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Nitric acid formation

Caustic soda by reaction of sodium amalgam and water Nitration of organic compounds with aqueous nitric acid Formation of soaps by action of aqueous alkahes on fats or fatty acids Sulfur removal from petroleum fractious by aqueous ethauolamiues Treating of petroleum products with sulfuric acid... [Pg.706]

Ammonium nitrate is manufactured by reacting ammonia with nitric acid. Consider the process shown by Fig. 9.19. First, namral gas is reformed and converted into hydrogen, nitrogen and carbon dioxide. Hydrogen and nitrogen are separated an fed to the ammonia synthesis plant. A fraction of the produced ammonia is employed in nitric acid formation. Ammonia is first oxidized with compressed air then absorbed in water to form nitric acid. Finally nitric acid is reacted with anunonia to oduce ammonium nitrate. [Pg.240]

C06-0021. Determine the energy change per mole of NH3 consumed for the first step in nitric acid formation, reaction of ammonia with oxygen ... [Pg.410]

Russell, A. G., and G. R. Cass, Verification of a Mathematical Model for Aerosol Nitrate and Nitric Acid Formation and Its Use for Control Measure Evaluation, Atmos. Enriron., 20, 2011-2025 (1986). [Pg.292]

Barelko, E.V., Solyanina, I.P. 1973. Radiolysis of solutions of TBP in contact with nitric acid. Formation of radiolysis products of the extraction reagent. Atomic Energy 35(4) 898-902. (Translated from Atomnaya Energiya 35(4) 239-243.)... [Pg.500]

The extent of the influence of NO in any given atmospheric situation depends on its sources, reservoir species and sinks. Therefore, an important atmospheric quantity is the lifetime of NO . If nitric acid formation is considered to be the main loss process for NO i.e. NO2), then the lifetime of NO ( no ) can be expressed as the time constant for reaction (2.23), the NO2 to HNO3 conversion. [Pg.27]

Extrapolation to the K/T boundary requires consideration of the time scales of acid deposition. Nitric acid formation occurs rapidly by aqueous phase reaction of NO and NO2 with liquid water produced by tlie incident K/T bolide on both impact and infall of ejecta. For tlie quantities of NO produced by the K/T impact ( 10 5 moles), conversion to HNO3 occurred wiUiin days, assuming sufficient liquid water was available in the posl-K/T atmosphere. The nitric acid will form an acid rain of pH 0 for a liquid water content of 1 g/m (typical of tropospheric clouds) but will contain enough protons to weather only 3 x 10 moles of Sr, for Sr/(Ta -0.003 in soil and bedrock minerals. Sulfuric acid formation occurred on a time scale of years [7] due to the slow rate of gas phase SO2 oxidation. Spread evenly over 10 years, 10 moles of SO2 produced a global acid rain of pH —4, and released —3 x 10 moles of Sr. [Pg.235]

This paper deals with the hydrothermal deactivation, under an air + 10 vol. % H2O mixture between 923 and 1173 K, of Cu-MFI solids, catalysts for the selective reduction of NO by propane. Fresh and aged solids were characterized by various techniques and compared with a parent H-ZSM-5 solid. The catalytic activities were measured in the absence and in the presence of water. The differences between fresh and aged Cu-ZSM-5 catalysts (destruction of the framework, extent of dealumination...) were shown to be small in spite of the strong decreases in activity. Cu-ZSM-5 is more resistant to dealumination than the parent H-ZSM-5 zeolite. The rate of NO reduction into N2 increases with the number of isolated Cu VCu ions. These isolated ions partially migrate to inaccessible sites upon hydrothermal treatments. At very high aging temperatures a part of the copper ions agglomerates into CuO particles accessible to CO, but these bulk oxides are inactive. Under catalytic conditions and in the presence of water, dealumination is observed at a lower temperature (873 K) than under the (air + 10 % H2O) mixture, because of nitric acid formation linked to NO2 which is either formed in the pipes of the apparatus or on the catalyst itself... [Pg.335]

Hydroxyl radical losses occur almost exclusively via reaction with NO2 to form HNO3. Between VOC/NO = 4 and 8 an increase in OH concentration is sufficient to offset the decrease in the amount of NO2 present, causing nitric acid formation to remain relatively constant (77 ppb at VOC/NO, = 4 and 79 ppb at VOC/NO, = 8), but at high VOC/NO,... [Pg.306]

Since nitric acid concentrations are high in Pasadena samples, the mechanism of nitric acid formation in rainwater is of interest. The equilibrium models for the gas scavenging of NO species are given in equations 12-16. Other equations may be written for intermediate reactions in both the gaseous and liquid phases, but equations 12-16 determine the overall equilibrium. [Pg.119]

Nitric acid can be formed by the radiolysis of moist air. This nitric acid will rapidly dissolve in water and cause a decrease in the pH. On the other hand, intermediate products in the air radiolysis process interact rapidly with surfaces and other chemical species in the atmosphere. Furthermore, nitric acid is susceptible to decomposition in a radiation field. It has been difficult, then, to assess the overall effect nitric acid formation by radiolysis will have on solution pH. [Pg.57]

C B. Ashmore and H.E. Sims, Nitric acid formation in irradiated moist air, AEAT-0570, AEA Technology, Winfrith, Dorset, United Kingdom, October 1996. [Pg.73]

The present paper briefly surveys the current situation on the compatibility of materials used in the Winfrith SGHWR and possible future versions, and discusses how this may be affected by the choice of water chemistry for the system. Broadly this entails operating the reactor neutral, under oxidizing conditions due to radiolysis, or with an ammonia addition which must be at a sufficient level to produce reducing conditions, l.e., supress oxygen formation and hence nitric acid formation. [Pg.127]


See other pages where Nitric acid formation is mentioned: [Pg.677]    [Pg.680]    [Pg.43]    [Pg.374]    [Pg.105]    [Pg.677]    [Pg.680]    [Pg.198]    [Pg.128]    [Pg.323]    [Pg.222]    [Pg.90]    [Pg.121]    [Pg.532]    [Pg.226]    [Pg.240]   
See also in sourсe #XX -- [ Pg.975 , Pg.976 ]

See also in sourсe #XX -- [ Pg.350 ]




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