Preparation method of hydrotreating catalyst
阅读说明：本技术 一种加氢处理催化剂的制备方法 (Preparation method of hydrotreating catalyst ) 是由 蒋淑娇 袁胜华 张�成 杨刚 丁思佳 关月明 韩易潼 李安琪 于 2019-10-29 设计创作，主要内容包括：本发明公开了一种加氢处理催化剂的制备方法。该方法包括：配制含活性金属的浸渍液,所述含活性金属的浸渍液中含有有机助剂I和有机助剂II,其中有机助剂I为氨三乙酸、乙二胺四乙酸、环己二胺四乙酸或二乙基三胺五乙酸中的一种或几种,有机助剂II为脂肪酸山梨坦、聚山梨酯或豆磷脂中的一种或几种；将载体浸渍上述含活性金属的浸渍液,然后干燥和焙烧,得到加氢处理催化剂。该方法制备的催化剂用作渣油加氢处理催化剂时,具有良好的活性和稳定性。(The invention discloses a preparation method of a hydrotreating catalyst. The method comprises the following steps: preparing an active metal-containing impregnation solution, wherein the active metal-containing impregnation solution contains an organic auxiliary agent I and an organic auxiliary agent II, the organic auxiliary agent I is one or more of nitrilotriacetic acid, ethylene diamine tetraacetic acid, cyclohexanediamine tetraacetic acid or diethyltriamine pentaacetic acid, and the organic auxiliary agent II is one or more of sorbitan fatty acid, polysorbate or soybean lecithin; and (3) impregnating the carrier into the impregnation liquid containing the active metal, and then drying and roasting to obtain the hydrotreating catalyst. The catalyst prepared by the method has good activity and stability when being used as a residual oil hydrotreating catalyst.)
1. A method of preparing a hydroprocessing catalyst, comprising:
(1) preparing an active metal-containing impregnation solution, wherein the active metal-containing impregnation solution contains an organic auxiliary agent I and an organic auxiliary agent II, the organic auxiliary agent I is one or more of nitrilotriacetic acid, ethylene diamine tetraacetic acid, cyclohexanediamine tetraacetic acid or diethyltriamine pentaacetic acid, and the organic auxiliary agent II is one or more of sorbitan fatty acid, polysorbate or soybean lecithin;
(2) and (2) impregnating the carrier into the impregnation liquid containing the active metal obtained in the step (1), and then drying and roasting to obtain the hydrotreating catalyst.
2. The method of claim 1, wherein: in the organic auxiliary agent II, the sorbitan fatty acid is at least one selected from sorbitan monostearate, sorbitan trioleate and lauryl sorbitan, and the polysorbate is at least one selected from polysorbate-80, polysorbate-60 and polysorbate-20.
3. The method of claim 1, wherein: the active metal is selected from group VIB and group VIII metals, the group VIB metal preferably being W and/or Mo, and the group VIII metal preferably being Ni and/or Co.
4. The method of claim 1, wherein: in the step (1), the concentration of the organic assistant I in the impregnation liquid containing the active metal is 0.1-1.5mol/L, preferably 0.2-0.6mol/L, and the concentration of the organic assistant II in the impregnation liquid containing the active metal is 1.0-20.0g/L, preferably 2.0-5.0 g/L.
5. The method of claim 1, 3 or 4, wherein: in the step (1), the molar concentration of the group VIB metal in the impregnation liquid containing the active metal is 0.2-2.0mol/L, preferably 0.6-1.0mol/L, and the molar concentration of the group VIII metal is 0.1-2.0mol/L, preferably 0.3-0.6 mol/L.
6. The method according to claim 1 or 5, characterized in that: in the step (1), the impregnation liquid containing the active metal also contains phosphorus, and the molar concentration of the phosphorus is 0.1-2.0mol/L, preferably 0.2-0.8 mol/L.
7. The method of claim 1, wherein: in the step (1), the pH value of the impregnation liquid containing the active metal is controlled to be less than 4.0, preferably 1.0-3.0.
