CN101279253A - Catalyst for eliminating chlorinated aromatic hydrocarbons by low-temperature catalytic combustion - Google Patents
Catalyst for eliminating chlorinated aromatic hydrocarbons by low-temperature catalytic combustion Download PDFInfo
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- CN101279253A CN101279253A CNA2008100372155A CN200810037215A CN101279253A CN 101279253 A CN101279253 A CN 101279253A CN A2008100372155 A CNA2008100372155 A CN A2008100372155A CN 200810037215 A CN200810037215 A CN 200810037215A CN 101279253 A CN101279253 A CN 101279253A
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Abstract
The invention discloses a catalyst for catalyzing, burning and removing volatile chloro-aromatics at low temperature, which is mainly composed of variable-valence transition metal element M such as Cu, Fe, V, Mn, Mo, and W and one or more rare earth oxides. The oxide content of variable-valence transition metal is 50-90wt percent, and the oxide content of the rare earth oxide is 10-50 percent. The catalyst of the invention is characterized by high catalytic activity, no byproduct, no secondary pollution, high anti-chlorine poisoning capability and long service life, which is especially suitable for completely catalyzing, burning and removing organic compound containing halogen at low temperature and especially the contamination of the volatile chloro-aromatics.
Description
Technical field
The invention belongs to the catalytic combustion environmental protection technical field; specially refer to a kind of rare earth based oxide catalyst that is used for the elimination of easy-to-volatile chloroarene low-temperature catalytic burning and preparation method thereof, and a kind of method that complete catalytic combustion is eliminated environment easy-to-volatile chloroarene pollutant that is used for is provided.
Background technology
The chlorine-containing volatile hydro carbons not only can cause serious harm to human beings'health, also can cause influence lasting, accumulation property to biosystem, and can destroy atmospheric ozone layer.It all is chloride organic compound that 12 persistent organic pollutions of classifying the first place as are arranged in the united nations environment project international treaties.The chlorine-containing volatile hydro carbons divides the aromatic hydrocarbon chloride, as chlorobenzene, dichloro-benzenes, and non-aromatic face cream fat hydro carbons chloride, as dichloroethanes, trichloro-ethylene, tetrachloro-ethylene, chloromethanes and methane polychloride etc., the former results from waft white, the heat treatment of chlorine-containing compound and the recovery of metal of the wood pulp of chloro oxidant; The latter mainly results from chlorine industry oxygen chlorine legal system and is equipped with industries such as vinyl chloride process, process hides, washing, pharmacy.Because the muriatic process of above-mentioned generation all relates to the industry of present stage national economy, the discharging of a large amount of chlorine-containing compounds is inevitable.Therefore, the pollution that is caused from source elimination chlorine-containing volatile hydro carbons does not also possess possibility at present.And the pollution that the method elimination chlorine-containing volatile hydro carbons of taking post processing is brought becomes unique feasible approaches and methods.
In recent years, the comprehensive regulation to volatile organic compound (VOCs) had received concern more and more widely.Methods such as flame combustion, catalytic combustion and absorption are to eliminate the common method of these pollutants.But flame combustion need carry out under higher temperature (1000 ℃), and energy consumption is big; And this method is also causing more highly toxic bioxin (Dioxins) pollutant aspect the chloride hydro carbons of processing, as many chlorodiphenyls and bioxin (PCDD) and polychlorinated dibenzo (PCDF).Absorption method as one of organic pollution common method is unsatisfactory for the treatment effect of low concentration pollutant, and its adsorption efficiency is extremely low.For the elimination of the chloride aromatic hydrocarbon of effumability, the method for multiple novelty has been proposed recently in succession, as biological processes, photocatalytic degradation, hydrogenation-dechlorination etc.But these methods are not to have defective technically, are exactly that disposal cost is high, all are in the laboratory research state mostly, are difficult for realizing industrialization, industrialization.
Advantages such as the pollution that catalytic combustion is eliminated organic compound is a kind of energy-conservation, economic, effective processing method, compares with flame combustion, and it has, and ignition temperature is low, the time of staying short, required reactor is little, secondary pollution is few.Therefore, catalytic combustion is obtaining using widely aspect the elimination volatile organic compound.
