Nanostructured catalyst for after-burning of carbon monooxide
SUBSTANCE: claimed invention relates to catalysts from metals of platinum group on oxide carrier, intended for removal of harmful components, in particular of gaseous carbon monoxide in engine exhaust fumes of automobile engines or for application in electrodes of gas-sensitive sensors, in fuel elements, which work on synthesis-gas, and in other electrochemical devices. Described is nano-structured catalyst for after-burning of carbon monoxide, which as carrier contains tin dioxide, alloyed with antimony oxide with ratio of antimony to tin being 2 mol % and particles of nano-crystalline platinum, content of which in catalyst constitutes 2 wt %, with oxide carrier having one-phase composition, and particles of nano-crystalline platinum, precipitated on oxide carrier, have size 3-5 nm.
EFFECT: obtaining highly active catalyst for carbon monoxide oxidation.
The invention relates to catalysts of the platinum group metals on the oxide carrier, designed to remove harmful components, in particular gaseous carbon monoxide in the exhaust gases of automobile engines or for use in the electrodes of the gas-sensitive sensors, fuel cells operating on sines gas, and other electrochemical devices.
Described is a catalyst for afterburning of carbon monoxide, in which the platinum group metals are fixed on the carrier - antimony-doped tin dioxide. The technical result is to obtain highly active catalysts for deep oxidation of carbon monoxide.
Examples besplatnih catalysts for oxidation of carbon monoxide in the presence of hydrogen by oxidation with oxygen or air are selective catalysts based on copper or manganese, comprising as an active ingredient CuO-CeO2or MnO2-CeO2with the content of CuO or MnO21-10 wt.% as in massive form and deposited on oxides of aluminum, zirconium, silicon, and/or compounds based on them, or graphite-like carbon material.
For example, it is known [USSR Author's certificate No. 844038, the Catalyst for the neutralization of the engine exhaust gases, 1981] in the catalyst for the afterburning of the exhaust gas is, containing carbon monoxide with drawing on Al2O3oxides of cobalt and copper from aqueous solution, drying and calcination in air. The main disadvantage of the catalysts obtained by the application of active component such media, is that the most active components interact with Al2O3with the formation of aluminates, the activity of which is lower than the source of the oxides of cobalt and copper.
As catalysts based on noble metals, use of the system, in which the active component is applied platinum, palladium, ruthenium, rhodium, iridium mainly ruthenium and platinum, deposited (in the amount of 0.05-5 wt.%) on carbon carriers or oxide materials such as oxides of aluminum, zirconium, cerium, silicon and/or compounds based on them. More often as precious metal ternary catalysts use platinum. However, when using platinum group metals when exposed to high temperature exhaust gas for a long period of time platinum particles increase in size, and, thus, the specific surface area of each of the platinum particles is reduced, reducing the activity of the catalyst.
Known catalyst [RF Patent №2386533, the Method of receiving nanocatalysts oxidation of carbon monoxide, 2008, containing 95-98% of aluminum oxide and nanesennykh him nanoparticles of platinum metals (2-5%).
Of the known catalysts of similar essential features is the catalyst described in patent [U.S. Patent 4136059, Method for producing highly dispersed catalytic platinum, 1979], selected as a prototype. Method of preparation of the catalyst consists in the application of platinum on a carbon carrier from the colloidal solution in the presence of dithionite sodium, followed by reduction with formic acid. The disadvantages of such catalysts and similar when used in commercial electrochemical gas sensors CO should be attributed to the low selectivity of CO sensors (sensitivity SCO/SH2does not exceed 5-8). The use of such catalyst for oxidation of carbon monoxide to carbon dioxide is inefficient due to the low rate of oxidation of carbon monoxide in the temperature range of 0-150°C. additionally, in such systems, the decrease of the active surface of the catalyst due to sintering of platinum particles.
