CN1147570C - Grading scheme of hydrocatalyst - Google Patents

Abstract

The present invention relates to a grading method of a hydrotreatment catalyst for residual oil. In the method, the grading of a desulfurization catalyst and denitrification catalyst bed layers is changed in the principle that the catalyst activity is gradually reduced in the material flow direction, and the space between the bed layers is additionally provided with a transitional catalyst bed layer so that the temperature rise of each bed layer of the catalyst is stable. Compared with the traditional method, the method has the advantages of high catalyst stability, easy control of the temperature rise of each catalyst bed layer, no hot spot occurrence in a reaction zone, and hydrogen consumption reduction.

Description

A kind of grading method of hydrotreating catalyst

The present invention relates to the grating of a kind of grading method of hydrotreating catalyst, particularly catalyst for hydrotreatment of residual oil, be particularly useful for residue fixed-bed hydrotreatment process.

As everyone knows, industrial residual hydrocracking general, the most sophisticated most widely used technology is fixed bed.In fixed bed residual hydrocracking technology; each major company all uses catalyzer grading loading technology as UOP, Xue Fulong, associating oil, IFP etc. in the world; promptly use two or more difference in functionality catalyzer, comprising hydrogenation protecting agent, Hydrodemetalation catalyst, Hydrobon catalyst, hydrodenitrogenation catalyst and hydrocracking catalyst etc.The filling order of catalyzer in reactor generally is that stock oil is contacted with hydrogenation protecting agent, hydrodemetallation (HDM) agent, hydrogenating desulfurization agent, hydrodenitrification agent, hydrocracking catalyst successively.But because the residual oil of different crude oils has it separately, add that residual oil takes off the complicacy of impurity reaction, up to now, the hydrotreatment of residual oil is also in exploration.

As everyone knows, reaction in the residual hydrocracking process mainly comprises the hydrocracking of the saturated and various hydro carbons of hydrogenating desulfurization, hydrodenitrification, hydrodemetallation (HDM), alkene and aromatic hydrogenation, as a whole, the residual hydrogenation reaction is thermopositive reaction, the hydrodemetallation (HDM) reaction comparatively relaxes, and hydrogenating desulfurization and hydrodenitrification reaction are comparatively strong, are strong exothermal reactions, therefore in the fixed bed tandem process, desulfurization, denitrification catalyst bed reaction temperature rising are excessive.Each major company is as UOP in the world, Xue Fulong, associating oil, IFP etc. are in desulfurization, the denitrification catalyst bed uses single catalyst system, there is the temperature the end of than the refinery for guaranteeing next reactor inlet, have to inject a large amount of cold hydrogen to beds, sometimes even by the amount of falling prevent that temperature rise is too high, so both increased the cold hydrogen amount of device, also increased stock oil cracking reaction and coking reaction, increased the hydrogen consumption of device, particularly use initial stage and latter stage at catalyzer, catalyzer uses initial activity higher, hydrogenation reaction is more violent, catalyzer uses the later stage, and the higher hydrogenation reaction of temperature of reaction is violent equally, the heat cracking reaction when adding high temperature, the beds coking is serious, usually forces device to be stopped work.

CN1197105A discloses a kind of method of hydrocarbon raw material of hydrotreatment containing metal pollutent, and this method is in the presence of hydrogen, and raw material is contacted with one or more beds in first catalyzer, second catalyzer, the 3rd catalyzer.Various catalyst properties, the function difference.In fact, along the logistics direction, catalyst activity becomes greatly gradually, and the aperture reduces gradually, is the first demetalization of standard, desulfurization again, the hydrotreatment process of last denitrogenation.Evidence, the shortcoming of this classification filling method are that second catalyzer, the 3rd beds temperature rise are excessive, and cold hydrogen requirement is big, and treatment capacity can't improve.

The present invention seeks to overcome the defective of conventional art, a kind of catalyst grade prescription case that is more suitable in residual hydrocracking is provided, the effectively control catalyst bed temperature rise of this scheme reduces the hydrogen consumption, prolongs catalyzer work-ing life.