Chlorination aromatic hydrocarbon such as chlorobenzene, dichlorobenzene, dioxin, its catalytic combustion is mainly used in the exhaust-gas treatment of incinerator, and the research work of this direction and the exploitation of technology concentrate on Japan.Representational patent has Jpn.Kokai Tokkyo Koho JP 2001286729 A2, Jpn.Kokai Tokkyo Koho JP2001286730 A2, Jpn.Kokai Tokkyo Koho JP 2001286734 A2, Jpn.Kokai TokkyoKoho JP 10085559 A2 etc.Use fuel gas and air to burn.The main catalyst activity component of using is transition metal and noble metal, and carrier is SiO
2, Al
2O
3, TiO
2, ZrO
2Though precious metal catalyst is active higher, is easy to fluorine poisoning; The anti-poisoning capability of non-precious metal catalyst is stronger, but selectivity is lower, often has polystream to produce.
Part chlorination aromatic hydrocarbon catalytic combustion granted patent has:
[1]Nawama，Junichi；Moriya，Yoshifumi；Suzuki，Tadashi；Kuchino，Kunikazu，Jpn.Kokai Tokkyo Koho JP 2002219364 A2
[2]Kiyono，Kenichi；Uchida，Masaaki；Adachi，Kentaro；Nishii，Kazuhiro，Jpn.Kokai Tokkyo Koho JP 2001286729 A2
[3]Kiyono，Kenichi；Uchida，Masaaki；Adachi，Kentaro；Nishii，Kazuhiro，Jpn.Kokai Tokkyo Koho JP 2001286730 A2
[4]Kajikawa，Osamu；Wang，Hsiang Sheng；Kawase，Noboru；Maeda，Takeshi，Jpn.Kokai Tokkyo Koho JP 2001009284 A2.
[5]Kiyono，Kenichi；Uchida，Masaaki；Adachi，Kentaro；Nishii，Kazuhiro，Jpn.Kokai Tokkyo Koho JP 2001286734 A2
[6]Moriya，Yoshifumi；Nawama，Junichi；Tokumitsu，Shuzo，Jpn.Kokai TokkyoKoho JP 2001327869 A2
These patent works mainly are to be active component with the transition metal, and catalytic combustion purifies De bioxin in the incinerator.
All there is shortcoming more or less in the catalyst that above-mentioned chlorine-containing volatile hydro carbons catalytic combustion elimination is adopted, low as catalytic combustion activity, have the polychlorocarbon class to produce, easily cause secondary pollution in the catalyticing combustion process, the catalyst activity component runs off easily, catalyst life short.
Summary of the invention
The objective of the invention is to disclose a kind of rare earth based oxide catalyst that is used for the elimination of easy-to-volatile chloroarene low-temperature catalytic burning and preparation method thereof, its catalytic activity height, no coupling product generate, do not cause secondary pollution, anti-fluorine poisoning ability is strong, catalyst life is long, be specially adapted to complete catalytic combustion and eliminate halogen-containing organic compound, especially effumability chloro-hydrocarbons pollutant.
The invention provides a kind of catalyst that the easy-to-volatile chloroarene low-temperature catalytic burning is eliminated that is used for, this catalyst mainly is made up of one or several of appraise at the current rate transition metal M such as Cu, Fe, V, Mn, Mo, Co, W and rare earth oxide.The transition metal that appraises at the current rate is 50～90wt.% (oxide content), is preferably 70～90wt.%; Rare earth oxide is 10～50wt.%, is preferably 10～20wt.%.The transition metal that preferably appraises at the current rate is Mn, Cu, Fe; Preferred rare earth element is Ce and La.
The multicomponent catalyst that the transition metal oxide that appraises at the current rate adds rare earth element adopts sol-gal process to make, and the presoma of transition metal oxide is selected from nitrate, oxalates, acetate, carbonate; The rare earth element presoma is selected from the nitrate of rare earth.
The invention provides a kind of method that complete catalytic combustion is eliminated environment volatile chloro fat hydrocarbon pollutant that is used for.The invention provides following technology path:
In the presence of catalyst, adopt and bring reactor into as the air of oxidant, make the completing combustion under the effect of catalyst of chlorine-containing volatile aromatic hydrocarbon, chlorine-containing volatile aromatic hydrocarbon is transformed into carbon dioxide, hydrogen chloride and chlorine.Completing combustion tail gas can adopt dilute alkaline soln to absorb back emptying such as (hydrogen chloride/chlorine sour gas).