To prevent agglomeration effect and increase the selectivity of the catalysts is proposed to use as the material of the carrier for the catalyst - doped tin dioxide. Surface properties SnO2depend on the synthesis conditions, and the nature and kolichestvennymi additives. These factors determine the nature of the interaction surface of the working electrode with gas. Alloying additives can reduce the tendency of the platinum catalyst to agglomerate. The most active oxidizing catalyst is Pt, but the temperature oxidation of CO is 200°C due to the strong chemisorption of gas on platinum at lower temperatures. An important task is the creation of bifunctional platinum catalyst, which would possess the efficiency of the oxidation of CO at low temperatures.
The technical purpose of this invention to provide a high level of nanostructured catalytic afterburning of carbon monoxide with high specific surface area and efficiency when used in the oxidation reaction of carbon monoxide to carbon dioxide.
The solution of this problem in the proposed nanostructured catalyst for afterburning of carbon monoxide is due to the fact that the catalyst contains one or more catalytically active platinum group metals (such as Pt or Ru) on the conductive oxide carrier that provides high catalytic activity, thus to obtain a high specific surface electrocatalysts as media use doped with antimony oxide deoxycolate with a specific surface area of about 60 m 2/g and the content of the oxide carrier in the catalyst is 98 wt.%. Due to the fact that the oxide carrier has a single-phase composition, and the ratio of the elements in the oxide carrier Sb/Sn=0.02 is provided by the high electronic conductivity. The average particle size of platinum group metals is 3-5 nm.
The proposed nanostructured catalyst is a platinum nanoparticles deposited on the oxide carrier consisting of tin dioxide doped with antimony.
Synthesis nanostrukturirovannogo catalyst takes place in two stages. At the first stage by the method of reverse micelles synthesized media. For this metal salts SnCl4and SbCl3dissolve in cyclohexane containing an appropriate amount of surfactant (cetyltrimethylammonium bromide (BECOMING)add NaOH and after thorough mixing, leave for days for the formation of the oxide particles. The materials obtained were annealed in air at 400°C.
At the second stage, the catalyst composition is administered platinum by the following method: to the oxide carrier poured glycol and dispersed in the ultrasound. Then in the resulting suspension add NaOH and stirred until complete dissolution of sodium hydroxide. Then add the platinum precursor. The mixture with constant stirring videris the Ute at a temperature of 130°C in an inert atmosphere, then dried in a vacuum Cabinet at a temperature of 80°C.
Nanostructured catalyst is a platinum nanoparticles deposited on the oxide carrier consisting of tin dioxide doped with antimony (Pt content is 2 wt.%, and the content of Sb/Sn=2 mol.%)
The synthesis of the catalyst took place in two stages. At the first stage by the method of reverse micelles synthesized media. For this metal salts SnCl4, SbCl3was dissolved in cyclohexane containing an appropriate amount of surfactant (cetyltrimethylammonium bromide (BECOMING), was added NaOH to pH=13 and after thorough mixing left on the clock for the formation of the oxide particles. The obtained materials were annealed in air for 1 hour at a temperature of 400°C.
At the second stage, the catalyst composition is administered platinum. To 2 g of the oxide carrier was added 500 ml of ethylene glycol and dispersible in ultrasound. Then the resulting suspension was added NaOH (to pH~13) and stirred until complete dissolution of sodium hydroxide. Then added the platinum precursor with a rate of 2 wt.% platinum in relation to the mass media. The obtained mixture under stirring was kept at a temperature of 130°C in an inert atmosphere, and then dried in a vacuum Cabinet at a temperature of 80°C for 12 hours.
Oxide media, part of which has been received is of talesfore, has retinopathy structure. The content of platinum in nanocatalysts is about 2 wt.%, the average particle diameter of platinum - 3 nm. Specific active surface of the catalyst is 68 m2/g Pt. The initial temperature oxidation of CO is 80°C, and the temperature of complete conversion of CO to 180°C.
Nanostructured catalyst is a platinum nanoparticles deposited on the oxide carrier consisting of tin dioxide doped with antimony was synthesized by the method described in example 1 and was characterized by the fact that the content of Pt in the catalyst was 2.5 wt.%, and the Sb content in the oxide carrier to 2.5 mol.%.
