69 results about "HCN poisoning" patented technology

A process for operating an oxidizable combustion gas cleaning unit in a metallurgical plant, including the steps of: (a) passing an oxidizable combustion gas from a metallurgical reactor, in particular a blast furnace gas from a blast furnace, in a packed bed scrubber arrangement through a packed bed in countercurrent with a washing water or in a spray scrubber arrangement to remove cyanide compounds, in particular hydrogen cyanide, and to increase the removal of chloride compounds, in particular hydrogen chloride, from the combustion gas by solubilizing the cyanide and chloride compounds in the washing water, (b) collecting the washing water containing solubilized cyanide and chloride compounds at a bottom end of the packed bed or spray scrubber arrangement, and (c) collecting a cleaned oxidizable combustion gas at a top of the packed bed or spray scrubber arrangement, wherein a base is added to the washing water before step (a).

The invention relates to a method for exhaust-gas treatment, comprising the steps of: (a) generating an exhaust gas comprising HCN, NOX and N2O, the HCN content being at least 1.0 ppmv; (b) optionally feeding a reducing agent for NOX and / or for N2O into the exhaust gas; and (c) reducing the HCN content in the exhaust gas by catalytically reacting the HCN on a transition-metal-loaded zeolitic material.

The utility model belongs to the technical field of coke oven gas desulfurization and decyanation, and particularly relates to a vacuum potassium carbonate multi-stage desulfurization and decyanation device which is characterized in that a tower body of a multi-stage single tower structure sequentially comprises a potassium carbonate washing section, a potassium hydroxide washing section, a sodium hydroxide washing section and an alkali mist removal section from bottom to top, a distributor I is arranged between the potassium carbonate washing section and the potassium hydroxide washing section and is connected with a desulfurization barren solution inlet, and an outlet I of a liquid breaking disc I is connected with a potassium hydroxide tank; a distributor II is arranged between the potassium hydroxide washing section and the sodium hydroxide washing section, a liquid breaking disc II is arranged above the distributor II, and a circulating pump is arranged on the pipeline; a distributor III is arranged between the sodium hydroxide washing section and the alkali mist removal section; and an outlet II of the liquid breaking disc I is communicated with the tower body below the distributor I through a short circuit pipe. The technical scheme has the advantages that the desulfurization and decyanation efficiency is improved, hydrogen sulfide and hydrogen cyanide can be efficiently absorbed by combining multiple washing modes, and the removal efficiency is improved.

The present invention relates to a hydroxyacetonitrile production method and production system based on a carbon fiber off-gas. The carbon fiber off-gas comprises a carbonization off-gas. The hydroxyacetonitrile production method comprises the following steps: subjecting the carbonization off-gas to de-tarring treatment and de-ammoniation treatment to obtain a treated off-gas; and performing a nucleophilic addition reaction between the treated off-gas and formaldehyde in the presence of a catalyst to obtain the hydroxyacetonitrile. By subjecting the carbonization off-gas to de-tarring treatment and de-ammoniation treatment and performing a nucleophilic addition reaction between the treated off-gas and formaldehyde in the presence of the catalyst to obtain the hydroxyacetonitrile, the present invention can significantly reduce the contents of hydrogen cyanide and ammonia gas in the off-gas, and the treated off-gas can meet emission standards. In addition, using the carbon fiber off-gas as a starting material to produce hydroxyacetonitrile can also be achieved, thereby leading to improved resource utilization rate and economic benefits.

The utility model relates to an air inlet distributor structure for a hydrocyanic acid fluidized bed reactor. The air inlet distributor structure comprises a plate-type distributor arranged at the bottom of the fluidized bed reactor, the conical sealing head is connected with the bottom of the fluidized bed reactor and defines an air pressure equalizing chamber; the air inlet pipe extends into the air pressure equalizing chamber from the side, an outlet of the air inlet pipe faces upwards, a guide plate with a conical umbrella surface is further arranged above the outlet end of the air inlet pipe, and a horizontal radial air guide port is formed between the bottom end of the guide plate and the outlet of the air inlet pipe. Compared with the prior art, the utility model can solve the problems of abrasion caused by direct washing of the plate-type distributor due to overlarge air flow in the air inlet pipe, poor catalyst accumulation or excessive abrasion caused by uneven air flow distribution and the like.

A process for the hydrocyanation of an organic compound containing at least one olefinic group comprising reacting the organic compound with hydrogen cyanide in the presence of a catalyst complex comprising at least one transition metal and a phosphorus-containing ligand comprising a calixarene backbone and at least two aryl phosphite or aryl phosphoramidite groups chemically bonded to the backbone.