8. The method of claim 1, wherein: in the step (2), the carrier is an alumina-based carrier, and the properties are as follows: the specific surface area is 120-300m2Per g, preferably 160-280m2Per g, a pore volume of from 0.5 to 1.5mL/g, preferably from 0.8 to 1.0mL/g, and an average pore diameter of from 20 to 300nm, preferably from 50 to 150 nm.
9. The method of claim 1, wherein: the impregnation in the step (2) is equal-volume co-impregnation.
10. The method of claim 1, wherein: the drying conditions in the step (2) are as follows: the drying temperature is 80-140 ℃, preferably 90-130 ℃, and the drying time is 6.0-72.0h, preferably 12.0-24.0 h; the roasting conditions are as follows: the roasting temperature is 400-550 ℃, preferably 450-500 ℃, and the roasting time is 2.0-8.0h, preferably 3.0-4.0 h.
11. The method according to claim 1 or 10, characterized in that: after the impregnation before the drying step, a curing step is carried out, and standing is adopted for 1-20 hours.
12. A hydroprocessing catalyst characterized by: prepared by the process of any one of claims 1 to 11.
13. The catalyst of claim 12, wherein: the group VIB metal content, calculated as metal oxide, is from 5% to 24%, preferably from 8% to 15%, and the group VIII metal content, calculated as metal oxide, is from 1% to 8%, preferably from 2% to 5%, all by weight of the catalyst.
Technical Field
The invention relates to a preparation method of a hydrogenation catalyst, in particular to a preparation method of a residual oil hydrotreating catalyst.
Background
With the heavy and inferior crude oil and the increasing demand of high-quality and light fuel oil in the market, the inferior heavy oil processing technology has become the key research direction of various large petroleum companies and petroleum research institutes. Among them, the hydrotreating technology is one of the most effective technical schemes for improving the quality of inferior heavy oil and providing high-quality raw oil for downstream devices, and is currently receiving wide attention.
Because impurities such as metals in residual oil exist in colloid and asphaltene, which have large molecules and complex structures and are difficult to diffuse in the internal pore channels of the catalyst, the hydrotreating catalyst is required to have good pore channel structures and active metal dispersibility to promote the diffusion and reaction of macromolecular reaction substances in catalyst particles, thereby obtaining higher impurity removal activity and stability.
The hydrotreating catalyst which is most widely applied at present is usually a supported catalyst, the carrier of the catalyst is generally an alumina-based carrier, and some conventional additives such as phosphorus, boron, fluorine, titanium, zirconium, silicon and the like can be added for modification. In the preparation process of the carrier, a pore-expanding agent is usually added to increase the pore diameter of the carrier and improve the diffusion performance of the catalyst. Hydrotreating catalysts typically have group VIB and group VIII metals as the active metal components. The most common method for preparing the hydrotreating catalyst is impregnation, which is generally to prepare an impregnation solution containing an active metal, and then immerse the carrier in the impregnation solution to carry out impregnation and loading.
CN101927196A discloses a preparation method of a hydrotreating catalyst, which comprises the following steps: and gradually reducing the concentration of the metal component in the solution or sequentially spraying and soaking different solutions with the concentration from high to low in the process of spraying and soaking the active metal solution to prepare the hydrotreating catalyst with the active metal component solution in gradient reduction distribution. The spray-dipping method is uncontrollable, so that the distribution uniformity of the metal solution in each carrier particle is difficult to ensure, thereby influencing the catalytic performance of the catalyst, and the preparation process of the method is complex.
In the prior art, how to well match the pore structure of a residual oil hydrotreating catalyst with metal dispersion has good diffusion performance, and can improve reaction activity and impurity-containing capacity, which is a great problem to be solved in the field.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a preparation method of a hydrotreating catalyst. The catalyst prepared by the method has good activity and stability when being used as a residual oil hydrotreating catalyst.