Reaction pressure is 0.1～1Mpa, preferred 0.1～0.5Mpa, especially 0.1Mpa, and near normal pressure, temperature is 100～400 ℃, is preferably 150～450 ℃, especially 350 ℃.
Catalyst consumption, must be enough to make chlorine-containing volatile aromatic hydrocarbon existing under the situation at humid air, change into carbon dioxide and hydrogen chloride, generally speaking, the concentration of chlorine-containing volatile aromatic hydrocarbon is 0.05～5vol% in the waste gas of chlorine-containing volatile aromatic hydrocarbon, and every gram catalyst treatment exhausted air quantity is 10～30L per hour.
Catalyst provided by the invention has characteristics such as preparation technology is simple, cheap, catalytic activity is high, anti-fluorine poisoning ability is strong, the life-span is long; Technology path is convenient and practical, and the catalytic combustion that can be widely used in the chlorine-containing volatile arene pollutant in papermaking, pharmacy, process hides, washing and the chemical industry waste gas is eliminated.
The specific embodiment
Embodiment 1
With commercially available 41g cerous nitrate (Ce (NO
3)
3) 6H
2O, 41g lanthanum nitrate La (NO
3)
36H
2O is put into 409g Mn (NO
3)
2In the 50wt% aqueous solution, after the room temperature dissolving, add the 200g citric acid again, and make its dissolving, add deionized water and make the volume of solution reach 700ml.This solution places 80 ℃ constant temperature water bath to stir 6～7h; Put into 110 ℃ the dry 12h of drying box then, move in the roaster, temperature programming in air atmosphere, 4.2 ℃ of per minutes are raised to 550 ℃, and insulation 5h can obtain 88%Mn
2O
3-6%CeO
2-6%La
2O
3Catalyst.Compressing tablet is pulverized 20-40 purpose particle, and is stand-by.
With implement 1 method make 80%Fe
2O
3-10%CeO
2-10%La
2O
3Catalyst is embodiment 2.
With implement 1 method make 80%Mn
2O
3-10%CeO
2-10%La
2O
3Catalyst is embodiment 3.
To implement 1 prepared 88%Mn
2O
3-6%CeO
2-6%La
2O
3Catalyst is embodiment 4 at 650 ℃ of roasting 5h.
To implement 1 prepared 88%Mn
2O
3-6%CeO
2-6%La
2O
3Catalyst is embodiment 5 at 750 ℃ of roasting 5h.
Embodiment 6
With commercially available 82g cerium (Ce (NO
3)
3) 6H
2O is put into 409g Mn (NO
3)
2In the 50wt% aqueous solution, after the room temperature dissolving, add the 200g citric acid again, and make its dissolving, add deionized water and make the volume of solution reach 700ml.This solution places 80 ℃ constant temperature water bath to stir 6～7h; Put into 110 ℃ the dry 12h of drying box then, move in the roaster, temperature programming in air atmosphere, 4.2 ℃ of per minutes are raised to 550 ℃, and insulation 5h can obtain 88%Mn
2O
3-12%CeO
2Catalyst.
Make 80%NiO-20%CeO with the method for implementing 6
2Catalyst is embodiment 7.
Make 80%Co with the method for implementing 6
2O
3-20%CeO
2Catalyst is embodiment 8.
Embodiment 9
The catalyst activity evaluation is carried out at fixed bed reactors.The chlorobenzene combustion activity test of all catalyst is all carried out in U-shaped quartzy little anti-(internal diameter 6mm), and catalyst consumption is 200mg, and temperature adopts K type thermocouple to control automatically.Chlorobenzene adopts 100 serial KDS120 type micro-injection pumps injections of U.S. Stoelting company to enter vaporizer, then with enter reactor after air mixes and burn.Total flow adopts mass flowmenter control, and the concentration of chlorobenzene is controlled at 0.1vol%, and the amount that every gram catalyst is per hour handled waste gas is 15L, is 120m/h through the gas line speed of reactor.Reaction pressure is 0.1Mpa, and the conversion ratio of chlorobenzene and the relation of reaction temperature see Table 1, T in the table
10%, T
50%, T
98%Be respectively conversion ratio and reach 10%, 50%, 98% o'clock required reaction temperature.The key reaction product is the chlorine of carbon dioxide, hydrogen chloride and trace.