The present invention provides a method for removing hydrogen sulfide (H2S) and hydrogen cyanide (HCN) from concentrated ammonia water, the method comprising: a catalyst treatment step of contacting concentrated ammonia water containing hydrogen sulfide (H2S) and hydrogen cyanide (HCN) with an iron oxide catalyst; and a regeneration step of supplying a regeneration solution to the iron oxide catalyst to regenerate the iron oxide catalyst. According to the present invention, by simultaneously removing hydrogen sulfide (H2S) and hydrogen cyanide (HCN) contained in concentrated ammonia water, it is possible to improve the absorption efficiency of hydrogen sulfide (H2S) and hydrogen cyanide (HCN) of coke oven gas (COG) when using concentrated ammonia water in an H2S scrubber (H2S / S).

To improve a mature taste or premium richness in plum liqueur or a plum liqueur-containing beverage with a lower hydrogen cyanide content.SOLUTION: In plum liqueur with a lower hydrogen cyanide content or a beverage containing the same, a furfural content and / or an ethyl octanoate content are regulated within specific ranges.SELECTED DRAWING: None

The invention relates to catalytically active heating elements, and to the production and use thereof in the production of hydrogen cyanide (HCN). The problem addressed by the invention is that of providing thermally stable and catalytically active heating elements with which a BMA process can be simultaneously electrically heated and chemically catalysed. In particular, the heating elements should be thermally and mechanically stable in continuous industrial operation and retain their catalytic activity. The heating element according to the invention has a layered structure (A, B, C) formed from (A) silicon carbide (SiC), (B) aluminium nitride (AlN) and (C) platinum (Pt). The silicon carbide (SiC) serves as an electric heating resistor. The platinum (Pt) serves as catalyst. Aluminium nitride (AIN) is arranged as a protective layer between platinum (Pt) and silicon carbide (SiC). It prevents platinum (Pt) and silicon carbide (SiC) from alloying during ongoing operation.

The invention discloses a method for synthesizing hydrogen cyanide from a carbon-containing solid and ammonia gas, and belongs to the technical field of hydrogen cyanide production. The method comprises the following steps: contacting ammonia gas with a carbon-containing solid heated to a reaction temperature, and carrying out a gas-solid reaction to generate a high-temperature gas containing hydrogen cyanide; according to the invention, the technical route that the existing hydrogen cyanide production technology mainly depends on a gaseous hydrocarbon carbon source, a noble metal catalyst and external combustion heat supply is changed, and the problems of limited raw material sources, easiness in catalyst deactivation, slow process start-stop response and the like are solved.

The invention relates to a ship tail gas hydrogen cyanide (HCN) purification catalyst and a preparation method and application thereof. The preparation method comprises the following steps: calcining TiO2 powder to remove surface impurities and stabilize a crystal form; the preparation method comprises the following steps: respectively dissolving active components in oxalic acid / citric acid solutions, and fully stirring and mixing all component solutions; immersing the TiO2 carrier into a mixed solution containing an active component precursor, and stirring; performing rotary evaporation to remove free moisture, and drying; and roasting the dried precursor in a muffle furnace to obtain the HCN selective oxidation catalyst. According to the scheme provided by the invention, the interaction among the active components can be greatly improved, the thermal stability is high, the dispersity is high, the agglomeration of the active components can be effectively reduced, and the performance is excellent. Meanwhile, the catalyst is high in selectivity, generation of greenhouse gas N2O can be reduced, no additional treatment device needs to be added, and the use cost is reduced.

The utility model relates to the field of fluidized bed reactor structural members, in particular to an air distribution plate structure for a hydrocyanic acid fluidized bed reactor, which comprises a distribution plate main body, the plurality of air distribution pipes are distributed in an array manner, are vertically fixed on the distribution plate main body and are used for introducing air; the plurality of flow guide caps are fixed on the distribution plate main body and are arranged above the tops of the air distribution pipes in a one-to-one correspondence manner, a horizontally through air guide cavity with openings at two ends is formed between the flow guide caps and the distribution plate main body, and any two adjacent flow guide caps are arranged in a 90-degree staggered manner; and therefore, horizontal airflow sprayed from one flow guide cap can be directly blown to the side surface of the adjacent flow guide cap. Compared with the prior art, uniform fluidization of the whole catalyst bed layer can be effectively guaranteed, the problem that a traditional distribution plate is prone to material accumulation is thoroughly solved, the phenomena of local overheating and channeling are avoided, and the gas-solid contact efficiency is improved.