The invention provides a preparation method of a hydrotreating catalyst, which comprises the following steps:
(1) preparing an active metal-containing impregnation solution, wherein the active metal-containing impregnation solution contains an organic assistant I and an organic assistant II, the organic assistant I is one or more of nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), cyclohexanediaminetetraacetic acid (CyDTA) or diethyltriaminepentaacetic acid (DTPA), and the organic assistant II is one or more of sorbitan fatty acid, polysorbate or soybean lecithin;
(2) and (2) impregnating the carrier into the impregnation liquid containing the active metal obtained in the step (1), and then drying and roasting to obtain the hydrotreating catalyst.
In the invention, the organic auxiliary agent II is one or more of sorbitan fatty acid, polysorbate or soybean phospholipid. Wherein the sorbitan fatty acid is at least one selected from sorbitan monostearate, sorbitan trioleate and lauryl sorbitan, and the polysorbate is at least one selected from polysorbate-80, polysorbate-60 and polysorbate-20.
In the present invention, the active metal is selected from group VIB and group VIII metals, the group VIB metal is preferably W and/or Mo, and the group VIII metal is preferably Ni and/or Co.
In the step (1) of the invention, in the impregnation liquid containing the active metal, the concentration of the organic auxiliary agent I is 0.1-1.5mol/L, preferably 0.2-0.6mol/L, and the concentration of the organic auxiliary agent II is 1.0-20.0g/L, preferably 2.0-5.0 g/L.
In the step (1) of the invention, in the impregnation liquid containing the active metal, the molar concentration of the group VIB metal is 0.2-2.0mol/L, preferably 0.6-1.0mol/L, and the molar concentration of the group VIII metal is 0.1-2.0mol/L, preferably 0.3-0.6 mol/L. The group VIB metal and the group VIII metal may be introduced by using conventionally available substances, for example, the W source may be ammonium metatungstate, the Mo source may be at least one of molybdenum oxide, ammonium molybdate and ammonium paramolybdate, the Ni source may be at least one of basic nickel carbonate, nickel carbonate and nickel nitrate, and the Co source may be at least one of basic cobalt carbonate, cobalt carbonate and cobalt nitrate.
In the step (1) of the present invention, the impregnation solution containing active metal may further contain phosphorus, and the molar concentration of phosphorus is 0.1 to 2.0mol/L, preferably 0.2 to 0.8 mol/L. The phosphorus source may be phosphoric acid.
In step (1) of the present invention, the pH of the impregnation liquid containing an active metal is controlled to 4.0 or less, preferably 1.0 to 3.0.
In the step (2), the carrier is an alumina-based carrier, and the properties are as follows: the specific surface area is 120-300m2Per g, preferably 160-280m2Per g, a pore volume of from 0.5 to 1.5mL/g, preferably from 0.8 to 1.0mL/g, and an average pore diameter of from 20 to 300nm, preferably from 50 to 150 nm. The alumina-based carrier means that alumina is taken as a main component, and conventional auxiliary components, such as at least one of boron, silicon, titanium, zirconium, fluorine and the like, can be contained.
In the step (2), the alumina-based carrier can be prepared by taking dry glue powder of aluminum hydroxide as a raw material, introducing a pore-expanding agent in the forming process, and drying and roasting the pore-expanding agent. The aluminum hydroxide dry glue powder can be macroporous aluminum oxide dry glue powder, and can be commercially available or prepared by any one of the prior arts. The pore-expanding agent comprises one or more of ammonium bicarbonate, ammonium dihydrogen phosphate, urea and ammonium nitrate, preferably ammonium bicarbonate. The introduction mode of the pore-expanding agent can be physical mixing, or the pore-expanding agent can be dissolved in water and then mixed with dry rubber powder. The amount of the pore-expanding agent (by mass fraction) is 10-50%, preferably 25-45% of the mass of the alumina dry glue powder. Peptizing acid and extrusion aid can be added in the forming process, the cosolvent comprises one or more of nitric acid, acetic acid and oxalic acid, and the dosage (by mass) is 1-5% of the dry alumina gel powder. The extrusion aid comprises one or more of sesbania powder and starch, and the amount (by mass) of the extrusion aid is 2-6% of that of the alumina dry glue powder.