Oxide carrier included in the composition of the obtained catalyst has retinopathy structure. The content of platinum on the carrier is about 2.5 wt.%, the average diameter of the platinum particles is 5 nm. Specific active surface of the catalyst, determined from desorption of carbon monoxide is 65 m2/g Pt.
Nanostructured catalyst for afterburning of carbon monoxide containing as a carrier of tin dioxide doped with antimony oxide in the ratio of antimony to tin 2 mol.%, and particles of nanocrystalline platinum content in the catalyst is 2 wt.%, wherein the oxide carrier has a single-phase composition, and besieged the oxide and the carrier particles of nanocrystalline platinum have a size of 3-5 nm.
SUBSTANCE: invention relates to medicine, namely to general surgery, and can be applied in prevention of purulent-inflammatory complications of anterior abdominal wall wounds in case of strangulated ventral hernias. For this purpose, 10% solution of colloidal nanosilver is introduced into operation wound after elimination of strangulation, with preliminary injections on perimetre of hernial orifice edges in dose 0.1 ml of solution per 1 cm2 of aponeurosis. After that, after fixation of synthetic implant, injections are made along the line of sutures on periphery in dose 0.1 ml per 1 cm2 of suture. After that, subcutaneous adipose cellular tissue is infiltrated with solution of colloidal nanosilver in dose 0.1 ml of solution per 1 cm2 of wound.
EFFECT: method ensures considerable reduction of risk of development of purulent-inflammatory complications in patients with said pathology, as well as acceleration of processes of tissue reparation due to application of biologically active colloidal solution of nanosilver, producing selective impact only on pathogenic microorganisms, on all layers of anterior abdominal wall and zone of synthetic implant fixation.
5 cl, 1 ex
SUBSTANCE: method involves subsequent vacuum deposition of metal and graphite on a substrate. Metal is deposited by thermal evaporation, and graphite is deposited by evaporation with a pulse arc discharge and deposition by means of compensated non-current foreclusters of carbon plasma with density of 5·1012-1·1013 cm-3, duration of 200-600 mcs, repetition frequency of 1-5 Hz, which is stimulated during deposition by inert gas in the form of an ion flow with energy of 150-2000 eV, which is directed perpendicular to flow of plasma foreclusters. After deposition is completed, annealing of the substrate is performed in nitrogen medium at the temperature of 150-500°C during 1-10 min. With that, a substrate from silicon with proper conductivity is used; and as metal, the metal chosen from the group containing cadmium is used; and composition from silver and nickel, and composition from silver, nickel and cadmium is used.
EFFECT: improving functional properties of material; enlarging the range of produced photo-sensitive nanomaterials.
13 dwg, 6 ex
SUBSTANCE: invention proposes a production method of a nanosized delivery system of fragments of nucleic acids (FNA) and their analogues to cells of mammals. A suspension of TiO2 nanoparticles with concentration of 1-2 mg/ml in 0.1-0.5 M solution of NaCl is obtained. With that, TiO2 particles have the size of 3-20 nm, and mainly 3-5 nm, and are contained in amorphous or crystalline anatase or brookite form. The obtained TiO2 suspension is mixed with water solution of polylysin with concentration of 20 mg/ml in the ratio of TiO2 to polylysin, which is equal to 1:(0.05-0.8). The mixture is incubated at room temperature during at least 30 minutes. Then, to the obtained suspension of polylysin-containing nanoparticles there added is 5-70 mcL of FNA solution with concentration of 10-4-10-7 M and incubated in 0.1-0.5 M solution of NaCl at room temperature during 20-30 minutes. Nanocomposite TiO2-PL FNA with capacity as per FNA of 0.2-60 nmol/mg is obtained.
EFFECT: invention allows simplifying a production method of FNA delivery system and shortening its duration.