The invention relates to the technical field of chemical production, and specifically discloses a component pretreatment method for hydrogen cyanide synthesis gas. The method comprises the following steps: step S1: introducing a diammonium phosphate solution into an ammonia removal device and starting the ammonia removal device; step S2: introducing hydrogen cyanide synthesis gas containing ammonia into the ammonia removal device, causing the ammonia to react with the diammonium phosphate solution to generate diammonium phosphate, which is retained in the ammonia removal device, and the hydrogen cyanide synthesis gas to be directly discharged from the ammonia removal device; and step S3: thermally decomposing the retained diammonium phosphate solution in the ammonia removal device to generate ammonia and a diammonium phosphate solution, discharging the ammonia separately, and refluxing the diammonium phosphate solution into the ammonia removal device to reabsorb the hydrogen cyanide synthesis gas containing ammonia. The method solves the problem in a traditional hydrogen cyanide preparation process that, during absorption treatment of ammonia in the hydrogen cyanide synthesis gas, complexes generated are accumulated at the bottom of an ammonia absorption tower, and the complexes entrained in the solution discharge process affect the discharge of liquid and the discharge of ammonia from the solution.

The invention discloses a hydrogen cyanide waste gas treatment method based on intelligent wearable equipment and electronic equipment, and relates to the technical field of harmful gas treatment.The hydrogen cyanide waste gas treatment method comprises the steps that inertia measurement data, position vector data and visual auxiliary data are obtained through the intelligent wearable equipment; determining an initial position vector according to the inertial measurement data, the position vector data and the visual auxiliary data; performing state prediction and observation updating according to the initial position vector to obtain an optimized position vector, and determining a waste gas treatment area according to the optimized position vector; and obtaining the hydrogen cyanide concentration through the intelligent wearable device, and executing waste gas treatment operation corresponding to a preset concentration interval in the waste gas treatment area according to the preset concentration interval of the hydrogen cyanide concentration. The waste gas treatment area can be determined according to the position of the operator, accurate waste gas emission is achieved, the accuracy of hydrogen cyanide detection based on the position of the operator is improved, and hydrogen cyanide waste gas treatment in the waste gas treatment area is achieved.

The goal is to artificially ripen unripe green plums in a short period of time, thereby providing plums that are equivalent in quality to naturally ripened, fully mature plums. [Solution] In the decomposition step S4, the decomposition of cyanogenic glycosides such as amygdalin contained in the pulp of raw plums promotes the production of hydrogen cyanide and benzaldehyde. In the detoxification step S5, the produced hydrogen cyanide and benzaldehyde are detoxified. In the high-temperature sterilization step S7, the detoxified plums are sterilized at high temperature. In the ultraviolet irradiation step S8, the plums are further ripened by ultraviolet irradiation. As a result, unripe green plums can be artificially ripened in a short period of time, such as a few days, and plums equivalent to naturally ripened yellow plums that mature over about a month can be obtained.

The present application relates to a kind of processing method of waste containing hydrogen cyanide and ammonia, it includes: the wastewater containing hydrogen cyanide and ammonia and the waste gas containing hydrogen cyanide and ammonia are introduced into absorption tank respectively, and hydrogen peroxide solution is added to the absorption tank, adjust pH to obtain the liquid with pH value of 6 to 11;The liquid is transported to oxidation reactor, the reaction temperature of the oxidation reactor is controlled at 40 to 60 ℃, and the total residence time of the liquid in the oxidation reactor is 150 to 270 minutes, to oxidize hydrogen cyanide into ammonia and carbon dioxide;Ammonia in the liquid is removed by gas stripping method.The method can safely and efficiently reduce hydrogen cyanide and ammonia in waste gas and wastewater, efficiently and significantly oxidize hydrogen cyanide into carbon dioxide and ammonia without or with low by-product, without using heavy metal catalyst.

