Transport of nitric acid

Close scheduling is recommended for the transport of nitric acid that has a concentration above 99%. For truck shipments the maximum recommended transport time is three (3) days while rail shipments have a recommended transport time of five (5) days97. 

Bennett Mid his co-workeis [43] confirmed this interpretation of the cryometric investigations. To prove definitely the existence of the N02+ ion, they attempted to show that when electrolysed, the ion is transported towards the cathode. They did not succeed in obtaining full evidence for this, although they found that nitric acid moves away from the Miode. It was only when the electrolysis was carried out in the presence of oleum Mid barium salts, that the transport of nitric acid towards the cathode was confirmed. Studying the cathodic polMization of nitric acid Mint [44] observed the evolution of nitrogen dioxide at the cathode. This may be mi additional piece of evidence for the trMisport of mi ion containing nitrogen (probably N02+) towMds the cathode. 

Membrane Systems and Experiments. The transport of nitric acid through a supported liquid membrane (SLM) containing trilaurylamine (TLA) as carrier was studied using a single hollow fiber module. 

Palaty Z. and Zakova A., Transport of nitric acid through the anion-exchange membrane NEOSEPTA-AFN, Desalination 160, 51, 2004. 

Chemical Reactivity - Reactivity with Water Reacts to form weak solution of nitric acid, however the reaction is usually not considered hazardous Reactivity with Common Materials In presence of moisture will attack and damage wood and corrode most metals Stability During Transport Stable Neutralizing Agents for Acids and Caustics Not pertinent Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

In contrast to the equilibrium electrode potential, the mixed potential is given by a non-equilibrium state of two different electrode processes and is accompanied by a spontaneous change in the system. Besides an electrode reaction, the rate-controlling step of one of these processes can be a transport process. For example, in the dissolution of mercury in nitric acid, the cathodic process is the reduction of nitric acid to nitrous acid and the anodic process is the ionization of mercury. The anodic process is controlled by the transport of mercuric ions from the electrode this process is accelerated, for example, by stirring (see Fig. 5.54B), resulting in a shift of the mixed potential to a more negative value, E mix. 

In the United States the Department of Transportation (DOT) defines three categories of nitric acid 1) nonfuming, more than 70 wt % acid 2) nonfuming, less than 70 wt % acid and 3) red fuming nitric acid. All must be labeled corrosive . Red fuming acid must also be labeled oxidizeT and poison. ... 

Storage and Distribution. Nitric acid is normally stored in flat-bottomed, roofed tanks that are made from low-carbon, austenitic stainless steel. Most concentrations of nitric acid are transported in tank cars and by truck. Stainless steel is necessary for concentrations up to 80 to 85 percent. Stronger solutions are less corrosive and may be stored in aluminum. 

There are, however, a number of species that have either photochemical lifetimes of an intermediate range or altitude profiles controlled by transport processes. Nitric acid and the peroxides are good examples of the former case, and their altitude profiles, when calculated from a purely photochemical model, may not be quantitatively correct. In the latter case, water and ozone being excellent examples, it is necessary to use measured altitude profiles that remain fixed and independent of the photochemical model. 

Danesi et al. studied the kinetics of transport of Am(lll) from aqueous nitrate solutions to formic acid aqueous solutions using an SLM, which consisted of a solution of a new (carbamoylmethyl)phosphine oxide in diethylbenzene (DEB) [110]. In an attempt to treat simulated low-level radioactive wastewater, Teramoto et al. [Ill] have used an SLM containing CMPO for the uphill transport of Ce(III) from aqueous solution containing a mixmre of nitric acid and sodium nitrate. The simulated waste contained Ce(III), Fe(III), Cr(III), and Ca(II), while the strip solution contained water or sodium citrate solution. Though TBP has been used along with CMPO and w-dodecane as the carrier solution, it also facilitates the transport of HNO3 to the strip side. The acid transport was significantly decreased when CMPO alone in 2-nitrophenyl octyl ether was used as the carrier solution. 

Metal films and powders are scarcely applied in practical catalysis, but gauzes are used, for example, in the oxidation of NO for the manufacture of nitric acid. The Pt catalyst is so active that the rate of reaction is largely determined by how fast the reactants are transported through the gas phase to the gauze surface therefore, there is little practical incentive to increase the surface area of the metal by dispersing it on a support. Occasionally, metals are used as porous solids with internal surface areas of 10 mVkg or more. Porous Raney nickel particles are used for hydrogenation of fats. The pore structure in the nickel is formed by extraction of A1 from a Ni— A1 alloy with NaOH. 

Effect of Nitric Acid. Preliminary experiments showed Incomplete transfer of americium from 7.0M nitric acid through a membrane of undiluted DHDECMP to 0.25M oxalic acid. Danesl et al. ( ) have shown that such membranes also transport nitric acid. Consequently, the nitric acid concentration of the strip solution Increases with time and the driving force of the transfer, the nitrate concentration gradient. Is neutralized. When this occurs, equilibrium Is reached and no further net changes In americium concentration are observed. See Horwltz al. ( ) for the equations describing the chemistry of the extraction. 

It is self evident that novel products must satisfy human needs if they are to become the basis of commercial manufacturing processes. The range of organic products changed as a result of World War I, particularly with the increased use of electrical equipment and motorized transport. Further, the absence of previously abundant raw materials, as well as the fear of shortages, stimulated research and development in both Allied and German academic and industrial laboratories. Work on the production of nitric acid from synthetic ammonia, and on synthetic petroleum and synthetic rubber, underscored the new needs, particularly the growing reliance on new industries. It mattered little that the basic chemistry was not understood. It was more important that the new products could be easily processed by users. 

Some of the alloys that are protected by anodic protection are stainless steel in phosphoric acid, steel in sulfuric acid, nickel in nitric acid, nickel alloys in nitrate solutions, and titanium in ammonia solution. Recently, anodic protection has been used to protect stainless steel heat exchangers used in the production of sulfuric acid [57]. The current requirement for some of the steels on which anodic protection has been applied is summarized by Sudbury and Locke [58]. Anodic protection has also been used in plants for the manufacture, storage, and transport of sulfuric acid. It reduces the iron dissolution in sulfuric acid to 1 ppm per day of storage. Portable anodic protection systems are used to stop iron dissolution during the transportation of sulfuric acid in trucks [57]. 

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