423 results about "Hydrogen cyanide" patented technology

An electric smoking system includes a cigarette including a cylindrical tobacco web partially filled with tobacco material to define a filled tobacco rod portion and an unfilled tobacco rod portion, and an electric lighter. The wrapper includes a filler of ammonium-containing compounds effective to reduce the gaseous constituents of the smoke produced during smoking. The system includes a pilot burner including at least one heating vane and a controller adapted to control heating of the heating vane. The lighter is configured to at least partially contain the cigarette such that the heater blade heats the heating region of the cigarette. Manipulating the controller to limit the heating of the heater blades to a predetermined temperature range which allows the delivery of the smoke generated when the portion of the tobacco rod is heated while at least reducing the amount of smoke present in the smoke as compared to smoking a cigarette having only calcium carbonate as filler. A gaseous component. The gaseous components that can be reduced include carbon monoxide, 1,3 butadiene, isoprene, acrolein, acrylonitrile, hydrogen cyanide, 0-toluidine, 2-naphthylamine, nitrogen oxide, benzene, NNN, Phenol, catechol, benzanthracene and benzopyrene.

Decontamination formulations for neutralization of toxic industrial chemicals, and methods of making and using same. The formulations are effective for neutralizing malathion, hydrogen cyanide, sodium cyanide, butyl isocyanate, carbon disulfide, phosgene gas, capsaicin in commercial pepper spray, chlorine gas, anhydrous ammonia gas; and may be effective at neutralizing hydrogen sulfide, sulfur dioxide, formaldehyde, ethylene oxide, methyl bromide, boron trichloride, fluorine, tetraethyl pyrophosphate, phosphorous trichloride, arsine, and tungsten hexafluoride.

The invention discloses a grapheme type fiber cigarette filter and a preparation method thereof. The filter comprises a fiber carrier, wherein the fiber carrier is provided with a grapheme type material for absorbing harmful components in smoke. The filter loads the grapheme type material on a carbon fiber or acetate fiber carrier; and the carrier is added in the filter by adopting the binary filter production mode in the existing industries to produce a compound filter for absorbing harmful substances in the smoke which is generated when cigarettes are smoked. The filter applies unique phi absorption characteristics and higher surface active atom ratio of novel two-dimensional nanometer materials to efficiently absorb benzo [a] pyrene, volatile aldehyde ketone type cancer promoting molecules, phenol and HCN (Hydrogen Cyanide) under the condition of smaller adding quantity, so that the filter is environment-friendly and has no additional poison; as the amount is small and the effect is high, the harm of the cigarettes to human bodies is reduced under the condition of not influencing the inherent sensory quality of the cigarettes. And at the same time, the method has the advantages of simple technique, large-scale production and low cost, and has wide application foreground in the cigarette field of harm reduction and tar reduction.

The invention provides a method for producing liquefied natural gas by using coke oven gas. The method comprises the following steps: (1) the coke oven gas is pretreated to remove benzene, naphthalene, tar and HCN (hydrogen cyanide); (2) sulfur is removed; (3) carbon is removed and the coke oven gas is dried; (4) the coke oven gas is led to a first heat exchanger and pre-cooled; (5) the pre-cooled coke oven gas passes through a second heat exchanger, a reboiler at the bottom of a low-temperature rectifying tower and a third heat exchanger in sequence, so that the temperature is lowered step by step; (6) gaseous liquid coming out of the third heat exchanger is led to a gas-liquid separator for gas-liquid separation, then the liquid coming out of the gas-liquid separator enters the low-temperature rectifying tower, and a liquefied natural gas product is acquired at the bottom of the low-temperature rectifying tower; and otherwise, the gaseous liquid coming out of the third heat exchanger is directly led to the low-temperature rectifying tower, and the liquefied natural gas product is acquired at the bottom of the low-temperature rectifying tower. The method for producing the liquefied natural gas by using the coke oven gas as raw material has the advantages of high output as well as low energy consumption and cost, and is easy to operate.

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 nitriles having five carbon atoms, hydrogen cyanide, and a catalyst precursor composition, by continuously feeding ethylenically unsaturated nitriles, 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 nitriles, 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 multidentate phosphorus-containing ligand;
  • wherein the multidentate phosphorus-containing ligand is selected from the group consisting of a phosphite, a phosphonite, a phosphinite, a phosphine, and a mixed phosphorus-containing ligand or a combination of such members; and
  • wherein the multidentate phosphorus-containing ligand gives acceptable results according to at least one protocol of the 2-Pentenenitrile Hydrocyanation Test Method.