Evidence, when adopting two or more catalyzer, because the catalyst activity difference, certain zone forms localized hyperthermia between bed easily, it is usually said focus, after focus occurred, sedimentation of coke increased relatively, makes liquid flow rate low, thereby improved transformation efficiency, and then make on the catalyzer sedimentation of coke more serious, so the present invention adopts the mixing bed of transition, this bed can effectively suppress focus and emerge.

Principal character of the present invention just is: desulfurization, denitrification reaction are divided into two or more beds, and set up a mixed transition bed between bed.

Be that example is described in detail reaction zone is divided into two beds below: promptly desulfurization, denitrification reaction are divided into two beds, be respectively the first desulfurization bed, the second desulfurization bed and the first denitrogenation bed and the second denitrogenation bed; And between the first desulfurization bed and the second desulfurization bed, set up a transition desulfurization bed, between the first denitrogenation bed and the second denitrogenation bed, set up a transition denitrogenation bed.

Wherein the content of active ingredient is in the first desulfurization bed catalyzer: MoO ₃16.0-22.0m% is preferably 18.0-20.0m%; NiO 4.0-7.0m% is preferably 4.5-5.5m%, P1.5-2.5m%; The second desulfurization bed catalyst activity component concentration is: MoO ₃12.0-18.0m% is preferably 14.0-18.0m%; NiO3.0-6.0m% is preferably 3.5-4.5m%, P1.5-2.5m%.

The first denitrogenation bed activity of such catalysts component concentration is: MoO ₃Content is generally 20.0-26.0m%, is 22.0-24.0m% preferably, and NiO content is generally 8.0-10.0m%, is 8.5-9.5m% preferably; The second denitrogenation bed catalyzer MoO ₃Content is generally 16.0-22.0m%, is 18.0-20.0m% preferably, and NiO content is generally 6.0-8.0m%, is 6.5-7.5m% preferably.

The filling ratio of the said first desulfurization bed and the second desulfurization bed catalyzer is 80v%/20v%-50v%/50v%, be preferably 70v%/30v%-60v%/40v%, the filling ratio of the first denitrogenation bed and the second denitrogenation bed catalyzer is 80v%/20v%-50v%/50v%, is preferably 70v%/30v%-60v%/40v%.

Transition desulfurization bed accounts for the 2-5v% of whole desulfurization catalyst bed, the catalyzer that wherein contains the first desulfurization bed and the second desulfurization bed, the blending ratio of two kinds of catalyzer is 50v%/50v%-20v%/80v%, is preferably 30v%/70v%-40v%/60v%; Said transition denitrogenation bed accounts for the 2-5v% of whole denitrogenation bed, the catalyzer that wherein contains the first denitrogenation bed and the second denitrogenation bed, the blending ratio of two kinds of catalyzer is 50v%/50v%-20v%/80v%, is preferably 30v%/70v%-40v%/60v%.

It is carrier that described desulfurization, denitrification catalyst can adopt with porous inorganic oxide such as aluminum oxide, the oxide compound of group vib and/or VIII family metal oxide such as W, Mo, Co, Ni etc. is an active ingredient, the catalyzer that optionally adds other various auxiliary agents such as P, Si, elements such as F, B is for example by serial heavy, the residual oil hydrocatalyst of the FZC that Fushun Petrochemical Research Institute pilot scale base produces and first fertilizer plant of Qilu Petrochemical company produces.

Following for sake of convenience to use two kinds of catalyzer to be specifically addressed as example combined catalyst filling figure.

Fig. 1 is the filling scheme of desulfurization catalyst bed of the present invention.Fig. 2 is the filling scheme of denitrification catalyst bed.As seen from the figure, A, E, F, J are the inert substance bed; B, C, D are the desulfurization catalyst bed, and G, H, I are the denitrification catalyst bed, and wherein C, H are the transition bed.

Described A, E, F, J be any traditional filling method for the inert substance bed can adopt, and inert substance can be selected the solid porcelain ball, porcelain ring, inertia aluminum oxide of resistant to elevated temperatures different shape etc. for use, requires to have low surface area, does not have any catalytic performance.The adjacent catalyst volume of filling principle its volume ratio of general requirement is big, guarantees not mutual seepage between protective material and the catalyzer.

