Nitrate secondary production

This secondary reaction starts at about 180°C, but the mass must be heated to 350—400°C to bring the reaction to completion and produce a nitrate-free product. The off-gases are extremely corrosive and poisonous, and considerable attention and expense is required for equipment maintenance and caustic-wash absorption towers. Treatment of the alkaline wash Hquor for removal of mercury is required both for economic reasons and to comply with governmental regulations pertaining to mercury ia plant effluents. 

Many activations involve compounds which are used as pesticides. In the case of N-nitrosation, the precursors are secondary amines and nitrate. The former are common synthetic compounds and the latter is an anion found in nearly all solid and aqueous phases. The N-nitrosation of a secondary amine [R-NH-R ] occurs in the presence of nitrite formed microbiologically from nitrate. The product is an N-nitroso compound (i.e., a nitrosamine [RR -N-N=0]). The reason for concern with nitrosamines is their potency, at low concentrations, as carcinogens, teratogens, and mutagens. 

At this site in the eastern tropical North Pacific, denitrification is responsible fiar the midwater loss of nitrate and production of nitrite. The size of the secondary nitrite maximum is dependent on the relative rates of its production from NO3 and its loss via dissimilatory reduction to N2. The amount of nitrate lost to denitrification is shown as the difference between the measured nitrate and the calculated nitrate. The latter was estimated by multiplying the observed phosphate concentrations by the average nitrate-to-phosphate ratio in the three deepest samples (11.9 1.6pmolN/L). Note that the zone of denitrification is restricted to mid-depths, i.e., the depths of the OMZ at this site. 

Barton and Narang" have prepared nitrate esters by treating primary and secondary alky-lamines with dinitrogen tetroxide in the presence of an amidine base like DBU. Wudl and Lee " conducted deamination reactions without any amidine base and reported much lower yields of nitrate ester product. The use of an amidine base is not necessary if the amine substrate... 

According to the vendor, this project could provide a compact, low-cost reactor to treat aqueous mixed waste streams containing nitrates or nitrites, eliminate the need for chemical reagents, and minimize or eliminate secondary wastes such as nitrous oxide and secondary products such as ammonia, H2, and O2 that are prevalent with other nitrate destruction processes. By removing nitrates and nitrites from waste streams before they are sent to high-temperature thermal destruction and vitrification, production of NO can be decreased with the attendant decrease in off-gas system requirements. Biocatalytic nitrate destruction is applicable to a wide range of aqueous wastes with a highly variable composition. All information is from the vendor and has not been independently verified. 

On the other hand, Elliott and his co-workers 4 maintain that the evidence for the nitro- structure is unsatisfactory, and that the p-nitro-dimethylaniline produced with dimethylaniline is a secondary product obtained either by oxidation of the nitroso-compound or by direct nitration of the amine. The addition of ethyl hydrogen sulphate to a solution of nitrosulphonic acid in sulphuric acid does not yield nitro -ethane. Elliott suggests that the crystalline acid is essentially the nitroso- form, ON. O. SO 2. OH, but that in the molten condition and in sulphuric acid solution this form is in equilibrium with another of yO ... 

MP 41, 364-68(1959) 1,l -Dinitramino-N-nitro-dimethylamine (called Trinitrodiaminodimethylamine by DiCerrione), 02N.N(CH2NHN02)2> mw 310.12, N 26.93%. A secondary product formed in the nitration of hexamethylenetetramine to trimethylenetrinitramine. Description of this compd is not given in the abstract (Ref 2) Refs 1) Beil — not found 2) A. DiCerrione, AnnChimApplicata 38, 255(1948) CA 43, 4633(1949) 3) Not found in later refs thru... 

Tiiis process consists of continuous nitration of hexamine with nitric acid (98.5%), conliruious decoinpositiorr of the secondary products formed during nitration and continuous nitration of KUX from its spent acid. 

More research is required in order to understand the health effects of secondary products like ketones, peroxy-acetyl nitrate and organic acids, which are generated from the reactions of VOCs in indoor air [125]. 

Point sources are a relatively small contributor of NO emissions compared to S02, but still substantial. Both NO and N02 have low solubility in water. Virtually no NO is removed from fresh plumes. HN03 formed by gas-phase oxidation of N02 is very soluble in water and the principal source of nitrate in precipitation. Since the secondary products are much more easily scavenged than NO, its scavenging increases with plume dilution and oxidation. Mesoscale studies show much variation in the efficiency of wet scavenging of SO and NO, depending on the storm type and plume history. About one-third of the anthropogenic NO emissions in the United States are estimated to be removed by wet... 

The primary products which were quantified include 3-hexyl nitrate, 2-hexyl nitrate, n-butyl nitrate, 3-hexanone, 2-hexanone, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and 5-hydroxy-2-hexanone. 2,5-hexanedione was quantified but is thought to be a secondary product, and 5-nitrooxy-2-hexanol was detected but reliable quantification was not possible. 