The application provides a hydrogen cyanide synthesis gas ammonia removal and purification device, wherein an ammonia removal circulating assembly is arranged between an ammonia removal tower and a first liquid collecting pack, the top of the ammonia removal tower is provided with the first liquid collecting pack, a flow limiting orifice plate is arranged between the first liquid outlet of the first liquid collecting pack and the middle liquid inlet of the ammonia removal tower, an absorption circulating assembly is arranged between the bottom of an absorption tower and the middle of the absorption tower, the top of the absorption tower is provided with a second liquid collecting pack, a flow limiting orifice plate is arranged between the second liquid collecting pack and the middle of the absorption tower, and the distillation tower kettle discharge port is communicated with the second liquid collecting pack inlet and the liquid phase inlet at the upper end of the ammonia removal tower through pipelines. The hydrogen cyanide synthesis gas ammonia removal and purification device optimizes the process flow and the equipment structure, improves the ammonia absorption rate and the hydrogen cyanide recovery rate, simultaneously provides emergency treatment measures for abnormal working conditions in production, and provides a guarantee for the safe and stable operation of the hydrogen cyanide production device.

A hydrodesulfurization, deoxidation and hydrogen cyanide removal multifunctional purification catalyst applicable to ultra-low emission and comprehensive use of industrial tail gas, and the use thereof. Said catalyst uses activated carbon as a support, and is loaded with copper sulfate and titanium sulfate, the mass percentage of copper sulfate relative to the mass of the support being 5-15%, and the mass percentage of titanium sulfate relative to the mass of the support being 3-12%. Said catalyst is applicable to multifunctional purification of COS, CS2 and SO2 in low-hydrogen high-oxygen industrial tail gas such as blast furnace gas, carbon black tail gas and calcium carbide tail gas via hydrogenation conversion, deoxidization and hydrogen cyanide removal, solves the problem that traditional alumina-based cobalt-molybdenum, nickel-molybdenum or iron-molybdenum catalysts are prone to deactivation and have poor hydrogenation activity in said atmospheres, and exhibits low side reactions of carbon monoxide shift, thus facilitating source treatment and ultra-low emission of the described industrial tail gas while facilitating comprehensive use of subsequently recovered CO and hydrogen.

The utility model belongs to the technical field of industrial safety control, and particularly relates to a protection system for detecting indoor hydrogen cyanide leakage. Comprising a closed detection chamber, an online analysis instrument, a poison gas sensor and a smoke sensor are arranged in the closed detection chamber, a closed door is arranged on the side wall of the closed detection chamber, a door lock controller and an audible and visual alarm are arranged above the closed door, an exhaust port is formed in the top of the closed detection chamber, and the exhaust port is connected with an exhaust fan through a pipeline. And an outlet of the exhaust fan is connected with the waste incinerator. The system can monitor the leakage condition of toxic gas in real time, triggers sound-light alarm in the first time, effectively reminds surrounding operators to pay attention and rapidly evacuate, and greatly reduces the risk of personnel poisoning; meanwhile, intelligent control and automatic processing are achieved through the control system, the emergency response speed and processing efficiency are improved, and the risk and cost of manual intervention are reduced.

The invention relates to the technical field of solid waste treatment, and discloses a decyanation method and a decyanation system for effectively reducing the content of hydrocyanic acid. The decyanation method specifically comprises the following steps: in a decyanation tower, heating a solution through a reboiler, introducing hot nitrogen into a tower kettle to carry out synergistic steam stripping, and strongly analyzing dissolved HCN by utilizing a Henry law principle, so that the content of HCN in a discharged material of the tower kettle is reduced to be less than 1ppm; and meanwhile, the operating pressure at the top of the decyanation tower is controlled in a low-pressure range of 10-25kPa, so that the boiling point of the solution is obviously reduced, and the steam consumption of the reboiler is reduced by about 20%. The system is also integrated with a feed preheating energy recovery unit, a tower top condensate shunting rectification unit and a non-condensable gas safety treatment unit. The method has remarkable and synergistic beneficial effects in the aspects of decyanation efficiency, energy consumption control, safety, environmental protection and economic benefits, and comprehensively overcomes the bottlenecks in the prior art.

Provided in the present invention is a reactor for preparing hydrogen cyanide. The reactor comprises a reaction zone and a cooling zone, wherein a tapered tube plate is provided at the lower end of a shell in the reaction zone; an upper cooling shell in the cooling zone covers the periphery of a lower shell in the reaction zone; and a steam outlet is provided at the position on the upper cooling shell in the cooling zone that is staggered with the shell in the reaction zone. By using the above arrangement, a specific gas-liquid phase distribution is formed in the upper space in the cooling zone, ensuring that high-temperature elements (the tops of the tapered tube plate and a heat exchange tube) come into full contact with a coolant, and keeps away from a coolant high-temperature gas phase region as far as possible; and the stable operation of the device is facilitated.

