146 results about "HCN poisoning" patented technology

An interlayer insulating film composed of an organic compound film containing an organic component as a main constituent is deposited on a semiconductor substrate. Then, etching is performed with respect to the interlayer insulating film by using a plasma derived from an etching gas containing an ammonia gas as a main constituent. As a result, active hydrogen is generated in the plasma derived from the ammonia gas to decompose the organic component into hydrogen cyanide, whereby etching proceeds. Since a surface of the organic compound film is efficiently nitrided by nitrogen generated from the ammonia gas, the sidewalls of a depressed portion in the organic compound film are protected so that an excellent anisotropic property is provided. Since the etching gas does not contain a component which oxidizes the organic compound film, the problem does not occur that a gas is generated from the organic compound film in a subsequent heat treatment process.

A process is described for preparing 3-pentenenitrile, characterized by the following process steps:

• (a) reacting 1,3-butadiene with hydrogen cyanide over at least one catalyst to obtain a stream 1 which comprises 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst and 1,3-butadiene,
• (b) distilling stream 1 in a column to obtain a high-1,3-butadiene stream 2 as the top product and a low-1,3-butadiene stream 3 as the bottom product which comprises 3-pentenenitrile, the at least one catalyst and 2-methyl-3-butenenitrile,
• (c) distilling stream 3 in a column to obtain a stream 4 as the top product which comprises 1,3-butadiene, a stream 5 which comprises 3-pentenenitrile and 2-methyl-3-butenenitrile at a side draw of the column, and a stream 6 as the bottom product which comprises the at least one catalyst,
• (d) distilling stream 5 to obtain a stream 7 as the top product which comprises 2-methyl-3-butenenitrile, and a stream 8 as the bottom product which comprises 3-pentenenitrile.

The invention provides a hydrocyanation process for the production of adiponitrile and other dinitriles having six carbon atoms, the process comprising:

• • a) forming a reaction mixture in the presence of at least one Lewis acid, said reaction mixture comprising ethylenically unsaturated nitrites having five carbon atoms, hydrogen cyanide, and a catalyst precursor composition, by continuously feeding ethylenically unsaturated nitrites, hydrogen cyanide, and a catalyst precursor composition;
  • b) controlling X and Z, wherein X is the overall feed molar ratio of 2-pentenenitriles to all unsaturated nitriles and Z is the overall feed molar ratio of hydrogen cyanide to all unsaturated nitrites, by selecting a value for X in the range from about 0.001 to about 0.5, and a value for Z in the range from about 0.5/1 to about 0.99/1, such that the value of quotient Q, wherein

is in the range from about 0.2 to about 10, wherein 3PN is 3-pentenenitriles and 4PN is 4-pentenenitrile; and

• • c) withdrawing a reaction product mixture comprising adiponitrile;
  • wherein the ratio of the concentration of 2-pentenenitriles to the concentration of 3-pentenenitriles in the reaction mixture is from about 0.2/1 to about 10/1;
  • wherein the catalyst precursor composition comprises a zero-valent nickel and at least one bidentate phosphite ligand; and

wherein the bidentate phosphite ligand is selected from a member of the group represented by Formulas I and 11 as described herein.

The subject invention is directed to a breath analyzer which is capable of detecting toxic gas levels from breath analysis. The subject invention includes a mouthpiece which is in communication with a plurality of discrete chambers, such as first and second discrete chambers, each being provided with a separate probe for breath analysis. The probes are connected to analyzers for determining detected levels of gas. In a first embodiment, a first probe may be provided for carbon monoxide detection with a second probe being provided for hydrogen cyanide detection. Advantageously, with this arrangement, breath analysis may be conducted on-site, for example at the site of a fire, to quickly and simultaneously determine carbon monoxide and hydrogen cyanide levels in a person's blood stream. In a second embodiment, a first probe may be provided for detection of carbon monoxide and a second probe may be provided for detection of hydrogen. With this arrangement, a calibrated correction of measured carbon monoxide data can be made to correct for improperly detected hydrogen. As such, a highly accurate on-site measurement for carbon monoxide can be achieved.