A method for the production of 2-hydroxy-4-(methylthio)butyronitrile having good storage stability in a multi-zone reactor, is provided. 3-methylmercaptopropionaldehyde is reacted with hydrogen cyanide in the presence of a base as catalyst in a main reaction zone of the multizone reactor to form a reaction mixture comprising the 2-hydroxy-4-(methylthio)butyronitrile, unreacted 3-methylmercaptopropionaldehyde, the catalyst and residual amounts of gaseous hydrogen cyanide. The residual gaseous hydrogen cyanide is removed from the main reaction zone to an absorption and post-reaction zone of the reactor which comprises a mixture of 3-methylmercaptopropionaldehyde and the catalyst; and the gaseous hydrogen cyanide is further reacted with the 3-methylmercaptopropionaldehyde in the absorption and post reaction zone. A molar ratio of hydrogen cyanide to 3-(methylthio)propanal in the main reaction zone is from 0.98 to 1.03.

The invention relates to a water retaining material, a preparation method thereof and an application of the water retaining material in a filter rod. The invention is characterized in that water-retaining substances and alkaline components are introduced into a porous material with larger specific surface area simultaneously, and the water-retaining material for selectively reducing hydrogen cyanide (HCN) in mainstream cigarette smoke is obtained. The material has certain content of water due to water-retaining substances in the material, simultaneously the alkaline components can generate acid-alkaline reaction with the hydrophilic HCN in the mainstream cigarette smoke, and the selective harm reduction performance of the material to the HCN in the mainstream cigarette smoke is further enhanced. 10-40mg of the material is added in per piece of the filter rod of the cigarette, therefore, the release amount of the hydrogen cyanide in the mainstream cigarette smoke can be reduced by more than 30 percent, while the release amount of tar is basically not changed or reduced slightly, and simultaneously no bad influence is caused on the smoking quality of cigarettes, and the purpose of realizing selective harm reduction is further achieved.

The invention relates to the field of electrochemical sensors, and in particular relates to an HCN (hydrogen cyanide) four-electrode electrochemical sensor resistant to nitrogen monoxide and nitrogen dioxide interference. The HCN electrochemical sensor provided by the invention comprises a first working electrode, a second working electrode, a reference electrode and a counter electrode which form ion conduction via electrolyte, wherein the first working electrode is a carbon element electrode, and the second working electrode an Au-containing electrode. The HCN electrochemical sensor provided by the invention is capable of effectively eliminating the cross interference between NO and NO2 and accurately measuring the concentration of an HCN gas via the design of a four-electrode sensor system comprising the reference electrode, the counter electrode and the two working electrodes.

The invention discloses a preparation method of a modified bio-charcoal based catalyst, which can remove carbonyl sulfide, carbon disulfide, and hydrogen cyanide at the same time. The bio-charcoal is taken as the carrier, a series of modifications is carried out to prepare the catalyst, the catalyst is applied to catalytic hydrolysis so as to simultaneously remove COS, CS2, and HCN; the work temperature of the catalyst is not higher than 100 DEG C, the removal rates of COS and CS2 are not less than 90%, the removal rate of HCN is not less than 70%; and the bio-charcoal based catalyst is prepared by the following steps: subjecting waste biomass to carbonization and activation in sequence so as to obtain the bio-charcoal carrier, then boiling the bio-charcoal carrier in a KOH solution, adding the bio-charcoal carrier in a metal salt solution to carry out ultrasonic impregnation, then burning the bio-charcoal carrier at a certain temperature; adding the burned bio-charcoal carrier into an alkaline solution to carry out ultrasonic impregnation, and finally drying to obtain the bio-charcoal based catalyst. The technology is concise, the operation is convenient, the operation is continuous, COS, CS2 and HCN in flue gas are removed and converted into valuable resources, and no secondary pollution is generated.

The invention relates to a metal complexing material and a preparation method thereof, and application of the metal complexing material to cigarettes. The invention is characterized in that: the complexing material is obtained by complexing a porous carrier with large specific surface area, such as ion exchange resin, ion exchange fibers, macroporous adsorption resin and the like, and different metal ions, and is applied to the cigarettes in a form of a binary composite filter stick; 10 to 40mg of complexing material is added into each cigarette, so that hydrogen cyanide (HCN) in mainstream smoke can be selectively reduced by over 25 percent; meanwhile, the complexing material does not have negative effects on the sensory quality of the cigarettes. The porous carrier in the material has large specific surface area, so smoke can be effectively contacted with the functional group of the material when passing through the material; meanwhile, the metal ions on the surface can be subjectedto complexing reaction with the HCN, so that the HCN in the smoke of the cigarettes is selectively removed.