It is carrier that described B, D bed desulfurization catalyst adopt with porous inorganic oxide such as aluminum oxide, and Mo, Ni, P are the catalyzer of active ingredient, and the optional cylinder of shape, Herba Galii Bungei, trifolium, sphere etc. are cylinder bar, Herba Galii Bungei preferably; The pore volume of catalyzer is generally 0.3-0.5ml/g, is 0.35-0.45ml/g preferably; Specific surface area is generally 120-200m ²/ g is 140-180m preferably ²/ g; Wherein B bed activity of such catalysts component is than D bed catalyzer height, B bed catalyzer MoO ₃Content is generally 16.0-22.0m%; Be 18.0-20.0m% preferably, NiO content is generally 4.0-7.0m%, is 4.5-5.5m% preferably, and P content is 1.5-2.5m%; D bed catalyzer MoO ₃Content is generally 12.0-18.0m%, is 14.0-18.0m% preferably, and NiO content is generally 3.0-6.0m%, is 3.5-4.5m% preferably, and P content is 1.5-2.5m%.

It is carrier that described G, I bed denitrification catalyst adopt with porous inorganic oxide such as aluminum oxide, Mo, Ni, is the catalyzer of active ingredient, and the optional cylinder of shape, Herba Galii Bungei, trifolium, sphere etc. are cylinder bar, Herba Galii Bungei preferably; The pore volume of catalyzer is generally 0.3-0.5ml/g, is 0.35-0.45ml/g preferably; Specific surface area is generally 160-260m ²/ g is 180-240m preferably ²/ g; Wherein G bed activity of such catalysts component concentration is than H bed catalyzer height, G bed catalyzer MoO ₃Content is generally 20.0-26.0m%, is 22.0-24.0m% preferably, and NiO content is generally 8.0-10.0m%, is 8.5-9.5m% preferably; I bed catalyzer MoO ₃Content is generally 16.0-22.0m%, is 18.0-20.0m% preferably, and NiO content is generally 6.0-8.0m%, is 6.5-7.5m% preferably.

The filling ratio of described B, D beds is generally 80v%/20v%-50v%/50v%, is 70v%/30v%-60v%/40v% preferably.

The filling ratio of described G, I beds is generally 80v%/20v%-50v%/50v%, is 70v%/30v%-60v%/40v% preferably.

Described C transition bed catalyzer is the mixing bed of catalyst B and D, this bed accounts for the 2-5v% of whole desulfurization catalyst bed, wherein the blending ratio of catalyst B and catalyzer D is generally 50v%/50v%-20v%/80v%, is 30v%/70v%-40v%/60v% preferably.

Described H transition bed catalyzer is the mixing bed of catalyzer G and I, this bed accounts for the 2-5v% of whole denitrification catalyst bed, wherein the blending ratio of catalyzer G and catalyst I is generally 50v%/50v%-20v%/80v%, is 30v%/70v%-40v%/60v% preferably.

The advantage of this method is: it is more reasonable that desulfurization, the temperature rise of denitrification catalyst bed are distributed; 2) set up a transition beds, prevent that focus from appearring in reaction zone; 3) greatly reduce device hydrogen consumption; 4) slow down the carbon deposit of beds, reduced bed pressure drop; 5) prolonged life of catalyst.

Embodiment 1

On the testing apparatus that three reactor 3 liters are arranged, adopt the complete series catalyst for hydrotreatment of residual oil of Fushun Petrochemical Research Institute's exploitation to carry out the evaluating catalyst test.Each anti-top inert bed adopts inertia porcelain ring, the bottom inert bed adopts inertia alumina balls and porcelain ring, the filling situation of each anticatalyzer is: one instead loads CEN-2, CEN-4, FZC-16, CEN-5, CEN-6 from top to bottom, and filling ratio (V) is: 1: 1.5: 2.2: 2.4: 13; Two instead load ZTS01, (ZTS01+ZTS02), ZTS02 from top to bottom, and filling ratio (V) is 10: 1: 10:, wherein the ratio of transition layer ZTS01, ZTS02 is 50v%: 50v%; Three instead load ZTN01, (ZTN01+ZTN02), ZTN02 from top to bottom, and filling ratio (V) is 10: 1: 10, and wherein the ratio of transition layer ZTN01, ZTN02 is 50v%: 50v%; The filling ratio (V) of three reactors is 45: 20: 35.Above-mentioned inertia porcelain ring, inertia alumina balls, CEN-2, CEN-4, FZC-16, CEN-5, CEN-6 catalyzer are to be produced by Fushun Petrochemical Research Institute pilot scale base, ZTS01, ZTS02, ZTN01 and ZTN02 are produced by first fertilizer plant of Qilu Petrochemical company, and the main physico-chemical property of catalyzer sees Table 2.The standard operation condition of device is: reaction pressure 15.7MPa, and 385 ℃ of temperature of reaction, hydrogen-oil ratio is 758 (v/v), volume space velocity 0.2h during liquid ^-1Subtracting slag with blended Iran is raw material, and the main character of stock oil is listed in following table 3.In the time of 1000,2000,3000 hours, device is tested with stock oil in the table 3 under the standard operation condition in the steady running of slag input oil, and test-results sees Table 4.