A process to prepare substantially pure glycolonitrile in an aqueous medium is provided by reacting hydrogen cyanide and formaldehyde. The formaldehyde feed stream is heated prior to reacting with hydrogen cyanide, resulting in an aqueous glycolonitrile solution with fewer impurities, especially less unreacted formaldehyde, than is obtained by other methods. The process enables production of an aqueous glycolonitrile solution that requires less post-reaction purification (if any at all) prior to enzymatically converting the glycolonitrile into glycolic acid.

A method for preparing 3-(methylthio)propanal and 2-hydroxy-4-(methylthio)butanenitrile by catalyzed addition of methylmercaptan to acrolein and hydrogen cyanide to 3-(methylthio)propanal.

The invention discloses a treatment method of cyanogens-containing organic waste gas. The waste gas is subjected to gas collection, is firstly treated by a cooler and a defoaming device, and then enters an acid washing tower to be subjected to acid washing and spraying so that ammonia gas and partial organic matters in the waste gas can be removed; then, the waste gas enters an alkaline washing tower and is sprayed by alkaline liquid; hydrogen cyanide and alkaline liquid take a reaction to produce a sodium cyanide water solution; partial water-soluble organic matters are absorbed by the alkaline liquid; the low-concentration organic waste gas discharged from the alkaline washing tower enters a catalytic oxidization tower, is absorbed by spraying liquid containing oxidizing agents of chlorine dioxide sprayed from the tower top, and then takes an oxygenolysis reaction through a catalyst bed layer; the rest waste gas is exhausted in a standard reaching way after finally passing an active carbon absorption tower. In the treatment process, no waste water or only a small amount of waste water is generated; the HCN in the waste gas is oxidized into harmless nontoxic and harmless N2 and CO2; the HCN removal rate can reach 99 percent or higher, so that the cyanide in the waste liquid is discharged in a standard reaching manner; the whole waste gas treatment process is simple; the treatment effect is good.

The invention relates to an apparatus and method for measuring the content of cyanide, the said apparatus comprises front treating apparatus and color measuring apparatus, wherein front treating apparatus includes peristaltic pump, automatic sampling device and online heating module which are connected with peristaltic pump; the said online heating module connects with online distilling module and six relaxing valve of coloring and measuring apparatus, wherein online distilling module is connected with sodium hydroxide absorbing liquid container linked with peristaltic pump; the said three relaxing pipe is connected with pipe with distilling regent solution. The method includes preparing miscellaneous needed solution and color measuring in the medium of pH3-4; distilling cyanides as hydrogen cyanides by online distilling; separating other disturbance by gas permeable membrane; inputting regent solution into hydrogen cyanic acid; doing colorimetric measuring by optical fiber spectrometer at wavelength of 580nm.

The object of the present invention is to obtain a highly soluble and colorless acrylamide polymer having a high molecular weight. A method for producing such acrylamide polymer involves comprises steps of: hydrating acrylonitrile containing oxazole at a concentration of 5 mg/kg or less and hydrogen cyanide at a concentration of 1 mg/kg or less by an enzymatic method to yield acrylamide; andt polymerizing monomers containing acrylamide.

The invention provides a method for testing content of hydrogen cyanide in gas. The method comprises the following steps of: absorbing the hydrogen cyanide in the gas by adopting a potassium hydroxide solution, transferring the absorption solution to a volumetric flask with a certain volume, taking a certain amount of absorption solution, adding a cadmium acetate solution to make sulfide in the absorption solution to form indissolvable cadmium sulfide to sediment, filtering and sintering the absorption solution to eliminate the sediments, taking Dabr as an indicator of the solution, taking a standard silver nitrate solution to titrate, making cyanide ions react with silver nitrateto form soluble cyanide complex ion (Ag(CN)2), making excessive silver ions react with the Dabar indicator so as to make the color of the solution change from yellow to orange to the end, and calculating the content of the hydrogen cyanide according to the volume of the consumed standard silver nitrate solution. The method provided by the invention solves the problems that various kinds of reagents used in the prior art are poisonous and harmful, and moreover the reagents have the disadvantages of complex analysis step, long elapsed time and the like, have potential safety hazards existing in the testing process, and enhance the sewage treatment load of the back section. The method can rapidly and accurately test the content of the hydrogen cyanide in coke oven coal.