The invention relates to a method of the catalytic oxidation and purification of tail gas containing hydrocyanic acid, in particular to a method for purifying the tail gas containing hydrocyanic acid by using a chemical method. The tail gas containing hydrocyanic acid is enabled to react with a prepared mixed catalyst solution containing palladium and copper under the temperature of 4 to 100 DEG C in a absorption tower, and the tail gas containing hydrocyanic acid is blown into the absorption tower in a gas-liquid negative-direction contact way, part of the hydrocyanic acid contacts and reacts with the palladium ions to form insoluble palladium simple substance, and part of the hydrocyanic acid reacts with the copper ions to form insoluble phosphor copper, part of the hydrocyanic acid is oxidized into phosphoric acid; all the generated substances enter into the liquid phase, and the mixed catalyst solution which absorbs the hydrocyanic acid and the purified and qualified tail gas not containing the hydrocyanic acid are acquired, the mixed hydrocyanic acid catalyst solution is oxidized into a by-product of the phosphoric acid to be used as resources again, the problems of hydrocyanic acid pollution is effectively eliminated, and the method provided by the invention provides a practical purifying method for the calcium carbide furnace gas and yellow phosphorus exhaust gas used as monocarbide chemical raw materials.

The invention discloses a modified natural plant filter tip additive material capable of selectively reducing burst size of hydrogen cyanide in main stream smoke of cigarettes and a preparation method of the modified natural plant filter tip additive material. The modified natural plant filter tip additive material takes the natural plant material as a carrier and is prepared through carboxylation and loading of transition metal ions sequentially. According to the invention, the filter tip additive material prepared by taking the natural plant material as the carrier has the porous adsorption property and is rich in transition metal ions; as CN- has strong complexation to the transition metal ions, the filter tip additive material can perform effective adsorption and complexation on hydrogen cyanide, and the purpose of selectively reducing burst size of hydrogen cyanide in main stream smoke of cigarettes is realized. According to the modified natural plant filter tip additive material and the preparation method, the source of the raw material is extensive, green and environmentally friendly; the prepared filter tip additive material is high in safety, simple in preparation technology, low in cost, and easy to produce on a large scale; when applied to cigarette filter tips, the modified natural plant filter tip additive material can selectively reduce burst size of hydrogen cyanide in main stream smoke of cigarettes by more than 35% with no negative effect on the sensory quality of cigarettes.

The invention relates to an environmental-friendly new method for preparing N-phosphonomethyl iminodiacetic acid by utilizing acrylonitrile byproduct hydrocyanic acid, belonging to the comprehensive utilization of acrylonitrile device byproduct hydrocyanic acid in industrial scale. The method includes that: step first, acrylonitrile byproduct hydrocyanic acid is used for preparing hydroxyl acetonitrile, and then iminodiacetonitrile is prepared; step two, the obtained iminodiacetonitrile is used for preparing iminodiacetic acid by acid hydrolysis method; and step three, the obtained iminodiacetic acid is used for preparing N-phosphonomethyl iminodiacetic acid. No report of preparing PMIDA by utilizing acrylonitrile byproduct hydrocyanic acid in industrial scale is seen, and the inventor uses local materials, utilizes the advantages of being adjacent to Qilu petrochemical and having resource of hydrocyanic acid (4000 ton/year) transmitted by pipeline and initially provides the method for preparing PMIDA by utilizing acrylonitrile byproduct hydrocyanic acid in industrial scale. The invention solves the problem of region restriction of product production caused by inconvenient transportation of hydrocyanic acid. A gas and liquor mixer is applied to iminodiacetonitrile reaction, and by virtue of DCS control system, quality and yield of iminodiacetonitrile are improved.

A process for the production of sodium cyanide crystals comprising;

• • (a) contacting impure hydrogen cyanide and sodium hydroxide in a reactor with mixing for a maximum contact time of about 5 seconds;
  • (b) feeding the resulting mixture to a continuous evaporative crystallizer to produce a slurry of sodium cyanide crystals;
  • (c) passing the slurry of sodium cyanide crystals from the crystallizer over a hot surface to precipitate onto the surface and remove sodium carbonate, and passing said slurry back to the crystallizer; and
  • (d) separating the sodium cyanide crystals from the slurry.

The invention provides a test method, which includes the following steps: distilling soil in pH<2 acidic medium, hydrogen cyanide is formed, absorbing with the sodium hydrate solution, and analyzing total cyanide in soil with isonicotinic acid-barbituric acid spectrophotometry. The invention has the advantages of good sensitivity and good repeatability, which provides a convenient and reliable method for analyzing total cyanide in soil, and meets the needs of soil pollutant analysis as well as research work.