4 cl, 3 dwg, 14 ex
SUBSTANCE: method involves selecting a dispersion phase of an electrorheological suspension based on polyimide nanoparticles by simulation. Simulation involves constructing and optimising the structure of various oligomers and constructing the initial nanoscopic model of the elementary volume of the electrorheological liquid. An electric field is simulated by two planes and all molecular systems are situated strictly in between. Further, polyimides are synthesised by single-step high-temperature polycondensation of diamines and dianhydrides of tetracarboxylic acids with acylation and polycyclisation steps in a high-boiling solvent. Experimental testing of electrorheological suspension based on the modified polyimides is then carried out.
EFFECT: invention enables to obtain electrorheological suspensions with improved process, rheological properties and strong electrorheological response.
12 cl, 10 dwg
SUBSTANCE: method involves mixing equally concentrated, highly saponified aqueous solutions of polyvinyl alcohol and partially saponified polyvinyl alcohol and filler, where the filler is nano-bodies selected from fullerenes and nanotubes, taken in amount of 0.02-1.0 wt % with respect to the polymer.
EFFECT: combining two types of polyvinyl alcohol to obtain mixed compositions.
SUBSTANCE: invention refers to medicine, namely purulent surgery, and may be used for treating infected wounds. That is ensured by surgical treatment of suppurative focuses and exsection of necrotised tissues. Then the whole wound surface is treated with 10% colloidal nanosilver. The subcutaneous fat is infiltrated with 10% colloidal nanosilver at 0.1 ml of the solution per 1 cm2 of the wound. Additionally, the wound is covered with a sterile 10% colloidal nanosilver wipe.
EFFECT: method enables reducing the length of wound granulation and epithelisation ensured by using the biologically active colloidal nanosilver solution coating all wound layers and rendering selective action on pathogens only.
SUBSTANCE: in method for manufacturing of MIS-nanotransistor with local area for buried insulation at surface of silicone substrate of the first type of conductivity an insulating layer is formed around active regions of the transistor, a groove is formed as a basis for a stepped relief; then the first near-wall region and layer mask is formed, implantation of ions, mainly of oxygen, is performed till a layer with high concentration of oxygen and silicone oxide atoms is formed; the second near-wall region is formed, then implantation of ions of the second type is made here components with atoms with higher oxides are used which form glass with silicon dioxide; while thin buried insulation layer and active drain and source regions are formed simultaneously by annealing at temperature higher than softening point but less than glass transition temperature; for the purpose of drains and source regions insulation from each other an isolation channel is formed and insulating layer is applied to its surface; terminating regions are formed.
EFFECT: manufacturing process that allows manufacturing of MIS-nanotransistors without use of high-resolution lithography with maximum reduction of short-channel effect.
1 ex, 4 dwg
SUBSTANCE: method of multilayer gate structure manufacturing for field controlled transistors (FETs) includes formation of metal-containing layer directly at the first layer of TiN, titanium nitride, that covers areas of semiconductor substrate purposed for FETs of the first and second type; formation of protective coating by application of the second TiN-layer on top of the metal-containing layer; pattern generation at the second TiN-TiN-layer and metal-containing layer in order to cover only the first part of the first TiN-layer that covers the area designed for FETs of the first type; etching of the second part for the first TiN-layer which remains opened during pattern generation while the first part of the first TiN-layer is protected from etching due to its closure by part of the metal-containing layer with generated pattern; and formation of the third TiN-layer that covers the area of semiconductor substrate designed for FETs of the second type.
EFFECT: perfection of manufacturing technology for a multilayer gate structure.
27 cl, 9 dwg
SUBSTANCE: multifunctional scanning probe microscope comprises: a base (1); an approach unit (3) movably mounted on the base (1); a piezoscanner (4) situated on the preliminary approach unit (3); an object holder (5) situated on the piezoscanner (4); a sample (6) which comprises a measuring area (M) and is attached to the piezoscanner (4) by the object holder (5); a platform (9) attached to the base (1) opposite the sample (6); and an analyser mounted on the platform (9) and comprising a first measuring head (13) facing the sample (6) and adapted for probing the measuring area (M) of the sample (6). The microscope also has first and second guides (10, 11) fastened to the platform (9). The analyser has a second measuring head (16) facing the sample (6) and adapted for probing the measuring area (M) of the sample (6). The first and second measuring heads (13, 16) are movably mounted on the first and second guides (10, 11) respectively.
