45 results about "Hydrogen cyanide gas" patented technology

The invention discloses an ammonia recovery method from the mixing gas produced in the process of hydrogen cyanide production, comprising ammonia absorption process, decyanation process, desorption process and rectifying process for solving the technical problem. The invention is characterized in that decyanation process is set separately to recovery hydrogen cyanide gas, avoiding the loss of hydrogen cyanide caused by a large amount of acid gas like hydrocyanic acid contained in the ammonium phosphate solution directly steamed in Versum method, reducing production cost of hydrogen cyanide, reducing the emission of the harmful acid gas like hydrogen cyanide, and avoiding the serious pollution of peripheral enviroment. Besides, the ammonium phosphate solution contains a much smaller amout of hydrocyanic acid after hydrogen cyanide is recovered, which can not influence production process and make the production process more safety.

The invention relates to a nano sensitive material for monitoring hydrogen cyanide. The nano sensitive material is characterized by consisting of the following components in percentage by weight: 25 to 35 percent of NiO, 30 to 40 percent of V2O5 and 32 to 42 percent of Al2O3 nano powder. The particle size of the nano sensitive material is between 25 and 40nm. A hydrogen cyanide air sensor made of the nano sensitive material has the advantages of wide linear range, high selectivity and high sensitivity, and can monitor a trace amount of hydrogen cyanide on line without being influenced by coexisting substances.

The invention discloses a detection apparatus and detection method for hydrogen cyanide in a research lab. The detection apparatus comprises a controller, a memory, a base plate, a rectangular cross section equipped air chamber and a support frame arranged on the base plate, and a guide structure and a cross lead screw arranged on the support frame. The inner wall top of the air chamber is provided with an ultrasonic generator and several fans for blowing down, the inner side wall of the air chamber is equipped with a gas sensitive film, a metal net composed by heating wires and for supporting the gas sensitive film, a horizontal separator plate that is located below the metal net and separating the inside of the air chamber into an upper part and a lower part from top down in order, and the air chamber is internally provided with an ultrasonic receiver, a support plate, a detection head and a track spirally distributed along the upper surface of the support plate. The detection apparatus provided by the invention has the characteristics of high sensitivity, good stability and short response time, good selectivity to hydrogen cyanide, and ability to detect lower concentration trace hydrogen cyanide gas, thus effectively guaranteeing people good health.

The invention discloses a reactor used for preparing gas-phase hydrogen cyanide. The reactor used for preparing gas-phase hydrogen cyanide comprises an upper sealing head, a lower sealing head, a shell side and reaction tubes, wherein the reaction tubes are arranged in the shell side; the upper sealing head and the lower sealing head are respectively and correspondingly mounted at the upper end and the lower end of the shell side; the reactor used for preparing gas-phase hydrogen cyanide also comprises a feed gas distribution device, a temperature monitoring device, a heat-transfer medium flow guide device and a hollow flow guide cylinder; the feed gas distribution device is mounted in the top end of a main body structure of the tubular reactor; the temperature monitoring device is inserted from the top end of the main body structure of the tubular reactor; the heat-transfer medium flow guide device is mounted on the outer part of the shell side; flow guide holes are formed in an inner wall surface, being in contact with the heat-transfer medium flow guide device, of the shell side; the hollow flow guide cylinder and the reaction tubes are mounted in the shell side in a mixing manner. The reactor used for preparing gas-phase hydrogen cyanide has the beneficial effects of being capable of generating easily-separated hydrogen cyanide gas and stably and effectively dissipating reaction heat, an accurate reaction temperature monitoring system is arranged, the feed gas distribution effect is good, the reaction conversion rate is high; a catalyst is low in loss during use and long in service life.

