Nitrogen oxide from nitric acid

Sometimes nitrofuroxans are produced. The explosive 3-methyl-4-nitro compound (52) is formed from propene and dinitrogen trioxide or tetroxide when no oxygen is added to the reaction,286,287 and also by the action of nitrous acid on methacrylic acid.127 4-Nitro-3-phenylfuroxan is a by-product of the reaction of nitrogen oxides (from nitric acid and arsenious oxide) and cinnamaldehyde.288... 

Photolytic. Major products reported from the photooxidation of isopropylbenzene with nitrogen oxides include nitric acid and lienzaldehyde (Altshuller, 1983). A / -hexane solution containing isopropylbenzene and spread as a thin film (4 mm) on cold water (10 °C) was irradiated by a mercury medium pressure lamp. In 3 h, 22% of the applied isopropylbenzene photooxidized into a,a-dimethylbenzyl alcohol, 2-phenylpropionaldehyde, and allylbenzene (Moza and Feicht, 1989). 

A process for the industrial production of nitrogen oxide and nitric acid from ammonia and oxygen. 

The four kinds of active carbons used in our laboratory were obtained from different commercial sources and in accordance with supplier information were produced from various precursors. Ash was removed from the raw carbon using concentrated hydrofluoric and hydrochloric acids by Korver s method [166]. Carbon samples were subjected to surface modification by oxidation in air or with concentrated HNO, annealing in a vacuum or an ammonia atmosphere. Afterwards, all carbon samples were desorbed under vacuum (10" Pa) at 150°C (423 K) for 3 h. The procedure used for carhon purification ensured the removal of nitric acid and nitrogen oxides (after nitric acid oxidative modification) or physically sorbed NHi (after heat treatment in ammonia). The samples thus prepared... 

The problem of nitrogen oxides emissions from nylon plants was mentioned previously. Mallinckrodt produces nitrogen oxides when it dissolves metals in nitric acid. By using hydrogen peroxide to oxidize the nitrogen oxides to nitric acid, it has eliminated 30 tons/year of the oxides and reduced its nitric acid use by 109 tons/year.208... 

Fig. 3-7. Vertical distribution of nitrogen oxides and nitric acid in the stratosphere. Left Nitric oxide in the sunlit atmosphere the fields enclose data obtained with the chemiluminescence technique (Horvath and Mason, 1978 Roy et at, 1980 Ridley and Schiff, 1981 Ridley and Hastie, 1981) horizontal lines represent measurements by infrared optical techniques (Drummond and Jarnot, 1978 Roscoe etal., 1981 Loewenstein etal., 1978a,b). Center Nitrogen dioxide as observed by optical measurement techniques, day (d) and night (n) points indicate data from Murcray et al. (1974), Goldman et al. (1978), Blatherwick et at (1980) horizontal bars are from Drummond and Jarnot (1978) and Roscoe et al. (1981). The N205 profile was obtained by Toon et al. (1986) at sunrise. Right Nitric acid observed by in situ filter sampling (open points) (Lazrus and Gandrud, 1974) and by infrared spectroscopy and mass spectroscopy (solid points) (Fontanella et at, 1975 Harries et al., 1976 Evans et al., 1978 Arnold et al., 1980 Murcray et al. as quoted by Hudson, 1982 Fischer et at, 1985). The envelope gives the error range.

When nitrogen dioxide (NO2) from car exhaust combines with water in the air, it forms nitrogen oxide and nitric acid (HNO3), which causes acid rain. (9.1, 9.2, 9.3)... 

Reactions 8 and 9 are important steps for the Hquid-phase nitration of paraffins. The nitric oxide which is produced is oxidized with nitric acid to reform nitrogen dioxide, which continues the reaction. The process is compHcated by the presence of two Hquid phases consequentiy, the nitrogen oxides must transfer from one phase to another. A large interfacial area is needed between the two phases. 

Cu(N03 )26H2 0, is produced by crystallization from solutions below the transition poiat of 26.4°C. A basic copper nitrate [12158-75-7] Cu2(N02)(0H)2, rather than the anhydrous product is produced on dehydration of the hydrated salts. The most common commercial forms for copper nitrate ate the ttihydtate and solutions containing about 14% copper. Copper nitrate can be prepared by dissolution of the carbonate, hydroxide, or oxides ia nitric acid. Nitric acid vigorously attacks copper metal to give the nitrate and evolution of nitrogen oxides. 

This is 90% nitric acid, d. 1.48-1.50. In order to remove dissolved nitrogen oxides from it, 0.5 g. of urea is added and the mixture is air-sparged for 20 minutes. The acid should be colorless before it is added to the acetic anhydride. 

Nitric acid, removal of nitrogen oxides from, 43, 84... 

Yamagushi, M., Matsushite, K. and Takami, K. (1976) Remove nitrogen oxides (NOx) from nitric acid tail gas, Hyd. Proc. 55(8), 101. 

DeNOx (1) A Denox process for removing nitrogen oxides from the gaseous effluents from nitric acid plants. The oxides are reduced with ammonia, over a catalyst containing potassium chromate and ferric oxide. Developed by Didier Werke in the 1980s. 

PuraSiv N A process for removing nitrogen oxides from the tail gases from nitric acid plants, using an acid-resistant zeolite molecular sieve. Developed by the Union Carbide Corporation in 1971. Not to be confused with PuraSiv HR, Type N (see previous entry). 

Dinitroguaiacol, yel pits or ndls (dil ale), mp 121—3° sol in warm dil ale. Prepd from guaiacol in eth at 0° by adding nitrogen oxides from arsenic crioxide nitric acid... 

Noteworthy properties were discovered in ammonium trichromate (NH4)3Cr3O10, produced while crystallizing ammonium bichromate from nitric acid, d = 1.39 (Siewert [47]). At 190°C the compound undergoes explosive decomposition, evolving nitric oxide and nitrogen dioxide. 

Denitration Removal of nitric acid, nitrates or nitrogen oxides from acids and other substances. 

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