CN104437486B - Catalytic combustion catalyst for hydrochloric ether and preparation method of catalytic combustion catalyst - Google Patents

Abstract

The invention relates to a catalytic combustion catalyst for chlorinated hydrocarbons and a preparation method thereof, which is a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms. Its preparation method is: dissolve aluminum salt, tin salt and barium salt in hydrochloric acid aqueous solution, add appropriate amount of malic acid and isobutanol, add glucose and chloroplatinic acid after constant temperature stirring, heat and reflux, rotary evaporation, after cooling to room temperature Add ammonia water dropwise until the pH value is 5.5-6.5, continue to stir and then let it stand for aging, filter and dry the filtrate, grind it, roast it in a box-type resistance furnace, and cool naturally to obtain Al ₂ O doped with platinum atoms _3. A composite material composed of SnO ₂ and BaO. Using the composite material provided by the invention as a catalytic combustion catalyst for chlorinated hydrocarbons, the conversion rate of chlorobenzene exceeds 55% at 200°C, and the T ₉₀ is about 250°C.

Description

Catalytic combustion catalyst for chlorinated hydrocarbons and preparation method thereof

technical field

The invention relates to a catalytic combustion catalyst for chlorinated hydrocarbons and a preparation method thereof, in particular to a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms, and belongs to the technical field of environmental protection.

Background technique

Catalytic combustion is a combustion reaction in which combustibles are carried out under certain temperature conditions under the action of a catalyst. Compared with direct combustion, the catalytic combustion temperature is lower and the combustion is more complete. As an important organic solvent and product intermediate, chlorinated organic compounds are widely used in many industries, but they are often carcinogenic, teratogenic and mutagenic substances. Chlorine-containing organic waste gases (CVOCs) widely exist in the production processes of machinery, petrochemical, pharmaceutical, and paint decoration industries, and their emissions will cause serious harm to the atmospheric environment and human health. Common CVOCs treatment methods include direct combustion method, photocatalysis method, solvent absorption method, catalytic combustion method, etc. Among them, the catalytic combustion method has low ignition temperature, low energy consumption, convenient industrial application and effective avoidance of secondary pollution in the treatment of CVOCs. It is considered to be one of the effective methods to control CVOCs due to the advantages of producing highly toxic substances such as CVOCs. It has been reported in the literature that V ₂ O ₅ /TiO ₂ catalysts show good catalytic activity and chlorine poisoning resistance in the treatment of chlorobenzene, dichlorobenzene and other aromatic hydrocarbons CVOCs, but the selectivity to CO ₂ is not high. It is easy to produce a large amount of CO; in addition, V ₂ O ₅ /TiO ₂ is difficult to completely convert dichloromethane, dichloroethane and other relatively stable alkane chlorides under low temperature conditions, and it is easy to generate monochloromethane in the combustion process , formaldehyde and other harmful intermediate products, causing secondary pollution. In the catalytic combustion of chlorine-containing organic waste gas, not only is the catalyst required to have high activity and stability, but it is also necessary to avoid a large amount of harmful intermediate substances such as CO and methylene chloride.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a catalyst with higher catalytic oxidation activity to chlorinated hydrocarbons and a preparation method thereof. The catalytic combustion catalyst of chlorinated hydrocarbons of the present invention is a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms, and its preparation method is:

Co-dissolve aluminum salts, tin salts and barium salts that are easily soluble in acidic aqueous solutions in hydrochloric acid aqueous solution with a mass fraction of 10-20%, add appropriate amount of malic acid and isobutanol, and stir at a constant temperature of 40°C for 2-3 hours , then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 3-5 hours, and rotate to evaporate one-third of the water. After cooling down to room temperature, add dropwise ammonia water with a mass fraction of 20% until the pH value is 5.5-6.5, and continue stirring for 1- After 2 hours, stand and age for 5-6 hours, filter and dry the filtrate, grind it, then heat up to 220-240°C at a speed of no more than 3°C per minute in a box-type resistance furnace, and keep this temperature for 4 -5 hours, continue to heat up to 480-495°C at a rate of no more than 3°C per minute, keep this temperature for 2-3 hours, and cool naturally to obtain a composite composed of platinum atoms doped Al ₂ O ₃ , SnO ₂ and BaO Material.

Among them, the aluminum salt is one or more mixtures of anhydrous or hydrates of aluminum nitrate, aluminum sulfate, aluminum perchlorate, aluminum phosphate, aluminum chloride and aluminum acetate, and the tin salt is tin chloride, tin chloride One or more mixtures of stannous, stannous nitrate and stannous sulfate anhydrate or hydrate, barium salt is one or two mixtures of barium chloride and barium nitrate anhydrate or hydrate .