A process for preparation of catalysts for the production of acrylonitrile, acetonitrile and hydrogen cyanide comprising contacting at an elevated temperature, propylene, ammonia and oxygen in the vapor phase in the presence of a catalyst, said catalyst comprising a complex of metal oxides wherein a heat-decomposable nitrogen containing compound is added during the process for the preparation of the catalyst.

A method for efficiently producing a cyanogen halide with suppressed side effects, and a method for producing a high-purity cyanate ester compound at a high yield includes contacting a halogen molecule with an aqueous solution containing hydrogen cyanide and/or a metal cyanide, so that the hydrogen cyanide and/or the metal cyanide is allowed to react with the halogen molecule in the reaction solution to obtain the cyanogen halide, wherein more than 1 mole of the hydrogen cyanide or the metal cyanide is used based on 1 mole of the halogen molecule, and when an amount of substance of an unreacted hydrogen cyanide or an unreacted metal cyanide is defined as mole (A) and an amount of substance of the generated cyanogen halide is defined as mole (B), the reaction is terminated in a state in which (A):(A)+(B) is between 0.00009:1 and 0.2:1.

A process and novel catalyst for the production of acrylonitrile, acetonitrile and hydrogen cyanide characterized by the relative yields of acrylonitrile, acetonitrile and hydrogen cyanide produced in the process and by the catalyst, which are defined by the following: a = [(%AN + (3 * %HCN) + (1.5 * %ACN)) %PC] * 100 wherein: %AN is the Acrylonitrile Yield and %AN = 81, %HCN is the Hydrogen Cyanide Yield, %ACN is the Acetonitrile Yield, %PC is the Propylene Conversion, and a is greater than 100.

The invention relates to a Chinese herbal additive for reducing hydrogen cyanide in main stream smoke of cigarette, and a preparation method and application of the Chinese herbal additive. The Chinese herbal additive comprises Endoconcha Sepiae, limonite, and smoked plum, wherein the weight ratio of limonite to Endoconcha Sepiae is (1 to 10):100, and the weight ratio of smoked plum to Endoconcha Sepiae is (1 to 6):100. The preparation method comprises: (1) preparing the mixture powder of limonite and Endoconcha Sepiae; (2) preparing smoked plum extract; (3) preparing additive powder; and (4) preparing the Chinese herbal additive. The Chinese herbal additive provided by the invention can remove hydrogen cyanide in smoke, and Endoconcha Sepiae has strong alkalinity, high activity, large adsorption area and high adsorption effect, and has effects in neutralizing and occluding hydrogen cyanide.

The invention provides a coal gas sampling method for determining the content of hydrogen cyanide in coal gas. The coal gas sampling method includes steps of leading coal gas to pass through cadmium acetate liquor so as to absorb hydrogen sulfide in the coal gas; then leading the coal gas to pass through potassium hydroxide liquor twice respectively to absorb the hydrogen cyanide in the coal gas so as to obtain sample absorption liquid absorbed with the hydrogen cyanide; leading the coal gas to pass through sulfuric acid liquor to absorb ammonia in the coal gas so as to protect a flow meter; and finally, leading the coal gas to pass through saturated picric acid liquor to absorb naphthalene in the coal gas and leading the coal gas to pass through the flow meter to obtain coal gas sampling quantity. After the sample absorption liquid absorbed with the hydrogen cyanide is inspected, the content of the hydrogen cyanide in the coal gas is obtained by means of conventional calculation. The coal gas sampling method effectively resolves the problem that as the content of sulfion in absorption liquid for determining the content of the hydrogen cyanide in the prior art is high, the content of the hydrogen cyanide in coal gas cannot be determined by a silver nitrate titration method. In addition, the coal gas sampling method is simple and practicable, and is easy in implementation.