EFFECT: enabling fast change of measurement modes.
15 cl, 14 dwg
FIELD: measurement equipment.
SUBSTANCE: in pressure measuring method using a resistive strain-gauge pressure sensor based on a nano- and microelectromechanical system (NiMEMS), in the measurement mode, the measured pressure value Pi is calculated by means of biharmonic spline interpolation as per control points, based on column vector W(Pe, UiZ, Upt, X1…Xn) saved at calibration stage by the following formula: Pi=GT×W, where GT - transposed column vector G; symbol "×" means matrix product. Calibration for pressure measurement is performed by recording of stresses of measurement Uiz and feed Upt diagonals of a bridge measurement chain and values X1…Xn, depending on destabilising factors, and by writing to a read-only memory of the sensor of column vector W, which is calculated as per the following formula: W=g-1×P, where P - column vector of reference values of pressure at control points; g - matrix, the elements of which are defined depending on the number of variables of conversion function. Pressure sensor based on NiMEMS, which implements the proposed measurement and calibration methods, includes a current sensor, a resistive strain-gauge pressure converter, ADC, a calculating device, a read-only memory and a digital interface. With that, the calculation device consists of a conversion unit of ADC code to a numerical voltage value, and a calculation unit of numerical pressure value.
EFFECT: improvement of pressure measurement accuracy.
3 cl, 4 dwg, 4 tbl
FIELD: process engineering.
SUBSTANCE: invention relates to methods of making catalysts, preferably for ICE exhaust cleaners. Proposed method comprises impregnating inert carrier with the mix of organic solutions of compounds of europium and/or cerium, platinum and/or palladium and bismuth, stripping of organic solution and high-temperature treatment of inert carrier at 820-870°C. Used organic solutions represent extracts of compounds of europium and/or cerium, platinum and/or palladium and bismuth to be mixed in preset ratio that allows for the following content of catalyst in active solid phase: oxides of europium and/or cerium - 96-98 wt %, oxide of platinum and/or palladium - 0.5-2 wt %, and bismuth oxide - 1.5-2 wt %.
EFFECT: higher adhesion between active layer with inert carrier surface, higher efficiency and longer life of catalyst.
7 cl, 9 ex
FIELD: petroleum processing and catalysts.
SUBSTANCE: invention relates to bismuth- and phosphorus-containing catalyst carriers, petroleum reforming catalysts prepared on these carriers, to methods for preparing both carriers and catalysts, and to petroleum reforming process using these catalysts. Described are catalyst carrier containing γ-alumina particles wherein bismuth and phosphorus are distributed essentially uniformly in catalytically efficient concentrations and a method for preparation thereof comprising (a) preparing solution containing bismuth precursor and solution containing phosphorus precursor; (b) preparing γ-alumina/alumina sol mixture; (c) mixing mixture of step (b) with solutions prepared in step (a) to produce carrier precursor containing essentially uniformly distributed phosphorus and bismuth; (d) molding; and (e) drying and calcination. Invention also describes petroleum reforming catalyst containing above-defined carrier and catalytically efficient amount of platinum, chlorine, and optionally rhenium; method of preparation thereof; and petroleum reforming process after hydrofining, which involves contacting petroleum with above-defined catalyst in presence of hydrogen at elevated temperature and pressure.
EFFECT: reduced catalyst coking velocity and achieved high stable activity of catalyst.
25 cl, 6 dwg, 4 tbl, 10 ex
FIELD: petroleum processing catalysts.