Chlorobenzene catalytic combustion properties on table 1 different catalysts
| Catalyst | T 10％(℃) | T 50％(℃) | T 98％(℃) |
| Embodiment 1 | 98 | 181 | 252 |
| Embodiment 2 | 185 | 261 | 449 |
| Embodiment 3 | 81 | 179 | 263 |
| Embodiment 4 | 86 | 185 | 260 |
| Embodiment 5 | 203 | 290 | 415 |
| Embodiment 6 | 79 | 174 | 255 |
| Embodiment 7 | 156 | 261 | 513 |
| Embodiment 8 | 185 | 286 | 514 |
Embodiment 10
The concentration of chloride aromatic hydrocarbon organic compound is controlled at 1～3vol.%, all the other are air, the amount that every gram catalyst is per hour handled waste gas is 10L, on embodiment 6 catalyst, the catalytic combustion properties of dissimilar chlorine-containing volatile arenes (CVOCs) is investigated, be the results are shown in Table 2.
The catalytic combustion result of the different chlorine-containing volatile chlorinated hydrocarbons of table 2
| Chlorinated aromatic hydrocarbons | T 10％(℃) | T 50％(℃) | T 98％(℃) |
| Dichloro-benzenes | 131 | 220 | 272 |
| Trichloro-benzenes | 135 | 233 | 282 |
| Tetrachlorobenzene | 148 | 248 | 300 |
The result shows, 88%Mn
2O
3-12%CeO
2Catalyst all has good catalytic combustion properties to dissimilar chlorine-containing volatile arenes.
Embodiment 11
Change the concentration of chlorobenzene, water in air branch concentration is controlled at 0.45～1vol.%, the amount that every gram catalyst is per hour handled waste gas is 20L, and reaction pressure is at 0.3～0.5Mpa, at 88%Mn
2O
3-12%CeO
2Investigated of the influence of variable concentrations chlorobenzene on the catalyst, the results are shown in Table 3 catalytic combustion properties.
Table 3 variable concentrations chlorobenzene is to 88%Mn
2O
3-12%CeO
2The influence of catalyst combustibility
The result shows, 88%Mn
2O
3-12%CeO
2Catalyst has good catalytic combustion properties for the chlorobenzene of low concentration.Thus, the catalyst among the present invention can be widely used in the catalytic combustion elimination of variable concentrations (organic pollution that comprises low concentration and high concentration) chlorine-containing volatile arene.
Embodiment 12
Change every gram catalyst and per hour handle the amount of waste gas, reaction pressure is at 0.1Mpa, and the concentration of chlorobenzene is 0.1vol%, use air to be oxidizing gas, on embodiment 6 catalyst, investigated of the influence of different air speeds to the chlorobenzene catalytic combustion properties, the results are shown in Table 4.
Table 4 air speed 88%Mn
2O
3-12%CeO
2The influence of catalyst combustibility
The result shows, 88%Mn
2O
3-12%CeO
2Exhaust-gas treatment amount hourly can be up to 3.15L/g catalyst (pressing 90% chlorobenzene by conversion calculations) down at 300 ℃ on the catalyst, and this commercial Application for catalyst is very crucial and important beyond doubt.
Embodiment 13
In the reaction unit of embodiment 9, the amount that every gram catalyst is per hour handled waste gas is 20L, is chlorine-containing volatile aromatic hydrocarbon with the chlorobenzene, and the concentration of chlorobenzene is 0.1vol%, and reaction temperature is 350 ℃ and investigates 88%Mn
2O
3-12%CeO
2Catalyst is in the heat endurance of reaction atmosphere.After the result showed 200h, the chlorobenzene conversion ratio did not detect polystream greater than 98% in the product.The commercial Application that this point is eliminated for the chlorine-containing volatile arene is particularly important, shows 88%Mn
2O
3-12%CeO
2Catalyst has bigger application prospect aspect the exhaust fume catalytic processing of industrial chlorine-containing volatile arene.