The invention provides a technological method for jointly preparing liquid hydrogen cyanide and bisisobutyronitrile hydrazine. The technological method comprises the steps that a light oil cracking hydrogen cyanide gas mixture is used as a raw material and undergoes an ammonia removal process and a cryogenic process to obtain liquid hydrogen cyanide, wherein in the ammonia removal process, the hydrogen cyanide gas mixture is absorbed with a sulfuric acid aqueous solution; in the cryogenic process, the hydrogen cyanide gas mixture is cooled to minus 10-minus 20 DEG C, after the hydrogen cyanide gas mixture is cooled, a part of the hydrogen cyanide gas becomes liquid to obtain liquid hydrogen cyanide, and the other part of the hydrogen cyanide gas is the tail gas containing hydrogen cyanide; the tail gas containing hydrogen cyanide, which undergoes cryogenic treatment, is absorbed with a ketazine aqueous solution to obtain an aqueous solution containing bisisobutyronitrile hydrazine, and the aqueous solution containing bisisobutyronitrile hydrazine undergoes cooling, crystallization and centrifugal filtration to obtain a bisisobutyronitrile hydrazine crystalline solid. By adopting the technological method, the purification efficiency and the utilization efficiency of hydrogen cyanide can be obviously improved, meanwhile, the energy consumption in the hydrogen cyanide purification process is greatly reduced and can be reduced by 90% at most, and the utilization rate of hydrogen cyanide is more than 99.9%.

The invention relates to a harmless method for treating cyanide-containing tailings pulp with a biological oxidation liquid in a gold extraction process in the gold industry, and belongs to the field of environmental protection. First, a closed stirring reactor is selected, and an air drainage device is installed on the upper part of the reactor. The hydrogen cyanide gas that may be generated in the reaction is introduced into the spray absorption device for absorption, and then the biological oxidation solution is added to the reactor, which will easily release cyanide and metals. Removal of cyanide complexes; the tailings slurry is filtered or press-pressed, and the tailings slag that is identified as general industrial solid waste is piled to the tailings pond; the filtrate is added with a pH neutralizer, reused in the production process or added to the filtrate Advanced treatment of chemicals and catalysts, the filtrate treatment to meet GB8978‑1996 "Integrated Wastewater Discharge Standard" for discharge. The invention treats waste with waste, and enterprises do not need to purchase harmless treatment chemicals, which greatly reduces the operating cost of gold production enterprises, and is of great significance to the clean production, energy saving and emission reduction and sustainable development of the entire gold industry.

The invention relates to the technical field of organic synthesis, in particular to a method of continuously preparing a substituted benzyl cyanide compound by using a microchannel reactor, and discloses a preparation method of substituted benzyl cyanide. The preparation method comprises the steps of preheating accurately metered raw materials, namely substituted benzyl halide and hydrogen cyanide gas separately, allowing the raw materials to enter a microchannel reactor after mixing for nucleophilic substitution reaction at 150.0-250.0 DEG C and pressure of 1.0-10.0MPa to generate substituted benzyl cyanide and hydrogen halide, keeping reaction retention time for 10-300s, then cooling for quenching reaction, and post-treating a reaction material to form substituted benzyl cyanide. The method has the advantages of low cost, high production efficiency, continuous production and clean production.

The invention provides a technological method for jointly preparing liquid hydrogen cyanide and hydroxynitrile. The technological method comprises the steps that a light oil cracking hydrogen cyanide gas mixture is used as a raw material and undergoes an ammonia removal process and a cryogenic process to obtain liquid hydrogen cyanide, wherein in the ammonia removal process, the hydrogen cyanide gas mixture is absorbed with a sulfuric acid aqueous solution; in the cryogenic process, the hydrogen cyanide gas mixture is cooled to minus 10-minus 20 DEG C, after the hydrogen cyanide gas mixture is cooled, a part of the hydrogen cyanide gas becomes liquid to obtain liquid hydrogen cyanide, and the other part of the hydrogen cyanide gas is the tail gas containing hydrogen cyanide; the tail gas containing hydrogen cyanide, which undergoes cryogenic treatment, is absorbed with a formaldehyde aqueous solution containing a catalyst to prepare a hydroxynitrile aqueous solution, and the tail gas absorbed with the formaldehyde aqueous solution directly enters an incinerator to be incinerated. By adopting the technological method, the purification efficiency and the utilization efficiency of hydrogen cyanide can be obviously improved, meanwhile, the energy consumption in the hydrogen cyanide purification process is greatly reduced and can be reduced by 90% at most, and the utilization rate of hydrogen cyanide is more than 99.9%.