In the method of the present invention, the impregnation in step (2) may be an equal-volume impregnation, an excess impregnation, a stepwise impregnation, a co-impregnation, and preferably an equal-volume co-impregnation.
In the method of the present invention, the drying conditions in step (2) are as follows: the drying temperature is 80-140 ℃, preferably 90-130 ℃, and the drying time is 6.0-72.0h, preferably 12.0-24.0 h; the roasting conditions are as follows: the roasting temperature is 400-550 ℃, preferably 450-500 ℃, and the roasting time is 2.0-8.0h, preferably 3.0-4.0 h. Preferably, there is a curing step, typically by standing for a period of time, for example 1 to 20 hours, after impregnation prior to the drying step.
In another aspect, the present invention provides a hydroprocessing catalyst prepared by the above process, having a group VIB metal (calculated as metal oxide) content of from 5% to 24%, preferably from 8% to 15%, and a group VIII metal (calculated as metal oxide) content of from 1% to 8%, preferably from 2% to 5%, by weight of the final catalyst.
In the catalyst of the invention, the content of phosphorus in the hydrotreating catalyst is 0.1-6%.
In the catalyst of the invention, the properties are as follows: specific surface area of 100-230m2/g, preferably 110-170m2The pore volume is 0.2 to 0.7mL/g, preferably 0.3 to 0.65 mL/g.
The method of the invention has the following advantages:
in the method, the organic assistant I and the organic assistant II are added into the impregnation liquid containing the active metal, so that the active metal can be selectively and uniformly diffused under the synergistic action of the two assistants, the active metal is mainly and uniformly distributed in relatively larger pore passages, the active metal in small pores is relatively less distributed, and the effect is more prominent when the impregnation liquid is particularly matched with a macroporous alumina-based carrier. Compared with the conventional impregnation method, the hydrotreating catalyst prepared by the method can greatly improve the hydrogenation activity under the condition of using the same amount of active metal, can also improve the hydrogenation activity and the capability of the catalyst for containing impurities such as metal and the like under the condition of reducing the use amount of the active metal, and prolongs the operation period.
Detailed Description
The following examples and comparative examples are given to further illustrate the action and effect of the method of the present invention, but the following examples are not intended to limit the method of the present invention.
Example 1
This example describes the preparation of a hydroprocessing catalyst using ammonium bicarbonate as a pore-expanding agent and nitrilotriacetic acid as organic adjuvant I and sorbitan monostearate as organic adjuvant II.
60.0 g of ammonium bicarbonate is weighed and dissolved in 220.0 g of water, and is mixed with 200.0 g of aluminum hydroxide dry glue powder, and 20.0g of nitric acid with the mass fraction of 30 percent, 2.0g of citric acid, 2.0g of sesbania powder and 2.0g of starch are added. Rolling for 15.0min, extruding with 1.7mm diameter clover orifice plate, drying at 120 deg.C for 4.0 hr, and roasting at 500 deg.C for 4.0 hr to obtain the carrier. This vector is designated as Z-1. The properties of Z-1 are as follows: specific surface area of 265m2The volume of pores is 0.92mL/g, and the average pore diameter is 143 nm.
100 mL of the composition was prepared from ammonium molybdate, nickel nitrate and phosphoric acid, and contained Mo (0.09 mol), Ni (0.04mol) and P (0.03 mol), which were denoted as Q-0.
The 200 mLQ-0 solution was taken, 20.0g of nitrilotriacetic acid and 0.6 g of sorbitan monostearate were added, mixed well and concentrated to 200mL at 80 ℃ to give solution Q-1, at which time the pH of the solution was 1.6.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, immersing Z-1 in the solution Q-1, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst C-1.
Example 2
This example describes the preparation of a hydroprocessing catalyst using ammonium bicarbonate as a pore-expanding agent and ethylenediaminetetraacetic acid as organic adjuvant I and polysorbate-80 as organic adjuvant II.