When the mass fraction of each component of the prepared composite material satisfies Pt (3-5%), Al ₂ O ₃ (28-35%), SnO ₂ (32-40%) and BaO (25-30%), it can be As an efficient catalytic combustion catalyst for chlorinated hydrocarbons.

detailed description

Example 1

Co-dissolve aluminum nitrate nonahydrate, tin chloride pentahydrate and barium chloride, which are easily soluble in acidic aqueous solution, in aqueous hydrochloric acid solution with a mass fraction of 15%, add appropriate amount of malic acid and isobutanol, and stir at a constant temperature at 40°C 2 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 4 hours, rotary evaporate one-third of the water, drop to room temperature and add ammonia water with a mass fraction of 20% until the pH value is 6, continue to stir for 1 hour and then statically Leave it to age for 5 hours, filter and dry the filtrate, grind it, then raise the temperature to 230°C in a box-type resistance furnace at a speed of no more than 3°C per minute, keep this temperature for 4 hours, and continue at a rate of no more than 3°C per minute. The temperature was raised to 490°C at a rate of 3°C, maintained at this temperature for 2 hours, and cooled naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms.

Analysis: Composition analysis of the composite material shows that the mass percentages are 4.1% Pt, 28.7% Al ₂ O ₃ , 37.2% SnO ₂ and 30.0% BaO.

Application: The composite material is used as a catalytic combustion catalyst for chlorinated hydrocarbons. The conversion rate of chlorobenzene at 200°C is 56.7%, and the conversion rate of chlorobenzene at 250°C is 89.8%.

Example 2

Co-dissolve aluminum sulfate octadecahydrate, stannous chloride dihydrate and barium nitrate, which are easily soluble in acidic aqueous solution, in aqueous hydrochloric acid solution with a mass fraction of 17%, add appropriate amount of malic acid and isobutanol, and keep the temperature at 40°C Stir for 3 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 3 hours, rotate to evaporate one-third of the water, drop to room temperature and add ammonia water with a mass fraction of 20% to pH 5.6, continue stirring for 1.5 hours Stand and age for 6 hours, filter, dry and grind the filtrate, raise the temperature to 224°C in a box-type resistance furnace at a rate of no more than 3°C per minute, keep this temperature for 5 hours, and continue at a rate of no more than 3°C per minute. The temperature was raised to 484°C at a speed of more than 3°C, maintained at this temperature for 3 hours, and cooled naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms.

Analysis: Composition analysis of the composite material shows that the mass percentages are 3.6% Pt, 31.4% Al ₂ O ₃ , 35.5% SnO ₂ and 29.5% BaO.

Application: The composite material is used as a catalytic combustion catalyst for chlorinated hydrocarbons. The conversion rate of chlorobenzene at 200°C is 58.2%, and the conversion rate of chlorobenzene at 250°C is 90.7%.

Example 3

Co-dissolve aluminum perchlorate nonahydrate, stannous nitrate and barium chloride, which are easily soluble in acidic aqueous solution, in aqueous hydrochloric acid solution with a mass fraction of 19%, add appropriate amount of malic acid and isobutanol, and stir at a constant temperature of 40°C 3 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 5 hours, rotary evaporate one-third of the water, drop to room temperature and add ammonia water with a mass fraction of 20% until the pH value is 5.8, continue to stir for 2 hours and then statically Leave it to age for 5 hours, filter and dry the filtrate, grind it, then raise the temperature to 228°C in a box-type resistance furnace at a rate of no more than 3°C per minute, keep this temperature for 4 hours, and continue at a rate of no more than 3°C per minute. The temperature was raised to 487°C at a rate of 3°C, maintained at this temperature for 2 hours, and cooled naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms.

Analysis: Composition analysis of the composite material shows that the mass percentages are 3.3% Pt, 33.6% Al ₂ O ₃ , 39.2% SnO ₂ and 23.9% BaO.

Application: The composite material is used as a catalytic combustion catalyst for chlorinated hydrocarbons. The conversion rate of chlorobenzene at 200°C is 54.8%, and the conversion rate of chlorobenzene at 250°C is 89.5%.

Example 4

Co-dissolve aluminum phosphate, aluminum chloride hexahydrate, stannous sulfate and barium nitrate hydrate, which are easily soluble in acidic aqueous solution, in aqueous hydrochloric acid solution with a mass fraction of 11%, add appropriate amount of malic acid and isobutanol, and heat at 40°C Stir at constant temperature for 2.5 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 3 hours, and rotate to evaporate one-third of the water. After cooling down to room temperature, add ammonia water with a mass fraction of 20% until the pH value is 6.2, and continue stirring for 2 hours. After standing and aging for 6 hours, filter and dry the filtrate, grind it, then heat up to 237°C at a speed of no more than 3°C per minute in a box-type resistance furnace, keep this temperature for 5 hours, and continue to Raise the temperature to 491°C at a speed not exceeding 3°C, maintain this temperature for 3 hours, and cool naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms.