Secondary products, formed from in situ atmospheric photochemical reactions, include the alkyl nitrates, peroxyacyl nitrate, and mat r other compounds. In general, the contribution of these species is usually fairly modest (a few percents) compared to the inoiganic species already mentioned. However, because some of these compounds have well-documented health implications (e g., PAN, ni-trosamines, lutroarenes) and because some of these can play roles in regulating the chemistiy of ozone (eg., PAN),... 

Another new cerium(IV) reagent, ceric triethylammonium nitrate (CTEAN), has been prepared for use in the mild high-yield oxidation of benzyUc alcohols and a-hydroxy ketones to the corresponding carbonyl compounds (Firouzabadi and Iranpoor, 1983). This CAN analog is stable, soluble in methylene chloride, acetonitrile, acetone, alcohols and water it gives high yields in simple, nonacidic solvents and produces minimal secondary products from carbon-carbon bond cleavage. 

Sempeles and Andino (2000) suggested that propanal could be a secondary product, resulting from the formation and subsequent oxidation of an organic nitrate, CH3CH2CH(0N02)0CH2CH2CH3 ... 

The carcinogenicity of nitrosamines has created widespread concern over the safety of food products that are significant sources of nitrates and nitrites. Nitrosamines are readily formed by reaction of secondary amines with nitrites at acid pH, conditions which may occur in the gastrointestinal tract. 

When nickel hydroxide is oxidized at the nickel electrode in alkaline storage batteries the black trivalent gelatinous nickel hydroxide oxide [12026-04-9], Ni(0H)0, is formed. In nickel battery technology, nickel hydroxide oxide is known as the nickel active mass (see Batteries, secondary cells). Nickel hydroxide nitrate [56171-41-6], Ni(0H)N02, and nickel chloride hydroxide [25965-88-2], NiCl(OH), are frequently mentioned as intermediates for the production of nickel powder in aqueous solution. The binding energies for these compounds have been studied (55). 

Only 20—40% of the HNO is converted ia the reactor to nitroparaffins. The remaining HNO produces mainly nitrogen oxides (and mainly NO) and acts primarily as an oxidising agent. Conversions of HNO to nitroparaffins are up to about 20% when methane is nitrated. Conversions are, however, often ia the 36—40% range for nitrations of propane and / -butane. These differences ia HNO conversions are explained by the types of C—H bonds ia the paraffins. Only primary C—H bonds exist ia methane and ethane. In propane and / -butane, both primary and secondary C—H bonds exist. Secondary C—H bonds are considerably weaker than primary C—H bonds. The kinetics of reaction 6 (a desired reaction for production of nitroparaffins) are hence considerably higher for both propane and / -butane as compared to methane and ethane. Experimental results also iadicate for propane nitration that more 2-nitropropane [79-46-9] is produced than 1-nitropropane [108-03-2]. Obviously the hydroxyl radical attacks the secondary bonds preferentially even though there are more primary bonds than secondary bonds. 

Esters of nitro alcohols with primary alcohol groups can be prepared from the nitro alcohol and an organic acid, but nitro alcohols with secondary alcohol groups can be esterified only through the use of an acid chloride or anhydride. The nitrate esters of the nitro alcohols are obtained easily by treatment with nitric acid (qv). The resulting products have explosive properties but are not used commercially. 

Ttinitroparaffins can be prepared from 1,1-dinitroparaffins by electrolytic nitration, ie, electrolysis in aqueous caustic sodium nitrate solution (57). Secondary nitroparaffins dimerize on electrolytic oxidation (58) for example, 2-nitropropane yields 2,3-dimethyl-2,3-dinitrobutane, as well as some 2,2-dinitropropane. Addition of sodium nitrate to the anolyte favors formation of the former. The oxidation of salts of i7k-2-nitropropane with either cationic or anionic oxidants generally gives both 2,2-dinitropropane and acetone (59) with ammonium peroxysulfate, for example, these products are formed in 53 and 14% yields, respectively. Ozone oxidation of nitroso groups gives nitro compounds 2-nitroso-2-nitropropane [5275-46-7] (propylpseudonitrole), for example, yields 2,2-dinitropropane (60). 

Inhibition of Nitrosamine Formation. Nitrites can react with secondary amines and A/-substituted amides under the acidic conditions of the stomach to form /V-nitrosamines and A/-nitrosamides. These compounds are collectively called N-nitroso compounds. There is strong circumstantial evidence that in vivo A/-nitroso compounds production contributes to the etiology of cancer of the stomach (135,136), esophagus (136,137), and nasopharynx (136,138). Ascorbic acid consumption is negatively correlated with the incidence of these cancers, due to ascorbic acid inhibition of in vivo A/-nitroso compound formation (139). The concentration of A/-nitroso compounds formed in the stomach depends on the nitrate and nitrite intake. 

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