Table 2: the main physico-chemical property of catalyst system therefor of the present invention

Catalyzer		Shape	Pore volume, ml/g	Specific surface, m 2/g	Tap density, g/ml	Metal is formed, m%
									NiO	MoO 3	P
						Protective material	CEN-2	Ellipsoid				1.18	150	0.41	2.5	-
CEN-4	Spherical	1.22	133	0.42	2.0				-
							FZC-16	Spherical			0.49	156	0.76	2.5	-
Metal remover	CEN-5	Cylinder	0.66	136	0.55				3.1	-
						CEN-6	Cylinder	0.62			150	0.60	3.1	8.9
	Sweetening agent	ZTS-01	Cylinder	0.38	145				0.85	19.0						5.0	2.0
ZTS-02						Cylinder	0.39	145			0.85	15.5	4.0	1.8
		Denitrfying agent	ZTN-01	Cylinder	0.40				220	0.85					22.5	9.1	-
ZTN-02	Cylinder					0.40	220	0.85			19.0	7.2	-

Table 3: test raw material oil main character

Density, Kg/m3	981.6
		S，m％	3.12
N，m％	0.30
		Carbon residue, m%	13.49
(Ni+V)，μg/g	100.8
		Four components, m%
Stable hydrocarbon	30.1
		Aromatic hydrocarbon	47.5
Colloid	19.2
		Bituminous matter	3.2

Table 4: test-results

Processing condition:
										Reaction pressure, MPa	15.7
Temperature of reaction, ℃	385
										Hydrogen-oil ratio, v/v	758
Volume space velocity, h -1	0.20
										Runtime, h	1000			2000			3000
Hydrogen consumption (to fresh feed) m%	1.60			1.58			1.57
										Test-results:
Reactor	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-
										The bed temperature rise, ℃	10	20	16	9	18	15	8	16	14
Desulfurization degree, %	46.0	27.6	16.0	45.5	26.6	17.1	45.1	25.9	18.0
										Denitrification percent, %	0.82	29.5	26.7	0.65	29.0	26.3	0.45	28.0	25.9
Take off carbon yield, %	33.5	13.1	18.3	32.9	12.8	18.0	32.6	12.3	17.8
										Take off (Ni+V) rate, %	77.4	2.40	7.22	76.5	2.21	7.46	75.4	1.92	7.90
Decreasing ratio refers to each anti-clean decreasing ratio that generates oil to corresponding impurity in the stock oil that device advances

Embodiment 2

On the testing apparatus that three reactor 3 liters are arranged, adopt catalyzer, standard test condition, the stock oil evaluation test identical with embodiment 1.Each anti-inert bed filling, anticatalyzer filling are instead loaded ZTS01, (ZTS01+ZTS02), ZTS02 from top to bottom with embodiment 1, two, and filling ratio (V) is 60: 2.5: 40, and wherein the ratio of transition layer ZTS01, ZTS02 is 60v%: 40v%; Three instead load ZTN01, (ZTN01+ZTN02), ZTN02 from top to bottom, and filling ratio (V) is 60: 2.5: 40, and wherein the ratio of transition layer ZTN01, ZTN02 is 60v%: 40v%; The filling ratio (V) of three reactors is 45: 20: 35.In the time of 1000,2000,3000 hours, device is tested with stock oil in the table 3 under the standard operation condition in the steady running of slag input oil, and test-results sees Table 5.

