst containment unit |
DE102008059930A1 (en) | 2008-12-02 | 2010-06-10 | Uhde Gmbh | Apparatus and method for catalytic gas phase reactions and their use |
EP2202201A1 (en) | 2008-12-23 | 2010-06-30 | SÜD-CHEMIE CATALYSTS ITALIA S.r.l. | Ammonia oxidation catalysts |
WO2010099970A1 (en) * | 2009-03-05 | 2010-09-10 | Uhde Gmbh | Method and apparatus for holding down catalyst particles flowing thereagainst |
DE102013004341A1 (en) | 2013-03-14 | 2014-09-18 | Thyssenkrupp Uhde Gmbh | Process for the oxidation of ammonia and suitable plant |
CN110395488A (en) * | 2019-07-30 | 2019-11-01 | 西安交通大学 | A kind of screen work Particles dispersed bed stacking method |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2148707A1 (en) * | 1970-10-01 | 1972-06-22 | Ici Ltd | Ammonia oxidation catalyst - by decomposing cobalt carbonate pellets and sintering the resulting oxide |
DE2226697A1 (en) * | 1971-05-26 | 1973-01-04 | North American Rockwell | METHOD AND DEVICE FOR HYDROGEN-OXYGEN COMBINATION |
US3948610A (en) * | 1972-06-05 | 1976-04-06 | Imperial Chemical Industries Limited | Catalyst beds for oxidizing ammonia to nitrogen oxides |
US3985681A (en) * | 1972-06-15 | 1976-10-12 | Societe Chimique De La Grande Paroisse, Azote Et Produits Chimiques | Catalyst for the oxidation of ammonia |
CN86108985A (en) * | 1986-10-04 | 1988-04-20 | 中国科学院长春应用化学研究所 | Rare earth cobaltic trioxide catalyzer for preparing nitric acid by ammonia oxidation |
US4812300A (en) * | 1987-07-13 | 1989-03-14 | Sri-International | Selective perovskite catalysts to oxidize ammonia to nitric oxide |
WO1993024229A1 (en) * | 1992-06-01 | 1993-12-09 | Pgp Industries, Inc. | Foraminous sheets for use in catalysis |
-
1997
- 1997-11-19 GB GBGB9724310.9A patent/GB9724310D0/en not_active Ceased
-
1998
- 1998-11-06 EP EP98952918A patent/EP1034134A1/en not_active Withdrawn
- 1998-11-06 WO PCT/GB1998/003386 patent/WO1999025650A1/en active IP Right Grant
- 1998-11-06 CA CA002306780A patent/CA2306780A1/en not_active Abandoned
- 1998-11-06 AU AU10460/99A patent/AU733971B2/en not_active Ceased
- 1998-11-10 ZA ZA9810270A patent/ZA9810270B/en unknown
-
2000
- 2000-05-16 NO NO20002522A patent/NO20002522L/en not_active Application Discontinuation
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2148707A1 (en) * | 1970-10-01 | 1972-06-22 | Ici Ltd | Ammonia oxidation catalyst - by decomposing cobalt carbonate pellets and sintering the resulting oxide |
DE2226697A1 (en) * | 1971-05-26 | 1973-01-04 | North American Rockwell | METHOD AND DEVICE FOR HYDROGEN-OXYGEN COMBINATION |
US3948610A (en) * | 1972-06-05 | 1976-04-06 | Imperial Chemical Industries Limited | Catalyst beds for oxidizing ammonia to nitrogen oxides |
US3985681A (en) * | 1972-06-15 | 1976-10-12 | Societe Chimique De La Grande Paroisse, Azote Et Produits Chimiques | Catalyst for the oxidation of ammonia |
CN86108985A (en) * | 1986-10-04 | 1988-04-20 | 中国科学院长春应用化学研究所 | Rare earth cobaltic trioxide catalyzer for preparing nitric acid by ammonia oxidation |
US4812300A (en) * | 1987-07-13 | 1989-03-14 | Sri-International | Selective perovskite catalysts to oxidize ammonia to nitric oxide |
WO1993024229A1 (en) * | 1992-06-01 | 1993-12-09 | Pgp Industries, Inc. | Foraminous sheets for use in catalysis |
Non-Patent Citations (1)
Title |
---|
CHEMICAL ABSTRACTS, vol. 111, no. 22, 27 November 1989, Columbus, Ohio, US; abstract no. 202883, WU, YUE ET AL: "Lathanum cerium cobalt oxide catalyst for ammonia oxidation" XP002092533 * |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102007026712A1 (en) | 2007-06-06 | 2008-12-11 | Uhde Gmbh | Apparatus and method for catalytic gas phase reactions and their use |
JP2010528840A (en) * | 2007-06-06 | 2010-08-26 | ウーデ・ゲーエムベーハー | Apparatus and method for catalytic gas phase reaction and use thereof |
US8394353B2 (en) | 2008-10-20 | 2013-03-12 | Johnson Matthey Plc | Catalyst containment unit |
WO2010046675A1 (en) * | 2008-10-20 | 2010-04-29 | Johnson Matthey Plc | Catalyst containment unit |
DE102008059930A1 (en) | 2008-12-02 | 2010-06-10 | Uhde Gmbh | Apparatus and method for catalytic gas phase reactions and their use |
EP2202201A1 (en) | 2008-12-23 | 2010-06-30 | SÜD-CHEMIE CATALYSTS ITALIA S.r.l. | Ammonia oxidation catalysts |
US8435917B2 (en) | 2008-12-23 | 2013-05-07 | Sued-Chemie Catalysts Italia S.R.L. | Ammonia oxidation catalysts |
US10125020B2 (en) | 2008-12-23 | 2018-11-13 | Sued-Chemie Catalysts Italia S.Rl. | Ammonia oxidation catalysts |
WO2010099970A1 (en) * | 2009-03-05 | 2010-09-10 | Uhde Gmbh | Method and apparatus for holding down catalyst particles flowing thereagainst |
DE102013004341A1 (en) | 2013-03-14 | 2014-09-18 | Thyssenkrupp Uhde Gmbh | Process for the oxidation of ammonia and suitable plant |
US10414654B2 (en) | 2013-03-14 | 2019-09-17 | Thyssenkrupp Industrial Solutions Ag | Method for oxidizing ammonia and system suitable therefor |
US11820653B2 (en) | 2013-03-14 | 2023-11-21 | Thyssenkrupp Industrial Solutions Ag | Method for oxidizing ammonia and system suitable therefor |
CN110395488A (en) * | 2019-07-30 | 2019-11-01 | 西安交通大学 | A kind of screen work Particles dispersed bed stacking method |
Also Published As
Publication number | Publication date |
---|---|
GB9724310D0 (en) | 1998-01-14 |
CA2306780A1 (en) | 1999-05-27 |
AU733971B2 (en) | 2001-05-31 |
NO20002522D0 (en) | 2000-05-16 |
NO20002522L (en) | 2000-05-16 |
AU1046099A (en) | 1999-06-07 |
ZA9810270B (en) | 1999-05-19 |
EP1034134A1 (en) | 2000-09-13 |
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