SUBSTANCE: catalyst containing platinum, rhenium, antimony, and chlorine on alumina are prepared by impregnation of carrier with aqueous solution of compounds of indicated elements, antimony being deposited as first or second component. Once antimony or platinum-antimony combination, or rhenium-antimony combination deposited, catalyst is dried at 130°C and then calcined in air flow at 500°C. Reduction of catalyst is performed at 300-600°C and pressure 0.1-4.0 MPa for 4 to 49 h. After deposition of antimony or two elements (platinum-antimony or rhenium-antimony) and drying-calcination procedures, second and third or only third element are deposited followed by drying and calcination. Final reduction of catalyst is accomplished in pilot plant reactor within circulating hydrogen medium at pressure 0.3-4.0 MPa and temperature up to 600°C for a period of time 12 to 48 h.
EFFECT: enhanced aromatization and isomerization activities of catalyst and also its stability.
2 cl, 1 tbl, 8 ex
SUBSTANCE: invention relates to an improved method of preventing precipitation of a catalyst system when producing acetic acid via carbonylation of methanol and/or reactive derivative thereof with carbon monoxide in at least one carbonylation reaction zone, containing a liquid reaction composition containing an iridium carbonylation catalyst, a methyl iodide cocatalyst, water in an a limited concentration, acetic acid, methyl acetate and boron and gallium as promoters.
EFFECT: combination of boron and gallium as promoters enables to avoid problems with precipitation which are observed in ruthenium-promoted reactions, and the rate of reaction also remains the same compared with conventional ruthenium promoters.
15 cl, 2 tbl, 1 ex
FIELD: oil and gas industry.
SUBSTANCE: invention refers to the formed catalyst with specified high density and with specified low ratio of platinum group component to stannum, and deals with application method of catalyst for conversion of hydrocarbons. There described is conversion catalyst of hydrocarbons, which includes platinum group metal, stannum and substrate, and has average bulk density which is more than 0.6 g/cm3, and preferably more than 0.65 g/cm3, in which mass ratio of platinum group metal to stannum is less than 0.9, and preferably less than 0.85, where platinum is platinum group metal in amount of 0.01 to 2.0 wt %, on a per element basis, and where the above catalyst includes associated stannum in specific clusters from stannum and metals of platinum group in quantity of at least 33 wt %, and effective molar ratio of associated stannum to platinum in the above clusters is at least 0.65 as per Moessbauer spectroscopy analysis. There also described is conversion method of hydrocarbons, which involves contact of hydrocarbon material with the above catalyst at conversion conditions of hydrocarbons, converted hydrocarbon, where catalyst includes metal of platinum group, stannum and substrate, has average bulk density which is more 0.6 g/cm3, where mass ratio of metal of platinum group to stannum is less than 0.9.
EFFECT: technological advantages of conversion of hydrocarbon material.
10 cl, 3 ex, 6 tbl
SUBSTANCE: invention relates to a catalyst system and a method of reducing nitrogen oxide emissions. The described catalyst system for reducing NOx contains: a catalyst having a support which contains at least one compound selected from a group consisting of aluminium oxide, titanium dioxide, zirconium dioxide, cerium oxide, silicon carbide and mixtures thereof, a catalytic metal oxide containing at least one of gallium oxide or silver oxide and at least one activating metal selected from a group consisting of silver, cobalt, molybdenum, tungsten, indium or mixtures thereof; and a gas stream containing oxygen ranging from approximately 1 mol % to approximately 12 mol % and an organic reducing agent selected from a group consisting of alcohol, carbonate or combinations thereof, where the said organic reducing agent and the said NOx are present in molar ratio carbon: NOx ranging from approximately 0.5:1 to approximately 24:1. A catalyst system for reducing NOx which contains the following is described: a catalyst consisting of (i) metal oxide support which contains aluminium oxide, (ii) at least one of the following oxides: gallium oxide or silver oxide, present in amount ranging from approximately 5 mol % to approximately 31 mol %; and (iii) an activating metal or a combination of activating metals, present in amount ranging from approximately 1 mol % to approximately 22 mol % and selected from a group consisting of silver, cobalt, molybdenum, tungsten, indium and molybdenum, indium and cobalt, and indium and tungsten; and a gas stream containing (A) water in range from approximately 1 mol % to approximately 12 mol %; (B) oxygen in the range from approximately 1 mol % to approximately 15 mol %; and (C) an organic reducing agent containing oxygen and selected from a group consisting of methanol, ethanol, butyl alcohol, propyl alcohol, dimethyl carbonate or combinations thereof; where the said organic reducing agent and NOx are present in molar ratio carbon: NOx ranging from approximately 0.5:1 to 24:1. Also described are methods of reducing NOx which involve the following steps: providing a gas mixture and bringing the said gas mixture into contact with above described catalysts for reducing NOx (versions).