Analysis: Composition analysis of the composite material shows that the mass percentages are 4.8% Pt, 32.8% Al ₂ O ₃ , 33.7% SnO ₂ and 28.7% BaO.

Application: The composite material is used as a catalytic combustion catalyst for chlorinated hydrocarbons. The conversion rate of chlorobenzene at 200°C is 60.4%, and the conversion rate of chlorobenzene at 250°C is 91.3%.

Example 5

Co-dissolve aluminum acetate dihydrate, stannous chloride, stannous nitrate and barium nitrate, which are easily soluble in acidic aqueous solution, in aqueous hydrochloric acid solution with a mass fraction of 13%, add appropriate amount of malic acid and isobutanol, Stir at constant temperature for 2 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 4 hours, rotate to evaporate one-third of the water, drop to room temperature, add ammonia water with a mass fraction of 20% to pH 6.4, and continue stirring for 1 hour After standing and aging for 5 hours, filter and dry the filtrate, after grinding, heat up to 232°C at a speed of no more than 3°C per minute in a box-type resistance furnace, keep this temperature for 4 hours, and continue to Raise the temperature to 494°C at a speed not exceeding 3°C, keep this temperature for 2 hours, and cool naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms.

Analysis: Composition analysis was carried out on the composite material, and the measured mass percentages were 4.5% Pt, 34.5% Al ₂ O ₃ , 34.1% SnO ₂ and 26.9% BaO.

Application: The composite material is used as a catalytic combustion catalyst for chlorinated hydrocarbons. The conversion rate of chlorobenzene at 200°C is 58.5%, and the conversion rate of chlorobenzene at 250°C is 89.9%.

Claims (3)

1. The catalytic combustion catalyst of chlorinated hydrocarbons is characterized in that it is a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms, wherein the mass percent of each component is 3-5% Pt, 28-35 %Al ₂ O ₃ , 32-40% SnO ₂ and 25-30% BaO, the preparation method is: co-dissolving aluminum salt, tin salt and barium salt which are easily soluble in acidic aqueous solution in 10-20% Add an appropriate amount of malic acid and isobutanol to the hydrochloric acid aqueous solution, stir at a constant temperature of 40°C for 2-3 hours, then add an appropriate amount of glucose and chloroplatinic acid, heat and reflux for 3-5 hours, and rotate to evaporate one-third of the water. After cooling down to room temperature, add ammonia water with a mass fraction of 20% until the pH value is 5.5-6.5, continue to stir for 1-2 hours, then let it stand for 5-6 hours, filter and dry the filtrate, grind it, and put it in the oven In the electric resistance furnace, the temperature is raised to 220-240°C at a speed of no more than 3°C per minute, and the temperature is maintained for 4-5 hours, and the temperature is continued to be raised to 480-495°C at a speed of no more than 3°C per minute, and the temperature is maintained for 2- After 3 hours, cool naturally to obtain a composite material composed of Al ₂ O ₃ , SnO ₂ and BaO doped with platinum atoms. 2. the preparation method of the catalytic combustion catalyst of chlorinated hydrocarbon, it is characterized in that aluminum salt, tin salt and barium salt that are easily soluble in acidic aqueous solution are dissolved in the hydrochloric acid aqueous solution of 10-20% by mass fraction, add appropriate amount of malic acid and isobutanol, stirred at a constant temperature of 40°C for 2-3 hours, then added an appropriate amount of glucose and chloroplatinic acid, heated to reflux for 3-5 hours, rotary evaporated one-third of the water, and dropped the mass fraction after cooling down to room temperature 20% ammonia water until the pH value is 5.5-6.5, continue to stir for 1-2 hours, then stand and age for 5-6 hours, filter and dry the filtrate, grind it, and put it in a box-type resistance furnace at a rate of 1 minute per minute. Raise the temperature to 220-240°C at a speed exceeding 3°C, keep this temperature for 4-5 hours, continue to raise the temperature to 480-495°C at a speed of no more than 3°C per minute, keep this temperature for 2-3 hours, and naturally cool to obtain platinum. Composite material composed of atom-doped Al ₂ O ₃ , SnO ₂ and BaO. 3. the catalytic combustion catalyst of chlorinated hydrocarbon according to claim 1 is characterized in that described aluminum salt is the anhydrous matter of aluminum nitrate, aluminum sulfate, aluminum perchlorate, aluminum phosphate, aluminum chloride and aluminum acetate or a mixture of one or more hydrates, tin salts are anhydrous or hydrates of tin chloride, stannous chloride, stannous nitrate and stannous sulfate or a mixture of one or more hydrates, barium salts are One or two mixtures of the anhydrate or hydrate of barium chloride and barium nitrate.