Table 5: test-results

Processing condition:
										Reaction pressure, Mpa	15.7
Temperature of reaction, ℃	385
										Hydrogen-oil ratio, v/v	758
Volume space velocity, h -1	0.20
										Runtime, h	1000			2000			3000
Hydrogen consumption (to fresh feed) m%	1.60			1.59			1.58
										Test-results:
Reactor	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-
										The bed temperature rise, ℃	10	23	18	9	20	17	8	18	16
Desulfurization degree, %	46.0	28.1	16.4	45.5	27.1	17.6	45.1	26.3	18.5
										Denitrification percent, %	0.82	30.0	27.2	0.65	29.3	26.8	0.45	28.4	26.4
Take off carbon yield, %	33.5	13.6	18.8	32.9	13.2	18.5	32.6	12.8	18.3
										Take off (Ni+V) rate, %	77.4	2.48	7.32	76.5	2.25	7.56	75.4	1.98	7.96
Decreasing ratio refers to each anti-clean decreasing ratio that generates oil to corresponding impurity in the stock oil that device advances

Embodiment 3

On the testing apparatus that three reactor 3 liters are arranged, adopt catalyzer, standard test condition, the stock oil evaluation test identical with embodiment 1.Each anti-inert bed filling, anticatalyzer filling are instead loaded ZTS01, (ZTS01+ZTS02), ZTS02 from top to bottom with embodiment 1, two, and filling ratio (V) is 80: 3.0: 20, and wherein the ratio of transition layer ZTS01, ZTS02 is 80v%: 20v%; Three instead load ZTN01, (ZTN01+ZTN02), ZTN02 from top to bottom, and filling ratio (V) is 50: 3.0: 50, and wherein the ratio of transition layer ZTN01, ZTN02 is 50v%: 50v%; The filling ratio (V) of three reactors is 45: 20: 35.In the time of 1000,2000,3000 hours, device is tested with stock oil in the table 3 under the standard operation condition in the steady running of slag input oil, and test-results sees Table 6.

Table 6: test-results

Processing condition:
										Reaction pressure, MPa	15.7
Temperature of reaction, ℃	385
										Hydrogen-oil ratio, v/v	758
Volume space velocity, h -1	0.20
										Runtime, h	1000			2000			3000
Hydrogen consumption (to fresh feed) m%	1.60			1.58			1.57
										Test-results:
Reactor	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-
										The bed temperature rise, ℃	10	25	16	9	22	14	8	21	13
Desulfurization degree, %	46.0	28.5	16.0	45.5	27.5	17.2	45.1	26.7	18.1
										Denitrification percent, %	0.82	30.4	26.8	0.65	29.7	26.4	0.45	28.9	25.9
Take off carbon yield, %	33.5	14.0	18.4	32.9	13.6	18.1	32.6	13.3	18.0
										Take off (Ni+V) rate, %	77.4	2.52	7.30	76.5	2.31	7.51	75.4	2.13	7.86
Decreasing ratio refers to each anti-clean decreasing ratio that generates oil to corresponding impurity in the stock oil that device advances

Embodiment 4

On the testing apparatus that three reactor 3 liters are arranged, adopt catalyzer, standard test condition, the stock oil evaluation test identical with embodiment 1.Each anti-inert bed filling, anticatalyzer filling are instead loaded ZTS01, (ZTS01+ZTS02), ZTS02 from top to bottom with embodiment 1, two, and filling ratio (V) is 50: 4.5: 50, and wherein the ratio of transition layer ZTS01, ZTS02 is 50v%: 50v%; Three instead load ZTN01, (ZTN01+ZTN02), ZTN02 from top to bottom, and filling ratio (V) is 80: 4.5: 20, and wherein the ratio of transition layer ZTN01, ZTN02 is 80v%: 20v%; The filling ratio (V) of three reactors is 45: 20: 35.In the time of 1000,2000,3000 hours, device is tested with stock oil in the table 3 under the standard operation condition in the steady running of slag input oil, and test-results sees Table 5.