EFFECT: reduced ill effects of air contamination caused by by-products of incomplete high-temperature combustion of organic substances.
21 cl, 34 ex, 4 tbl
SUBSTANCE: invention relates to organic chemistry and petrochemistry, particularly to designing and using catalysts. Described is a catalyst for dehydrogenation of isopentane and isopentane-isoamylene fractions based on platinum and tin, deposited on a carrier - zincalume spinel. The catalyst is distinguished by that, the carrier is in form of nanocrystalline particles with average crystal size of 22-35 nm with components in the following ratio, wt %: platinum - 0.05-2.0, tin - 0.1-6.0, zincalume spinel - the rest. Also described is a method of preparing said catalyst, involving grinding and mixing oxygen-containing zinc and aluminium compounds, gradual addition of water until obtaining a homogeneous pasty mass, stirring and moulding, drying the granules at room temperature and calcination, subsequent saturation of the formed carrier with an aqueous solution of platinum and tin compounds, final drying of the catalyst mass in air; the method is distinguished by that, the carrier is calcined while gradually raising temperature to 800-900°C at a rate of 10-200°C/hour, and then for 5-40 hours at 850-1000°C, while constantly controlling size of the formed crystals until formation of nanocrystalline particles with average crystal size of 22-35 nm.
EFFECT: increased efficiency of dehydrogenation process due to increased output of isoprene, with high selectivity on dehydrogenation products, as well as due to longer inter-regeneration period of the catalyst.
3 cl, 1 tbl, 14 ex
SUBSTANCE: present invention refers to naphtha reforming catalyst. There is disclosed a catalyst effective in naphtha reforming involving particles of heat-resistant inorganic oxide carrier containing dispersed bivalent tin, platinum group metal and rhenium and optionally halogen, characterised that tin uniformly coats the catalyst, and platinum group metal uniformly coats the catalyst; tin is impregnated into the carrier with using tin chelate resulted from reaction of chelating agent representing amino acid and bivalent tin salts. There is also disclosed catalytic reforming of naphtha as feed stock, wherein feed stock contacts with said catalyst in reforming environment involving temperature 315°C-600°C, pressure 100 KPa - 7 MPa (abs.), liquid hourly space velocity 0.1-20 h-1, and molar ratio of hydrogen to naphtha feed stock 1-20.
EFFECT: new naphtha reforming catalyst and new catalytic reforming of naphtha.