Claims (4)
1. one kind is used for the catalyst that the easy-to-volatile chloroarene low-temperature catalytic burning is eliminated, and this catalyst mainly is made up of one or several of appraise at the current rate transition metal M such as Cu, Fe, V, Mn, Mo, Co, W and rare earth oxide.The transition metal that appraises at the current rate is 50～90wt.% (oxide content), is preferably 70～90wt.%; Rare earth oxide is 10～50wt.%, is preferably 10～20wt.%.The transition metal that preferably appraises at the current rate is Mn, Cu, Fe; Preferred rare earth element is Ce and La.
2. the described Preparation of catalysts method of claim 1 is characterized in that: appraise at the current rate transition metal oxide and rare earth mixed oxide catalyst adopt the citric acid collosol and gel to make, and the rare earth element presoma is selected from the nitrate of rare earth; The presoma of transition metal is selected from nitrate, oxalates, acetate, the carbonate of metal M.
3. the described Preparation of catalysts method of claim 2, it is characterized in that: the rare earth nitrades and the transition metal presoma of metering are mixed, are dissolved in a certain amount of deionized water, add citric acid then, this solution places 80 ℃ constant temperature water bath to stir 6～7h; Put into 110 ℃ the dry 12h of drying box then, move in the roaster, temperature programming in air atmosphere, 4.2 ℃ of per minutes are raised to 550 ℃, and insulation 5h promptly gets described transition metal and the rare earth mixed oxide catalyst of appraising at the current rate of claim 2.
4. the low-temperature catalytic burning that is widely used in industrial waste gas, refuse, waste water easy-to-volatile chloroarene according to the described catalyst that is used for the elimination of easy-to-volatile chloroarene low-temperature catalytic burning of claim 1 is eliminated, especially the chloride arene pollutant of the effumability in the industrial waste gas.
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| CNA2008100372155A CN101279253A (en) | 2008-05-09 | 2008-05-09 | Catalyst for eliminating chlorinated aromatic hydrocarbons by low-temperature catalytic combustion |
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|---|---|---|---|
| CNA2008100372155A CN101279253A (en) | 2008-05-09 | 2008-05-09 | Catalyst for eliminating chlorinated aromatic hydrocarbons by low-temperature catalytic combustion |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107096526A (en) * | 2016-02-22 | 2017-08-29 | 江苏中科睿赛污染控制工程有限公司 | A kind of catalysis oxidation VOCs composite catalyst, preparation method and purposes |
| CN107149942A (en) * | 2016-11-30 | 2017-09-12 | 江苏安琪尔废气净化有限公司 | For the preparation method for the catalyst for being catalyzed burning polycyclic aromatic hydrocarbons (PAH) |
| CN107952441A (en) * | 2017-12-11 | 2018-04-24 | 大连理工大学 | A kind of preparation method and applications of propane catalysis burning composite oxide catalysts |
| CN108906044A (en) * | 2018-06-15 | 2018-11-30 | 中国科学院过程工程研究所 | A kind of manganese cerium ruthenium composite oxide catalysts and its preparation method and application |
| CN111744499A (en) * | 2020-06-19 | 2020-10-09 | 上海汇允环境科技有限公司 | Low-temperature catalytic oxidation VOCs catalyst and preparation method and application thereof |
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2008
- 2008-05-09 CN CNA2008100372155A patent/CN101279253A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107096526A (en) * | 2016-02-22 | 2017-08-29 | 江苏中科睿赛污染控制工程有限公司 | A kind of catalysis oxidation VOCs composite catalyst, preparation method and purposes |
| CN107149942A (en) * | 2016-11-30 | 2017-09-12 | 江苏安琪尔废气净化有限公司 | For the preparation method for the catalyst for being catalyzed burning polycyclic aromatic hydrocarbons (PAH) |
| CN107952441A (en) * | 2017-12-11 | 2018-04-24 | 大连理工大学 | A kind of preparation method and applications of propane catalysis burning composite oxide catalysts |
| CN108906044A (en) * | 2018-06-15 | 2018-11-30 | 中国科学院过程工程研究所 | A kind of manganese cerium ruthenium composite oxide catalysts and its preparation method and application |
| CN111744499A (en) * | 2020-06-19 | 2020-10-09 | 上海汇允环境科技有限公司 | Low-temperature catalytic oxidation VOCs catalyst and preparation method and application thereof |
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Open date: 20081008 |