The invention discloses a preparation method and an application of a hydrolyzed hydrogen cyanide catalyst and belongs to the technical field of catalysts and preparation of the catalyst. The preparation method comprises the following steps: dissolving inorganic salt of Cu, Zn and Al in distilled water and dissolving NaOH and Na2CO3 in distilled water to prepare a solution B; then dropwise adding a solution A and the solution B at a rate of 1-2 drop/s into a three-mouth flask at the same time, and fiercely stirring, after adjusting the pH of the mixed liquid to 9-10, crystallizing and filtering and washing the filter residues by using distilled water till the washing liquid is neutral, and drying to obtain Cu-Zn-Al hydrotalcite as a precursor; and putting the Cu-Zn-Al hydrotalcite as the precursor into a muffle furnace, carrying out temperature programming to reach 300-500 DEG C from 30-50 DEG C and roasting for 3-5 hours at 300-500 DEG C to obtain the Cu-Zn-Al compound oxide hydrolyzed hydrogen cyanide catalyst. The catalyst prepared by the method disclosed by the invention has the advantages of strong selectivity, high catalytic activity, strong hydrothermal stability, simplicity and convenience in regeneration and the like and has good application value and prospect.

The invention belongs to the technical field of cigarette production and particularly relates to an adsorbent for reducing the release amount of HCN (hydrogen cyanide) in mainstream smoke of a cigarette. The adsorbent belongs to a molecular sieve-polyether sulfone composite material, and the specific preparation steps include microporous-mesoporous molecular sieve SBA-15 preparation, molecular sieve modification, spinning and the like. The molecular sieve-polyether sulfone composite material provided by the invention has a loose and porous surface and contains a large amount of microporous, mesoporous and macroporous channel structures, thereby being favorable for improving the adsorption activity sites and the transmission efficiency of adsorbed substances; the prepared composite material better utilizes the weak acidity of the HCN and the complexing action of -CN groups and is used in a cigarette filter tip to prepare a composite filter tip, and 20 mg of the composite material is added into each cigarette filter tip, so that the release amount of the HCN in the mainstream smoke of the cigarette can be reduced by 1/4 to 1/3, and the adsorbent has relatively good promotion and application values.

The invention discloses a method for preparing isophorone diamine, and is characterized in that the method comprises the following steps: 1) under the condition of an organic amine catalyst, with isophorone and nitromethane as raw materials, synthesizing 3-nitromethyl-3,5,5-trimethylcyclohexanone, wherein the reaction temperature is 0 DEG C-150 DEG C, and the amount of the organic amine catalyst is 1-300% of the mass of the substance amount of isophorone; and 2) under conditions of liquid ammonia, hydrogen and a metal cobalt catalyst, allowing 3-nitromethyl-3,5,5-trimethylcyclohexanone to undergo a reaction to generate isophorone diamine, wherein the reaction temperature is 30-300 DEG C, the liquid ammonia amount is 1-50 times of the substance amount of 3-nitromethyl-3,5,5-trimethylcyclohexanone, and the hydrogen pressure is 0.1-10 MPa. The nitromethane with lower toxicity is used for replacing highly-toxic hydrogen cyanide or thiocyanate, and thus the method is a technical route which is safer in process and friendlier to the environment.

The invention provides additives for reducing hydrogen cyanide in cigarette smoke and a preparation method and application thereof and belongs to the technical field of tobacco products in the light industry. The additives include cuttlefish bone, salviae miltiorrhizae, paeonia suffruticosa, fritillary bulb, platycodon grandiflorum and rhubarb, wherein the weight ratio between the salviae miltiorrhizae and the cuttlefish bone is 1-8:100, the weight ratio between the paeonia suffruticosa and the cuttlefish bone is 1-5:100, the weight ratio between the fritillary bulb and the cuttlefish bone is 1-5:100, the weight ratio between the platycodon grandiflorum and the cuttlefish bone is 1-6:100, and the weight ratio between the rhubarb and the cuttlefish bone is 1-6:100. The additives can selectively and effectively reduce the release amount of the harmful ingredient hydrogen cyanide in the cigarette main stream smoke, reduce stimulation and injury of the smoke on the cardiovascular system of a human body, improve safety performance of tobacco smoking and give tobacco a specific medicine aroma style characteristic.