10 cl, 2 dwg, 1 tbl, 6 ex
SUBSTANCE: present invention refers to catalytic system and to the method of reduction of nitrogen oxides emissions using the said system. The described catalytic system for NOx reduction contains: the catalyst containing the metal oxide substrate, catalytic metal oxide which is gallium oxide or silver oxide or both of them and initiating metal chosen from the group consisting of silver, cobalt, molybdenum, wolfram, indium, bismuth and their mixtures, gas flow containing the organic reducing agent and sulfur-containing substance. The described catalytic system for NOx reduction contains: the catalyst consisting of (i) the metal oxide substrate, containing aluminium oxide, (ii) catalytic metal oxide which is gallium oxide or silver oxide or both of them in quantity 1-31 mole %; and (iii) initiating metal or their combination selected from the group consisting of silver, cobalt, molybdenum, wolfram, indium, bismuth, indium and wolfram, silver and cobalt, indium and molybdenum, indium and silver, bismuth and silver, bismuth and indium and molybdenum and indium in quantity 1-31 mole %, gas flow containing (A) water in quantity 1-15 mole %; (B) gaseous oxygen in quantity 1-15 mole %; and (C) organic reducing agent selected from the group consisting of alcanes, alkenes, alcohols, ethers, esters, carboxylic acids, aldehydes, ketones, carbonates and their combinations; and sulfur oxide; where at the specified organic reducing agent and NOx are present in approximate molar ratio carbon to NOx from 0.5:1 to 24:1. The described method of NOx reducing includes the stages of gaseous mixture containing NOx, organic reducing agent and sulfur-containing substance inflow and of said gaseous mixture contact with specified catalyst. The described method of NOx reduction includes: inflow of gaseous mixture containing (A) NOx, (B) water in quantity 1-15 mole %; (C) oxygen in approximate quantity 1-15 mole %; (D) organic reducing agent selected from the group consisting of alcanes, alkenes, alcohols, ethers, esters, carboxylic acids, aldehydes, ketones, carbonates and their combinations and (E) sulfur oxide; and contact of said gaseous mixture with catalyst described above and containing the specified components in the defined molar ratio.
EFFECT: improved action of the catalyst.
35 cl, 10 tbl, 84 ex
SUBSTANCE: description is given of a method of obtaining olefins. The method involves passing a mixture of a hydrocarbon and oxygen containing gas through a catalyst zone, which is capable of maintaining burning over the upper limit the inflammability of the fuel, with obtaining of the above mentioned olefin. The catalyst zone consists of at least, a first layer of catalyst and a second layer of catalyst, where the second catalyst layer is put in the process line after the first catalyst layer, has different content from the first layer and has general formula: M1 aM2 bM3 cOz, where M1 is chosen from IIA, IIB, IIIB, IVB, VB, VIB, VIIB groups of lanthanides and actinoides, M2 is chosen from IIA, IB, IIB, IIIB, IVB, VB, VIB groups, and M3 is chosen from IIA, IB, IIB, IIIB, IVB, VB, VIB and VIIIB groups, a, b, c and z represent atomic ratios of the M1, M2, M3 and O components respectively. The value of a lies in the interval from 0.1 to 1.0, the value of b lies in the interval from 0.1 to 2.0, the value of c lies in the interval from 0.1 to 3.0, and the value of z lies in the interval from 0.1 to 9.0. The catalyst zone has a perovskite type structure.
EFFECT: perfection of the method of obtaining olefins.
9 cl, 4 tbl, 1 dwg, 4 ex
FIELD: petrochemical processes and catalysts.
SUBSTANCE: invention provides isodewaxing catalyst for petroleum fractions containing supported platinum and modifiers wherein supporting carrier is fine powdered high-purity alumina mixed with zeolite ZSM 5 in H form having SiO2/Al2O3 molar ratio 25-80 or with zeolite BETA in H form having SiO2/Al2O3 molar ratio 25-40 at following proportions of components, wt %: platinum 0.15-0.60, alumina 58.61-89.43, zeolite 5-40, tungsten oxide (modifier) 1-4, and indium oxide (modifier) 0.24-0.97. Preparation of catalyst comprises preparing carrier using method of competitive impregnation from common solution of platinum-hydrochloric, acetic, and hydrochloric acids followed by drying and calcinations, wherein carrier is prepared by gelation of fine powdered high-purity alumina with the aid of 3-15% nitric acid solution followed by consecutive addition of silicotungstenic acid solution and indium chloride solution, and then zeolite ZSM 5 in H form having SiO2/Al2O3 molar ratio 25-80 or with zeolite BETA in H form having SiO2/Al2O3 molar ratio 25-40.
EFFECT: increased yield of isoparaffin hydrocarbons.
7 cl, 2 tbl, 7 ex