Table 7: test-results

Processing condition:
										Reaction pressure, MPa	15.7
Temperature of reaction, ℃	385
										Hydrogen-oil ratio, v/v	758
Volume space velocity, h -1	0.20
										Runtime, h	1000			2000			3000
Hydrogen consumption (to fresh feed) m%	1.61			1.58			1.58
										Test-results:
Reactor	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-	One is anti-	Two is anti-	Three is anti-
										The bed temperature rise, ℃	10	19	20	9	17	18	8	15	18
Desulfurization degree, %	46.0	27.4	16.9	45.5	26.4	18.1	45.1	25.7	19.1
										Denitrification percent, %	0.82	29.3	27.6	0.65	28.8	27.3	0.45	27.7	27.0
Take off carbon yield, %	33.5	13.0	19.3	32.9	12.6	19.1	32.6	12.2	18.9
										Take off (Ni+V) rate, %	77.4	2.51	7.52	76.5	2.16	7.69	75.4	1.78	7.80
Decreasing ratio refers to each anti-clean decreasing ratio that generates oil to corresponding impurity in the stock oil that device advances

Claims (10)

1. the grading method of a catalyst for hydrotreatment of residual oil: it is characterized in that desulfurization, denitrification reaction district respectively are divided into two or more beds, and between two beds, set up a mixed transition bed.

2. according to the described grading method of claim 1, it is characterized in that desulfurization, denitrification reaction district respectively are divided into two beds, be respectively the first desulfurization bed, the second desulfurization bed and the first denitrogenation bed and the second denitrogenation bed; And between the first desulfurization bed and the second desulfurization bed, set up a transition desulfurization bed, between the first denitrogenation bed and the second denitrogenation bed, set up a transition denitrogenation bed.

3. according to the described grading method of claim 2, it is characterized in that the content of active ingredient in the said first desulfurization bed catalyzer is: MoO ₃16.0-22.0m%, NiO4.0-7.0m%, P1.5-2.5m%; The second desulfurization bed catalyst activity component concentration is: MoO ₃12.0-18.0m%, NiO3.0-6.0m%, P1.5-2.5m%.

4. according to claim 2 or 3 described grading methods, it is characterized in that the content of active ingredient in the said first desulfurization bed catalyzer is: MoO ₃18.0-20.0m%, NiO4.5-5.5m%, P1.5-2.5m%; The second desulfurization bed catalyst activity component concentration is: MoO ₃14.0-18.0m%, NiO 3.5-4.5m%, P content are 1.5-2.5m%.

5. according to the described grading method of claim 2, it is characterized in that the said first denitrogenation bed activity of such catalysts component concentration is: MoO ₃20.0-26.0m%, NiO 8.0-10.0m%; The second denitrogenation bed catalyst activity component concentration is: MoO ₃16.0-22.0m%, NiO 6.0-8.0m%.

6. according to claim 2 or 3 described grading methods, it is characterized in that the said first denitrogenation bed activity of such catalysts component concentration is: MoO ₃22.0-24.0m%, NiO 8.5-9.5m%; The second denitrogenation bed catalyst activity component concentration is: MoO ₃18.0-20.0m%, NiO 6.5-7.5m%.

7. according to the described grading method of claim 2, the filling ratio that it is characterized in that the said first desulfurization bed and the second desulfurization bed catalyzer is 80v%/20v%-50v%/50v%, and the filling ratio of the first denitrogenation bed and the second denitrogenation bed catalyzer is 80v%/20v%-50v%/50v%.

8. according to the described grading method of claim 7, it is characterized in that the filling ratio of the said first desulfurization bed and the second desulfurization bed catalyzer is: 70v%/30v%-60v%/40v%; The filling ratio of the first denitrogenation bed and the second denitrogenation bed catalyzer is: 70v%/30v%-60v%/40v%.

9. according to the described grading method of claim 2, it is characterized in that said transition desulfurization bed accounts for the 2-5v% of whole desulfurization catalyst bed, the catalyzer that wherein contains the first desulfurization bed and the second desulfurization bed, the blending ratio of two kinds of catalyzer are 50v%/50v%-20v%/80v%.

10. according to the described grading method of claim 2, it is characterized in that said transition denitrogenation bed accounts for the 2-5v% of whole denitrogenation bed, the catalyzer that wherein contains the first denitrogenation bed and the second denitrogenation bed, the blending ratio of two kinds of catalyzer are 50v%/50v%-20v%/80v%.

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