The macroporous alumina support Z-1 and solution Q-0 were prepared as in example 1.
Adding 24.0g of ethylenediamine tetraacetic acid and 0.8g of polysorbate-80 into 200 mLQ-0 solution, mixing well, and concentrating to 200mL at 80 ℃ to obtain solution Q-2, wherein the pH value of the solution is 2.3.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, impregnating Z-1 with the solution Q-2, standing the impregnated catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst C-2.
Example 3
This example describes the preparation of a hydroprocessing catalyst using ammonium bicarbonate as a pore-expanding agent and cyclohexanediaminetetraacetic acid as organic adjuvant I and soy lecithin as organic adjuvant II.
The macroporous alumina support Z-1 and solution Q-0 were prepared as in example 1.
200mL of Q-0 solution was taken, 22.0 g of cyclohexanediaminetetraacetic acid and 0.5 g of soy lecithin were added, mixed well, and concentrated to 200mL at 80 ℃ to give solution Q-3, at which time the pH of the solution was 2.1.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, impregnating Z-1 with the solution Q-3, standing the impregnated catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst C-3.
Example 4
This example describes the preparation of a hydroprocessing catalyst using ammonium bicarbonate as a pore-expanding agent and diethyltriaminepentaacetic acid as organic adjuvant I and polysorbate-60 as organic adjuvant II.
The macroporous alumina support Z-1 and solution Q-0 were prepared as in example 1.
Adding 30.0g of diethyltriaminepentaacetic acid and 0.8g of polysorbate-60 into 200 mLQ-0 solution, mixing well, and concentrating to 200mL at 80 ℃ to obtain solution Q-4, wherein the pH value of the solution is 1.8.
Weighing 100.0gZ-1, adopting an isovolumetric co-immersion method, impregnating Z-1 with the solution Q-4, standing the impregnated catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst C-4.
Comparative example 1
This comparative example describes the preparation of a support using dry alumina gel powder without treatment with a pore-expanding agent, and a hydroprocessing catalyst prepared using an impregnation solution without organic auxiliary I and organic auxiliary II.
200.0 g of aluminum hydroxide dry glue powder is weighed, and 20.0g of a mixture of 30 mass percent nitric acid, 2.0g of citric acid, 2.0g of sesbania powder and 2.0g of starch are added. Rolling for 15.0min, and extruding with 1.7mm diameter clover orifice plate. Drying at 120 ℃ for 4.0h, and then roasting at 500 ℃ for 4.0 h. This vector is designated as Z-2.
Solution Q-0 was prepared as in example 1.
Weighing 100.0g Z-2, adopting an isovolumetric co-immersion method, immersing Z-2 in the solution Q-0, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst D-1.
Comparative example 2
This comparative example describes the preparation of a macroporous alumina support from dry alumina powder treated with ammonium bicarbonate as a pore-expanding agent, and the preparation of a hydroprocessing catalyst using an impregnation fluid without organic auxiliary agent I and organic auxiliary agent II.
The macroporous alumina support Z-1 and solution Q-0 were prepared as in example 1.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, immersing Z-1 in the solution Q-0, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst D-2.
Comparative example 3
This comparative example describes the preparation of a macroporous alumina support using ammonium bicarbonate as a pore-expanding agent and a hydroprocessing catalyst using an impregnation solution without organic auxiliary agent II.
The alumina support Z-1 was prepared as in example 1.
Solution Q-0 was prepared as in example 1.
Adding 24.0g of ethylenediamine tetraacetic acid into the 200 mLQ-0 solution, fully mixing, and concentrating to 200mL at 80 ℃ to obtain a solution DQ-1.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, immersing Z-1 in the solution DQ-1, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst D-3.
Comparative example 4
This comparative example describes the preparation of a macroporous alumina support from dry alumina powder treated with ammonium bicarbonate as a pore-expanding agent, and the preparation of a hydroprocessing catalyst using an impregnation solution without organic auxiliary agent I.