The invention concerns a hydrocyanation method for ethylenically unsaturated organic compounds in particular to obtain nitriles, and more particularly hydrocyanation of substituted diolefins or of olefins for producing dinitriles, and/or the isomerization of nitriles obtained by hydrocyanation. The invention more particularly concerns hydrocyanation catalysed by a nickel-based compound. Thus the catalyst used in said production method is treated in output with hydrogen cyanide to recover and re-dissolve the nickel precipitated in the form of nickel hydroxide. The method enables to regenerate and prolong the life span of a catalyst charge. Moreover, it enables to reduce pollution in the installations using said method.

This invention concerns a treatment method for the organic wastewater containing hydroxyacetonitrile, phenylaminoacetonitrile, aniline, diazo value, etc. nitrile-bearing refractory organism. Said method comprises carrying out microelectrolysis under acidic condition, and then adding ferrous sulfate for redox reaction and flocculation process. The mechanism is to make nitriles and CN-NH3-N into small molecules or produce insoluble precipitate through synergetic effect of a series reactions like electrolysis, redox and aeration oxidation, and further decomposition, oxidation and reduction, and remove them through flocculation. The nitriles and hydrogen cyanide like hydroxyacetonitrile and phenylaminoacetonitrile in the water can be removed completely. Aniline can be degraded and removed. CODcr removal percentage is 35-45%.

The invention discloses a measuring method for cyanides in cyanide-containing wastewater of a gold mine. In order to solve the problem that a great number of foams are produced by heating and distilling under an acidic condition, a defoaming agent GC-1 is added into a cyanide-containing wastewater sample to inhibit activities of a surfactant in wastewater, so that the water sample does not produce foams in a distilling process; phosphoric acid and Na2-EDTA are added into the water sample, and heated and distilled in a medium with pH lower than 2, so that cyanide ions are separated from complex cyanide by utilizing the characteristic that the complexing capacity between the metal ions and the EDTA is higher than that between the metal ions and the cyanide ions, the cyanide ions are distilled in the form of hydrogen cyanide, and the content of the cyanide ions is titrated by silver nitrate after the cyanide ions are absorbed by a sodium hydroxide solution. Under an alkaline condition, the cyanide ions act with the silver nitrate to form soluble sliver-cyanogen complex irons (Ag(CN)2<->), and the excessive sliver ions react with 5-(4-dimethylaminobenzylidene)rhodanine indicator liquor, so that the solution is changed into orange red from yellow, thereby ending the measurement. The method has the advantages of obvious effect and accurate measured result, and is simple to operate and easy to grasp.

Processes are disclosed for the anaerobic bioconversion of syngas to oxygenated organic compound that use an in situ method for protecting the microorganisms from hydrogen cyanide contained in the syngas that passes to the fermentation broth. The fermentation broth is maintained at a pH of between about 4 and 6, and dissolved metal cation of one or more of iron, cobalt, nickel and zinc is provided to the fermentation broth in an amount sufficient to form, under the conditions of the fermentation broth, a substantially insoluble metal complex with the metal cation and cyanide anion. The rate of formation of the insoluble complex is sufficiently high that that the amount of cyanide that is taken up by microorganisms does not result in an undue adverse effect on the population of microorganisms.

A process is provided for producing glycolic acid from formaldehyde and hydrogen cyanide. More specifically, heat-treated formaldehyde and hydrogen cyanide are reacted to produce glycolonitrile having low concentrations of impurities. The glycolonitrile is subsequently converted to an aqueous solution of ammonium glycolate using an enzyme catalyst having nitrilase activity derived from Acidovorax facilis 72W (ATCC 57746). Glycolic acid is recovered in the form of the acid or salt from the aqueous ammonium glycolate solution using a variety of methods described herein.

The invention relates to a novel preparation of a green chelating agent glutamic diacetate tetracetic acid metal salt. The preparation comprises the steps of synthesizing GLDA-4Na tetrasodium glutamate diacetate (GLDA-4M) through L-glutamic acid, 2-chloroacetonitrile organic alkali, zinc chloride and sodium hydroxide; carrying out cyanation and hydrolysis of L-glutamic acid to obtain the aqueous solution of the GLDA-4Na; and then carrying out decolorizing and concentrating to obtain the product. According to the preparation, the 2-chloroacetonitrile organic alkali is adopted to replace the common HCN (hydrogen cyanide) in the prior art, so that the use of the extremely toxic substance is reduced, and the produced wastewater can be easily processed; and green chelating agent glutamic diacetate tetracetic acid metal salt has high yield, high purity, and low cost, and is simple in technology, and easy to realize post-treatment to the wastewater, and achieve industrial production.

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:

α=[(% 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
  • α is greater than 100.