The utility model relates to an air distribution plate and a hydrocyanic acid reactor comprising the same, and belongs to the technical field of chemical equipment. The air distribution plate comprises a horizontally mounted distribution plate main body, an air distribution pipe vertically embedded in the distribution plate main body, and an inner wall supporting structure for connecting the distribution plate main body and the inner wall of the reactor, and the supporting beam structure is used for supporting the bottom of the distribution plate main body. The supporting beam structure is specifically an H-shaped steel supporting beam or a polygonal structure supporting beam. Compared with the prior art, the air distribution plate disclosed by the utility model can be used for spraying air in the vertical direction and uniformly diffusing the air, so that the air is more fully mixed with feed gas, a catalyst is fully fluidized, and the product conversion rate and the reactor performance are improved.

The invention relates to the technical field of gold-loaded carbon desorption tail gas treatment, in particular to an ammonia-mercury cooperative treatment method and system for gold-loaded carbon desorption electrolysis pressure relief tail gas. The ammonia and mercury cooperative treatment method for the gold-loaded carbon desorption electrolysis pressure relief tail gas comprises the steps of first-stage condensation, second-stage absorption, third-stage spraying and fourth-stage adsorption of high-temperature steam, and ammonia and mercury in the high-temperature steam are effectively treated. In addition, by adopting the composite alkaline treatment agent, gases such as toxic hydrogen sulfide and hydrogen cyanide which are easy to appear in a traditional acid liquor spraying environment are avoided. The invention aims to solve the problems of how to reduce discharged waste gas and condensate, absorb high mercury content in spraying liquid and avoid generation of toxic gases such as hydrogen sulfide and hydrogen cyanide.

The application provides a preparation and application of a catalyst for hydrogen cyanide prepared by direct oxidation of methane and ammonia. The method comprises the following steps: dissolving a soluble platinum salt, a tungsten salt and a cerium salt in water, adding an organic amine to obtain an alkaline metal salt complex solution, and adding methyl glycine diacetic acid trisodium salt MGDA to obtain a three-component solution of metal-organic amine-MGDA; adding the three-component solution into a hydrothermal kettle, adding a silicon source and a template agent, and performing crystallization, washing, drying and calcination to obtain a catalyst precursor encapsulating metal; mixing the catalyst precursor with a promoter and a process aid, adding a binder, and performing extrusion, pelletizing and calcination to obtain a target catalyst. The method solves the problems of harsh reaction conditions, easy carbon deposition of the catalyst and easy loss of platinum in the prior art. The reaction temperature is lower than 600 DEG C, the yield of hydrogen cyanide is greater than 85%, the platinum loss is lower than 0.2 ‰ after 200 h of operation, and the carbon deposition is lower than 0.05 ‰.

A process for producing liquid hydrocarbons from synthesis gas, the process comprising: providing synthesis gas comprising hydrogen cyanide and sulfur compounds; separating the synthesis gas containing hydrogen cyanide and sulfur compounds into a first synthesis gas portion and a second synthesis gas portion; passing the mixture of the first syngas portion and steam through a water gas shift reaction chamber to provide a first syngas portion rich in hydrogen; combining the hydrogen-rich first syngas portion with the second syngas portion to provide a combined syngas; passing the combined syngas through a hydrolysis reaction chamber containing a titanium dioxide catalyst to convert at least a portion of the hydrogen cyanide in the combined syngas to ammonia to provide an ammonia rich, hydrogen cyanide depleted syngas; introducing the ammonia-rich hydrogen cyanide-depleted synthesis gas into a first scrubber and contacting the ammonia-rich hydrogen cyanide-depleted synthesis gas with a first scrubbing liquid, whereby at least a portion of the ammonia contained in the ammonia-rich, hydrogen cyanide-depleted syngas is retained in the first scrubbing liquid to form an ammonia-depleted, hydrogen cyanide-depleted syngas; passing the ammonia-depleted, hydrogen cyanide-depleted syngas through a carbon dioxide removal unit to form a carbon dioxide-depleted syngas; passing the carbon dioxide-depleted syngas to a reaction chamber containing a zinc oxide material to convert at least a portion of the hydrogen cyanide in the carbon dioxide-depleted syngas to ammonia and adsorb residual sulfur compounds present in the carbon dioxide-depleted syngas to provide an ammonia-rich, hydrogen cyanide-depleted desulfurized syngas; introducing the ammonia-rich and hydrogen cyanide-depleted desulfurized synthesis gas into a second scrubber, and contacting the ammonia-rich and hydrogen cyanide-depleted desulfurized synthesis gas with a second washing liquid, whereby at least a portion of the ammonia contained in the ammonia-rich, hydrogen cyanide-depleted desulfurized syngas is retained in the second scrubbing liquid to form an ammonia-depleted, hydrogen cyanide-depleted desulfurized syngas; and passing the ammonia-depleted, hydrogen cyanide-depleted desulfurized syngas through a Fischer-Tropsch reaction chamber to produce a liquid hydrocarbon product.

