• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    A process for the preparation of nitric acid of different concentrations, and preferably of a concentration below 75 percent (weak acid) and of about 98 percent (highly concentrated acid) comprising oxidizing catalytically ammonia and air under pressure to form nitrous gas, oxidizing the NO contained in the gas in a first oxidation step with subsequent chemical absorption of the oxidized NO into a nitric acid obtained in a preceding covering step, whereby a weak nitric acid is formed, and oxidizing the NO remaining in the nitrous gas in a second oxidation step completely to NO2, removing the NO2 from the gas by physical absorption into highly concentrated nitric acid, separating the NO2 from the nitric acid, liquefying the NO2 and oxidizing the liquefied NO2 with aqueous nitric acid to obtain highly concentrated nitric acid.
    公开号:SU786879A3
    申请号:SU701410926
    申请日:1970-02-27
    公开日:1980-12-07
    发明作者:Хелльмер Ларс；Нолле Вольфганг
    申请人:Дэви Интернациональ Аг (Фирма)；
    IPC主号:
    专利说明:

    This invention relates to a process for the preparation of nitric acid in various concentrations, especially less than 75% (weak acid), and approximately 98% (highly concentrated acid) from gases produced during the combustion of NHoj. A method of producing weak nitric acid is known by catalytic oxidation of c1miac under pressure, followed by cooling of nitrous gases, by partial condensation of water vapor. Nitric oxide is oxidized to dioxide and absorbed in the aqueous phase. In order to simultaneously produce concentrated nitric acid, a method has been proposed, consisting in that nitric oxide in nitrous ha is completely oxidized to nitrogen dioxide; nitrogen is separated from the gas stream by absorption by concentrated nitric acid, followed by separation of nitrogen dioxide from acid by distillation, liquefaction and oxidation of the separated gases in the presence of oxygen and dilute nitric acid. The method is carried out as follows. According to the described scheme, they form in a ratio of 1: 1.2 highly concentrated (99%) and weak (60%) acids. During the combustion of ammonia, gases formed under a pressure of 9.5 atm. The reaction gas is cooled, and the residual gas is heated to. In this heat exchange, the residual gas is simultaneously mixed with a weak acid, and the residual gas is largely saturated with water vapor. In the case described, this process occurs in the heat exchanger pipelines when the acid is saturated from 55 to 57%. The reaction gas is then cooled, and approximately 35% acid is formed with condensed water, which is then taken off. At the bottom of the oxidation-absorption column, the degree of oxidation required is controlled, and the heat generated is removed through hoses in the sieve plates. In the middle part of the column, by chemical absorption on sieve plates, 55% acid is formed, and the condensate formed upon cooling is introduced. Taken out of gas
    oxides of nitrogen required to form a weak acid.
    The remaining nitrogen oxides contained in the gas are used to produce highly concentrated acid. In the degassing column, the resulting acid is freed from the nitrogen oxides contained in it by introducing air from the outside.
    In the upper part of the oxidation-absorption column, nitric oxide still contained in the gas is completely oxidized, and the reaction gas is cooled in the heat exchanger with the help of waste cold residual gases. A gas cooler operating on a cooling salt source serves to further cool the gas. This produces an acid condensate, which, like the condensate formed during the oxidation step in the oxidation-absorption column, is introduced into an autoclave to produce a highly concentrated nitric acid. In the column, by physical absorption with highly concentrated acid, nitrogen dioxide contained in it is washed out of the gas. This process is carried out by means of serrated plates cooled by ishangs. With the help of a salt source, the level of absorption temperatures is controlled in such a way that the required nitrosis content in the gas is achieved.
    The gas leaving the column is practically free of nitrogen oxides (less than 200 ppm),
    The nitrogen dioxide-rich acid is heated and introduced into the bleaching column. The nitrogen dioxide, after passing through a reflux condenser, is liquefied in a refrigerator and, together with a weak acid, enters the autoclave, where, when oxygen is introduced from the outside at a pressure of approximately 50 atm, superconcentrated
    nitric acid (hoko), The resulting acid, still containing nitrogen dioxide, is degassed and bleached. A portion of pure concentrated acid, collected in the lower part of the column, after cooling, is withdrawn, and a portion is used, after cooling, as an absorbent of nitrogen dioxide by physical absorption.
    Weak acid with a concentration of 57% is subjected to rectification. To keep the temperatures low, the rectification is carried out under vacuum.
    The distilled water vapor is partially diluted in a reflux condenser and completely condenses. The 60% acid that collects at the bottom of the column is removed from the column.