The macroporous alumina support Z-1 and solution Q-0 were prepared as in example 1.
Adding 0.8g of polysorbate-80 into the 200 mLQ-0 solution, mixing well, and concentrating to 200mL at 80 ℃ to obtain solution DQ-2.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, immersing Z-1 in the solution DQ-2, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst D-4.
Comparative example 5
This comparative example describes the preparation of a macroporous alumina support from dry alumina powder treated with ammonium bicarbonate as a pore-expanding agent, and the preparation of a hydroprocessing catalyst using an impregnation fluid without organic auxiliary agent I and organic auxiliary agent II. And the loading of active metals Mo and Ni is larger.
100 mL of the composition was prepared from ammonium molybdate, nickel nitrate and phosphoric acid, and the composition contained Mo (0.13 mol), Ni (0.06mol) and P (0.05 mol), which was designated as DQ-5.
Weighing 100.0g Z-1, adopting an isovolumetric co-immersion method, immersing Z-1 in the solution DQ-5, standing the immersed catalyst at room temperature for 10.0h, drying at 120 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain the catalyst D-5.
The compositions and properties of the catalysts of the examples of the invention and the comparative examples are shown in Table 1. The properties of the feed oil are shown in Table 2. The conditions for evaluating the activity of the catalysts in examples and comparative examples are shown in Table 3, the results of evaluating the activity of the catalysts in examples and comparative examples (200 hours of operation) are shown in Table 4, and the results of evaluating the stability are shown in Table 5.
TABLE 1 compositions and Properties of catalysts in examples and comparative examples
Catalyst and process for preparing same
C-1
C-2
C-3
C-4
D-1
D-2
D-3
D-4
D-5
Composition of
MoO3，wt%
10.9
11.0
10.8
11.3
10.5
10.7
11.2
10.8
14.8
NiO，wt%
2.51
2.60
2.48
2.49
2.50
2.55
2.62
2.59
3.2
P2O5，wt%
1.75
1.76
1.75
1.78
1.82
1.76
1.73
1.79
2.80
Properties of
Specific surface area, m2·g-1
210
226
213
219
264
248
219
222
208
Total pore volume, mL. g-1
0.76
0.75
0.79
0.78
0.54
0.50
0.83
0.85
0.73
Average pore diameter, nm
125
121
126
130
16.3
14.7
130
119
115
TABLE 2 Properties of the feed oils
Properties of crude oil
S/wt%
3.63
N/wt%
0.68
Ni/μg·g-1
23.2
V/μg·g-1
66.9
Carbon residue/wt%
17.8
Table 3 conditions for evaluating the activity of catalysts in examples and comparative examples
Reaction conditions
Temperature/. degree.C
380
pressure/MPa
16.0
Liquid hourly space velocity/h-1
0.8
Volume ratio of hydrogen to oil
900
Table 4 evaluation results of catalyst activity in examples and comparative examples
Catalyst and process for preparing same
C-1
C-2
C-3
C-4
D-1
D-2
D-3
D-4
Relative desulfurization activity of%
179
186
222
180
100
126
146
135
Relative denitrification activity,%
175
183
188
235
100
132
152
142
Relative carbon residue removal activity%
179
216
190
183
100
137
155
140
Relative nickel-removing activity,%
160
143
145
139
100
128
137
134
Relative to the vanadium-removing activity,%
176
141
146
142
100
137
132
136
Table 5 evaluation results of catalyst activity and stability in examples and comparative examples
Catalyst numbering
Running time, h
C-2
D-2
D-3
D-4
D-5
Relative desulfurization activity of%
200
186
126
146
135
128
2000
172
105
122
116
106
Relative denitrification activity,%
200
183
132
152
142
135
2000
170
103
119
108
101
Relative carbon residue removal activity%
200
216
137
155
140
137
2000
189
101
121
109
106
Relative nickel-removing activity,%
200
143
128
137
134
132
2000
140
106
112
127
110
Relative to the vanadium-removing activity,%
200
141
137
132
136
139
2000
138
109
111
122
108
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