Nitric Acid storage

Walker, Hazards Analysis of Holston Ammonium Nitrate/Nitric Acid Storage and Transfer System , Rept No AO8204-520-11-005, Here ... 

C02 —164.9% cryst solid mp 183—85°. Its impact sensy using the PicArsn app with a 2-kg wt was found to be over 100 inches for at least one expln in ten tries. A stoichiometric soln in 100% nitric acid (storage stab at 200°F, 2.0 hrs) has been patented as a monoproplnt Refs 1) Beil, not found 2) R.C. Doss, USP 3031838 (1962) CA57, 7508 (1962)... 

The nitric acid storage tank proposed for this plant will provide a product storage capacity of one week supply in the event of a plant shutdown in the adjacent ammonium nitrate facility. The tank has a capacity of 1950 m3 (representing 1450 tonnes of product acid). 

Absorption column Steam superheater Bleaching column delivery tank Nitric acid storage tank... 

Case Study — Nitric Acid Storage-Tank Design... 

The nitric acid storage tank required for the plant has a capacity of approximately 1950 m3. This represents approximately 2600 tonnes... 

Chemical and processing towers, condensers. Furnace parts such as retorts and low stressed parts subject to temperatures up to 800 "C. Type 430 nitric-acid storage tanks, furnace parts, fan scrolls. Type 430F-pump shafts, instrument parts, valve parts Products requiring high yield point and resistance to shock... 

Amino-4 -methylthiazole slowly decomposes on storage to a red viscous mass. It can be stored as the nitrate, which is readily deposited as pink crystals when dilute nitric acid is added to a cold ethanolic solution of the thiazole. The nitrate can be recrystallised from ethanol, although a faint pink colour persists. Alternatively, water can be added dropwise to a boiling suspension of the nitrate in acetone until the solution is just clear charcoal is now added and the solution, when boiled for a short time, filtered and cooled, deposits the colourless crystalline nitrate, m.p. 192-194° (immersed at 185°). The thiazole can be regenerated by decomposing the nitrate with aqueous sodium hydroxide, and extracting the free base with ether as before. 

A mathematical model of the operating characteristics of a modem HLW storage tank has been developed (60). This model correlates experimental data for the rate of radiolytic destmction of nitric acid, the rate of hydrogen generation owing to radiolysis of water, and cooling coil heat transfer. These are all functions of nitric acid concentration and air-lift circulator operation. 

The materials of constmction for the mixing device and storage vessels must be selected carefully. Glass (qv), polytetrafluoroethylene, or certain kiads of stainless steels are usually used. Glass must be pickled with nitric acid before use. 

On the completion of nitration the batch is dropped from the reaction vessel into a centrifuge and the acid mixture spun off and recovered. The nitrated linters, which still contain appreciable quantities of acid, are then plunged into a drowning tank, where the nitric acid is diluted with a large volume of water. The resultant ester is then pumped, as a slurry, into storage vats which may hold the products of several nitrations. 

Nitric acid treatment lowered the methane uptake by about ten percent. This could be due to oxygen occupying sites within pores, but may be the result of weaker interaction between methane and an oxide surface as is observed for silica. Reduction of these treated carbons with hydrogen restored their original methane uptake. Clearly for methane storage, there is no advantage in modifying the carbon surface by nitric acid treatment. 

Adds One of the most extensive uses of austenitic steels has been for synthetic nitric acid plant, including oxidation coolers, absorption towers, storage vessels and pipelines, as well as transport tanks. For storage of cold 98% acid or for near-boiling solutions above 60% strength, 347S31 or 304S11 should be used. 

Nitric acid readily attacks lead if dilute and the metal should not be used for handling nitrate or nitrite radicals except at extreme dilutions and preferably with a passivating reagent such as a sulphate, which will confer some protection. An example of this is the wash water from cellulose nitrate units. Corrosion decreases to a minimum at 65-70 Vo HNO3 and lead has been used for storage of nitric acid in the cold at this concentration . Resistance to a mixture of 98-85 Vo HjSO and nitric acid of 1 -50-1 -52 S.G. can be excellent °. ... 

On long term storage, moisture can cause undesirable chem reactions such as the formation of nitric acid, which can react with such metals as Al, Mg, Fe, Cu, etc, to yield H2. The H2, in turn, in redox reactions with both metals and org chemicals present can form shock sensitive compds (Refs 6, 11, 12, 15, 17 26). 

In the production of TNT from the reaction between toluene and mixed acids (nitric/sulfuric), TeNMe forms in amounts between 0.2—0.4% of the total wt of TNT. This TeNMe has been held responsible for several expins which have occurred in TNT plants, causing fatal injuries to personnel and severe damage to facilities. These expins were attributed to the presence of TeNMe in the acid fume lines and the acid storage tanks. Mixts of TeNMe and readily oxidizable materials are known to form very powerful and sensitive expl mixts. Since TeNMe is also isolated from the nitration of Nitrobenzene (NB), the TeNMe formed in the nitration of toluene may arise from the oxidation of the aromatic ring and/or methyl group. In an effort to gain more informa-. tion on the origin of TeNMe from TNT production, radioactive carbon-14 (14C) was used as a tracer to determine the extent to which each of the carbon atoms in the toluene skeleton of the various nitro-substituted isomers contributes to... 

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