    权利要求:
    Claims (1)
    [1]
    Invention Formula
    The method of obtaining nitric acid with a concentration of up to 75% by oxidizing ammonia under elevated pressure, followed by cooling the resulting nitrous gases and condensation of water vapor — with the formation of weak nitric acid by oxidizing nitric oxide in nitrous gas to nitrogen dioxide, and absorbing it with the weak nitric acid that differs so that, in order to simultaneously produce a highly concentrated nitric acid with a concentration of about 98%, the nitric oxide in the nitrous gas is completely oxidized to nitrogen dioxide, separated from the gas lumen output by absorption of concentrated nitric acid followed by separation of nitrogen dioxide from the concentrated acid by distillation, liquefaction and oxidation of the separated gases and oxygen in the presence of dilute nitric acid.
    类似技术:
    公开号 | 公开日 | 专利标题
    US2135271A|1938-11-01|Method of recovering olefin oxides from gaseous mixtures and hydrolyzing to form corresponding glycols
    SU786879A3|1980-12-07|Method of nitric acid production
    US1989267A|1935-01-29|Production of nitric acid and liquid nitrogen tetroxide
    EP0009545B1|1982-12-08|Acrylic acid recovery with recycle quench
    US2088057A|1937-07-27|Production of nitric acid from oxides of nitrogen
    US3716625A|1973-02-13|Process for the production of nitric acid with a concentration of over 70 percent by weight
    FI62270C|1982-12-10|FOERFARANDE FOER UTVINNING AV FLYTANDE SVAVELDIOXID
    RU2112768C1|1998-06-10|Method for uninterrupted production of aqueous solutions of formaldehyde
    US1948968A|1934-02-27|Preparation of nitrogenous products
    US2046162A|1936-06-30|Process for producing concentrated nitric acid
    US2169210A|1939-08-15|Recovery of olefin oxides from
    US3868443A|1975-02-25|Process for the manufacture of nitric acid
    US4055627A|1977-10-25|Process for treating gases in the ammonia synthesis
    US2510684A|1950-06-06|Process for the manufacture of sulfur trioxide
    GB803211A|1958-10-22|Improvements in and relating to the production of nitric acid
    US4064221A|1977-12-20|Process for obtaining nitric acid of a concentration higher than the azeotropic concentration by means of the absorption of nitrogen oxides in water or diluted nitric acid
    GB456518A|1936-11-05|Improvements in or relating to the production of highly concentrated nitric acid
    US4983260A|1991-01-08|Process for concentrating aqueous ethylene oxide solutions
    US3362786A|1968-01-09|Sulfur trioxide production
    US2018249A|1935-10-22|Process of carrying through gas reactions
    US2215450A|1940-09-24|Process for the production of a nitrate
    US1324255A|1919-12-09|Jensen
    US3102788A|1963-09-03|Production of pure nitrogen tetroxide
    US2181559A|1939-11-28|Process for producing a nitrate
    US1590043A|1926-06-22|Production of concentrated nitric acid from waste acids
    同族专利:
    公开号 | 公开日
    NL7002858A|1970-09-30|
    BE747201A|1970-08-17|
    FR2039913A5|1971-01-15|
    GB1298843A|1972-12-06|
    DK133594B|1976-06-14|
    US3634031A|1972-01-11|
    DK133594C|1976-11-01|
    SE369296B|1974-08-19|
    ES377281A1|1972-06-16|
    AT299980B|1972-07-10|
    DE1916814A1|1970-11-05|
    CA927077A|1973-05-29|
    CS181202B2|1978-03-31|
    PL85182B1|1976-04-30|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US1989267A|1926-11-09|1935-01-29|Caro Nikodem|Production of nitric acid and liquid nitrogen tetroxide|
    US1948968A|1931-08-08|1934-02-27|Shell Dev|Preparation of nitrogenous products|
    US3070425A|1959-10-15|1962-12-25|Allied Chem|Production of nitrogen tetroxide|
    GB1051100A|1963-08-15|1900-01-01|
    US3389960A|1964-08-31|1968-06-25|Du Pont|Process for producing strong nitric acid|DE2148329A1|1971-09-28|1973-04-05|Uhde Gmbh Friedrich|PROCESS FOR THE PRODUCTION OF NITRIC ACID|
    IT1030938B|1974-12-20|1979-04-10|Sir Soc Italiana Resine Spa|IMPROVEMENTS IN PROCEDURES FOR THE PREPARATION OF CONCETRATED NITRIC ACID|
    FR2369210B1|1976-10-29|1979-02-23|Robichon Patrice|
    AU2011335886B2|2010-12-01|2013-02-14|The University Of Sydney|Process for producing ammonium nitrate|
    BR112013013700B1|2010-12-01|2020-04-07|Orica Int Pte Ltd|process for the production of nitric acid|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    DE19691916814|DE1916814C|1969-03-28|Process for the simultaneous production of nitric acid of different concentrations|
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