The invention relates to the technical field of fine chemical engineering, in particular to a continuous synthesis method of glufosinate ammonium, which comprises the following steps: A) mixing diethyl methylphosphonite, acrolein and acetic acid for condensation reaction to obtain a compound a-1; b) mixing the compound a-1 with water, and carrying out a first hydrolysis reaction under the action of a catalyst to obtain a first system; c) returning a part of the first system to the condensation reaction system in the step A), and respectively reacting ethanol and acetic acid with diethyl methylphosphonite and acrolein to generate a compound a; mixing the unreturned part in the first system with an acidic compound, and carrying out a second hydrolysis reaction to obtain a compound c; d) the compound c, an ammonia source and a cyanide source are subjected to a cyanamide reaction to obtain a compound d, the ammonia source is selected from ammonia water or a mixture of ammonia water and ammonium chloride, and the cyanide source is selected from sodium cyanide or hydrogen cyanide, and E) the compound d is subjected to a third hydrolysis reaction to generate glufosinate-ammonium.

The invention relates to the field of chemical synthesis, and discloses a stereoselective synthesis method of R and S-4-chloro-3-hydroxybutyronitrile, which comprises the following steps: S1, carrying out nitrogen displacement on the whole system; s2, diethylamine is added through a diethylamine dropwise adding tank during stirring; s3, after the reaction liquid is transferred, a circulating pump is started for circulation, and the reaction liquid enters from the upper end of the falling-film evaporator; s4, a screw vacuum pump is started, and a gas phase obtained after methanol vaporization is subjected to primary and secondary condensation and then enters a receiving tank; and S5, after material transfer is completed, starting a rectification process. The method comprises the following steps: by taking methanol as a solvent, carrying out nucleophilic addition reaction on R-configuration / S-configuration and hydrocyanic acid under the action of an organic base catalyst diethylamine to obtain R / S-configuration 4-chloro-3-hydroxybutyronitrile, after the reaction is finished, removing the solvent methanol, recycling the part of solvent, further refining a crude product, and purifying to obtain the 4-chloro-3-hydroxybutyronitrile. And the high-purity R / S-configuration 4-chloro-3-hydroxybutyronitrile product is obtained.

The invention relates to a method for exhaust gas aftertreatment comprising the steps of: (a) generating an exhaust gas comprising HCN, NO x and N2O; wherein the HCN content is at least 1.0 ppmv; (b) optional, addition of reducing agent for NO x and / or for N2O into the exhaust gas; and (c)reduce the content of HCN in the exhaust gas by catalytic conversion of the HCN on a transition metal-loaded zeolitic material.

A gas measuring device (100) measures cyanogen in the presence of hydrogen cyanide. The gas measuring device (100) includes a measuring chamber (101), a heating element (103, 203) and an electrochemical sensor (105, 200). The measuring chamber (101) is configured to receive a sample. The heating element (103) is configured to thermally decompose cyanogen contained in the sample into decomposition products. The sensor (105, 200) is configured to detect the decomposition products of cyanogen, which are obtained by the thermal decomposition. A process measures cyanogen in the presence of hydrogen cyanide.

The present invention provides a method for one-step synthesis of adiponitrile. In the method, starting materials butadiene and hydrogen cyanide directly react under the action of a rare earth metal-mixed ligand catalyst and an auxiliary agent to produce adiponitrile, wherein the rare earth metal-mixed ligand catalyst comprises a rare earth metal, a monodentate phosphite ligand, and a multidentate phosphite ligand. According to the present invention, by using the rare earth metal as a catalyst, together with the monodentate phosphite ligand and the multidentate phosphite ligand, the rare earth metal-mixed ligand catalyst with high catalytic performance and high stability is formed, which, in combination with the auxiliary agent, efficiently catalyzes the simultaneous reaction of butadiene with two molecules of hydrogen cyanide to directly obtain adiponitrile. The method greatly simplifies the process flow of producing adiponitrile by using butadiene and hydrogen cyanide as starting materials, and features a high starting material conversion rate, high adiponitrile selectivity, and low operating costs, thus being suitable for large-scale industrial production.